94 results on '"electric model"'
Search Results
2. Characterizing parameters and incorporating action potentials via the Hodgkin-Huxley model in a novel electric model for living cells.
- Author
-
Bougandoura, Omar, Achour, Yahia, Zaoui, Abdelhalim, and Starzyński, Jacek
- Subjects
- *
ACTION potentials , *ELECTROPORATION , *MEMBRANE potential , *LUMPED elements , *MUSCLE contraction , *MUSCLE cells - Abstract
To enhance our understanding of electroporation and optimize the pulses used within the frequency range of 1 kHz to 100 MHz, with the aim of minimizing side effects such as muscle contraction, we introduce a novel electrical model, structured as a 2D representation employing exclusively lumped elements. This model adeptly encapsulates the intricate dynamics of living cells' impedance variation. A distinguishing attribute of the proposed model lies in its capacity to decipher the distribution of transmembrane potential across various orientations within living cells. This aspect bears critical importance, particularly in contexts such as electroporation and cellular stimulation, where precise knowledge of potential gradients is pivotal. Furthermore, the augmentation of the proposed electrical model with the Hodgkin-Huxley (HH) model introduces an additional dimension. This integration augments the model's capabilities, specifically enabling the exploration of muscle cell stimulation and the generation of action potentials. This broader scope enhances the model's utility, facilitating comprehensive investigations into intricate cellular behaviors under the influence of external electric fields. In our research, we've introduced an enhanced electrical model for living cells. This model simplifies cell behavior using only basic electrical components like resistors and capacitors. It's designed to mimic the real electrical properties of cells, particularly the cell membrane, which can change in response to electricity at different frequencies, ranging from 1 kHz to 100 MHz. This frequency range is essential for studying processes like electroporation, a technique used in various medical applications. Our model is represented in a two-dimensional structure, making it a handy tool for identifying transmembrane potential distributions, a critical factor in electroporation procedures. This means we can better understand how cells react to electrical impulses, which is crucial for improving electroporation techniques. Additionally, we've extended our model to include muscle cells by incorporating the Hodgkin-Huxley model, a well-established model for understanding electrical behavior in muscle cells. This allows us to study how muscles contract when exposed to different electrical pulses, a common side effect of electroporation procedures. By examining various pulse characteristics, we can determine which ones are best for minimizing muscle contractions during electroporation. In summary, our research has led to the development of a versatile electrical model for living cells. It not only helps us understand how cells respond to electricity in the context of electroporation but also provides insights into muscle contractions and how to optimize electrical pulses for medical treatments. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
3. NUMERICAL MODELING OF ELECTRICAL PARAMETERS OF LiFePO4 BATTERIES.
- Author
-
Buryk, Mykola, Lobodzinsky, Vadim, Buryk, Ivan, and Lisovyi, Oleksandr
- Subjects
- *
LITHIUM-ion batteries , *STORAGE batteries , *ENERGY storage , *ELECTRICAL energy , *ELECTRIC circuits - Abstract
The object of research is the physical processes of electric energy storage in Li-ion batteries. The problem being solved in the work is related to the lack of reliable mathematical models of storage batteries, which leads to the appearance of undesirable effects or emergency situations when changing operating modes. In the course of the work, Li-ion battery models based on electrochemical theory and electrical circuits were considered. The six most common equivalent battery replacement schemes are presented. The advantages and disadvantages of the considered substitution schemes are given. The dual-polarization mathematical model was found to most accurately describe the performance of the battery at the end of the discharge and charge cycles compared to the first-order Thevenin model, the RC model, and the active resistance battery model. The physical processes in the storage battery during pulse discharge, which is the main part of electrical energy storage systems based on electrochemical technology, were studied. Mathematical modeling was carried out in the Matlab software package using the Simulink application program package. The dependence of the parameters of the equivalent lithium-ion battery replacement scheme according to the second-order Thevenin model on the ambient temperature and state of charge is considered. It was established that the value of EMF E depends more on the change in SOC than on temperature. In turn, the active resistance ROM shows a greater dependence on temperature than on the change in SOC. At high temperatures, the resistance value decreases. The parameters R1 and C1 characterizing the electrochemical polarization vary in the range from 10 to 75 % SOC. The parameters R2 and C2, which depend on the concentration polarization, vary in the intervals from 0 to 25 % SOC and 75 to 100 % SOC. The recommendations for choosing a Li-ion battery model developed in the work can be used in practice. The established dependencies will help to better design electrical energy storage systems based on electrochemical technology [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
4. Predictive Cell Culture Time Evolution Based on Electric Models.
- Author
-
Serrano, Juan Alfonso, Pérez, Pablo, Daza, Paula, Huertas, Gloria, and Yúfera, Alberto
- Subjects
CELL culture ,SOCIAL evolution ,FREQUENCIES of oscillating systems ,SALINE solutions ,CELL growth - Abstract
Obtaining cell concentration measurements from a culture assay by using bioimpedance is a very useful method that can be used to translate impedances to cell concentration values. The purpose of this study was to find a method to obtain the cell concentration values of a given cell culture assay in real time by using an oscillator as the measurement circuit. From a basic cell–electrode model, enhanced models of a cell culture immersed in a saline solution (culture medium) were derived. These models were used as part of a fitting routine to estimate the cell concentration in a cell culture in real time by using the oscillation frequency and amplitude delivered by the measurement circuits proposed by previous authors. Using real experimental data (the frequency and amplitude of oscillations) that were obtained by connecting the cell culture to an oscillator as the load, the fitting routine was simulated, and real-time data of the cell concentration were obtained. These results were compared to concentration data that were obtained by using traditional optical methods for counting. In addition, the error that we obtained was divided and analyzed in two parts: the first part of the experiment (when the few cells were adapting to the culture medium) and the second part of the experiment (when the cells exponentially grew until they completely covered the well). Low error values were obtained during the growth phase of the cell culture (the relevant phase); therefore, the results obtained were considered promising and show that the fitting routine is valid and that the cell concentration can be measured in real time by using an oscillator. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
5. From Bioimpedance to Volume Estimation: A Model for Edema Calculus in Human Legs.
- Author
-
Scaliusi, Santiago F., Gimenez, Luis, Pérez, Pablo, Martín, Daniel, Olmo, Alberto, Huertas, Gloria, Medrano, F. Javier, and Yúfera, Alberto
- Subjects
HEART failure patients ,EDEMA ,CALCULUS ,HEART failure ,CAUSES of death ,LEG - Abstract
Heart failure (HF) is a severe disease and one of the most important causes of death in our society nowadays. A significant percentage of patients hospitalized for decompensation of heart failure are readmitted after some weeks or months due to an expected bad and uncontrolled HF evolution due to the lack of the patient supervision in real time. Herein is presented a straightforward electric model useful for volume leg section calculus based on the bioimpedance test as a way to assist with the acute HF patient's supervision. The method has been developed for time-evolution edema evaluation in patients' corresponding legs. The data are picked up with a wearable device specifically developed for acute heart failure patients. As an initial step, a calibration method is proposed to extract the extracellular volume component from bioimpedance measurements done in healthy subjects, and then applied to unhealthy ones. The intra- and extracellular resistance components are calculated from fitted Cole–Cole model parameters derived from BI spectroscopy measurements. Results obtained in a pilot assay, with healthy subjects and heart failure subjects, show sensitivities in leg volume [mL/Ω], with much lower values for healthy than in unhealthy people, being an excellent biomarker to discriminate between both. Finally, circadian cycle evolution for leg volume has been measured from the bioimpedance test as an extension of the work, enabling an alternative parameter for the characterization of one day of human activity for any person. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
6. Double Gate JFET Improved Model for Analog Integrated Circuits
- Author
-
Y. D. Galkin, O. V. Dvornikov, and V. A. Tchekhovski
- Subjects
junction field-effect transistor ,double gate transistor ,electric model ,i-v characteristic simulation ,Electronics ,TK7800-8360 - Abstract
A double gate JFETs are often used in analog integrated circuits to provide an extremely low input current and capacitance when the top gate is controlled. Circuit synthesis and modeling of analog IC with such a field-effect transistor are possible only if there are models that adequately describe the features of its operation, namely, changing of the current-voltage characteristics by the top gate controlling when a constant reverse voltage is applied to the bottom gate. The article considers the modernization of the well-known electrical model of the double gate field-effect transistor for the LTSpice software, which includes taking into account the influence of the top gate voltage by connecting two series-connected functional voltage sources to the top gate, one of which ensures the coincidence of the measurement results and the simulation of the drain current at a low voltage between the top gate and the source, and the second – when the voltage between the top gate and the source is close to the cutoff voltage. A method for identifying the parameters of functional voltage sources is presented. The proposed model of a double gate field-effect transistor is advisable to use in the IC design of various analog devices, especially electrometric operational amplifiers and charge-sensitive amplifiers.
- Published
- 2022
- Full Text
- View/download PDF
7. Experimental and Numerical Investigations on the Parameters of a Synchronous Machine Prototype with High-Temperature Superconductor Armature Windings
- Author
-
Hocine Menana and Yazid Statra
- Subjects
HTS armature winding ,axial flux synchronous machine ,electric model ,AC losses ,modeling ,measurements ,Physics ,QC1-999 - Abstract
In their applications in electrical machines, high-temperature superconductors (HTSs) are mainly used as inductors in synchronous machines due to the AC losses which can lead to high cryogenic costs. In this work, we show the possibility of their use as armature windings, handling some precautions. The approach is based on the combined use of modeling and measurements. The construction and the preliminary tests of a handmade prototype of an axial field HTS synchronous machine are presented. Several tests have been conducted at liquid nitrogen temperature. The measurements have been confirmed by modeling results. The preliminary tests on the prototype, in both modeling and measurements, are very promising.
- Published
- 2023
- Full Text
- View/download PDF
8. Predictive Cell Culture Time Evolution Based on Electric Models
- Author
-
Juan Alfonso Serrano, Pablo Pérez, Paula Daza, Gloria Huertas, and Alberto Yúfera
- Subjects
bioimpedance ,cell culture ,computer-aided design (CAD) ,electric model ,fractional order (FO) ,microelectrode ,Biotechnology ,TP248.13-248.65 - Abstract
Obtaining cell concentration measurements from a culture assay by using bioimpedance is a very useful method that can be used to translate impedances to cell concentration values. The purpose of this study was to find a method to obtain the cell concentration values of a given cell culture assay in real time by using an oscillator as the measurement circuit. From a basic cell–electrode model, enhanced models of a cell culture immersed in a saline solution (culture medium) were derived. These models were used as part of a fitting routine to estimate the cell concentration in a cell culture in real time by using the oscillation frequency and amplitude delivered by the measurement circuits proposed by previous authors. Using real experimental data (the frequency and amplitude of oscillations) that were obtained by connecting the cell culture to an oscillator as the load, the fitting routine was simulated, and real-time data of the cell concentration were obtained. These results were compared to concentration data that were obtained by using traditional optical methods for counting. In addition, the error that we obtained was divided and analyzed in two parts: the first part of the experiment (when the few cells were adapting to the culture medium) and the second part of the experiment (when the cells exponentially grew until they completely covered the well). Low error values were obtained during the growth phase of the cell culture (the relevant phase); therefore, the results obtained were considered promising and show that the fitting routine is valid and that the cell concentration can be measured in real time by using an oscillator.
