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A new gate driver with metal oxide thin‐film transistors (MO‐TFTs) has been presented for micro‐light‐emitting diode (Micro‐LED) display. The proposed gate driver employing linearly decreasing sweep signal generated module could realize the line‐by‐line pulse width modulation (PWM) driving method, which is valuable for application in high‐resolution Micro‐LED display compared with the conventional driving method employing global sweep signal. A simple Micro‐LED pixel circuit including an inverter module driven by the analog PWM method is employed to demonstrate the feasibility of the proposed gate driver. A 10 × 10 green Micro‐LED display array has been fabricated with MO‐TFTs backplane technology. It is shown that a 10‐μs width pulse and linearly scanning sweep signal can be successfully output. Consequently, the pixel circuit array can be driven properly under analog line‐by‐line PWM driving method. [ABSTRACT FROM AUTHOR]

Summary: This paper compares four modulation strategies applied to five‐phase voltage source inverters (5PH‐VSI). The modulation strategies under investigation are sine wave pulse width modulation (S‐PWM), fifth‐harmonic injection PWM (FH‐PWM), space vector‐PWM using two large vectors (2V‐SVPWM), and space vector‐PWM using two medium and two large vectors (4V‐SVPWM). The study utilizes simulations to analyze the results based on four performance criteria: low‐order harmonics (LOH), maximum modulation index (MMI), common mode voltage (CMV), and total harmonic distortion (THD) under balanced and unbalanced load. To validate the simulation results for these criteria, an experimental test‐bench is employed, which includes a 5PH‐VSI feeding an R‐L load, and controlled by a low‐cost STM32F4‐DISCOVERY microcontroller board. Additionally, a mathematical approach is used to calculate the total thermal losses (TTL) then simulations are performed using Piecewise Linear Electrical Circuit Simulation (PLECS) software to assess the modulation schemes based on additional thermal performance criteria: conduction losses (CL), switching losses (SL), TTL, the efficiency, and the maximum permissible heat sink thermal resistance (MPHTR) at the steady‐state regime. The results indicate that the 4V‐SVPWM method demonstrates superior efficiency in terms of THD. Furthermore, it showcases the lowest TTL at high switching frequencies, allowing for the best efficiency and minimizing MPHRT, therefore providing the largest margin for the heat sink thermal resistance design. On the other hand, the 2V‐SVPWM offers the highest MMI, but this comes at the cost of high TTL and some LOHs appearing. In addition, it exhibits the highest CMV for unbalanced load. S‐PWM and FH‐PWM offer the advantage of simpler implementation. [ABSTRACT FROM AUTHOR]

Summary: This paper presents a novel three‐phase hybrid multilevel inverter (TPHMLI) designed for grid‐connected solar photovoltaic (SPV) systems. The TPHMLI combines series‐connected bridge topologies of half and full circuits to generate 11 stages of line load voltages, reducing the need for DC sources. It also introduces an improved pulse width modulation (PWM) approach, addressing computational challenges and high‐frequency triggering issues. Practical validation in a laboratory setting demonstrates the MLI's functionality and effectiveness. Furthermore, the advanced MLI topology successfully addresses design issues in grid‐integrated SPV structures, including power quality, efficiency, and reliability. It excels in managing reactive power and fault obstructive capabilities. Extensive simulations using MATLAB/Simulink confirm its superior performance, making it a promising solution for power conditioning units in grid‐connected solar PV systems. This research contributes to clean and sustainable energy conversion technologies, enhancing power quality and cost‐effectiveness, with significant potential for practical applications in the renewable energy sector. [ABSTRACT FROM AUTHOR]

Summary: This article describes a generalized single‐phase multiwinding step‐up transformer‐based multilevel converter with optimized device count. The proposed topology comprises of a single dc source, eight switches (four unidirectional and four bidirectional) and a single high‐frequency multiwinding transformer. Phase disposition pulse width modulation (PDPWM) is used for the level creation. The proposed converter is examined qualitatively and quantitatively using the total number of transformers, PWM control method, switch count, voltage stress, and the number of gate drivers, all of which are favorable. All elements of transformer selection, winding requirements, and comparative study have been thoroughly examined. A thorough Lagrange multiplier method has been applied to minimize the copper losses and optimize the multiwinding transformer (MWT) winding. The proposed converter simulations are performed using the MATLAB/SIMULINK environment. Further, the validation of the result is confirmed by a hardware setup of 0.9 kW. [ABSTRACT FROM AUTHOR]

This paper proposes a novel power-factor-correction system for the harmonic suppression of high-power equipment. It connects a PWM (pulse width modulation) rectifier and several uncontrolled diode rectifier units in parallel. The PWM rectifier is not connected to the load, and the power of the IGBT device is lower than that of the traditional PWM rectifier. The diode rectifier unit is connected in parallel without the loop current, which is convenient for expansion. The diode rectifier unit can still work when the IGBT fails, which enables high reliability. When compared to conventional APFs (active power filters), the proposed system only controls the grid current as a sinusoidal wave at the power frequency, without tracking harmonics, which makes the control simpler and the current THD (total harmonic distortion) lower. In this paper, the operating modes of the proposed parallel system are analyzed and the mathematical model of the circuit is derived. In addition, the corresponding control strategy is proposed and the parameters of the LCL are designed. Finally, simulations were carried out to demonstrate the superiority of the proposed parallel system when compared with the traditional APF, and a 60 kW experimental platform was built to demonstrate the feasibility of the proposed scheme. [ABSTRACT FROM AUTHOR]

Wireless power transfer (WPT) systems or simultaneous wireless information and power transfer (SWIPT) systems support multiple charging frequency standards and usually transmit two or more frequencies simultaneously. Multi-frequency sinusoidal pulse width modulation (MF-SPWM) technology can output multiple sine wave frequencies at the same time with only one inverter, which effectively reduces the system size and improves compatibility. However, MF-SPWM and dead-time make the MF-inverter highly nonlinearized, with significant effects on the desired frequencies and the total harmonic distortion (THD) of the multi-frequency output. In this paper, a double Fourier series-based method of harmonic analysis for the dual-frequency inverter (DF-inverter) is proposed, which can accurately calculate the magnitude of each of the harmonics in the output of the DF-inverter taking into account the influence of dead-time. The calculation methods of the minimum pulse width and voltage THD of the DF-inverter are provided. An analysis shows that when the dead-time is less than the minimum pulse width, its influence is negligible. Meanwhile, when the dead-time is slightly larger than the minimum pulse width, there is a trade-off between the desired frequency component and the THD. Experimental results are given and they are consistent with the analytical results of the proposed method, and the error is within 2%. [ABSTRACT FROM AUTHOR]

