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The main contribution of this paper is to present a simple algorithm that theoretically and numerically assesses the switching angles of an inverter operated with the SPWM technique. This technique is the most widely used for eliminating harmonics in DC-AC converters for powering motors, renewable energy applications, household appliances, etc. Unlike conventional implementations of the SPWM technique based on the analog or digital comparison of a sinusoidal signal with a triangular signal, this paper mathematically performs this comparison. It proposes a simple solution to solve the transcendental equations arising from the mathematical analysis numerically. The technique is validated by calculating the total harmonic distortion (THD) of the generated signal theoretically and numerically, and the results indicate that the calculated angles produce the same distribution of harmonics calculated analytically and numerically. The algorithm is limited to single-phase inverters with unipolar SPWM. [ABSTRACT FROM AUTHOR]

Permanent magnet motors have become very important in recent years due to the popularization of electric vehicles in the context of the efforts to transition to zero-emission transportation. This has encouraged researchers and hobbyists to learn about electric motor design. However, designing electric motors is not a simple task, as the information to achieve it is not easily available to everyone and it is usually complicated to understand. For that reason, this paper presents the equations and a basic process to design radial flux surface-mounted PM synchronous motors. This design method is the result of combining and organizing information from previous publications to create a relatively simple design guide. The result is a table of equations and a series of general guidelines that were verified by designing and simulating a 500 W eight-pole 2.6 Nm average torque dual-rotor motor and a 20 W four-pole 106 mNm single-rotor motor. The simulations validated the equations and the design method presented in this paper to be used by those interested in the field of electric motors and vehicles; therefore, in the future, others may contribute with improvements, particularizations or optimizations of this methodology, or even create their own. [ABSTRACT FROM AUTHOR]

The main contribution of this paper is the assets of the current and voltage ripples in a buck converter with an LED load. The results indicate that the ripples are different and that it is possible to reduce the passive filter concerning the model of the LED as a simple resistance. The paper presents the design and simulation of a buck converter as a power supply for an LED lamp. Modeling the LED as a resistor and a voltage source (SVRM), the equations to calculate the components of the circuit using the SVRM model are presented, where the Fourier series and phasors are used to calculate the output filter. The equations are validated with SPICE simulations. The results indicate that the SVRM model for the LED load affects the calculation of the output filter of the buck converter as well as the voltage and current ripples, making it a more precise design alternative to the proposed development. [ABSTRACT FROM AUTHOR]

Currently, the design of resonant power converters has only been developed while operating in the steady state, while the design operating in the transient stage has not been considered nor reported. This paper is interested in testing the performance of the resonant circuits operating in the transient stage and finding applications where benefits can be obtained from this form of operation. One application in which it is possible to obtain benefits from designing resonant circuits in the transient state is in the area of frequency multiplication. Usually, to achieve frequency multiplication, it is necessary to resort to complex methods and special devices that increase the complexity of the design and the total cost of the circuit. This paper evaluates the performance of a series RLC resonant circuit operating in the transient stage and with an underdamped response acting as a frequency multiplier, where the oscillation frequency of the current in the resonant tank is "n" number of times the switching frequency of the square voltage source at the input with a duty cycle of D = 50%. To validate the analysis, a circuit was designed to deliver an output power of 30 watts to a resistive load, where the switching frequency of the square voltage source at the input was 500 kHz. Since a multiplier value "n" equal to fifteen was chosen, the current in the resonant tank reached an oscillation frequency of 7.5 MHz. The design methodology was validated by simulations in SPICE, complying with the established design parameters. [ABSTRACT FROM AUTHOR]

Nowadays the efficient use of energy is a major issue in applications such as electric vehicles. However, there are some phenomena that affect electric vehicle performance. One of those phenomena is the torque ripple of electric motors, which interferes with traction and the suspension system (causing vibration that stresses this system), and it can also introduce electric current harmonics into the battery, reducing its life, since torque ripple is partly a consequence of non-sinusoidal back EMF. For those reasons this is a topic worth investigating. The torque ripple of permanent magnets (PM) motors can be reduced in design or through control. Since control techniques have been reviewed and design methods have not, this paper presents a comparison of several design techniques to reduce torque ripple by different approaches and categorize them to show the characteristics of each group. A discussion is then made about the advantages and disadvantages of the designs, in general, as well as some comments about the missing, but important information, in the papers, such as the effects on efficiency. The study shows that a combination of methods provide the best results, although it complicates fabrication and suggests that this is a promising line of future investigation on torque ripple reduction methods. [ABSTRACT FROM AUTHOR]