- Published
- 2023
- Full Text
- View/download PDF
9. Numerical modeling of electrical parameters of LiFePO4 batteries
- Abstract
The object of research is the physical processes of electric energy storage in Li-ion batteries. The problem being solved in the work is related to the lack of reliable mathematical models of storage batteries, which leads to the appearance of undesirable effects or emergency situations when changing operating modes. In the course of the work, Li-ion battery models based on electrochemical theory and electrical circuits were considered. The six most common equivalent battery replacement schemes are presented. The advantages and disadvantages of the considered substitution schemes are given. The dual-polarization mathematical model was found to most accurately describe the performance of the battery at the end of the discharge and charge cycles compared to the first-order Thevenin model, the RC model, and the active resistance battery model. The physical processes in the storage battery during pulse discharge, which is the main part of electrical energy storage systems based on electrochemical technology, were studied. Mathematical modeling was carried out in the Matlab software package using the Simulink application program package. The dependence of the parameters of the equivalent lithium-ion battery replacement scheme according to the second-order Thevenin model on the ambient temperature and state of charge is considered. It was established that the value of EMF E depends more on the change in SOC than on temperature. In turn, the active resistance ROM shows a greater dependence on temperature than on the change in SOC. At high temperatures, the resistance value decreases. The parameters R1 and C1 characterizing the electrochemical polarization vary in the range from 10 to 75 % SOC. The parameters R2 and C2, which depend on the concentration polarization, vary in the intervals from 0 to 25 % SOC and 75 to 100 % SOC. The recommendations for choosing a Li-ion battery model developed in the work can be used in practice. The established dependencies will help to bet
- Published
- 2024
10. Kalman filter applied to Thevenin’s modeling of a lead-acid battery.
- Author
-
Palacio-Fernández, Jose Alfredo and Quintero, Edwin García
- Subjects
KALMAN filtering ,LEAD-acid batteries ,OPEN-circuit voltage ,NOISE measurement - Abstract
This article determines the internal parameters of a battery analyzed from its circuit equivalent, reviewing important information that can help to identify the battery’s state of charge (SOC) and its state of health (SOH). Although models that allow the dynamics of different types of batteries to be identified have been developed, few have defined the lead-acid battery model from the analysis of a filtered signal by applying a Kalman filter, particularly taking into account the measurement of noise not just at signal output but also at its input (this is a novelty raised from the experimental). This study proposes a model for lead-acid batteries using tools such as MATLAB® and Simulink®. First, a method of filtering the input and output signal is presented, and then a method for identifying parameters from 29 charge states is used for a leadacid battery. Different SOCs are related to different values of open circuit voltage (OCV). Ultimately, improvements in model estimation are shown using a filter that considers system and sensor noise since the modeled and filtered signal is closer to the original signal than the unfiltered modeled signal. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
11. МОДЕЛЮВАННЯ ОПТОЕЛЕКТРОННОГО НАВАНТАЖЕННЯ, ЯКЕ ЖИВИТЬСЯ ВІД ФОТОЕЛЕМЕНТА ТА АКУМУЛЯТОРА
- Author
-
Бондаренко, Д. В.
- Abstract
Copyright of Renewable Energy / Vidnovluvana Energetyka is the property of Institute of Renewable Energy of NAS of Ukraine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2020
- Full Text
- View/download PDF
12. Predictive Cell Culture Time Evolution Based on Electric Models
- Author
-
Universidad de Sevilla. Departamento de Tecnología Electrónica, Universidad de Sevilla. Departamento de Biología Celular, Universidad de Sevilla. Departamento de Electrónica y Electromagnetismo, Ministerio de Ciencia e Innovación (MICIN). España, Serrano Viseas, Juan Alfonso, Pérez García, Pablo, Daza Navarro, María Paula, Huertas Sánchez, Gloria, Yúfera García, Alberto, Universidad de Sevilla. Departamento de Tecnología Electrónica, Universidad de Sevilla. Departamento de Biología Celular, Universidad de Sevilla. Departamento de Electrónica y Electromagnetismo, Ministerio de Ciencia e Innovación (MICIN). España, Serrano Viseas, Juan Alfonso, Pérez García, Pablo, Daza Navarro, María Paula, Huertas Sánchez, Gloria, and Yúfera García, Alberto
- Abstract
Obtaining cell concentration measurements from a culture assay by using bioimpedance is a very useful method that can be used to translate impedances to cell concentration values. The purpose of this study was to find a method to obtain the cell concentration values of a given cell culture assay in real time by using an oscillator as the measurement circuit. From a basic cell–electrode model, enhanced models of a cell culture immersed in a saline solution (culture medium) were derived. These models were used as part of a fitting routine to estimate the cell concentration in a cell culture in real time by using the oscillation frequency and amplitude delivered by the measurement circuits proposed by previous authors. Using real experimental data (the frequency and amplitude of oscillations) that were obtained by connecting the cell culture to an oscillator as the load, the fitting routine was simulated, and real-time data of the cell concentration were obtained. These results were compared to concentration data that were obtained by using traditional optical methods for counting. In addition, the error that we obtained was divided and analyzed in two parts: the first part of the experiment (when the few cells were adapting to the culture medium) and the second part of the experiment (when the cells exponentially grew until they completely covered the well). Low error values were obtained during the growth phase of the cell culture (the relevant phase); therefore, the results obtained were considered promising and show that the fitting routine is valid and that the cell concentration can be measured in real time by using an oscillator.
- Published
- 2023
13. From Bioimpedance to Volume Estimation: A Model for Edema Calculus in Human Legs
- Author
-
Universidad de Sevilla. Departamento de Electrónica y Electromagnetismo, Universidad de Sevilla. Departamento de Biología Celular, Universidad de Sevilla. Departamento de Tecnología Electrónica, Ministerio de Ciencia, Innovación y Universidades (MICINN). España, Plan Andaluz de Investigación, Desarrollo e Innovación (PAIDI). España, Fernandez Scagliusi, Santiago Joaquín, Giménez, Luis, Pérez García, Pablo, Martín Fernández, Daniel, Olmo Fernández, Alberto, Huertas Sánchez, Gloria, Medrano Ortega, Francisco Javier, Yúfera García, Alberto, Universidad de Sevilla. Departamento de Electrónica y Electromagnetismo, Universidad de Sevilla. Departamento de Biología Celular, Universidad de Sevilla. Departamento de Tecnología Electrónica, Ministerio de Ciencia, Innovación y Universidades (MICINN). España, Plan Andaluz de Investigación, Desarrollo e Innovación (PAIDI). España, Fernandez Scagliusi, Santiago Joaquín, Giménez, Luis, Pérez García, Pablo, Martín Fernández, Daniel, Olmo Fernández, Alberto, Huertas Sánchez, Gloria, Medrano Ortega, Francisco Javier, and Yúfera García, Alberto
- Abstract
Heart failure (HF) is a severe disease and one of the most important causes of death in our society nowadays. A significant percentage of patients hospitalized for decompensation of heart failure are readmitted after some weeks or months due to an expected bad and uncontrolled HF evolution due to the lack of the patient supervision in real time. Herein is presented a straightforward electric model useful for volume leg section calculus based on the bioimpedance test as a way to assist with the acute HF patient’s supervision. The method has been developed for time-evolution edema evaluation in patients’ corresponding legs. The data are picked up with a wearable device specifically developed for acute heart failure patients. As an initial step, a calibration method is proposed to extract the extracellular volume component from bioimpedance measurements done in healthy subjects, and then applied to unhealthy ones. The intra- and extracellular resistance components are calculated from fitted Cole–Cole model parameters derived from BI spectroscopy measurements. Results obtained in a pilot assay, with healthy subjects and heart failure subjects, show sensitivities in leg volume [mL/Ω], with much lower values for healthy than in unhealthy people, being an excellent biomarker to discriminate between both. Finally, circadian cycle evolution for leg volume has been measured from the bioimpedance test as an extension of the work, enabling an alternative parameter for the characterization of one day of human activity for any person.
- Published
- 2023
14. Predictive Cell Culture Time Evolution Based on Electric Models
- Author
-
Agencia Estatal de Investigación (España), Ministerio de Ciencia e Innovación (España), Serrano, Juan Alfonso, Pérez, Pablo, Daza, Paula, Huertas, Gloria, Yúfera, Alberto, Agencia Estatal de Investigación (España), Ministerio de Ciencia e Innovación (España), Serrano, Juan Alfonso, Pérez, Pablo, Daza, Paula, Huertas, Gloria, and Yúfera, Alberto
- Abstract
Obtaining cell concentration measurements from a culture assay by using bioimpedance is a very useful method that can be used to translate impedances to cell concentration values. The purpose of this study was to find a method to obtain the cell concentration values of a given cell culture assay in real time by using an oscillator as the measurement circuit. From a basic cell–electrode model, enhanced models of a cell culture immersed in a saline solution (culture medium) were derived. These models were used as part of a fitting routine to estimate the cell concentration in a cell culture in real time by using the oscillation frequency and amplitude delivered by the measurement circuits proposed by previous authors. Using real experimental data (the frequency and amplitude of oscillations) that were obtained by connecting the cell culture to an oscillator as the load, the fitting routine was simulated, and real-time data of the cell concentration were obtained. These results were compared to concentration data that were obtained by using traditional optical methods for counting. In addition, the error that we obtained was divided and analyzed in two parts: the first part of the experiment (when the few cells were adapting to the culture medium) and the second part of the experiment (when the cells exponentially grew until they completely covered the well). Low error values were obtained during the growth phase of the cell culture (the relevant phase); therefore, the results obtained were considered promising and show that the fitting routine is valid and that the cell concentration can be measured in real time by using an oscillator.