A new multi gain SC inverter topology with fewer switching components and lower voltage stress is presented in this paper. It comprises eight switches and two capacitors, which raise the output voltage by three times the supply voltage. The capacitors voltages are automatically balanced to ensure proper operation. The circuit constructional, operation, and parameter optimisation techniques are discussed in details. A simple logic-based multicarrier Level Shift Pulse Width Modulation (LS-PWM) is employed to control the switching operation that reduces the complexity of the control circuit. Furthermore, a comparative analysis with other recent topologies has been presented to demonstrate the virtues of this approach. Finally, the proposed topology (PT) verification, feasibility, and effectiveness have been demonstrated both in simulation and experimentation. [ABSTRACT FROM AUTHOR]

Practical testing of distance relays under power swing conditions is becoming all the more essential. This is in view of the increasing use of power electronic apparatus due to penetration of renewable sources and/or FACTS controllers now-a-days. To perform such practical tests, a hardware platform emulating power system swing occurrences, as caused by electromechanical oscillation of alternators, is necessary. As a first step it is required to model the phenomenon before its implementation. In this paper an analytical small-signal model of the low-frequency electromechanical oscillations in a grid-connected alternator is presented. Off-line simulation-based validation for a Single Machine Infinite Bus (SMIB) system is done. To emulate an open-loop alternator, a prototype of a controlled grid synchronised VSI with AC-side reactor is developed and practically tested. A control scheme is proposed and implemented to emulate the active power swing phenomenon. Effects of machine inertia and initial power angle on the swing characteristics are investigated. In-process estimation of apparent impedances, as seen from the distance relay terminals downstream towards the grid, is done. Principle of estimating the apparent impedance during power swing is presented with corresponding experimental results. Both real-time and off-line simulation results are in close agreement with the experimental results thus establishing the accuracy of the model and the precision of the experiments. [ABSTRACT FROM AUTHOR]

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Introduction. In the contemporary world, alternative electrical energy has become an integral part of our daily existence, with the majority of our electrical materials, electronic devices, and industrial equipment relying on this energy source. Consequently, ensuring the quality of the electrical signal obtained is of paramount importance in the process of converting and distributing electrical energy. The improvement of the output voltage inverter can be achieved through adjustments to the inverter structure or by refining the control strategy. The novelty of the presented research lies in an innovative approach that employs real-time modulation for efficient control over the reduction of harmonics, alongside managing the fundamental component. This approach is applicable to both bipolar and unipolar configurations, featuring quarter-wave and half-wave symmetries. Purpose. Employing this modulation strategy aims to enhance the durability of the switching components and enhance the voltage output of the inverter. Methods. The methodology is founded on a sine-sine modulation as its foundational model. It constitutes an inventive pulse width modulation technique in which a reference sinusoidal waveform, operating at the desired signal frequency, is compared to a modified carrier signal with an identical time period as the reference signal. Results. This paper introduces a broader and more comprehensive approach, alongside specific solutions, for the control and mitigation of harmonics in three phase voltage source inverters. The proposed method offers precise control over the reduction of harmonics and the fundamental component, and it can be implemented in extensive power electronic converters. Practical value. To assess the effectiveness of the given control approach, we conducted simulations as well as real-time implementation employing Dspace DS1104 controller board. The outcomes were highly favorable, confirming the effectiveness and validity of the suggested control algorithm. References 15, tables 4, figures 7. [ABSTRACT FROM AUTHOR]

Introduction. Multilevel inverters (MLIs) are a popular industrial and, more especially, renewable energy application solution. This is because of its appetite for filters, low distortion class, and capacity to provide a multilayer output voltage that resembles a pure sine waveform. The novelty is in applying the wild horse optimization algorithm (WHOA) to adjust the sinusoidal pulse width modulation (SPWM) technique by producing the optimal reference signal parameters in a new multilevel inverter architecture known as the packed U-cell multilevel inverter (PUC-MLI). Purpose. This study helps with the idea of new inverter architecture and a modified pulse width modulation (MPWM) method to make the multilevel inverter smaller, cheaper, and with less total harmonic distortion (THD). Methods. We use the proposed approach to control a 7-level, single-phase PUC-MLI. The WHOA is used to discover the optimal parameters of the additional reference sine signal after being compared with SPWM to evaluate its performance in harmonic reduction. The simulation’s outcome was validated by building a PUC-MLI prototype. Results. Experimental results and simulations validate the effectiveness of the suggested approach. The WHOA-improved MPWM approach achieves a significant reduction in THD on the PUCMLI output voltage, as indicated by the results. Practical value. THD in MLI output voltage will be reduced without spending any cost. The suggested solution works with many MLI topologies with varying output voltage levels. References 20, tables 6, figures 12. [ABSTRACT FROM AUTHOR]

Owing to the effect of temperature on the maximum power point of photovoltaic modules, the anticipated benefits of maximum power point tracking charge controller are also greatly affected under high-temperature environments. This paper presents experimental study results based on the investigations of the effect of high cell temperatues on the performance of maximum power point tracking charge controllers. The study was carried out over three months at Kenyatta University in Nairobi, Kenya under moderate and high temperature conditions. The experiments are carried out using two market-ready maximum power point tracking charge controllers and a normal pulse-width modulation charge controller as the reference. The study establishes that below 50 °C, the maximum power point tracking charge controller exhibits significant advantages over its counterpart with about 24% - 29%, additional energy gain. However, at high cell temperatures, the maximum power point tracking charge controller loses its added advantage over the pulse-width modulation charge controller and its performance benefits drop from an average of 28% to 0.2%. This demonstrates that an ordinary pulse-width modulation charge controller would achieve the same yields under high-temperature conditions and at an even lower premium. [ABSTRACT FROM AUTHOR]