This study presents a mathematical model of a parabolic trough solar collector with photovoltaic cells integrated into its solar receiver. A case study is presented, utilizing meteorological data obtained from the localities of Cuernavaca and Mexicali in Mexico. The results demonstrate moderately variable electrical and thermal energy production for Cuernavaca (387.93 kWh to 239.38 kWh and 1036.11 kWh to 641.26 kWh, respectively). In contrast, the production of electrical and thermal energy in Mexicali exhibited considerably greater fluctuations (515.16 kWh to 177.69 kWh and 1424.39 kWh to 448.88 kWh, respectively). Furthermore, a parametric study is presented, which analyzes the impact of solar receiver geometry and mass flow on the model's behavior. The results demonstrate that the pipe length exerts the most significant influence on the electrical and thermal power output (1.21 kW to 2.22 kW and 3.7 kW to 6.9 kW, respectively). Additionally, the diameter has an impact on the thermal power output (5.23 kW to 7.1 kW) and the electrical and thermal efficiency (0.18 to 0.15 and 0.54 to 0.74, respectively). Modifying the mass flow facilitates the enhancement of electrical power and efficiency (1.54 kW to 1.72 kW and 0.16 to 0.18, respectively) while concurrently preventing a significant reduction in thermal power and efficiency (5.4 kW to 5.3 kW and 0.56 to 0.55, respectively). A script with the developed model is provided. [ABSTRACT FROM AUTHOR]

The study of this article mainly focuses on the assessment and performance of current and voltage inverters in ozone generation, applying power density modulation (PDM) and typical operation. The topologies designed were a voltage-source full-bridge inverter (VSFBI), a current-source full-bridge inverter (CSFBI), and a CSFBI without considers the PDM. The inverters were analyzed and implemented considering an inductor–capacitor–capacitor (LCC) series–parallel resonant tank for the VSFBI and an LC parallel resonant tank for the CSFBI. The duty cycle impact (Dm) of the modulation signal was analyzed, and all inverters were compared. Based on the results, the decrease in Dm allows increasing the ozone generation because of avoiding the dissociation of the ozone molecules. The maximum concentration and efficacy presented by the VSFBI in ozone production were 620 gr/m3 and 0.155 gr/min. Also, the maximum electrical efficiency was 91%; it was presented by the CSFBI without PDM. [ABSTRACT FROM AUTHOR]

This paper presents an igniter circuit for high-intensity-discharge (HID) lamps based on an inverter and a resonant tank that has been adapted to stabilize inductively an HID lamp by means of applying low-frequency quasi-square waveforms to voltage and current in the lamp in order to reduce the presence of the acoustic resonances. With the proposed improvement, the igniter circuit performs three different functions: 1) the lamp ignition; 2) the arc stabilization; and 3) the acoustic resonances reduction. This proposal allows the use of fewer components, and less energy processing is minimized, so the resulting ballast is cheaper and more efficient than other ballast that avoids the acoustic resonances when they are working with square waveforms in the lamp voltage and current. The circuit was validated experimentally by using a 70 W conventional high-pressure sodium lamp, which is operated with a frequency of 2 kHz. The results were an electrical efficiency of 94%, a crest factor in the lamp current of 1.41, and it was not observed the presence of acoustic resonances. [ABSTRACT FROM AUTHOR]

This paper proposed the use of a ringer, a self-switched inductive storage system, for applications involving reluctance accelerators, a kind of electromagnetic launcher, and compatible with applications where portability is a requirement. There will be shown three different useful approximations for the analysis of the ringer, employed as a power source for a reluctance accelerator. First, it described the equations governing the que behavior of an ideal unloaded ringer, and then the equations for the ringer with an uncoupled inductive load, and ultimately a Lagrangian model for the ringer as an inductive power source for a reluctance accelerator, capable to make predictions about the currents through the circuits and the exit speed of the projectile for a given firing. The accuracy of the predictions made with the third approximation, the Lagrangian model, was tested experimentally. [ABSTRACT FROM AUTHOR]