- Published
- 2023
15. Electromagnetic-thermal coupled modelling and analysis of inter-turn short-circuit faults of a permanent magnet alternator
- Author
-
Liang Chen, Jiabin Wang, and Zhigang Sun
- Subjects
finite element analysis ,PWM rectifiers ,fault diagnosis ,worst case inter-turn short-circuit condition ,inter-turn short-circuit faults ,permanent magnet alternator ,computationally efficient model ,steady-state behaviours ,load ,aerospace applications ,fault conditions ,finite element ,circuit coupled co-simulation ,fault signatures ,fault detection techniques ,electric model ,thermal model ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
This paper describes a computationally efficient model for predicting transient and steady-state behaviours of a permanent magnet alternator (PMA) connected to an asymmetric PWM rectifier and load in aerospace applications under healthy and fault conditions. The model is validated by finite element and circuit coupled co-simulation. The developed model is used to predict the PMA performance under fault conditions and to identify fault signatures that can be exploited for the development of fault detection techniques. The developed electric model is coupled to the thermal model to predict hotspot temperature of the winding under the worst case inter-turn short-circuit condition and to estimate the winding lifetime.
- Published
- 2019
- Full Text
- View/download PDF
16. Predictive Cell Culture Time Evolution Based on Electric Models
- Author
-
Alfonso Serrano, Juan, Pérez García, Pablo, Daza Navarro, María Paula, Huertas Sánchez, Gloria, Yúfera García, Alberto, Universidad de Sevilla. Departamento de Tecnología Electrónica, Universidad de Sevilla. Departamento de Biología Celular, Universidad de Sevilla. Departamento de Electrónica y Electromagnetismo, Universidad de Sevilla. TIC178: Diseño y Test de Circuitos Integrados de Señal Mixta, Universidad de Sevilla. BIO132: Citoquímica Ultraestructural, and MCIN/ AEI /10.13039/501100011033/ y por FEDER (Una manera de hacer Europa) PID2021-122529OB-I00
- Subjects
Bioimpedance ,Electric model ,Oscillation-based test (OBT) ,Microelectrode ,Cell culture ,Fractional order (FO) ,Computer-aided design (CAD) - Abstract
Obtaining cell concentration measurements from a culture assay by using bioimpedance is a very useful method that can be used to translate impedances to cell concentration values. The purpose of this study was to find a method to obtain the cell concentration values of a given cell culture assay in real time by using an oscillator as the measurement circuit. From a basic cell–electrode model, enhanced models of a cell culture immersed in a saline solution (culture medium) were derived. These models were used as part of a fitting routine to estimate the cell concentration in a cell culture in real time by using the oscillation frequency and amplitude delivered by the measurement circuits proposed by previous authors. Using real experimental data (the frequency and amplitude of oscillations) that were obtained by connecting the cell culture to an oscillator as the load, the fitting routine was simulated, and real-time data of the cell concentration were obtained. These results were compared to concentration data that were obtained by using traditional optical methods for counting. In addition, the error that we obtained was divided and analyzed in two parts: the first part of the experiment (when the few cells were adapting to the culture medium) and the second part of the experiment (when the cells exponentially grew until they completely covered the well). Low error values were obtained during the growth phase of the cell culture (the relevant phase); therefore, the results obtained were considered promising and show that the fitting routine is valid and that the cell concentration can be measured in real time by using an oscillator.
- Published
- 2023
17. Energy Harvesting through Dance Floor using Piezoelectric Device
- Author
-
Gupta, Abhishek, Imran, Mohd., Agarwal, Resham, Yadav, Rakesh, Jangir, Priyanka, and Poonia, Rakshit
- Published
- 2016
18. Proyectos hidroeléctricos y resistencias comunitarias en defensa de los ríos en Costa Rica: un análisis geográfico.
- Author
-
Gutiérrez Arguedas, Alberto and Villalobos Villalobos, Dany
- Subjects
- *
HYDROELECTRIC power plants , *SOCIAL structure , *COMMUNITY organization , *ELECTRIC power , *SOCIAL movements , *STREAM restoration , *FUZZY sets - Abstract
Most of the electric power in Costa Rica comes from hydroelectric power plants, which have caused strong socioenvironmental impacts and provoked conflicts in many of the country's communities. The article analyzes the tension between the expansion of hydroelectric projects and community resistance in defense of the rivers of Costa Rica, from a geographic perspective. To that effect, it discusses and interprets those conflicts by mapping the operating hydroelectric plants and the focal points of community resistance to them, at the national level. Different types of sources were consulted and combined, and the projects and resistance movements were systematized. One of the results was the identification of numerous processes of community resistance in defense of the rivers, widely distributed throughout the country's different regions. Proof of that is the fact that many projects about to be built have been stopped due to those resistance movements, especially in the last two decades. Those struggles gave rise to a nationwide social movement in defense of the rivers, thus positioning the communities and their organizations as social actors in a field that had historically excluded them from decision making. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
19. Power Estimation of a Current Supplied DBD Considering the Transformer Parasitic Elements.
- Author
-
Rueda, Vanesa, Wiesner, Arnold, Diez, Rafael, and Piquet, Hubert
- Subjects
- *
ELECTRIC power , *POWER resources , *ELECTRIC inductance , *ELECTRIC capacity , *PLASMA sources , *CONVERTERS (Electronics) - Abstract
Power estimation of a DBD device supplied by a current source converter is studied in this article, pointing out the prominent contribution of the transformer parasitic elements. The impact of the stray capacitance and magnetizing inductance is stated and an iterative method that estimates the electrical power and DBD waveforms is presented. Results show that the magnetizing inductance can enhance the electrical power without changing the current ratings of the converter and that the stray capacitance must be minimized. Moreover, the experimental results reveal the need for a better DBD model to properly estimate the power. In consequence, an improved model is proposed and validated using a DBD excimer lamp in a wide range of electrical operating conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
20. Electromagnetic-thermal coupled modelling and analysis of inter-turn short-circuit faults of a permanent magnet alternator.
- Author
-
Chen, Liang, Wang, Jiabin, and Sun, Zhigang
- Subjects
PERMANENT magnet motors ,ALTERNATING current generators ,ELECTRIC power system faults ,ELECTRIC current rectifiers ,FINITE element method - Abstract
This paper describes a computationally efficient model for predicting transient and steady-state behaviours of a permanent magnet alternator (PMA) connected to an asymmetric PWM rectifier and load in aerospace applications under healthy and fault conditions. The model is validated by finite element and circuit coupled co-simulation. The developed model is used to predict the PMA performance under fault conditions and to identify fault signatures that can be exploited for the development of fault detection techniques. The developed electric model is coupled to the thermal model to predict hotspot temperature of the winding under the worst case inter-turn short-circuit condition and to estimate the winding lifetime. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
21. ЕКВІВАЛЕНТНІ СХЕМИ АКУМУЛЯТОРІВ ЕЛЕКТРОЕНЕРГІЇ, ЯКІ ПІДКЛЮЧЕНІ ДО СОНЯЧНИХ ФОТОЕЛЕМЕНТІВ
- Author
-
Бондаренко, Д. В.
- Abstract
Copyright of Renewable Energy / Vidnovluvana Energetyka is the property of Institute of Renewable Energy of NAS of Ukraine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2019
- Full Text
- View/download PDF
22. From Bioimpedance to Volume Estimation: A Model for Edema Calculus in Human Legs
- Author
-
Santiago F. Scaliusi, Luis Gimenez, Pablo Pérez, Daniel Martín, Alberto Olmo, Gloria Huertas, F. Javier Medrano, Alberto Yúfera, Universidad de Sevilla. Departamento de Electrónica y Electromagnetismo, Universidad de Sevilla. Departamento de Biología Celular, Universidad de Sevilla. Departamento de Tecnología Electrónica, Ministerio de Ciencia, Innovación y Universidades (MICINN). España, and Plan Andaluz de Investigación, Desarrollo e Innovación (PAIDI). España
- Subjects
Heart failure (HF) ,Bioimpedance ,Computer Networks and Communications ,Hardware and Architecture ,Control and Systems Engineering ,Electric model ,Signal Processing ,Circadian cycle ,Electrical and Electronic Engineering ,bioimpedance ,circadian cycle ,electric model ,heart failure (HF) ,wearable devices ,Wearable devices - Abstract
Heart failure (HF) is a severe disease and one of the most important causes of death in our society nowadays. A significant percentage of patients hospitalized for decompensation of heart failure are readmitted after some weeks or months due to an expected bad and uncontrolled HF evolution due to the lack of the patient supervision in real time. Herein is presented a straightforward electric model useful for volume leg section calculus based on the bioimpedance test as a way to assist with the acute HF patient’s supervision. The method has been developed for time-evolution edema evaluation in patients’ corresponding legs. The data are picked up with a wearable device specifically developed for acute heart failure patients. As an initial step, a calibration method is proposed to extract the extracellular volume component from bioimpedance measurements done in healthy subjects, and then applied to unhealthy ones. The intra- and extracellular resistance components are calculated from fitted Cole–Cole model parameters derived from BI spectroscopy measurements. Results obtained in a pilot assay, with healthy subjects and heart failure subjects, show sensitivities in leg volume [mL/Ω], with much lower values for healthy than in unhealthy people, being an excellent biomarker to discriminate between both. Finally, circadian cycle evolution for leg volume has been measured from the bioimpedance test as an extension of the work, enabling an alternative parameter for the characterization of one day of human activity for any person. Ministerio de Ciencia, Innovación y Universidades DTS19/00134, DTS19/00137 Plan Andaluz de Investigación, Desarrollo e Innovación AT21-00010-USE
- Published
- 2023
23. ЭЛЕКТРИЧЕСКАЯ МОДЕЛЬ С ИДЕАЛЬНЫМИ ЭЛЕМЕНТАМИ ДЛЯ ПОИСКА КРАТЧАЙШЕГО ПУТИ НА ВЗВЕШЕННОМ ОРИЕНТИРОВАННОМ ГРАФЕ
- Author
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Гнатенко, В. Ю., Ступень, П. В., Дікусар, К. В., and Шутєєв, Е. І.
- Abstract
The problem of determining the shortest path in a weighted and directed graph is considered using an electric model with ideal diodes, voltage and current sources. Theoretical studies in the field of mathematical modeling of electrical circuits with ideal elements have been carried out. An example of determining the shortest path in a given weighted directed graph is considered. In problems of small dimension, analog electric models can be used. However, for large graphs, analog models become very cumbersome because of the need to include an isolated source of electrical energy in each circuit, and the accuracy of the solution is low because of the non-ideality of the characteristics of the elements. In this paper, we consider the development of a representation model of a weighted and directed graph without the use of a structural matrix or any other topological matrices. Instead, it is proposed to form and process in the process of analysis a list of branches with their inherent characteristics and parameters. The aim of the paper is to justify the electric model for finding the shortest path in a weighted oriented graph, the representation of the algorithm for implementing and illustrating the effectiveness of the method. Since the initial electric circuit does not contain energy storage devices and, in principle, a transient process is not possible in it, it is proposed to convert the initial electric circuit to a dynamic one by attaching to each node of the circuit in capacity, the other end of which is connected to a basic node that does not belong to this scheme and is common to all containers. As a result, a transient process becomes possible, at the end of which the capacitance currents will become equal to zero and will not affect the distribution of currents and voltages in the circuit. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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24. Electric Current Transmission Through Tissues of the Vestibular Labyrinth of a Patient: Perfection of the Vestibular Implant.