This paper deals with Distributed Generation (DG) system requiring power quality features such as current harmonics, reactive power compensation, and power factor improvement in grid tied operation. The motivation is to combine DG system with the capabilities of shunt active filter to perform real power injection, current harmonics mitigation and power factor improvement. The control algorithm employed in this setup utilizes a reference current generator based on p-q theory together with a pulse width modulation controller for switching pulse generation. The control strategy utilizes PI controller with Genetic Algorithm (GA) and Particle Swarm Optimization (PSO) for finding optimal PI controller parameters. The effectiveness of the proposed method is verified using MATLAB/Simulink and experimental model developed for 3kWp inverter. The PI-PSO controller injects 0.588kW active power into the grid results in sharing 54% of load power demand and the current harmonics is reduced from 23.70% to 1.63%. The obtained results demonstrate that the grid tied inverter maintains harmonic standards in accordance with the IEEE-519 standard while injecting maximum possible active power to the line. [ABSTRACT FROM AUTHOR]

This brief proposes an improved pulse width modulation (PWM) scheme, which uses diode voltage clamping characteristics to achieve the direct control of three‐phase current source converter without any logical transformation. Compared with the traditional indirect carrier modulation scheme—mapping‐PWM, the proposed scheme can solve the disadvantages of low DC current utilization, high switching loss, and complex control process. The generation mechanism of IPWM is analyzed in this brief. Then, based on the generation mechanism, the output characteristics of the system under IPWM are analyzed and compared with the traditional modulation scheme. Finally, the experimental results verify the effectiveness the proposed modulation scheme. [ABSTRACT FROM AUTHOR]

The three-level (3-L) neutral-point-clamped (NPC) converter has found widespread applications in various fields, due to its simple structure, low failure rate and high efficiency. However, the 3-L NPC converter suffers the issue of unbalanced neutral-point (NP) voltage due to the divided two dc-side capacitors. The large NP voltage ripple and offset Based on the detailed analysis of the effects of vectors and clamping patterns on the NP voltage, a discontinuous optimized modulation method for NPC grid-connected inverter with both low switching loss and ability to balance NP voltage is presented. By measuring NP voltage and utilizing the property that superfluous clamping patterns have opposing effects on the NP voltage, the modulation method adjusts the NP voltage with the injection of various zero sequence voltages (ZSV) into the original sinusoidal waves. The results of this study demonstrate that the CB-DPWM can control the NP voltage balanced and decrease switching loss compared to conventional DPWM and SVPWM strategies. Moreover, the CB-DPWM strategy does not need to identify sectors and subsectors or calculate dwelling times. This modulation strategy effectively suppresses low-frequency fluctuations and deviations of the NP voltage with the injection of a simple ZSV, and improves the power quality of the output voltages and currents. Compared to the traditional SVPWM scheme, the suggested CB-DPWM has a 27 % lower overall IGBT loss. Moreover, this method is implemented through carrier waves, which is simpler than modulation schemes based on space vector, greatly shortens the program running time, and is conducive to engineering implementation. [ABSTRACT FROM AUTHOR]

The six‐switch inverter has gained significant attention due to its ability to achieve dual AC voltage outputs with fewer semiconductor power devices. However, with existing pulse width modulation (PWM) algorithms, the switching frequency of the two middle‐position power devices is twice that of the other four power devices at the upper and lower ends. Therefore, this paper proposes an improved PWM algorithm for the six‐switch converter based on the unipolar modulation principle. The proposed algorithm can significantly reduce the switching frequency of the two middle‐position power devices. Research results indicate that, under optimal conditions, the switching frequency of the two middle‐position power devices is as low as the frequency of the AC output voltages, and in the worst‐case scenario, it is only half the carrier frequency. Consequently, the efficiency of the inverter is effectively improved. Additionally, analysis results suggest that, given the same switching frequencies of power devices, the modulation algorithm proposed in this paper for controlling the converter also results in lower Total Harmonic Distortion (THD) for the output voltages compared to traditional modulation algorithms. [ABSTRACT FROM AUTHOR]

The paper deals with the dynamics of a resistance spot welding system. At the core of this system is a transformer, which is powered on the primary side by a pulse-width modulated inverter and has a full-wave output rectifier on the secondary side that provides a direct welding current. The entire system is nonlinear, due to magnetic hysteresis and electronics. The electronics prevent the current from flowing in all parts of the welding transformer at separate time intervals during the voltage supply period; therefore, not all the parameters affect the dynamic of currents and voltages all the time so the system is also time-variant. To design a high-performance welding system and to predict the maximum possible welding current at a specific load, it is necessary to know the welding and primary currents. The leakage inductances of the system can reduce the maximum welding current significantly at higher frequencies and the same load. There are several methods to determine these currents, each with its drawbacks. Measurements are time-consuming, using professional software is expensive and requires time to learn and free open-source software has many limitations and does not guarantee the correctness of the results. The article presents a new, fourth option—a theoretical derivation of analytical expressions that facilitate straightforward and rapid calculation of the welding and primary currents of the resistance spot welding system with symmetrical secondary branches. The derivation of the mathematical expressions is based on the equivalent circuits that describe the system in different operating states. The results of the numerical simulations confirmed the derived expressions completely. [ABSTRACT FROM AUTHOR]

The three‐level Vienna rectifier is widely used in industrial applications, such as electric vehicle charging systems and telecommunication power systems. Discontinuous pulse width modulation (DPWM) is widely used in three‐level AC/DC converters due to its features of switching loss minimization. However, the problems of neutral‐point voltage ripple, current zero‐crossing distortion, and switching losses are mutually coupled for the Vienna rectifier. To address these issues, a hybrid carrier‐based discontinuous pulse width modulation (HCB‐DPWM) with reduced neutral‐point (NP) voltage ripple and current distortion is proposed. First, the π$$ \pi $$/6 clamping period of the conventional DPWM is divided into three‐type clamping intervals, which reduce NP voltage ripple with shortened clamping period. Then, the elimination of current distortion around the current zero‐crossing point and the switching loss reduction are investigated. The implementation of the proposed HCB‐DPWM is given in detail. Finally, the simulation and experimental results of the Vienna rectifier are presented to validate the performance that the proposed HCB‐DPWM can eliminate current zero‐crossing distortion and reduce neutral‐point voltage ripple with different modulation indices. [ABSTRACT FROM AUTHOR]

