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In this article, a novel topology generalization of a current source converter (CSC) that allows controlling of multiple single-phase ac converters independently sharing the same dc-bus, with the advantage of having a reduced number of conducting switches and a lower dc-bus current, is presented. A conventional $n$ -output/port single-phase CSC that uses the same dc-bus needs to have $n$ H-bridge converters connected in series, which means that it always has $2 n$ conducting switches. The new topology allows generating any $n$ ac output currents always having only $(n+1)$ conducting switches in a switching period. This represents $(1-{1}/{n})\!\cdot 50$ % less conduction losses when compared with the equivalent conventional multiport single-phase CSC. A scalar pulsewidth modulation to control the converters with switching optimization and its generalization is also presented. Details of topology, control strategy, and modulation are presented. Simulation and experimental results are provided to validate the theoretical approach.

The constant growth of distributed energy resource (DER) in the electric power system (EPS) is a reality on account of some aspects, for example, technical, financial, environmental. The insertion of DERs can be positive, providing ancillary services, for example, harmonic mitigation, or negative, causing overvoltage, depending on the proper control and the characteristics of the grid. This paper proposes a pq‐based control strategy for distributed generation, wherein the studied system is composed by a photovoltaic DER and a three‐phase converter for processing the generated power and providing ancillary services (ASs) to a three‐wire EPS. The power control is based on the power balance between the grid and the converter. Besides supplying active and reactive power, the proposed strategy can provide ASs by controlling the grid currents from a pq transformation. Some advantages over other solution can be mentioned, such as reduced sensor number and instantaneous control response. In addition, neither additional harmonic‐extraction method nor a phase‐locked loop is required. To validate this study and theoretical considerations, simulation results are presented and evaluated. From tests in a downscaled laboratory setup, experimental results are also presented to verify the effectiveness of the proposed control strategy.

Climate neutrality coupled with an overall positive ecological footprint is still a distant dream for new construction. The German building sector is directly and indirectly responsible for about 40% of all German CO2 emissions and has so far failed its CO2 reduction goals. For the German building sector, the key to climate neutrality lies not only within new construction but in its existing building fabric. The embodied carbon of new construction needs be reduced as well as the amount of new construction itself. Hence the reuse of buildings and the extension of their life cycles is a crucial factor in reducing CO2 emissions and resource consumption. In this paper we present three of our projects (from the office Sauerbruch Hutton), highlighting not only the potentials but also the problems that planners face with existing buildings. Additionally, our project based LCA analysis showcases that retrofitting can have a much smaller CO2 footprint than a new building.

Atualmente, o armazenamento de energia apresenta-se como fundamental no que se refere ao suprimento e manutenção da energia elétrica. Isso se deve, de modo principal ao fato de que sistemas de armazenamento de energia (ESS - Energy Storage System) podem proporcionar estabilidade da rede, aumento da inserção de recursos de energias renováveis, conservação de recursos energéticos fósseis e reduzir o impacto ambiental de geração de energia. Nesse sentido, este trabalho apresenta uma revisão sobre diferentes sistemas de armazenamento, bem como tecnologias associadas a esse sistemas. Fornecendo assim maior enfoque aos ESS que são compostos por baterias. Desse modo, o estudo foi fomentado através da análise científica de diversas referências que abordam a temática de armazenamento. Em que, por meio desses estudos, foi possível obter a caracterização de tais tecnologias sob a perspectiva de funcionamento, de modo a fornecer uma vis ̃ao mais clara sobre a aplicabilidade de ESS para diferentes fins.

With the recent push for renewable energy several former consumers units now have energy generation capabilities. While this approach is beneficial in general, it also poses new challenges for cooperation and grid stability. The new smartgrid now needs bidirectional power flow, data communication, and intelligent controls in order to ensure reliable operation. Voltage sensing plays a key role, capacitive voltage transformers have been demonstrated useful for high- voltage (100kV+), but have not yet been discussed for low (220V) and medium (13kV) voltage. This paper proposes a simplified capacitive voltage divider circuit for low-voltage measurement. Mathematical modelling is used for steady-state operation, circuit design, and sensitivity to analysis. Monte-Carlo simulations are employed to verify the effect of component tolerances, indicating under 0.7dB gain, and 0.03° error at fundamental frequency. Experimental validation is performed at low-voltage levels (127V), indicating 0.5 dB magnitude and 0.3° phase deviation at fundamental frequency. Performance is also validated from 60Hz to the 50th harmonic, showing 20° phase deviation at the higher order harmonics (16th and up). From the obtained results it is expected that the sensor is sufficient for voltage quality measurements, but should be software-corrected if power measurement is required at the high-order harmonics.