- Author
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Demkin, V. P., Shchetinin, P. P., Melnichuk, S. V., Kingma, H., Van de Berg, R., Pleshkov, M. O., and Starkov, D. N.
- Subjects
- *
ELECTRIC currents , *VESTIBULAR apparatus , *ELECTRODES , *DIELECTRIC properties , *ELECTRIC impedance , *SURGERY - Abstract
An electric model of current transmission through tissues of the vestibular labyrinth of a patient is suggested. To stimulate directly the vestibular nerve in surgical operation, terminations of the electrodes are implanted through the bone tissue of the labyrinth into the perilymph in the vicinity of the vestibular nerve. The biological tissue of the vestibular labyrinth surrounding the electrodes and having heterogeneous composition possesses conductive and dielectric properties. Thus, when a current pulse from the vestibular implant is applied to one of the electrodes, conductive disturbance currents may arise between the electrodes and the vestibular nerves that can significantly deteriorate the direct signal quality. To study such signals and to compensate for the conductive disturbance currents, an equivalent electric circuit with actual electric impedance properties of tissues of the vestibular system is suggested, and the time parameters of the conductive disturbance current transmission are calculated. It is demonstrated that these parameters can reach large values. The suggested electric model and the results of calculations can be used for perfection of the vestibular implant. [ABSTRACT FROM AUTHOR]
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- 2018
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25. Kalman filter applied to Thevenin's modeling of a lead-acid battery
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Jose Alfredo Palacio-Fernández and Edwin García Quintero
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Identification ,Open circuit voltage ,Electric model ,State of charge - Abstract
This article determines the internal parameters of a battery analyzed from its circuit equivalent, reviewing important information that can help to identify the battery’s state of charge (SOC) and its state of health (SOH). Although models that allow the dynamics of different types of batteries to be identified have been developed, few have defined the lead-acid battery model from the analysis of a filtered signal by applying a Kalman filter, particularly taking into account the measurement of noise not just at signal output but also at its input (this is a novelty raised from the experimental). This study proposes a model for lead-acid batteries using tools such as MATLAB® and Simulink®. First, a method of filtering the input and output signal is presented, and then a method for identifying parameters from 29 charge states is used for a leadacid battery. Different SOCs are related to different values of open circuit voltage (OCV). Ultimately, improvements in model estimation are shown using a filter that considers system and sensor noise since the modeled and filtered signal is closer to the original signal than the unfiltered modeled signal.
- Published
- 2022
26. Modelización de materiales piezoeléctricos como generadores de energía
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Vázquez Rodríguez, M., Jiménez Martínez, F. J., and de Frutos, J.
- Subjects
Piezoelectric material ,electric model ,power generation ,Material piezoeléctrico ,modelo eléctrico ,generación de energía ,Clay industries. Ceramics. Glass ,TP785-869 - Abstract
This paper presents the method to determine electrical equivalent models of piezoelectric materials used as electric power generating elements. The models developed from the experimental results have been used to obtain the type, amount and optimal topological structure of semiconductor elements needed in the input stage of the power generation system, and its behaviour under variable power supply demand.En este trabajo se presenta el estudio realizado para determinar los modelos eléctricos equivalentes de materiales de tipo piezoeléctrico, para evaluar su capacidad como elementos generadores de energía eléctrica. Los diferentes modelos desarrollados a partir de los resultados experimentales registrados, se han utilizado para obtener la estructura óptima de elementos semiconductores a utilizar en la etapa de entrada del sistema de generación y acumulación de energía eléctrica, teniendo en cuenta su morfología, tipo de semiconductor a utilizar y número necesario, así como su comportamiento ante una demanda variable de potencia a suministrar
- Published
- 2012
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27. ЭКСПЕРИМЕНТАЛЬНЫЕ ИССЛЕДОВАНИЯ ИМПЕДАНСА КОНДУКТОМЕТРИЧЕСКОГО ИНТЕРФЕЙСА Pt/H20 И Pt/KCl НА ЧАСТОТАХ 10 кГц - 1 МГц
- Author
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Михаль, А. А., Мелещук, Д. В., and Гребеньков, И. Н.
- Abstract
Copyright of Technical Electrodynamics / Tekhnichna Elektrodynamika is the property of National Academy of Sciences of Ukraine, Institute of Electrodynamics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2016
28. Electrophysical Properties and Determination of the Impedance of Vestibular Labyrinth Tissues
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Demkin, V. P., Melnichuk, S. V., Shchetinin, P. P., Kingma, H., and Van de Berg, R.
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- 2019
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29. Building an electric model vehicle and implementing an obstacle avoidance algorithm.
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Fenesan, Andrei, Pana, Teodor, Szocs, Daniel, and Chen, Wen-Hua
- Abstract
The present paper it presents an electric model vehicle with its own system of acquisition and computation of the information, on which we will test the collision control algorithms in indoors and outdoors with GPS localization. The algorithm used in this project is the Potential Field method. We chose to use a LIDAR sensor that can acquire distance data from the environment in 2D. The main objective of these tests is to make obstacle avoidance with mobile robot in Real-Time. [ABSTRACT FROM PUBLISHER]
- Published
- 2012
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30. Building an electric model vehicle with obstacle avoidance system.
- Author
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Fenesan, Andrei, Mcaree, Owen, Chen, Wen-Hua, Pana, Teodor, and Bamber, Tom
- Abstract
In this paper we propose an electric model vehicle with its own system of acquisition and computation of the information, on which we will test the collision control algorithms in indoors and outdoors with GPS localization. The algorithm used in this project is the Potential Field method. We chose to use a LIDAR sensor that can acquire distance data from the environment in 2D. The main objective of these tests is to make obstacle avoidance with mobile robot in Real-Time. [ABSTRACT FROM PUBLISHER]
- Published
- 2012
31. Análisis sistémico de la evolución de los componentes del modelo eléctrico de los estudiantes: Control, estructuras y procesos: Systemic analysis of the evolution of the components of the electrical model of the students: Control, structures and processes
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Merino, Cristian, Moreira, Patricia, and Marzabal, Ainoa
- Subjects
modelling ,modelización ,estructura ,modelo eléctrico ,model elèctric ,modelització ,procés ,process ,structure ,electric model ,control ,proceso - Abstract
Els currículums de Ciències assenyalen la rellevància de comprendre els fenòmens elèctrics, a causa de les múltiples aplicacions tecnològiques actuals basades en l'electricitat. No obstant això, els estudiants tenen dificultats per comprendre la naturalesa electromagnètica de la matèria, i es requereixen evidències empíriques de les formes en què les idees dels estudiants es van transformant a mesura que adquireixen experiència i coneixement conceptual sobre electricitat. Aquest estudi es focalitza en l'anàlisi de les explicacions d'estudiants de secundària sobre fenòmens elèctrics, amb el propòsit de caracteritzar l'evolució dels seus models expressats durant una seqüència didàctica basada en fenòmens d'electrització. La proposta d'anàlisi qualitativa, des d'una perspectiva sistèmica, identifica els components d'estructura, procés i control referits pels 30 estudiants de la mostra, en les explicacions de cinc fenòmens observats, caracteritzant l'evolució del model elèctric dels estudiants. Els nostres resultats mostren que les trajectòries d'aprenentatge dels estudiants són poc convergents i presenten discontinuïtats. La descomposició del model elèctric ens ha permès evidenciar que els estudiants construeixen models limitats pels processos observats, i tenen dificultats per transitar al nivell microscòpic, el que pot contribuir a orientar la selecció de fenòmens per part dels professors per aconseguir processos de modelització més efectius. Science curricula indicate the relevance of understanding electrical phenomena, due to the multiple current technological applications based on electricity. However, students have difficulty understanding the electromagnetic nature of matter, and empirical evidence is required of the ways in which students' ideas are transformed as they gain experience and conceptual knowledge about electricity. This study focuses on the analysis of secondary school students' explanations of electrical phenomena, with the purpose of characterizing the evolution of their models expressed during a didactic sequence based on electrification phenomena. The proposal of qualitative analysis, from a systemic perspective, identifies the structure, process and control components referred by the 30 students of the sample, in the explanations of five observed phenomena, characterizing the evolution of students' electrical model. Our results show that the learning trajectories of students are not convergent and present discontinuities. The decomposition of the electrical model has allowed us to show that students build models limited by the observed processes, and have difficulties to move to the microscopic level, which can help to guide the selection of phenomena by teachers to achieve more effective modeling processes. Los currículos de Ciencias señalan la relevancia de comprender los fenómenos eléctricos, debido a las múltiples aplicaciones tecnológicas actuales basadas en la electricidad. Sin embargo, los estudiantes tienen dificultades para comprender la naturaleza electromagnética de la materia, y se requieren evidencias empíricas de las formas en que sus ideas se van transformando a medida que adquieren experiencia y conocimiento conceptual sobre electricidad. Este estudio se focaliza en el análisis de las explicaciones de estudiantes de secundaria sobre fenómenos eléctricos, con el propósito de caracterizar la evolución de sus modelos expresados durante una secuencia didáctica basada en fenómenos de electrización. La propuesta de análisis cualitativo, desde una perspectiva sistémica, identifica los componentes de estructura, proceso y control referidos por 30 estudiantes, en las explicaciones de cinco fenómenos observados, caracterizando la evolución del modelo eléctrico de los estudiantes. Nuestros resultados muestran que las trayectorias de aprendizaje son poco convergentes y presentan discontinuidades. La descomposición del modelo eléctrico nos ha permitido evidenciar que los estudiantes construyen modelos limitados por los procesos observados, y tienen dificultades para transitar al nivel microscópico, lo que puede contribuir a orientar la selección de fenómenos por parte de los profesores para lograr procesos de modelización más efectivos.