Soft switching reduces voltage and current stress during transitions, smoothing and quieting operations and reducing electromagnetic interference while also increasing efficiency and equipment lifespan. Circuit design, component selection, and switching frequency optimization affect power electronics soft switching. This paper proposes boost integrated half-bridge dual-output series resonant (BIHBDOSR) converter, a novel converter design and control method to increase series resonant converter performance by reducing storage element size, switch count, and switching losses. This methodology relies on soft-switching technologies like zero-voltage switching (ZVS) and zero-current switching (ZCS). These methods use class-D, class-E, series, parallel, and series–parallel resonant converter circuits to increase efficiency and minimize component stress. The proposed converter is ideal for constant voltage, constant power, and current-controlled loads with the output voltage being regulated by a closed-loop PI controller. The output voltages for two loads in the simulation depart from reference values. V01 changes from 14 to 20 V and V02 from 18 to 15 V at 300 ms owing to switching variances. The proposed converter utilizes gate driver circuits, resonant tank circuit, current sensor, FPGA board for closed-loop control, and current sensor for stability, ensuring converter stability. The proposed converter closed-loop control method modifies PWM signals to regulate both loads independently and ensure steady output voltage. Additionally, to validate the effectiveness of proposed converter, a 50-W driver circuit is designed, delivering two independent outputs of 20 W and 30 W. Frequency modulation (FM) and duty cycle control methods are employed to obtain the desired outputs. [ABSTRACT FROM AUTHOR]

In the inverter circuit, the speed at which the MOSFET is impacted by the presence of a parasitic inductor within the printed circuit board (PCB) leads to a delay in the switching process. Furthermore, the parasitic inductor within the circuit can easily form an LC oscillation with the parasitic capacitor of the MOSFET. These two issues result in an inconsistency between the actual output of the MOSFET and the driving signal waveform, leading to distortion in the sinusoidal pulse width modulation (SPWM) waveform and an increase in total harmonic distortion (THD). It is a common practice to mitigate gate oscillation by introducing a resistor at the gate of the MOSFET. However, elevating the resistance leads to deceleration in the charging process of the MOSFET's parasitic capacitor, consequently causing an increase in the switching delay, and thereby increasing THD. Therefore, an effective strategy to reduce THD is proposed in this paper, while augmenting the gate resistance, computing the MOSFET switching delay, and applying corrective compensation. In this way, the inherent issues of the switch are addressed, resulting in inverter output waveforms that closely resemble sine waves and reduced THD. Through a combination of simulation and empirical experimentation, the efficacy of the proposed approach in significantly reducing THD in the inverter's output waveform has been empirically substantiated. [ABSTRACT FROM AUTHOR]

Traditional biomass boiler operations predominantly rely on manual control, with adjustments made based on operator experience. This approach not only demands considerable manpower but also leads to suboptimal resource utilization. Addressing the specific operational dynamics of biomass boilers, this study introduces a controller designed around the STM32 microcontroller. This device employs a modular architecture and incorporates cost-effective chips and peripheral components. To enhance energy efficiency and the overall user experience, the controller utilizes pulse width modulation pulse modulation alongside a fuzzy PID control strategy. Capable of toggling between manual and automatic modes for local operations, it also supports data logging directly on the device or in the cloud. Tailored to meet diverse user requirements, the controller facilitates remote monitoring and management. It employs a strategic control mechanism for various motors, ensuring precise hot water temperature measurements within the boiler and enabling data uploads to cloud platforms. This not only conserves energy and reduces labor costs but also promotes environmental sustainability and operational efficiency. Through ongoing refinement and rigorous testing, the controller has achieved a level of maturity that underscores its readiness for widespread implementation. [ABSTRACT FROM AUTHOR]

Power losses in semiconductor devices present a significant impediment to advancing power electronics systems for achieving higher frequencies, improved efficiency, and greater integration. A major challenge lies in directly coupling power losses with various control strategies, considering the variations in manufacturers, packaging, and process structures within the power electronics field. This paper introduces a field‐circuit coupling simulation methodology of the insulated gate bipolar transistor (IGBT) within the Simulink/COMSOL environment, using a conventional three‐phase six‐switch voltage source inverter (VSI) IGBT module as a case study. A composite transfer function interconnects the electrical and thermal aspects, enabling bidirectional coupling between IGBT temperature and losses. This study aims to comprehensively compare the effects of various control strategies, namely, single‐vector, dual‐vector, and three‐vector current model predictive control (CMPC) and space vector pulse width modulation (SVPWM), on the losses and temperature of IGBT power modules. The findings emphasize that losses are significantly influenced by the selection of weighting factor coefficients and power factor settings under the same CMPC control strategy with a fixed switching frequency. Additionally, the selection of control strategies, such as CMPC and SVPWM, substantially impacts power losses in power electronic devices. [ABSTRACT FROM AUTHOR]

Simulation and implementation of a single DC-link-based three-phase inverter are investigated in this article. The primary focus is on designing a single DC-link three-phase inverter for high power applications. Unlike conventional inverters that require 600 V to generate 400 V (RMS) at the output, the proposed system achieves this with only 330 V, facilitated by a 12-terminal 1:1 transformer. The system employs Proportional Integral (PI) and Neural Network (NN) controllers to optimize performance. Various Carrier-Based Pulse Width Modulation (CB-PWM) techniques, including Phase Disposition (PD), Phase Opposition Disposition (POD), and Alternative Phase Opposition Disposition (APOD), are implemented and evaluated based on Total Harmonics Distortion (THD) concerning the Modulation Index (MI) of the inverter. The proposed inverter achieves a THD reduction to 4.8%, demonstrating superior performance compared to recent studies. The system's performance is validated through extensive MATLAB/Simulink simulations and practical implementation using XILINX FPGA software, confirming the efficacy of the proposed design. [ABSTRACT FROM AUTHOR]