Neste trabalho, é realizada a análise do fornecimento de serviços ancilares por um sistema de armazenamento de energia baseado em baterias à um sistema de distribuição, utilizando um conversor trifásico bidirecional. Os serviços ancilares incluem a compensação de harmônicos, correção do fator de potência e a injeção de potência ativa pelo sistema de armazenamento de energia baseado em baterias em horários de ponta e fora de ponta, visando a minimização dos custos com demanda e a redução do fluxo de potência. Para realizar a redução de harmônicos na corrente da rede, foi implementado o controle proporcional-integral, utilizando a corrente medida na rede. O controle da corrente do sistema de armazenamento também foi realizado pelo mesmo controlador, onde foi necessário apenas a aquisição da corrente na bateria, permitindo também o controle de seu estado de carga. O gerenciamento de energia, foi realizado de acordo com a análise de curva de carga do sistema de distribuição em estudo e com o estado de carga do sistema de armazenamento, onde foram definidos o período de ponta e fora de ponta em que a bateria seria carregada e descarregada.

New questions related to the quality of the grid energy and reliability with the insertion of distributed energy resource (DER)s, and, new problems may arise as voltage variations by load variations and the determination of current limits. Thus, the control of the DER units should be cooperative and active to support the voltage regulation, as the frequency is still controlled from the main grid. Most of control strategies applied for distributed generation systems (DGS) have relied on power controls based on active (P) and reactive reactive (Q) power droop to achieve. This paper shows a comparative study between the classic PQ droop control and a accurate IV droop control.

Unconventional energy sources such as wind, solar and biomass represents more and more an alternative in substitution of conventional energy sources. In effect, many studies still need to be done to clearly identify the impacts that the insertion of distributed generation (DG) sources represent in the power grid. In this paper, an analysis of the impact of the distributed generation (DG) insertion in the electrical grid is realized, based on impedance matrix, grid voltage and power factor (PF). Benchmarks were created to relate the sensibility in a point common coupling (PCC) to the DG insertion. Preliminary results show that sensibility does not change with the load or the PF of the DG.

With increasing use of intermittent renewable energy sources, energy storage is needed to maintain the balance between demand and supply. The renewable energy sources, e.g. solar and wind energy sources, are characterized by their intermittent generation, causing fluctuations in power generation, and, similarly, demand may vary. There may be fluctuations in power generation, and, similarly, demand may vary. Then, for these new sources become completely reliable as primary energy sources, energy storage is a crucial factor. This work uses real-time simulation to analyze the impact of battery-based energy storage systems on electrical systems. The simulator used is the OPAL-RT/5707™ real-time simulator, from OPAL-RT Technologies company. The simulated system consists of a three-phase inverter connected to a BESS (battery energy storage system) and to the electrical grid with variable loads. The obtained results from real-time simulations prove its effectiveness for this type of analysis and open the possibility to perform PHIL (power hardware in the loop) simulations.

The home automation systems represent an advance in people's practicality and comfort. The use of smartphones and the integration with the main systems in home turns assignments simpler. For example, this is possible due to the use of devices which receives the command from the user and delivers to the other systems of the home, also called actuators. However, in a way to compensate this kind of investment, is interesting that exists an economy associated in use of the automation. In this case, is presented in this paper an actuator based on the combination of optocoupler and TRIAC, with low cost and focus on the decrease of inrush current present in the transient stage of lamps in general. For comparison with an actuator based on an electromechanical relay, prototypes are made and experimental tests realized for verification of results, using three different types of lamps: incandescent, fluorescent and LED. The maximum reduction of inrush current obtained was 97.78 %, in the fluorescent lamp.