- Published
- 2021
32. A Generalized Electric Model for Mono and Polycrystalline Silicon in the Presence of Cracks and Random Defects.
- Author
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Berardone, Irene, Corrado, Mauro, and Paggi, Marco
- Abstract
Damage, micro-cracks, grain boundaries and other defects in solar cells are impacting on the electric power-loss of photovoltaic modules, their actual solar conversion efficiency and also their lifetime. In the present contribution, a one-dimensional model for simulating the electric current distribution in solar cells accounting for a distributed series resistance is generalized to the presence of partially conductive cracks. The proposed model is used to perform a quantitative analysis of electroluminescence (EL) images of cracked monocrystalline silicon solar cells. A further generalization in a stochastic direction is also proposed in order to take into account randomly distributed defects typical of polycrystalline silicon. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
33. Electro-thermal modelling of a supercapacitor and experimental validation.
- Author
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Berrueta, Alberto, San Martín, Idoia, Hernández, Andoni, Ursúa, Alfredo, and Sanchis, Pablo
- Subjects
- *
SUPERCAPACITORS , *CHEMISTRY experiments , *THERMAL analysis , *ELECTRIC capacity , *ELECTRIC potential , *ELECTRIC circuits - Abstract
Abstract: This paper reports on the electro-thermal modelling of a Maxwell supercapacitor (SC), model BMOD0083 with a rated capacitance of 83 F and rated voltage of 48 V. One electrical equivalent circuit was used to model the electrical behaviour whilst another served to simulate the thermal behaviour. The models were designed to predict the SC operating voltage and temperature, by taking the electric current and ambient temperature as input variables. A five-stage iterative method, applied to three experiments, served to obtain the parameter values for each model. The models were implemented in MATLAB-Simulink®, where they interacted to reciprocally provide information. These models were then validated through a number of tests, subjecting the SC to different current and frequency profiles. These tests included the validation of a bank of supercapacitors integrated into an electric microgrid, in a real operating environment. Satisfactory results were obtained from the electric and thermal models, with RMSE values of less than 0.65 V in all validations. [Copyright &y& Elsevier]
- Published
- 2014
- Full Text
- View/download PDF
34. Inclusive dynamic thermal and electric simulation model of solar PV systems under varying atmospheric conditions.
- Author
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Torres-Lobera, Diego and Valkealahti, Seppo
- Subjects
- *
ELECTRIC power , *HEAT storage , *COMPUTER simulation , *SOLAR energy , *PHOTOVOLTAIC power systems , *TEMPERATURE effect , *PREDICTION models - Abstract
Highlights: [•] We develop a state of the art inclusive thermal and electric model for PV systems. [•] We validate the simulations with real 1-s measurements data during 20days in 2013. [•] The average root mean square error in the predicted temperatures is 1.34°C. [•] The average normalized root mean square error in the predicted P–V curves is 1.98%. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
35. Contrôle d’une structure de traction/recharge pour véhicule électrique hybride
- Author
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Aghaei Hashjin, Saeid, Groupe de Recherche en Energie Electrique de Nancy (GREEN), Université de Lorraine (UL), ESME Sudria [Paris], Université de Lorraine, Babak Nahidmobarakeh, and El Hadj Miliani
- Subjects
Modèle électrique ,Electric model ,[SPI.NRJ]Engineering Sciences [physics]/Electric power ,Moteur électrique ,Electric machine ,Commande sans capteur ,Sensorless control ,Model-free control ,Electric vehicle ,Véhicule électrique ,[SPI.AUTO]Engineering Sciences [physics]/Automatic - Abstract
The electrification of the transportation is one of the relevant solutions to reduce greenhouse gas emissions. Indeed, new European standards impose increasingly restrictive limits on CO2 emissions per km. This is an important industrial issue for automobile manufacturers. Therefore, the industries are moving towards hybrid and electric vehicles in which an electric traction chain is present. This consists of an electrical machine, powered by a static power electronic converter connected to an electrical energy source and storage elements. For more than two decades, different topologies have been studied for electric traction and several solutions have been marketed. These products are increasingly light, reliable and efficient while respecting the constraints of the automobile manufacturers on the costs. This thesis focuses on improving the reliability of electromechanical energy conversion chains. The objective of the thesis is to continue the development of new actuator control laws ensuring better reliability of the traction chain. With this in mind, reducing the number of sensors in control of the conversion chain will be considered. In fact, there are already current sensors in traction chains. However, these generate significant additional costs because of their frequent failures and the need for replacement. Thus, current sensorless control of the AC drive systems allows the elimination of the sensors of the stator of the machine and therefore to avoid their cost. In this thesis, the model-free adaptive controller (MFAC) is presented to be used in the control of the conversion chain to reduce the number of sensors. In this regard, MFAC is used in two different approaches. First, it is used for controlling a WRSM system, with and without additional current sensors. Then, it is used for the control of the power converters used in the conversion chain. The experimental results, obtained on a test bench built in the laboratory, are conclusive in transient and steady-state: the unmeasured currents are converged with a satisfying precision for an automotive application and allow performing a current sensorless control of the machine. In addition, a satisfactory performance of MFAC is also obtained for controlling the power converters with only using one voltage sensor.; L’électrification des moyens de transport est considérée comme l’une des solutions pertinentes pour réduire les émissions des gaz à effet de serre. En effet, les nouvelles normes européennes imposent des limites de plus en plus restrictives sur les émissions de CO2 par km. Ceci est un enjeu industriel important pour les constructeurs d’automobiles. Par conséquent, ces derniers s’orientent vers les véhicules hybrides et électriques dans lesquels une chaine de traction électrique est présente. Celle-ci est constituée d’une machine électrique, alimentée par un convertisseur statique d’électronique de puissance connecté à une source d’énergie électrique et des éléments de stockage. Depuis plus de deux décennies, différentes topologies ont été étudiées pour la traction électrique et plusieurs solutions ont été commercialisées. Ces produits sont de plus en plus légers, fiables et efficaces tout en respectant les contraintes des constructeurs d’automobile sur les coûts. Cette thèse s’inscrit sur l’amélioration de la fiabilité des chaînes de conversion d’énergie électromécanique. Le travail de thèse a pour objectif de poursuivre le développement de nouvelles lois de commande d’actionneur assurant une meilleure fiabilité de la chaîne de traction. Dans cette optique, réduire le nombre de capteurs de la chaîne de conversion dans la commande sera envisagée. En effet, il existe déjà des capteurs de courant dans les chaînes de traction. Cependant, ceux-ci engendrent des surcoûts importants à cause de leurs défaillances fréquentes et la nécessité de remplacement très couteuse. Ainsi l’étude réalisée de commande de machine synchrone à griffes sans capteur de courant permet la suppression des capteurs du stator de la machine et donc de s’affranchir de leur coût. Dans cette thèse, le model-free adaptive Controller (MFAC) est présenté pour être utilisé dans le contrôle de la chaîne de conversion pour réduire le nombre de capteurs. À cet égard, MFAC est utilisé dans deux approches différentes. Premièrement, il a été utilisé pour le contrôle d'un système WRSM, avec et sans capteurs de courant supplémentaires. Puis, il a été utilisé pour le contrôle des convertisseurs de puissance utilisés dans la chaîne de conversion. Les résultats expérimentaux, obtenus sur un banc de test réalisé en laboratoire, sont concluants en régime établi : les courants non mesurés sont contrôlés avec une précision satisfaisante pour une application automobile et permettent le contrôle sans capteur de courant de la machine. En plus, une performance satisfaisante du MFAC est également obtenue pour commander les convertisseurs de puissance avec un seul capteur de tension.
- Published
- 2020
36. INVARIANT TRANSDUCERS OF CAPACITIVE SENSOR PARAMETERS INTO VOLTAGE.
- Author
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Herasym, M. R. and Pokhodylo, Y. V.
- Subjects
TRANSDUCERS ,ELECTRIC potential ,CAPACITIVE sensors ,DETECTORS ,MATHEMATICAL models - Abstract
This paper presents the importance of capacitive primary transdusers, by which the electrical parameters of products of nonelectric nature are monitored. The main objective is to provide a result invariance to the near-electrode impedance, as uninformative parameter and to provide a proper measurement mode. Different variants of construction of invariant transducers with four-electrode contact sensors, that realize the method of direct transformation "impedancevoltage" are considered. The electrical and mathematical models of sensors of a given current mode and given preset voltage are shown. By these transducers we can provide result invariance to the capacity of a double layer and to parameters of a test signal. Results can be used for designing the devices of monitoring the parameters of products quality by reactive and active components of admittance within the audiofrequency range simultaneously providing an appropriate measurement mode [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
37. A Passive Wireless Humidity Threshold Monitoring Sensor Principle Based on Deliquescent Salts and a Diffusion Based Irreversible State Change.