Amongst the various topologies of multi-input multi-output (MIMO) DC-DC converters, single-inductor MIMO (SI-MIMO) converters have the advantages of a reduced component count, a simpler structure, and low cost. These converters are suitable in electric vehicle (EV) applications involving variable ports, essential for performing different functions. Digital control in SI-MIMO converters is promising for enhancing transient performance due to its numerous benefits. However, delays in digital control, particularly computational and pulse width modulation (PWM) delays, can negatively impact the performance of DC-DC converters. Multi-sampling and double PWM update methods can mitigate these control delays, but they often necessitate complex control schemes, adding computational burden. In this work, an advanced multi-sampling PWM technique, integrating sample shift and multi-sampling, is proposed while employing a simple digital PID control scheme. The proposed method was tested for a shared-switch SI-MIMO converter with battery discharging and charging modes in the MATLAB/Simulink environment and compared with the conventional single- and multi-sampling PWM methods. The results demonstrated that the proposed method significantly improved the converter performance, surpassing the conventional single- and multi-sampling PWM methods. In the battery discharging mode, utilizing the proposed method, the output voltage achieved a settling time of 0.075 s in response to a step change in its reference, significantly outperforming multi-sampling, which yielded a settling time of 0.124 s, and single sampling, which exhibited an even longer settling time of 0.898 s. It also demonstrated a minimal overshoot of 0.06 volts compared to 1.5 volts with multi-sampling during the step change in the input voltage. Similarly, in the battery charging mode, upon a step change in the reference output voltage, the proposed method effectively minimized the overshoot of the output voltage to 0.845 volts compared to 1.175 volts with multi-sampling, and it decreased the inductor current settling time to 0.296 s from 0.330 s recorded under multi-sampling. These findings underscore the potential of the proposed method in enhancing the digital control performance of SI-MIMO DC-DC converters in electric vehicles. [ABSTRACT FROM AUTHOR]

The authors present the multi‐physical field performances comparative research for a 30 kW, 30,000 r/min high‐speed permanent magnet motor (HSPMM) when the motor is powered by the sinusoidal pulse width modulation (SPWM) voltage inverter and sinusoidal voltage source, respectively. Firstly, electromagnetic performances including torque, voltage and current of the HSPMM with different driving methods are compared and analysed by the finite element method (FEM). Considering the effects of high operation frequency, power losses of the HSPMM with different driving methods under full‐load conditions are calculated and compared with the skin effect and the proximity effect considered for HSPMM winding copper loss estimation. Based on the above analysis, a prototype driven by the SPWM voltage inverter is manufactured, with its electromagnetic and thermal performances tested and verified. In addition, several influencing factors of the HSPMM rotor eddy current loss are studied, with their effects on the HSPMM under different driving methods further analysed and compared as well. A novel equivalent power supply method is proposed to effectively save the calculation time with a negligible error. Finally, in order to further improve the heat dissipation capacity of the HSPMM, a novel cooling method is intensively studied with its influencing factors further analysed. The cooling effect of the novel cooling method and the temperature of the motor components are verified and calculated by the computational fluid dynamics (CFD) method. [ABSTRACT FROM AUTHOR]

This paper presents a highly efficient dual-mode HV (high voltage) buck converter which operates at both light and heavy load currents. To improve the conversion efficiency at two different load conditions, a dual-mode design composed of pulse width modulation (PWM) and pulse frequency modulation (PFM) were implemented using TSMC 0.5- $\mu $ μ m HV CMOS process. The chip area is 2038.05 $ \times $ × 1689.85 $\mu $ μ m2, while the input voltage ranges from 12 V to 15 V. A 92.95% peak efficiency at a load current of 10 mA was achieved based on on-silicon measurement results. [ABSTRACT FROM AUTHOR]

For making the grid to be more intelligent, a unique design is required in this changing sphere. A better-automated grid is more important for controlling the variations in the entire system. This is possible by introducing secondary controllers where both power and voltage are shifted at necessary stages. Therefore, in this article, a Neural Fizzy Identification System with Partial Integral Controller (NFISPID) is introduced. Also, a secondary controller named Selective Voltage Pulse Width Modulation with Hybrid Artificial Bee Colony-Particle Swarm Optimization technique is incorporated for handling all false situations in the grid. The efficiency of the proposed system is checked with MATLAB environment where the results prove to be much efficient in terms of all parametric values, and the grid becomes stable within a short span of time than other existing controllers. [ABSTRACT FROM AUTHOR]

Summary: In this study, couple inductor‐based buck power factor correction (PFC) converter is designed to mitigate dead zones of the converter. To minimize switching losses, all switches are controlled using a soft switching method, eliminating the need for snubber circuits. The circuit is controlled by an analog UC3843 pulse width modulation (PWM) integrated circuit (IC), providing natural PFC capability, which simplifies control and offers advantages in terms of size and cost compared to conventional ones. Simulation studies and prototype implementation are carried out to evaluate performance of the topology. The converter operates within a voltage range of 90–280 Vrms and has a power rating of 150 W. The results from both simulation and experimental analyses indicate that power factor (PF) of the circuit exceeds 98% and total harmonic distortion (THD) of the input current is found to be below 5% under various input voltage and load conditions. Furthermore, proposed topology demonstrated high efficiency, with measurements of 93% at full load and 95.6% at half load under 220 Vrms input voltage and 80 Vdc output voltage conditions. Outcomes highlight that the proposed topology achieves pure sinusoidal input current and exhibits competitive performance compared to other topologies used in the industry. [ABSTRACT FROM AUTHOR]

Summary: A single‐source switched capacitor multilevel inverter (SCMLI) topology utilizing only 10 switches and 1 diode with the capability of generating seven output voltage levels and a triple voltage boosting factor is proposed in this paper. The converter has capacitors that are self‐balanced and do not require any additional circuitry. The multicarrier sinusoidal pulse width modulation (PWM) technique is used to generate various switching signals for the 10 switches. Moreover, the reliability analysis using the Markov model has been carried out to assess the lifespan of power electronic components used in the proposed converter. The converter's performance is analyzed when an open circuit fault occurs in one or multiple switches. Power loss and efficiency in the converter are calculated by PLECS software using thermal modeling. The efficiency of SCMLI was found to be 97.6% for a 300 W load. The inverter working is verified by building a 500 W prototype in the lab. The experimental results in steady‐state and dynamic conditions agree with the theoretical and simulation analysis. [ABSTRACT FROM AUTHOR]