According to the International Energy Agency/USA (lEA): “a smart grid (SG) is an electricity grid that uses digital technology to monitor and manage the transportation of electricity from all sources of generation, finding a variety of demands and users. These networks will be able to coordinate the needs and capabilities of all generators, operators, end-users and stake holders of the electricity market in order, to optimize the use and operation of the assets in the process, minimizing environmental costs and impacts while maintaining reliability, resilience and stability of the system”. The increasing need for more effective power electrical systems (generation, transmission and distribution) control has made the development of SG the main object of study for many researchers. In this context and looking for the integration and convergence of different systems to incorporate an infrastructure of a SG, this work designs and implements an flexible intelligent electronic device (lED). The proposed lED differs from the existing lEDs presenting a flexible capacity, as it can perform the acquisition of different variables (voltage, current, temperature, pressure, etc.) with different conditioning values, furthermore, the conditioning is carried out by software. The IED can operate as a smart meter, as a dynamic controller (local) and/or as a supervisory controller, thus improving the efficiency, reliabihty and security of the system. Other advantages of the proposed lED are: low cost, versatility (changes can be made by software), high processing capacity (ARM processor), communication features (hybrid network architecture (HNA)), easy integration (interoperability), easy maintenance (modularity) and scalability.

Lithium battery cells are commonly modeled using an equivalent circuit with large lookup tables for each circuit element, allowing flexibility for the model to match measured data as close as possible. Pulse discharge curves and charge curves are collected experimentally to characterize the battery performance at various operating points. It can be extremely difficult to fit the simulation model to the experimental data using optimization algorithms, due to the number of values in the lookup tables. This paper describes a detailed procedure of how estimate the battery model parameters using experimental data. the experiment is realized with a computer that realize the control of charge and discharge process sending SCPI commands via serial communication to the Four Quadrant Power Supply from Kepco Inc. with 100V and 10A as limits. The estimation of each battery model parameter is made to lithium-ion battery with a capacity of 20 Ah, and the presented methodology can be easily adapted to any type of battery. The mean objective of the results is estimate the battery parameters to posteriorly use the battery model to estimate the SoC by adaptive method. As results, after the estimation of each parameter, it is possible to observe the resistances exponential behavior, where they decrease as SoC decrease. As conclusions, this paper can contribute to the field of measurement of magnetic and non electric quantities, where it helps to determine the Battery Equivalent Circuit Model and its parameters.

State of Charge (SoC) is the most important parameter to be estimated on a Battery Management System (BMS). Improper SoC management can cause faster battery degradation, reduce its operational lifetime and, on extreme cases of overcharge, it may lead to an explosion. In addition, batteries are complex electrochemical systems, and both the electrical components and chemical reactions vary significantly with changes in temperature. In this paper, it is presented the effect of the temperature on the Lead Acid battery SoC estimation. The data collection was performed varying the battery temperature, under a range of 10oC to 70oC. To determine the model parameters from the used battery, several data acquisition was performed. To obtain the SoC estimation it was implemented the Extended Kalman Filter that provide satisfactory results. The simulated results were obtained using the MATLAB environment. To verify the effectiveness and the performance of the implemented Kalman Filter it was applied the EKF for estimate the SoC of a Lead Acid battery described in the Introduction Section. It is important to realize that is a comparative study and the only evaluation comparison with the SoC estimation that we can do uses the Open Circuit Voltage (OCV).

Objectives Objective and subjective evaluation of botulinum neurotoxin A (BoNTA) treatment for adductor type spasmodic dysphonia is presented. Therefore, a combinatorial approach based on patients’ and speech experts’ assessment of voice impairment, as well as on the acoustic analysis of spoken standardized text was performed. Study design Prospective clinical study. Materials and methods For 17 patients, the voice quality prior to and 4–8 weeks after BoNTA injection (9 transoral, 8 transcutaneous) was investigated. Voice Handicap Index-12 (VHI-12) questionnaires as well as ratings of the GRB (grade, roughness, breathiness) scale were analyzed. Moreover, objective parameters such as pure speech duration, local jitter, local shimmer and voice breaks were evaluated. Results The pre-post analysis of all patients revealed a significant reduction of the VHI-12 score, the jitter values and the number of voice breaks. Changes in speech duration and breathiness differed significantly for transoral vs. transcutaneous BoNTA injection. Conclusions We were able to correlate the questionnaire-based self-assessment with external evaluation of the speech roughness and with acoustic signal analysis parameters, in particular for the jitter. Our data indicated beneficial effects for transoral BoNTA application.