- Author
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Sauer, Sebastian and Fischer, Wolf-Joachim
- Abstract
Passive RFID transponder applications that require integrated sensors can greatly benefit from unconventional sensing strategies especially in situations where there is a need to continuously monitor environmental properties without having access to an integrated source of electric energy or an omnipresent reader station within communication range. Since, in many cases, information about the violation of a threshold value is of interest, alternative sensing strategies exploiting irreversible phenomena not considered or even avoided before, have the potential to find successful use in low-cost (e.g., chip-based sensor RFIDs) or lowest cost (e.g., chipless sensor RFIDs-either with or without transistors) wireless sensor applications. In this paper, a stand-alone, simple, passive, wireless humidity threshold sensor concept, and its realization are presented. This exploits the deliquescence phenomenon of salts. Based on a double planar coil arrangement, for which an electric model is given and a transfer function has been deduced, an oscillating circuit is formed. Its resonance frequency changes irreversibly, if a threshold relative humidity is exceeded for a certain exposition time. The sensor principle is demonstrated by the example of sodium chloride. Various measurements demonstrate the feasibility of the presented sensor approach. Sensor solutions based on a threshold activated irreversible state change might be a promising approach in order to monitor environmental parameters without a permanent supply of electric energy. [ABSTRACT FROM PUBLISHER]
- Published
- 2014
- Full Text
- View/download PDF
38. Hydroelectric Projects and Community Resistance in Defense of the Rivers of Costa Rica: A Geographic Analysis
- Author
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Gutiérrez Arguedas, Alberto, Villalobos Villalobos, Dany, Gutiérrez Arguedas, Alberto, and Villalobos Villalobos, Dany
- Abstract
Most of the electric power in Costa Rica comes from hydroelectric power plants, which have caused strong socio-environmental impacts and provoked conflicts in many of the country’s communities. The article analyzes the tension between the expansion of hydroelectric projects and community resistance in defense of the rivers of Costa Rica, from a geographic perspective. To that effect, it discusses and interprets those conflicts by mapping the operating hydroelectric plants and the focal points of community resistance to them, at the national level. Different types of sources were consulted and combined, and the projects and resistance movements were systematized. One of the results was the identification of numerous processes of community resistance in defense of the rivers, widely distributed throughout the country’s different regions. Proof of that is the fact that many projects about to be built have been stopped due to those resistance movements, especially in the last two decades. Those struggles gave rise to a nationwide social movement in defense of the rivers, thus positioning the communities and their organizations as social actors in a field that had historically excluded them from decision making.Main Ideas: Research paper that analyzes, from a geographic perspective, the tension existing between hydroelectric expansion and community resistance movements in defense of the rivers of Costa Rica. Due to these resistance movements, a nationwide social movement in defense of the rivers has arisen in the last two decades., En Costa Rica, la mayor parte de la energía eléctrica generada proviene de plantas hidroeléctricas. No obstante, estas han traído consigo fuertes impactos socioambientales, provocando conflictos en decenas de comunidades del país. El artículo analiza la tensión entre la expansión de proyectos hidroeléctricos y las resistencias comunitarias en defensa de los ríos en Costa Rica, desde una perspectiva geográfica. Por tanto, se discuten e interpretan estos conflictos a través del mapeo de las plantas hidroeléctricas en operación, así como los núcleos de resistencia comunal frente a aquellas, a escala nacional. Para ello, se consultaron y combinaron diversos tipos de fuentes y se realizó una sistematización de dichos proyectos y resistencias. Entre los resultados se identificaron numerosos procesos de resistencia comunal en defensa de los ríos, ampliamente distribuidas por diferentes regiones del país. Muestra de ello es que muchos proyectos, que estaban planeados para ser construidos, fueron detenidos por estas resistencias, sobre todo en las últimas dos décadas. A raíz de estas luchas, se ha conformado un movimiento social en defensa de los ríos a escala nacional, posicionando a las comunidades y sus organizaciones como actores sociales y políticos en un campo que históricamente les había excluido de la toma de decisiones.Ideas destacadas: artículo de investigación que analiza la tensión existente entre la expansión hidroeléctrica y las resistencias comunitarias en defensa de los ríos en Costa Rica, desde una perspectiva geográfica. A raíz de estas resistencias, se ha conformado en las últimas dos décadas un movimiento social en defensa de los ríos a escala nacional., Na Costa Rica, a maior parte da energia elétrica gerada provém de usinas hidrelétricas. Contudo, estas têm trazido consigo fortes impactos socioambientais, o que provoca conflitos em dezenas de comunidades do país. Este artigo analisa a tensão entre a expansão de projetos hidrelétricos e as resistências comunitárias em defesa dos rios na Costa Rica, sob uma perspectiva geográfica. Portanto, são discutidos e interpretados esses conflitos por meio do mapeamento das usinas hidrelétricas em operação, bem como dos núcleos de resistência comunal ante aquelas, a escala nacional. Para isso foram consultadas e combinadas diferentes fontes de informação e realizada uma sistematização desses projetos e resistências. Entre os resultados, foram identificados numerosos processos de resistência comunal em defesa dos rios, amplamente distribuídas por diferentes regiões do país. Mostra disso é que muitos projetos de construção de usinas foram detidos por essas resistências, principalmente nas últimas duas décadas. Devido a essas lutas, conformou-se um movimento social em defesa dos rios no âmbito nacional, posicionando as comunidades e suas organizações como atores sociais e políticos em um campo que, historicamente, estavam excluídos da tomada de decisões.Ideias destacadas: artigo de pesquisa que analisa a tensão existente entre a expansão hidrelétrica e as resistências comunitárias em defesa dos rios na Costa Rica, sob uma perspectiva geográfica. Devido a essas resistências, conformou-se, nas últimas duas décadas, um movimento social em defesa dos rios em todo o país.
- Published
- 2020
39. Generation and investigation of a parallel-plate DBD driven at 1.6 MHz with flowing helium
- Author
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Anghel, S.D.
- Subjects
- *
DIELECTRICS , *HELIUM , *ELECTRIC circuits , *ATMOSPHERIC pressure , *ELECTRIC potential , *ELECTRODES , *EMISSION spectroscopy - Abstract
Abstract: The development of a new driven circuit that can drive a parallel-plate dielectric barrier discharge with flowing helium at atmospheric pressure is presented. The operating principle is based on the capability of a Tesla coil to generate high voltages with high oscillating frequencies. The discharge is generated inside a one open end parallelepipedic plasma chamber made of glass, using two outside parallel-plate electrodes. Depending on the helium flow-rate the plasma has three developing stages. In the homogeneous developing stage (1 l/min helium flow-rate) the plasma is characterized by using an electric model and based on its emission spectrum. [Copyright &y& Elsevier]
- Published
- 2011
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40. Generation and Electrical Diagnostic of an Atmospheric-Pressure Dielectric Barrier Discharge.
- Author
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Anghel, Sorin Dan
- Subjects
- *
ELECTRIC discharges , *ATMOSPHERIC pressure , *PLASMA generators , *ELECTRIC transformers , *ELECTRIC circuits , *DIELECTRICS , *MATHEMATICAL models , *ELECTRIC charge , *PLASMA diagnostics - Abstract
In this paper, the author develops a method of generation and characterization using an electrical model of a dielectric barrier discharge at atmospheric pressure. The principle of plasma generation is based on the resonant behavior of the secondary circuit of a modified flyback transformer, with the working frequency being 48 kHz. The plasma chamber is made of glass, and the working gas is helium with a flow rate of 0.44 L/min. The study refers to the homogeneous stage of the discharge which is characterized by a maximum power density of 6.4 \W/cm^3, electron current densities lower than 1.23 \mA/cm^2, and electron number densities in the range of 7.5 \cdot 10^8 to 2.7 \cdot 10^9\ \cm^-3, depending on the dc supply voltage. The gas temperature is slightly higher than the ambient one, with the plasma being nonaggressive with thermosensitive materials. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
41. ELECTRIC AND THERMAL CHARACTERIZATION OF INORGANIC SUPERCAPACITORS.
- Author
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PUşCAş, A. M., Carp, M. C., Borza, P. N., and Coquery, G.
- Subjects
- *
SUPERCAPACITORS , *ELECTRIC discharges , *ELECTRIC charge , *DIRECT currents , *ELECTRIC resistance , *ELECTRIC capacity - Abstract
Supercapacitors represent an alternative for the actual storage devices being able to provide high power density. The present paper is focused on characterizing the inorganic aqueous stacked supercapacitors. DC charge/discharge method was used to determine the dependency between the electric series resistance, capacitance and temperature. Electric impedance spectroscopy method was used to determine the variation with frequency of the real and imaginary part of the impedance. Based on the experiments an electric model was developed. The results of the simulations are compared with the experiments and the results are interpreted and discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2010
42. Forward modeling of different types of landslides with multi-electrode electric method.
- Author
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Guo, Xiujun, Huang, Xiaoyu, and Jia, Yonggang
- Abstract
Multi-electrode Electric Method (MEM) is an effective tool in landslide survey. A suitable working scheme in-situ and the corresponding data interpretation approach are the fundamentals for obtaining believable results. Finite element 2D forward modeling was conducted on four types of standard electric models; respectively named the homogeneous soil landside, bedding landside, sliderock landside, and beveling landside; under the utilizations of four different types of electrode arrays; respectively namely the Wenner array, Schlumberger array, dipole-dipole array and pole-pole array. The capacities of different arrays and the resistivity responses of different types of sliding faces were determined based on the resultant standard electric profiles. An innovative data processing procedure called the ratio parameter method was proposed for locating sliding faces under complex geological conditions. A series of case histories for landside survey were given. [ABSTRACT FROM AUTHOR]
- Published
- 2005
- Full Text
- View/download PDF
43. Control of a Traction/Charging Structure for a Hybrid Electric Vehicle
- Author
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Aghaei Hashjin, Saeid, UL, Thèses, Groupe de Recherche en Energie Electrique de Nancy (GREEN), Université de Lorraine (UL), ESME Sudria [Paris], Université de Lorraine, Babak Nahidmobarakeh, and El Hadj Miliani
- Subjects
Modèle électrique ,[SPI.AUTO] Engineering Sciences [physics]/Automatic ,Electric model ,[SPI.NRJ]Engineering Sciences [physics]/Electric power ,Moteur électrique ,Electric machine ,Commande sans capteur ,Sensorless control ,Model-free control ,Electric vehicle ,Véhicule électrique ,[SPI.AUTO]Engineering Sciences [physics]/Automatic ,[SPI.NRJ] Engineering Sciences [physics]/Electric power - Abstract
The electrification of the transportation is one of the relevant solutions to reduce greenhouse gas emissions. Indeed, new European standards impose increasingly restrictive limits on CO2 emissions per km. This is an important industrial issue for automobile manufacturers. Therefore, the industries are moving towards hybrid and electric vehicles in which an electric traction chain is present. This consists of an electrical machine, powered by a static power electronic converter connected to an electrical energy source and storage elements. For more than two decades, different topologies have been studied for electric traction and several solutions have been marketed. These products are increasingly light, reliable and efficient while respecting the constraints of the automobile manufacturers on the costs. This thesis focuses on improving the reliability of electromechanical energy conversion chains. The objective of the thesis is to continue the development of new actuator control laws ensuring better reliability of the traction chain. With this in mind, reducing the number of sensors in control of the conversion chain will be considered. In fact, there are already current sensors in traction chains. However, these generate significant additional costs because of their frequent failures and the need for replacement. Thus, current sensorless control of the AC drive systems allows the elimination of the sensors of the stator of the machine and therefore to avoid their cost. In this thesis, the model-free adaptive controller (MFAC) is presented to be used in the control of the conversion chain to reduce the number of sensors. In this regard, MFAC is used in two different approaches. First, it is used for controlling a WRSM system, with and without additional current sensors. Then, it is used for the control of the power converters used in the conversion chain. The experimental results, obtained on a test bench built in the laboratory, are conclusive in transient and steady-state: the unmeasured currents are converged with a satisfying precision for an automotive application and allow performing a current sensorless control of the machine. In addition, a satisfactory performance of MFAC is also obtained for controlling the power converters with only using one voltage sensor., L’électrification des moyens de transport est considérée comme l’une des solutions pertinentes pour réduire les émissions des gaz à effet de serre. En effet, les nouvelles normes européennes imposent des limites de plus en plus restrictives sur les émissions de CO2 par km. Ceci est un enjeu industriel important pour les constructeurs d’automobiles. Par conséquent, ces derniers s’orientent vers les véhicules hybrides et électriques dans lesquels une chaine de traction électrique est présente. Celle-ci est constituée d’une machine électrique, alimentée par un convertisseur statique d’électronique de puissance connecté à une source d’énergie électrique et des éléments de stockage. Depuis plus de deux décennies, différentes topologies ont été étudiées pour la traction électrique et plusieurs solutions ont été commercialisées. Ces produits sont de plus en plus légers, fiables et efficaces tout en respectant les contraintes des constructeurs d’automobile sur les coûts. Cette thèse s’inscrit sur l’amélioration de la fiabilité des chaînes de conversion d’énergie électromécanique. Le travail de thèse a pour objectif de poursuivre le développement de nouvelles lois de commande d’actionneur assurant une meilleure fiabilité de la chaîne de traction. Dans cette optique, réduire le nombre de capteurs de la chaîne de conversion dans la commande sera envisagée. En effet, il existe déjà des capteurs de courant dans les chaînes de traction. Cependant, ceux-ci engendrent des surcoûts importants à cause de leurs défaillances fréquentes et la nécessité de remplacement très couteuse. Ainsi l’étude réalisée de commande de machine synchrone à griffes sans capteur de courant permet la suppression des capteurs du stator de la machine et donc de s’affranchir de leur coût. Dans cette thèse, le model-free adaptive Controller (MFAC) est présenté pour être utilisé dans le contrôle de la chaîne de conversion pour réduire le nombre de capteurs. À cet égard, MFAC est utilisé dans deux approches différentes. Premièrement, il a été utilisé pour le contrôle d'un système WRSM, avec et sans capteurs de courant supplémentaires. Puis, il a été utilisé pour le contrôle des convertisseurs de puissance utilisés dans la chaîne de conversion. Les résultats expérimentaux, obtenus sur un banc de test réalisé en laboratoire, sont concluants en régime établi : les courants non mesurés sont contrôlés avec une précision satisfaisante pour une application automobile et permettent le contrôle sans capteur de courant de la machine. En plus, une performance satisfaisante du MFAC est également obtenue pour commander les convertisseurs de puissance avec un seul capteur de tension.