Summary: Frequency‐domain detection stands as a critical method in remote geophysical exploration; however, its practical application is constrained by the considerable size of the requisite instrumentation. In this paper, we present a compact frequency domain electromagnetic detection system. The integration of intelligent power devices and a novel hardware architecture substantially diminishes the system's dimensions, thereby enhancing its portability. Furthermore, the system design incorporates sinusoidal pulse width modulation and digital phase‐locked amplification to ensure the efficacy of the proposed system. Both the transmitter and receiver system are constrained to dimensions smaller than 1.5 m. Subsequent experimental validation attests to the exemplary hardware performance of the proposed system, with the transmitting voltage of the transmitter circuit attaining 500 V, and the receiver circuit exhibiting a sensitivity as low as 10−8 V. Significantly, this design paradigm not only facilitates the integration of transmitter and receiver systems for frequency‐domain electromagnetic detection but also introduces novel prospects for the application of frequency‐domain electromagnetic detection methods across diverse fields. [ABSTRACT FROM AUTHOR]

This paper introduces a novel multi-output converter featuring a partial-feeding power factor correction (PFC) inductor circuit. The proposed circuit comprises a multi-winding PFC inductor and a voltage doubler rectifier. One of the outputs (output1) is regulated by the pulse frequency modulation of the LLC resonant converter which applies the ordinary control method. While the other output (output2) is controlled by the pulse width modulation of the buck converter, which is connected to the partial-feeding PFC inductor circuit. The buck converter, which is structured as a stacked combination of output2 and the buck converter's output, efficiently manages a small power fraction to regulate output2. Despite accommodating universal input voltage, the partial-feeding PFC inductor circuit restricts the fluctuation of the input voltage range for the buck converter due to the presence of a voltage doubler rectifier. Moreover, the adoption of the partial-feeding inductor circuit in the PFC replaces one of the DC–DC converters and leads to a reduction in the power stage. As a result, the proposed multi-output converter achieves a tight regulation of multiple outputs, thus ensuring high efficiency and power density. [ABSTRACT FROM AUTHOR]

This paper presents the design of a 35 kW isolated fuel-cell DC–DC converter (FDC) with a hybrid switch structure. By utilizing a circuit structure and pulse-width modulation (PWM) method that enables the use of insulated-gate bipolar transistors (IGBTs), the price is reduced without a significant efficiency degradation even at frequencies of tens of kHz when compared to using all silicon carbide metal–oxide–semiconductor field-effect transistors (SiC-MOSFETs). The proposed converter is based on a PWM resonant converter, which has good switching characteristics and low-voltage stresses on the switching devices. However, it suffers from high cost owing to heavy current stresses. This problem can be solved using a hybrid switch structure that adopts IGBTs in the leading-leg switches. Considering the wide variations in the input and output voltages, the design of the main parameters, the selection of power semiconductors considering the switching characteristics, and the frequency selection method are presented. The feasibility of the proposed FDC design is verified using a prototype implemented with an output power of 35 kW (input voltage = 330–610 V and output voltage = 450–850 V) and a switching frequency of 40 kHz. [ABSTRACT FROM AUTHOR]

Three-level DC–DC converters (TLDCs) have attracted industrial and academic attention because of low main switching voltage ratings, simple clamping structure, and good soft-switching characteristics. This paper proposes a new TLDC with combined operation modes, which can operate in both zero-voltage switching (ZVS) and zero-voltage zero-current switching (ZVZCS) modes. The proposes converter varies soft switching mode with a simple switching combination of Sr1 and Sr2, and follows the best efficiency curves over a wide load range. Compared to conventional ZVS or ZVZCS TLDCs, this solution minimizes the circulating current and increases the overall efficiency. In addition, the current stress of the flying capacitor is also low. And, all these good features are realized by two low VA rating MOSFETs. This paper discusses the circuit, operating principles, and some steady-state characteristics. Finally, experimental data from a 1 kW prototype demonstrates the validity and characteristics of the proposed converter. [ABSTRACT FROM AUTHOR]

A zero current transition (ZCT) pulse-width modulation (PWM) DC–DC boost converter operating in boundary conduction mode (BCM) is proposed in this paper. The auxiliary circuit of the proposed converter ensures the main switch to turn off with ZCT. Also, due to the operation of the proposed converter in BCM, naturally zero current switching (ZCS) is achieved for the turning on process of the main switch and the turning off process of the main diode. The proposed converter does not contain additional voltage and current stresses across the main components. The operation modes and theoretical analysis of the proposed ZCT PWM DC–DC boost converter operating in BCM are shown in detail. Detailed ZCT cell analysis and selection procedure of the resonant components which ensure the ZCT operation of the main switch are realized. The proposed converter is designed and tested, and experimental results are obtained in the laboratory. The total losses of the proposed converter are decreased by 53.77%, and its efficiency is increased by 3.2% compared to hard switching (HS) converter at 462 W nominal output power. [ABSTRACT FROM AUTHOR]

This work has proposed a minimum switch single-phase nine-level inverter with a new modified carrier pulse width modulation approach. The proposed arrangement delivers a high amount of resultant voltage levels by using a lesser amount of switching devices and ternary sequence DC sources. Furthermore, to improve the quality of resultant voltage and enhance the harmonic spectrum, a newly modified carrier pulse width modulation (PWM) approach is suggested. The suggested design can easily be extended by using a series connection. To prove the better effectiveness of the proposed inverter configuration, a comprehensive comparison with the other nine-level configurations in terms of the required number of sources, switches, capacitors, diodes and conducting switches is performed. The effectiveness and feasibility of the new multilevel inverter structure using the proposed PWM approach have been proven by using MATLAB simulation and prototype results. [ABSTRACT FROM AUTHOR]