This paper proposes a technique for accelerating the convergence to the maximum power point of photovoltaic (PV) systems based on the model obtained from manufacturer's generator data. The influence of the temperature over the PV array performance is considered, and no measurement of solar radiation is required. Knowledge of the load model and expensive sensor circuitry are not necessary. The tracking speed is much faster than nonmodel-based techniques at the expense of an increase in the computational complexity. Simulation and experimental results are presented and demonstrate the feasibility of the proposed solution.

Expression of thioredoxin-1 (TXN) and CXCL9 is not restricted to THRLBCL macrophages, but may be observed in histiocytes and neoplastic (HRS) cells of EBV + mixed cellularity (MC) classical Hodgkin lymphoma (cHL) and nodular lymphocyte predominant HL. We aimed to validate and extend the above observations in 174 cHL patients evaluating the immunohistochemical expression of TXN, CXCL9 and IFN-γ. HRS-cell CXCL9 expression was higher in latent membrane protein-1 (LMP1)+, MC and Stage IV. TXN and CXCL9 expression by cHL histiocytes was more frequent in LMP1+, MC and older patients (only for CXCL9). TXN expression by HRS cells (≥80%) was independently associated with better failure-free survival. In conclusion, markers of TCHRLBCL histiocytes (TXN, CXCL9), as well as IFN-γ are also expressed by histiocyte subsets and neoplastic cells of cHL. The expression of some of them is more prominent in EBV + MC, but not restricted to this subtype. The prognostic implication of TXN needs further evaluation. © 2017 Informa UK Limited, trading as Taylor & Francis Group.

This paper proposes a practical method for characterization of photovoltaic (PV) systems under uniform radiation and under shading conditions, based on voltage and current graphics. A simple circuit to detect these shading conditions is projected to enhance the visualization of disturb caused by blocking one or more cells of the PV module. Therefore, this circuit is very interactive, because the curve changes instantly when the shading condition occurs. Thanks to it, this project is quite useful for educational purposes, in study of characterization of photovoltaic systems curves. The characteristic curves of the PV system under uniform radiation are necessary to compare with experimental results. Using an oscilloscope, the curves of a PV module under uniform radiation and partial shading are analyzed.

In the concept of Smart Grid (SG), reliable and real-time information becomes the key factors. Usually, the alternatives for data acquisition are based on proprietary solutions for dedicated systems using wired communication, cables and various kinds of sensors. The installation and maintenance of these systems are usually much more expensive than the cost of the sensors themselves. An alternative is using wireless sensor networks, which are driven by low cost, low power and multifunctional sensor nodes over a limited distance. This communication presents two quite significant problems: (1) energy consumption (battery lifetime); and (2) interference (data loss). This paper focus in evaluate efficient tests for wireless communication. In this way, identifying the most suitable for selecting wireless transceivers applied for Intelligent Electronic Devices (IED) in the Smart Grid concept.

Smart Grid (SG) can be defined as a modern electric power grid infrastructure for improved efficiency, reliability and safety, with smooth integration of renewable and alternative energy sources, through automated control and modern communications technologies. The increased need for more effective control on electrical power systems has led to the development and the increased research interest on SG. The construction of SG involves the positive transformation of traditional electricity networks, with one-way power flow, to a system with a new technology, by adding intelligent sensors, distributed generation and storage system, back-end information systems, smart meters and communications networks, to permit two-way power flow with communication and control. All this information should be obtained from the network. So, the development and implementation of Intelligent Electronic Device (IED) improves the efficiency, reliability and security of the electric power system. This paper presents the development of an IED, based on TivaC platform for Smart Grid applications, with high capacity processing, communication features, portability/versatility, low cost, easy integration (interoperability) and maintenance. For the communication the proposed IED uses the Hybrid Network Architecture (HNA) concept and open source programming.