- Published
- 2020
44. Hydroelectric Projects and Community Resistance in Defense of the Rivers of Costa Rica: A Geographic Analysis
- Author
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Dany Villalobos Villalobos and Alberto Gutiérrez Arguedas
- Subjects
Costa Rica ,modelo eléctrico ,proyectos hidroeléctricos ,050204 development studies ,Geography, Planning and Development ,0507 social and economic geography ,lcsh:G1-922 ,Environmental Science (miscellaneous) ,Defensa comunitaria de los ríos ,Modelo elétrico ,Hydroelectricity ,Electric model ,0502 economics and business ,Earth and Planetary Sciences (miscellaneous) ,National level ,Proyectos hidroeléctricos ,Social movement ,conflictos socioambientales ,Resistance (ecology) ,Socio-environmental conflicts ,05 social sciences ,Hydroelectric projects ,Defesa comunitária dos rios ,Conflictos socioambientales ,Modelo eléctrico ,Geography ,Economy ,Projetos hidrelétricos ,defensa comunitaria de los ríos ,Conflitos socioambientais ,050703 geography ,Community defense of rivers ,lcsh:Geography (General) - Abstract
Resumen En Costa Rica, la mayor parte de la energía eléctrica generada proviene de plantas hidroeléctricas. No obstante, estas han traído consigo fuertes impactos socioambientales, provocando conflictos en decenas de comunidades del país. El artículo analiza la tensión entre la expansión de proyectos hidroeléctricos y las resistencias comunitarias en defensa de los ríos en Costa Rica, desde una perspectiva geográfica. Por tanto, se discuten e interpretan estos conflictos a través del mapeo de las plantas hidroeléctricas en operación, así como los núcleos de resistencia comunal frente a aquellas, a escala nacional. Para ello, se consultaron y combinaron diversos tipos de fuentes y se realizó una sistematización de dichos proyectos y resistencias. Entre los resultados se identificaron numerosos procesos de resistencia comunal en defensa de los ríos, ampliamente distribuidas por diferentes regiones del país. Muestra de ello es que muchos proyectos, que estaban planeados para ser construidos, fueron detenidos por estas resistencias, sobre todo en las últimas dos décadas. A raíz de estas luchas, se ha conformado un movimiento social en defensa de los ríos a escala nacional, posicionando a las comunidades y sus organizaciones como actores sociales y políticos en un campo que históricamente les había excluido de la toma de decisiones. Ideas destacadas: artículo de investigación que analiza la tensión existente entre la expansión hidroeléctrica y las resistencias comunitarias en defensa de los ríos en Costa Rica, desde una perspectiva geográfica. A raíz de estas resistencias, se ha conformado en las últimas dos décadas un movimiento social en defensa de los ríos a escala nacional. Abstract Most of the electric power in Costa Rica comes from hydroelectric power plants, which have caused strong socio-environmental impacts and provoked conflicts in many of the country's communities. The article analyzes the tension between the expansion of hydroelectric projects and community resistance in defense of the rivers of Costa Rica, from a geographic perspective. To that effect, it discusses and interprets those conflicts by mapping the operating hydroelectric plants and the focal points of community resistance to them, at the national level. Different types of sources were consulted and combined, and the projects and resistance movements were systematized. One of the results was the identification of numerous processes of community resistance in defense of the rivers, widely distributed throughout the country's different regions. Proof of that is the fact that many projects about to be built have been stopped due to those resistance movements, especially in the last two decades. Those struggles gave rise to a nationwide social movement in defense of the rivers, thus positioning the communities and their organizations as social actors in a field that had historically excluded them from decision making. Main Ideas: Research paper that analyzes, from a geographic perspective, the tension existing between hydroelectric expansion and community resistance movements in defense of the rivers of Costa Rica. Due to these resistance movements, a nationwide social movement in defense of the rivers has arisen in the last two decades. Resumo Na Costa Rica, a maior parte da energia elétrica gerada provém de usinas hidrelétricas. Contudo, estas têm trazido consigo fortes impactos socioambientais, o que provoca conflitos em dezenas de comunidades do país. Este artigo analisa a tensão entre a expansão de projetos hidrelétricos e as resistências comunitárias em defesa dos rios na Costa Rica, sob uma perspectiva geográfica. Portanto, são discutidos e interpretados esses conflitos por meio do mapeamento das usinas hidrelétricas em operação, bem como dos núcleos de resistência comunal ante aquelas, a escala nacional. Para isso foram consultadas e combinadas diferentes fontes de informação e realizada uma sistematização desses projetos e resistências. Entre os resultados, foram identificados numerosos processos de resistência comunal em defesa dos rios, amplamente distribuídas por diferentes regiões do país. Mostra disso é que muitos projetos de construção de usinas foram detidos por essas resistências, principalmente nas últimas duas décadas. Devido a essas lutas, conformou-se um movimento social em defesa dos rios no âmbito nacional, posicionando as comunidades e suas organizações como atores sociais e políticos em um campo que, historicamente, estavam excluídos da tomada de decisões. Ideias destacadas: artigo de pesquisa que analisa a tensão existente entre a expansão hidrelétrica e as resistências comunitárias em defesa dos rios na Costa Rica, sob uma perspectiva geográfica. Devido a essas resistências, conformou-se, nas últimas duas décadas, um movimento social em defesa dos rios em todo o país.
- Published
- 2020
45. Power estimation of a current supplied DBD considering the transformer parasitic elements
- Author
-
Rafael Diez, Arnold Wiesner, Hubert Piquet, Vanesa Rueda, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Pontificia Universidad Javeriana (COLOMBIA), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Laboratoire Plasma et Conversion d'Energie - LAPLACE (Toulouse, France), Pontificia Universidad Javeriana (PUJ), Groupe ENergie Electrique et SYStémique (LAPLACE-GENESYS), LAboratoire PLasma et Conversion d'Energie (LAPLACE), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, and Institut National Polytechnique de Toulouse - INPT (FRANCE)
- Subjects
Dielectric Barrier Discharge ,Energie électrique ,Materials science ,Electric Discharge Power Supply ,02 engineering and technology ,Dielectric barrier discharge ,Plasma sources ,01 natural sciences ,7. Clean energy ,Capacitance ,Industrial and Manufacturing Engineering ,010305 fluids & plasmas ,law.invention ,Current Mode ,Parasitic capacitance ,law ,Electric model ,0103 physical sciences ,0202 electrical engineering, electronic engineering, information engineering ,Waveform ,Electrical and Electronic Engineering ,Transformer ,Dielectric barrier discharge (DBD) ,business.industry ,020208 electrical & electronic engineering ,[SPI.NRJ]Engineering Sciences [physics]/Electric power ,Electrical engineering ,Current source ,Inductance ,Control and Systems Engineering ,DBD ,Electric power ,business - Abstract
International audience; Power estimation of a DBD device supplied by a current source converter is studied in this article, pointing out the prominent contribution of the transformer parasitic elements. The impact of the stray capacitance and magnetizing inductance is stated and an iterative method that estimates the electrical power and DBD waveforms is presented. Results show that the magnetizing inductance can enhance the electrical power without changing the current ratings of the converter and that the stray capacitance must be minimized. Moreover, the experimental results reveal the need for a better DBD model to properly estimate the power. In consequence, an improved model is proposed and validated using a DBD excimer lamp in a wide range of electrical operating conditions.
- Published
- 2019
- Full Text
- View/download PDF
46. Diseño en SolidWorks de plataforma del sistema cardiovascular para ensayo de robots de navegación autónoma
- Author
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Nuevo-Gallardo, Cristina, Traver, José Emilio, Tejado, Inés, Prieto-Arranz, Javier, López, Miguel A., Vinagre, Blas M., Nuevo-Gallardo, Cristina, Traver, José Emilio, Tejado, Inés, Prieto-Arranz, Javier, López, Miguel A., and Vinagre, Blas M.
- Abstract
[Resumen] Este artículo presenta una plataforma de simulación del sistema cardiovascular (SCV) diseñada en el software de diseño 3D SolidWorks, basada en un modelo hidráulico que describe la dinámica de contracción del corazón y de la arteria carótida izquierda, así como el carácter cíclico y autónomo del primero, previamente validado mediante la herramienta Matlab/Simulink. La plataforma diseñada en SolidWorks tiene como objetivo el desarrollo de experimentos y ensayos con robots nadadores de pequeñas dimensiones, permitiendo emular las condiciones en las que se encontrarían estos robots navegando por el sistema circulatorio humano., [Abstract] This article presents an experimental platform of the cardiovascular system (CVS) designed in Solidworks and based on an electric model which describes the contraction dynamics of the heart as well as its cyclic and autonomous caracteristics. Depart from this model, previously generalized to include the dynamics of the left common carotid artery, a hydraulic model was developed emulating the behaviour of the CVS in that zone, been validated by the Matlab/Simulink tool. The designed platform is a representation of this hydraulic model, which objective is to test swimming robots of small dimensions and to allow the simulation of the conditions in which these robots would navigate in the human circulatory system.