A major challenge with the integration of renewable energy sources (RES) into microgrids is their inherent variability and intermittency, affecting the power supply's reliability and quality. Photovoltaic (PV) and wind power conversion systems (WECS) are two examples of RES. The hybrid optimization and control techniques addressed in this work contribute to stable, reliable and efficient microgrid operation, which is essential for the successful integration of RES and the overall resilience of energy systems. Enhancing a PV system's performance within a hybrid energy microgrid is the main goal of this effort. Microgrid components consist of a PV system, a doubly fed induction generator (DFIG)-based WECS and a supercapacitor because power generated from PV and WECS sources is intermittent. To effectively manage the PV system's output, a control strategy is employed using an improved Landsman converter and a hybrid whale artificial bee colony optimization (WABCO)-based proportional–integral (PI) controller. Pulse width modulation (PWM) rectifier coupled to the WECS produces a DC output that is stabilized with the help of the PI controller. A synchronous PI current controller approach is also utilized to synchronize grid voltage. The proposed control methodology is validated through comprehensive simulations conducted in MATLAB, demonstrating the dependable and consistent operation of the designed microgrid. [ABSTRACT FROM AUTHOR]

The permanent magnet synchronous motor (PMSM) avoids commutation-related torque ripples and produces smooth torque. Its great handling capacity and better efficiency make it an excellent choice for high-demand applications. A typical PM motor drive fed with pulse width-modulated voltages may cause the motor insulation to break down if rapid voltages (dv/dt) occur across the motor terminals. Applying variable voltage with low dv/dt and implementing multiple inverter topology can solve this issue. Multilevel converters have minimal switching losses, better power quality and the ability to operate at both fundamental and higher switching frequencies. In this study, a three phase stacked multilevel inverter-based FOC driven PMSM drive design is proposed. Here, the neutral point is a capacitor intermediate point on DC side, where current is naturally balanced throughout a switching cycle. This makes it possible to use downstream batteries and even lower voltage equipment, greatly increasing efficiency, improved performance and smother control at low speed. Therefore, direct-battery-driven electric vehicles will be able to use this. A 33 level inverter-based PMSM drive was used to implement the FOC, and the simulation results were used to validate it. The Matlab/Simulink tool is used to simulate the entire system. [ABSTRACT FROM AUTHOR]

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Based on the design concept of dynamic and static isolation, disturbance-free payload (DFP) satellites can isolate the effects of interference on sensitive payloads, and can realize the high-precision control of the payload better than a traditional spacecraft. Among these, non-contact annular electromagnetic stabilized spacecraft (NCAESS) can effectively alleviate control output problems such as the six-degree-of-freedom coupling and nonlinear effects found in traditional non-contact spacecraft. As a key actuator, the driving current control of the non-contact annular electromagnetic actuator (NCAEA) will have a direct impact on the attitude performance of NCAESS. However, there are multiple interference effects present in the actual driving current control. Therefore, this paper proposes a composite control scheme to improve the driving accuracy by suppressing these multiple disturbances. Firstly, the variable-switching-frequency pulse-width modulation is used to adjust the switching frequency adaptively to reduce switch ripple. Secondly, feedforward compensation is employed to mitigate the back electromotive force. Thirdly, the robust Smith predictor is utilized to compensate for the digital control delay. Finally, an internal model proportional–integral controller with fuzzy rule is applied to adjust the parameters adaptively. The numerical simulation results demonstrate that the proposed approach can be adopted to enhance the robustness and dynamic response of the driving current effectively, which leads to precise control of the non-contact annular electromagnetic stabilized spacecraft. [ABSTRACT FROM AUTHOR]

The multilevel inverter (MLI) is a power electronic circuit applied for power and voltage applications. It has the advantages of minimum total harmonic distortion (THD), less voltage stress on the switching devices, fewer switching losses, and a smaller size of passive filters. These high-level inverters are applied in applications like AC drives, FACTS, and in the field of renewable energy. There are various inverters for such applications. A PUC multilevel inverter contains fewer components, fewer switching losses, and easy-to-balance voltage on capacitor sides. In this paper, the performance of the transformer less seven-level inverter and the five-level inverter is analyzed. The sinusoidal pulse width modulation (PWM) has been used with this PUC-based structure. The new control strategy is designed to reduce harmonic contents and low filter ratings. A relative analysis is carried out to focus on the superiority of the recently developed packed U-cell topology. The performance of packed U-cell, seven-level, and five-level inverters has been compared. These types of inverters consist of two power switches and a single capacitor to make this inverter effective. The PUC 7 inverter contains a lot of sensors and other control components to balance the voltage on the capacitor side by one-third of the input voltage, so the structure becomes complex. While PUC 5 is sensor less technology, there is no voltage balancing issue and no complexity found in this inverter. In PUC5, the only level is low, but it is very easy to interface with grids and other devices. So it is the most preferable as compared to PUC7. The performance analyses of these inverters have been verified through simulation. [ABSTRACT FROM AUTHOR]

Finite-time control theory has been widely used as a mathematical tool to design robust controllers. By manipulating the finite-time convergence proof of this theory, we developed a new control design appropriately tuned for the finite-time control of the chaotic logistics system. In this experimental setup, the logistic equation is programmed into a PIC microcontroller, and a part of the controller was conceived using analog electronics. Because the system to be controlled is in the discrete-time domain, and the finite-time stability proof is stated in the continuous-time representation, our finite-time control approach is a good example for designing control algorithms in both time domain schemes. Hence, our experimental results support our main contribution. Pulse width modulation (PWM) is the format used to translate digital signals into the continuous-time field. Therefore, the main contribution of this article is the theoretical foundations for creating a recent controller that satisfies the convergence criterion in finite time and its construction using an 8-bit microcontroller. All this contributes to the chaotic logistical map. [ABSTRACT FROM AUTHOR]