Summary: In this paper, the analysis, design, and implementation of a power supply based on a multi‐stage‐shunt class E amplifier applied to ozone generation are presented. The proposed topology operates with pulsating waveforms and allows unidirectional energy flow from the power supply to the load with no energy return. Furthermore, due to the multi‐stage operation, it presents a lower stress in the switches compared with other similar topologies. To validate the proposed topology, a prototype was designed to feed a set of ozone generating cells in a power range of 0 to 500 W. This prototype provides an efficiency of 95% with an ozone production of 10.5 g/h and efficacy of 22.89 g/kWh. The proposed power supply is an alternative to feed any other type of dielectric barrier discharge load while keeping the efficiency of the power supply above 90%. The analysis, design, and implementation of a power supply based on a multi‐stage‐shunt class E amplifier applied to ozone generation are presented; due to the multi‐stage operation, it presents a lower stress in the switches compared with other similar topologies and higher efficiency. To validate the proposed topology, a prototype was designed to feed a set of ozone generating cells in a power range of 0 to 500 W. [ABSTRACT FROM AUTHOR]

The main contribution of this paper is the use of sensorless active diodes to generate the gate signals for a three-phase boost-rectifier with a self-powered control scheme. The sensorless operation is achieved making use of the gate control signals generated by the active diode schemes on each of the switching devices using a pulse width half-controlled boost rectifier modulation technique (PWM-HCBR). The proposed scheme synchronizes the gate control signals with a three phase voltage supply. Autonomous operation is obtained making use of the output DC bus to feed the control circuitry, the active diodes and the driver circuitry. The three-phase boost-rectifier is supplied by a three-phase permanent magnet electric generator powered by a solar concentrator dish with variable voltage and variable frequency conditions. Experimental results report an efficiency of up to 94.6% for 25 W and an input of 3.6 V peak per phase with 450. [ABSTRACT FROM AUTHOR]

Energy harvesting has become an interest area to research, due to the wide range of applications were could be employed. AC energy harvesting schemes present an important disadvantage with respect to DC harvesting schemes, they need to synchronize the operation of the power converter with the electric generator voltage waveform. In order to get this synchronization there are different schemes reported, each one has its advantages and disadvantages and in function of the application they are representative or not. In this paper a review of the different AC energy harvesting schemes with different techniques used to synchronize the power converter and the electric generator are shown, at the end of the review a simple scheme with reduced number of components and minimum computational cost is proposed. [ABSTRACT FROM AUTHOR]

The arrangement of the full-bridge, current-source inverter as a power supply for ozone generators providing high power factor (PF) and high electrical efficiency in a single stage is the main contribution of this paper. The corresponding design, simulation, and experimental results are presented. Also, the use of the current-fed, full-bridge resonant inverter for PF correction in ozone generation applications is discussed. The proposed power supply consists of an ac supply, a single rectifier bridge, an input inductor to the inverter, four switches, an LC parallel resonant tank, a resonant transformer, and a set of ozone generating cells. Experimental results with the proposed topology provided 96% for PF, 91% for electrical efficiency, and ozone production of 614 mgO3/min, satisfying the requirements of the standard 61000-3-2, class A. [ABSTRACT FROM AUTHOR]

This paper is aimed to report the consequences in the use of the well-known bootstrap technique in single-phase current-fed full-bridge resonant inverters (SPCFFBRIs) operating with and without reactive energy. Based on both simulations (using the PSPICE software) and experiments it is shown that this technique is not feasible for this type of inverters when the load is predominantly reactive. The bootstrap technique conveniently operates when the load is purely resistive or resonant. The unfeasibility in the use of the bootstrap technique with reactive or nonresonant loads comes from the fact that the load voltage is applied to the bootstrap capacitor and, consequently, to the gate of the floating MOSFET, producing an imminent damage both in the control circuit and in the floating MOSFET. Therefore, other alternatives for feeding the floated MOSFETs must be considered. [ABSTRACT FROM AUTHOR]

In this paper experimental results for a linear generator with different end-effect constraints to obtain a qualitative comparison for adjusting the linear generator geometry (windings length and stator length), are presented. The use of linear generators in energy harvesting systems is very common nowadays. One of the problems of this kind of electric generators is an induced voltage distorted due to end-effects. The end-effect is produced by the rotor speed change at the borders of the electric generator and impacts directly on the induced voltage waveform and in the energy flux to the load. However, is not included usually on the methodology design of linear generators. The proposal presented in this work allows obtaining a sinusoidal induced voltage waveform instead of a pulsing induce voltage waveform as has been reported in literature. [ABSTRACT FROM AUTHOR]