- Published
- 2019
47. An electric model of a vapour anode, multitube alkali–metal thermal-to-electric converter.
- Author
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Tournier, J.-M. and El-Genk, M.S.
- Abstract
A two-dimensional electric model of vapour anode, multitube alkali–metal thermal-to-electric conversion (AMTEC) cells was developed. These cells are being developed to power the Pluto/Kuiper Express and Europa Orbiter spacecrafts, at NASA which are scheduled for launch early in the next century. Model results of several cells tested at the Air Force Research Laboratory showed that electric losses in the current collector networks and the connecting leads were negligible. The charge-exchange polarization/concentration losses in the TiN electrodes were the major losses, amounting to 25–50% of the cell's total theoretical power, while the contact losses and the beta″-alumina solid electrolyte ionic losses amounted to less than 16% of the cell theoretical power. Results also showed that a cell with advanced Rh
2 W electrodes could have delivered from 14% to 25% more electrical power. [ABSTRACT FROM AUTHOR]- Published
- 1999
- Full Text
- View/download PDF
48. Systemic analysis of the evolution of the components of the electrical model of the students: Control, structures and processes
- Author
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Cristian Merino, Patricia Moreira, and Ainoa Marzabal
- Subjects
modelización ,lcsh:LC8-6691 ,estructura ,modelo eléctrico ,lcsh:Special aspects of education ,model elèctric ,modelling ,electric model ,structure ,control ,process ,modelització ,procés ,proceso ,lcsh:L ,lcsh:Education - Abstract
Els currículums de Ciències assenyalen la rellevància de comprendre els fenòmens elèctrics, a causa de les múltiples aplicacions tecnològiques actuals basades en l'electricitat. No obstant això, els estudiants tenen dificultats per comprendre la naturalesa electromagnètica de la matèria, i es requereixen evidències empíriques de les formes en què les idees dels estudiants es van transformant a mesura que adquireixen experiència i coneixement conceptual sobre electricitat. Aquest estudi es focalitza en l'anàlisi de les explicacions d'estudiants de secundària sobre fenòmens elèctrics, amb el propòsit de caracteritzar l'evolució dels seus models expressats durant una seqüència didàctica basada en fenòmens d'electrització. La proposta d'anàlisi qualitativa, des d'una perspectiva sistèmica, identifica els components d'estructura, procés i control referits pels 30 estudiants de la mostra, en les explicacions de cinc fenòmens observats, caracteritzant l'evolució del model elèctric dels estudiants. Els nostres resultats mostren que les trajectòries d'aprenentatge dels estudiants són poc convergents i presenten discontinuïtats. La descomposició del model elèctric ens ha permès evidenciar que els estudiants construeixen models limitats pels processos observats, i tenen dificultats per transitar al nivell microscòpic, el que pot contribuir a orientar la selecció de fenòmens per part dels professors per aconseguir processos de modelització més efectius., Science curricula indicate the relevance of understanding electrical phenomena, due to the multiple current technological applications based on electricity. However, students have difficulty understanding the electromagnetic nature of matter, and empirical evidence is required of the ways in which students' ideas are transformed as they gain experience and conceptual knowledge about electricity. This study focuses on the analysis of secondary school students' explanations of electrical phenomena, with the purpose of characterizing the evolution of their models expressed during a didactic sequence based on electrification phenomena. The proposal of qualitative analysis, from a systemic perspective, identifies the structure, process and control components referred by the 30 students of the sample, in the explanations of five observed phenomena, characterizing the evolution of students' electrical model. Our results show that the learning trajectories of students are not convergent and present discontinuities. The decomposition of the electrical model has allowed us to show that students build models limited by the observed processes, and have difficulties to move to the microscopic level, which can help to guide the selection of phenomena by teachers to achieve more effective modeling processes., Los currículos de Ciencias señalan la relevancia de comprender los fenómenos eléctricos, debido a las múltiples aplicaciones tecnológicas actuales basadas en la electricidad. Sin embargo, los estudiantes tienen dificultades para comprender la naturaleza electromagnética de la materia, y se requieren evidencias empíricas de las formas en que las ideas de los estudiantes se van transformando a medida que adquieren experiencia y conocimiento conceptual sobre electricidad. Este estudio se focaliza en el análisis de las explicaciones de estudiantes de secundaria sobre fenómenos eléctricos, con el propósito de caracterizar la evolución de sus modelos expresados durante una secuencia didáctica basada en fenómenos de electrización. La propuesta de análisis cualitativo, desde una perspectiva sistémica, identifica los componentes de estructura, proceso y control referidos por los 30 estudiantes de la muestra, en las explicaciones de cinco fenómenos observados, caracterizando la evolución del modelo eléctrico de los estudiantes. Nuestros resultados muestran que las trayectorias de aprendizaje de los estudiantes son poco convergentes y presentan discontinuidades. La descomposición del modelo eléctrico nos ha permitido evidenciar que los estudiantes construyen modelos limitados por los procesos observados, y tienen dificultades para transitar al nivel microscópico, lo que puede contribuir a orientar la selección de fenómenos por parte de los profesores para lograr procesos de modelización más efectivos.
- Published
- 2019
49. Novel method for the parameterization of a reliable equivalent circuit model for the precise simulation of a battery cell's electric behavior.
- Author
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Bruch, Maximilian, Millet, Lluis, Kowal, Julia, and Vetter, Matthias
- Subjects
- *
LITHIUM-ion batteries , *ELECTRIC cells , *ELECTRIC batteries , *PARAMETER identification , *PARAMETERIZATION , *LITHIUM cells - Abstract
This article presents a novel approach to extract the equivalent circuit model parameter from a pulse test. The presented results corroborate that this novel heuristic methodology can very accurately fit the voltage response of the battery, while drastically reducing the dependence of the parametrization on set boundary conditions and initial guess values. The method's robustness is verified by fitting the voltage response of a mock battery model with pre-defined parameters. It could be shown that the suggested method is able to precisely extract the set parameters from the simulated voltage. Furthermore, the model values obtained from the test of a lithium ion battery cell correlate with physical parameter and other investigation methods like the calculation of the distribution of relaxation times (DRT). As a result, an accurate equivalent circuit model of the cell was created. The restriction as to universal validity of the empirical equivalent circuit model was significantly reduced by limiting the voltage of the RC element with highest time constant. Finally, a robust battery cell model with only a minor root-mean-square error of 1.30% was obtained. A new method for the precise parameterization of an equivalent circuit model from pulse tests is presented. The robustness of such equivalent circuit models is increased by limiting the voltage of the RC element with the highest time constant. Overall, a precise, reliable model of a lithium-ion battery cell is created. • Pulse characterization of a lithium-ion cell. • Process for equivalent circuit model parameter identification. • Precise electric model of a battery cell. • Improvement of the equivalent circuit models robustness. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
50. Análisis de Flujos de Carga del Sistema CHEC Ante la Incorporación Masiva de Fuentes de Generación
- Author
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Monsalve Zapata, Mauricio and Carvajal Quintero, Sandra Ximena (Thesis advisor)
- Subjects
Diagnostico ,Generación de energía ,Demanda de energía eléctrica ,Electric power - demand ,Condiciones eléctricas ,Risaralda (Colombia - departamento) ,Flujos de carga ,Inversión ,Generation projects ,Electrical conditions ,Modelo eléctrico ,Electric model ,62 Ingeniería y operaciones afines / Engineering ,Load flows ,Diagnosis ,Proyectos de generación ,Planning methodologies ,Caldas (Colombia - departamento) ,Investment ,Metodologías de planeación ,Power generation - Abstract
En este documento se presenta los flujos de carga en el sistema eléctrico CHEC para los años 2017 y 2022, en demanda máxima y mínima con escenario de generación máxima y mínima, se tendrán en cuenta las exigencias tanto de la CREG como de las UPME. Se lleva a cabo simulaciones que involucra la generación aprobada por la UPME, la que se encuentra revisando el OR (estudios de conexión) y la futura a desarrollar (han manifestado conectarse al sistema), donde estas se involucran en un modelo eléctrico que represente la importancia de cada zona de Caldas y parte de Risaralda, de esta forma se realiza simulaciones por medio del software DigSilent, Power Factory, lo que permite definir las condiciones eléctricas del sistema en corto, mediano y largo plazo. Se aplican metodologías de planeación de la infraestructura y la valoración de sus activos basados en la resolución 015 de 2018 y de esta manera determinar que equipos se deben cambiar en el sistema eléctrico del OR CHEC. Adicionalmente las conexiones proyectadas cuentan con parámetros, capacidad de generación y años de entrada de puesta en operación, lo que permite llevar a un modelo datos reales, con el fin de obtener resultados muy aproximados en un horizonte de análisis. Aparte de los parámetros mencionados se cuenta con información de demanda de cada zona y del Sistema Interconectado Nacional, proyectos futuros de transmisión como de generación. Con el desarrollo de la tesis se obtienen resultados y conclusiones. El aporte principal es entregar un diagnóstico que dé una visión acerca de las necesidades y requerimientos del sistema eléctrico que lleve a tomar decisiones más acertadas y con menores márgenes de error en cuanto a la inversión Abstract: This document analyzes the load flows in the CHEC electric system for the years 2017 and 2022, in maximum and minimum demand with maximum and minimum generation scenario, as well as the requirement of the CREG and the UPME. Simulations are carried out involving the generation approved by the UPME, which is reviewing the OR (connection studies) and the future to develop (have manifested to connect to the system), when these are involved in an electric model that represents the importance of each area of Caldas and part of Risaralda, in this way simulations are carried out using software DigSilent Power Factory, which allows defining the electrical conditions of the system in the short, medium and long term. This analysis allows to apply the measures of infrastructure planning and the valuation of assets in resolution 015 of 2018 and in this way determine which equipment should be changed in the electric system of the CHEC OR. The projected connections have parameters, generation capacity and years of entry into operation, which makes it possible to carry out a real data model, in order to obtain very approximate results in an analysis horizon. Other parameters related to the information of each zone and the National Interconnected System, future transmission and generation projects. With the development of the thesis results and conclusions are obtained. The main contribution is to deliver a diagnosis of a vision about the needs and requirements of the electrical system that leads to more accurate decisions and with lower margins of error in terms of investment Maestría
- Published
- 2018
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