In this article, the authors present a new competitive Packed-U-cell and neutral point clamped (PUC-NPC) 9-level converter that utilizes a small number of power switches and passive components. Only seven switches are added to a single DC source. However, the proposed converter takes benefits of the neutral point clamped (NPC) converter's capability to connect capacitors in series, all with a simple control that enables the algorithm associated to the proposed inverter operate correctly in an open loop operation. A technique of pulse width modulation (PWM) is employed to maintain capacitor voltage at desired values. The proposed inverter produces an almost sinusoidal waveform output voltage, as result, a perfectly sinusoidal charge current with minimal impact on the economy and energy consumption are optioned. The converter has been integrated with a photovoltaic system to minimize its impact on the electricity supply and enhance energy efficiency. In order to take a maximum power from the photovoltaic panel, authors employ a maximum power point tracking (MPPT) technique based on disturbance and observe (P and O). When combined with the proposed control technique, it offers a competitive system suitable for standalone use or as an energy source, eliminating the need for PI regulators or additional investments. The proposed 9-level converter has been validated through simulation, utilizing the MATLAB Simulink environment to model the proposed system. Dynamics of this later were verified by changing the load charge. [ABSTRACT FROM AUTHOR]

Multilevel inverters have been forecasted in recent years for industrial and renewable energy applications due to its inherent characteristics of shaping the output voltage nearer to sinusoidal shape through concatenating several two/three level inverters using isolated DC sources or DC-link capacitors. However, the classical topologies used for synthesizing stepped voltage have several outwards like more number of DC sources or DC-link capacitors and switching devices used. In this paper, an effort has been sighted to bring a new topology for generating stepped voltage to overcome the above mentioned demerits. In addition to this, a new digital pulse width modulation (PWM) strategy is developed in-line with a new topology to eliminate the use of carrier and reference signals. The performance of the proposed topology and developed control strategy are evaluated in MATLAB/Simulink platform and an laboratory prototype is constructed for experimental investigations to accord the simulation results. [ABSTRACT FROM AUTHOR]

Photovoltaic (PV) has become an important alternative because of the increased demand for electricity and the limited supply of traditional energy sources. Harmonic distortion (HD) on the grid-connected PV can lead to several undesirable outcomes, including overheating of connected equipment, frequent grid interruptions, reduced accuracy of electrical meters, and an increase in the required current. This manuscript proposes the novel use of the Sunflower Optimization (SFO) Algorithm in grid-connected single-stage DC–AC converter with minimizing Total HD (THD) and enhancing the efficiency of the system as its primary objective. The SFO algorithm is used to maximize the system's features and control the switched inductor boost converter. The proposed technique is then simulated using MATLAB and its performance is contrasted with other existing technologies Recurrent Neural Network (RNN), Garra-Rufa Fish Optimization-Student Psychology Optimization Algorithm (GRFO-SPOA), and Fuzzy Logic Control (FLC). The proposed method attains an efficiency of 97% with a low THD of 3.1%. The findings suggest that the proposed method outperforms the existing approaches. [ABSTRACT FROM AUTHOR]

This work experimentally addresses damage calibration of an unmanned aerial vehicle in operational condition. A wide range of damage level and types are simulated and controlled by an electric motor via pulse width modulation in this regard. The measurement is carried out via established protocols of using a piezo-patch on one of the 8 arms, utilising the vibration sensitivity and flexibility of the arms, demonstrating repeatability of such protocol. Subsequently, recurrence analysis on the voltage time series data is performed for detection of damage. Quantifiers of damage extent are then created for the full range of damage conditions, including the extreme case of complete loss of power. Experimental baseline condition for no damage condition is also established in this regard. Both diagonal-line and vertical-line based indicators from recurrence analysis are sensitive to the quantitative estimates of damage levels and a statistical test of significance analysis confirms that it is possible to automate distinguishing the levels of damage. The damage quantifiers proposed in this paper are useful for rapid monitoring of unmanned aerial vehicle operations of connection. [ABSTRACT FROM AUTHOR]

Cardiac monitoring systems in Internet of Things (IoT) healthcare, reliant on limited battery and computational capacity, need efficient local processing and wireless transmission for comprehensive analysis. Due to the power-intensive wireless transmission in IoT devices, ECG signal compression is essential to minimize data transfer. This paper presents a real-time, low-complexity algorithm for compressing electrocardiogram (ECG) signals. The algorithm uses just nine arithmetic operations per ECG sample point, generating a hybrid Pulse Width Modulation (PWM) signal storable in a compact 4-bit resolution format. Despite its simplicity, it performs comparably to existing methods in terms of Percentage Root-Mean-Square Difference (PRD) and space-saving while significantly reducing complexity and maintaining robustness against signal noise. It achieves an average Bit Compression Ratio (BCR) of 4 and space savings of 90.4% for ECG signals in the MIT-BIH database, with a PRD of 0.33% and a Quality Score (QS) of 12. The reconstructed signal shows no adverse effects on QRS complex detection and heart rate variability, preserving both the signal amplitude and periodicity. This efficient method for transferring ECG data from wearable devices enables real-time cardiac activity monitoring with reduced data storage requirements. Its versatility suggests potential broader applications, extending to compression of various signal types beyond ECG. [ABSTRACT FROM AUTHOR]

A three‐level neutral point clamped (3L‐NPC) voltage source inverter (VSI) topology can be advantageous in electric vehicles with a high DC‐link voltage and a high switching frequency. A bulky DC‐link capacitor is not an option; thus, the DC‐link capacitor's sizing considering the traction system characteristics is an important design step. This paper investigates how the DC‐link capacitor size of a 3L‐NPC VSI gets affected by the combination of the interdependent characteristics of an electric drive, such as its power factor, modulation index, current, and fundamental frequency, with the effects of the modulation methods. Five pulse width modulation (PWM) methods, of which three of them have an active neutral point potential control, are compared in terms of their neutral point potential (NPP) oscillations. Then, the size of the DC‐link capacitor is determined for each PWM method so that the NPP ripple is kept under desired limits at all operating conditions. It is shown that both the modulation technique and the electric machine characteristics influence the capacitor size. For example, electric machine design modifications can introduce more than a 30% reduction in capacitor size. Finally, DC‐link and NPP oscillations with different PWM methods are experimentally validated in a scaled‐down 3L‐NPC inverter. [ABSTRACT FROM AUTHOR]