In this paper, the analysis and design methodology of a high-frequency self-oscillating (SO) electronic ballast with lamp current control are presented. SO electronic ballasts have two important drawbacks: First, the lamp current varies according to the ac input voltage, causing undesired effects in the lamp brightness, and second, the design method lacks precision at very high frequency operation (greater than 200 kHz) mainly due to the Cgs parasitic capacitance. The ballast is modeled by using the descriptive function method and the extended Nyquist criterion; the model of the ballast includes a control circuit and takes into account the high-frequency effect of the MOSFET parasitic capacitance Cgs. Finally, experimental results of a 38-W SO electronic ballast prototype with lamp current control for high-intensity discharge lamps are presented to validate the analysis and the proposed methodology. The switching frequency is selected at 2 MHz in order to avoid the acoustic resonance problem. [ABSTRACT FROM AUTHOR]

In this paper, the dimming and frequency effects on stability, current crest factor (CCF), and power factor (PF) of high-intensity discharge lamps fed with square waveforms are experimentally evaluated. For this evaluation, the lamp was stabilized using resistances. The resistances were varied in function of the impedance of the lamp. The effects of dimming and frequency variation were observed for two types of lamps of different nominal powers. The results indicate the ranges in which the lamp is stable and the frontier values in which the lamp becomes unstable. The CCF and PF remain close to unity, and no acoustic resonances were observed during the applied tests. [ABSTRACT FROM AUTHOR]

In the field of structural damage detection through vibration measurements, most existing methods demand extensive data collection, including vibration readings at multiple levels, strain data, temperature measurements, and numerous vibration modes. These requirements result in high costs and complex instrumentation processes. Additionally, many approaches fail to account for model uncertainties, leading to significant discrepancies between the actual structure and its numerical reference model, thus compromising the accuracy of damage identification. This study introduces an innovative computational method aimed at minimizing data requirements, reducing instrumentation costs, and functioning with fewer vibration modes. By utilizing information from a single vibration sensor and at least three vibration modes, the method avoids the need for higher-mode excitation, which typically demands specialized equipment. The approach also incorporates model uncertainties related to geometry and mass distribution, improving the accuracy of damage detection. The computational method was validated on a steel frame structure under various damage conditions, categorized as single or multiple damage. The results indicate up to 100% accuracy in locating damage and up to 80% accuracy in estimating its severity. These findings demonstrate the method's potential for detecting structural damage with limited data and at a significantly lower cost compared to conventional techniques. [ABSTRACT FROM AUTHOR]

This paper is a summary of the last ten years of work on the study of parabolic trough collectors (PTCs) and compound parabolic collectors (CPCs) coupled to photovoltaic and thermal solar receiver collectors (SCR-PVTs). While reviewing the state of the art, numerous review papers were found that focused on conventional solar receiver collector (SRC) technology for solar thermal generation. However, there is a lack of review papers summarizing SRC-PVT hybrid technology for solar electric/thermal generation, which would be beneficial for researchers interested in this area of research. This paper provides a review of SRC-PVT hybrid technologies. The theoretical foundations for analyzing and modeling PTC and CPC concentrators coupled to SRC-PVT are described, with an emphasis on modeling through thermal resistances and energy balances. Additionally, this section provides a concise overview of previous studies that have addressed the modeling of PTC and CPC collectors coupled to SCR-PVT, as well as experimental information useful for the validation of new mathematical models of SRC-PVT. [ABSTRACT FROM AUTHOR]

This paper presents the design of a maximum power point-tracking (MPPT) technique for DC–DC converters that are used in energy-harvesting systems based on thermoelectric generators. This technique is based on the analysis of the characteristics of the converter to measure the open-circuit voltage indirectly. The main contribution of this article is that the algorithm measures the voltage at the maximum power point without the need to disconnect the source of the circuit, as happens when the fractional open-circuit voltage (FOCV) technique is used. The algorithm is based on a predetermined initial duty cycle, which is applied to the circuit, and the input voltage and input current are read. With these values, the open-circuit voltage and short-circuit current are calculated with equations obtained from the circuit. Then, it calculates the duty cycle at the maximum power point and applies it to the circuit. If this duty cycle does not obtain the maximum power from the circuit, the algorithm starts a second stage based on fuzzy logic to calculate an increase or decrease in the duty cycle. The designed technique was evaluated using a topology based on a DC–DC flyback converter variant and was compared with the P&O technique and obtained better results. The designed technique provides between 3.9% and 5.6% more power to the load than the P&O technique in a 20 W system. [ABSTRACT FROM AUTHOR]