This paper presents a low cost Battery Information System, based on intelligent modules to be embedded inside single battery cells. The module design is cost-optimized, including only minimal functionality to uniquely identify each cell, and measure voltage and temperature. Current measurement is accomplished be an addition module added to each series-connected battery stack, avoiding unnecessary cost of redundant current sensors. Data from several modules is aggregated via a time-triggered proprietary wireless network, and then relayed to a remote, centralized server over standard TCP/IP WiFi connection. The remote battery database is supposed to be installed at the battery manufacturer's server, and can potentially aggregate data from all manufactured batteries. Such an extensive database is expected to enable advanced analysis and modeling of batteries, as well as provide online monitoring and reporting services as an added value for customers.

Im vorliegenden Fallbericht wird von einem 24-jahrigen deutschen Soldaten berichtet, der in der Silvesternacht 2009/2010 im Kosovo-Auslandseinsatz durch ein vom Himmel gefallenes Vollmantelgeschos in Folge von Freudenschussen, sog. „happy shooting“, im Bereich der rechten Schulter verletzt worden ist.

Immunosuppressive treatment increases the risk of infection and malignancy in organ transplant recipients. We report on a 42-year-old male renal transplant recipient who lost his first graft after reduction of immunosuppressive treatment due to Kaposi sarcoma and who successfully underwent a second renal transplant 10 years later. The patient’s current treatment consists of low-dose prednisone, and the two antiproliferative immunosuppressants mycophenolate mofetil and rapamycin. 4.5 years after his second transplant, the serum creatinine is 1 mg/dl and the patient has no signs of recurrent disease.

Seit 1992 wird die Bundeswehr zu friedenserhaltenden und -sichernden Masnahmen auserhalb der Bundesrepublik Deutschland eingesetzt. Bei Auslandseinsatzen kamen bisher 83 Soldaten ums Leben, insgesamt 129 wurden durch Fremdeinwirkung verwundet (Stand 07.12.2009). Zur sanitatsdienstlichen Versorgung der Soldaten in Nordafghanistan betreibt die Bundeswehr in Mazar-i-Scharif ein Einsatzlazarett mit multidisziplinarem Leistungsspektrum, auserdem 2 Rettungszentren in Kunduz und Faizabad zur notfallchirurgischen Erstversorgung. In den Rettungszentren werden lebensrettende und stabilisierende Operationen durchgefuhrt, um die schnelle Evakuierung in eine Sanitatseinrichtung der nachsthoheren Versorgungsebene und schlieslich die Ruckfuhrung in das Heimatland zu ermoglichen. Dabei sieht sich der Militarchirurg mit vielfaltigen sowohl medizinischen als auch logistischen Herausforderungen konfrontiert. Eine Besonderheit ist das weltweit einsetzbare Marineeinsatzrettungszentrum (MERZ) zur sanitatsdienstlichen Versorgung maritimer Einsatzverbande, das containergestutzt an Bord eines Einsatzgruppenversorgers (EGV) betrieben wird. Die „schwimmenden Lazarette“ stellen im Rahmen der medizinischen (Notfall-)Versorgung bei der Planung und Durchfuhrung von Einsatzen in Seegebieten mit schwierigen Raum- und Zeitfaktoren ein unverzichtbares Element dar. Durch den besonderen Wirkverbund zwischen EGV und MERZ sind zudem Spezialoperationen, Evakuierungen und humanitare Einsatze bei kustennahen Naturkatastrophen moglich.

In this work it is presented a novel topology of Current Source Converter (CSC) that allows to control multiple single-phase AC converters independently sharing the same DC-bus, with the advantage of having a reduced number of conducting switches, less switching and a lower DC-bus current. A conventional n-output/port single-phase CSC that uses the same DC-bus needs to have n H-bridge converters connected in series, which means that it always has 2n conducting switches. This new topology allows to generate any n AC output current having always only (n + 1) conducting switches in a switching period, representing (1 − 1/n) ⋅ 50% less conducting losses comparing on the equivalent conventional multi-port single-phase CSC. It is also presented a Scalar Pulse Width Modulation (SPWM) to control the converters with switching optimization. Details of topology, control strategy and modulation are presented. Realtime simulation results are provided to validate the theoretical approach.