Capacitive technology for wireless power transmission has been shown to be a good option for charging the batteries of electric vehicles. It offers better coupling between the transmitter and the receiver than inductive power transmission. On the other hand, it has some disadvantages; for example, it is very sensitive to the distance between plates. Several ideas have recently been proposed to overcome this disadvantage. However, a proper analysis methodology is still lacking, as is a proper design procedure for the circuits used in capacitive transmission. In this paper, an analysis and design methodology is presented for applying the Z-tank resonant circuit to capacitive power transmission, and the theoretical design methodology is based on normalized equations with respect to the operating resonance frequency. The analysis methodology and design procedure result in a circuit where the resonance frequency remains constant despite changes in the distance between the capacitive plates. The simulation results validate the proposal; to ensure robust, realistic simulation results, parasitic elements were considered in all reactive components, and robust models were built for the switching elements, such as MOSFETs and diodes. The results show that the multi-resonant characteristic of the circuit achieves maximum energy transfer and high efficiency. [ABSTRACT FROM AUTHOR]

• Pedal energy a clean and sustainable alternative. • Energy harvesters allows the self-sourcing of an exercise bicycle. • The main elements of a pedaling energy harvester are identified. • Transmission and transformation of pedal energy to electrical energy are revised. • A sequence to design a pedaling energy harvester is proposed. Pedaling energy is a clean and sustainable energy source capable of supplying power to a variety of low power electronic devices. Furthermore, pedaling energy has proven to be a sustainable energy solution, in combination with other renewable energy sources for developing communities. However, currently, the use of this energy is still limited. The main contribution of this paper is to present a review of static pedaling technologies that use rotary transducers to convert pedaling energy into electrical energy, to identify current advances and design trends, comparing and classifying the elements that integrate the main stages of energy transmission and transformation, identifying areas of opportunity to improve their functionality, efficiency or other aspects of interest. The review includes information about the human capacity to deliver power in a pedaling mechanism such as the cadence-power ratio, cadence-torque, maximum power, and critical power. As a result of the review are reported geometric structure, transducer type, power converter, transmission ratio, power output, among other of the reviewed systems data. Moreover, a design sequence, which is considered appropriate, is proposed to optimize the pedaling energy harvesters of static mechanisms. Finally, the review results, trends, and challenges are discussed. [ABSTRACT FROM AUTHOR]

This paper presents the design of a fault detection circuit applied to a silicon carbide Mosfet (SiC-Mosfet). Fault detection is done by monitoring the behavior of the gate signal. The most important characteristic that has been reported in literature is quick detection since the evaluation is done while the SiC Mosfet is turning-on. With this method fast detection is allowed for short-circuit and open-circuit failure with small times for detection which prevents to spread the failure to the full system. To validate the fault detection circuit a boost converter with SiC-Mosfet was designed. Experimental results validate the reliability of the proposal. [ABSTRACT FROM AUTHOR]

In order to solve the trajectory tracking task in a wheeled mobile robot (WMR), a dynamic three-level controller is presented in this paper. The controller considers the mechanical structure, actuators, and power stage subsystems. Such a controller is designed as follows: At the high level is a dynamic control for the WMR (differential drive type). At the medium level is a PI current control for the actuators (DC motors). Lastly, at the low level is a differential flatness-based control for the power stage (DC/DC Buck power converters). The feasibility, robustness, and performance in closed-loop of the proposed controller are validated on a DDWMR prototype through Matlab-Simulink, the real-time interface ControlDesk, and a DS1104 board. The obtained results are experimentally assessed with a hierarchical tracking controller, recently reported in literature, that was also designed on the basis of the mechanical structure, actuators, and power stage subsystems. Although both controllers are robust when parametric disturbances are taken into account, the dynamic three-level tracking controller presented in this paper is better than the hierarchical tracking controller reported in literature. [ABSTRACT FROM AUTHOR]