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This paper presents a novel concept to extract electrolyzer characteristics using advanced power converters. By synthesizing current and voltage perturbations it becomes possible to perform measurements that are comparable to electrochemical impedance spectroscopy, a powerful technique that is now still mostly confined to laboratories. Since the new concept is more limited in terms of frequency, we have investigated in what frequency range maximum phase shifts and impedances can be observed. For traditional and advanced alkaline electrolyzers this is from hundreds of millihertz to hundreds of Hertz, which is compatible with the capabilities of advanced power converters. With a combined power supply-electrolyzer model we show that it is indeed possible to obtain the same type of information as with electrochemical impedance spectroscopy. Biggest challenge lies in the accurate measurements of impedances that are in the order of microohms. The presented concept can potentially be used for stack or even cell lifetime monitoring and can facilitate predictive maintenance. • IGBT based Power Converters can be used to add smart functionalities to Green Hydrogen production. • IGBT based Power Converters can estimate Electrolyzer model, without extra cost. • Converter constraints need to be considered; and where the information is placed in the Electrolyzer. • Characterizing Electrolyzer Model can be used for Lifetime Estimation. • Two High Power Electrolyzer are analyzed with this new concept, with positive outcome. [ABSTRACT FROM AUTHOR]

Memristors (MRs) have been used in integrated circuit design due to their nanoscale size and low power consumption. In this study, a flux-controlled binary MR emulator is designed by using off-the-shelf circuit components. Then, two MR-based multi-vibrators are constructed and applied to pulse train (PT) controlled Buck converters. Compared with traditional PT controlled Buck converters requiring two pulse train generators, only one single memristive pulse generator with controllable duty cycle is used to regulate the output voltage. To suppress the low-frequency oscillations of the PT-controlled Buck converter in continuous conduction mode (CCM), an inductor current based PT (IC-PT) control method is devised with the proposed MR-based pulse generator. Simulation and experimental results both show that the IC-PT-controlled Buck converter with the MR-based pulse generator can achieve fast transient response and minimum low-frequency voltage oscillations in the CCM. [ABSTRACT FROM AUTHOR]

This paper presents a high-gain DC-DC converter for photovoltaic (PV) applications. The proposed high gain DC-DC converter employs two coupled inductors, a voltage-lift capacitor, and two diode-capacitor multiplier cells to achieve a voltage gain of 21.11. The novel hybrid gain extension mechanism was validated by testing a 300 W prototype converter. During experimentation, it yielded an output of 380 V from an 18 V DC input and switched at 50 kHz. Because the switches in the interleaved stage are operated at a duty ratio of 0.5, the input current is ripple-free, and the switch current rating is also reduced. Owing to the location, the voltage stress on the switches was only 10.5% of the output voltage. Due to the adopted gain extension mechanisms, the voltage stress on the diodes was also reduced. The output voltage of the proposed converter is regulated by implementing a closed-loop control. In practice, the converter exhibits a good dynamic response when the line voltage and load current are subjected to step changes. The availability of a common-ground point is an additional advantage. Furthermore, the significant features of the proposed converter were validated by comparing its key parameters with many state-of-the-art converters available in the literature. [ABSTRACT FROM AUTHOR]

Decarbonization is driving power systems toward more decentralized, self-governing models. While these technologies improve efficiency, planning, operations, and reduce the carbon footprint, they also introduce new challenges. In modern grids, particularly with the integration of power electronic devices and high penetration of Renewable Energy Sources (RES) and Inverter-Based Resources (IBRs), traditional reliability concepts may no longer ensure adequate performance due to systemic restructuring. This shift necessitates new or significantly modified reliability indices to capture the characteristics of the evolving power system. Ensuring converter reliability is essential for effective planning, which requires precise, component-to-system-level modeling, as different converters impact system performance indicators. However, the existing literature in this field faces a significant limitation, as most studies focus on a singular perspective. Some examine reliability at the device-level, others at the component-level, while broader reviews in power systems often emphasize system-level analysis. In this paper, we aim to bridge these gaps by comprehensively reviewing the interconnections between these levels and analyzing the mutual influence of power converter and system reliability. A key point to highlight is that, with the rapid evolution of modern power grids, decision-makers must adopt a multi-level approach that incorporates insights from all levels to enable more accurate and realistic planning and operational strategies. Our ultimate goal is to provide an in-depth investigation of studies addressing the unique challenges posed by modern power grids. Finally, we will highlight the gaps in the literature and suggest directions for future research. [ABSTRACT FROM AUTHOR]

In this article, the linear non-equilibrium thermodynamic approach is used to mathematically describe the energy regularities of an interior permanent magnet synchronous motor (IPMSM), taking into account iron loss. The IPMSM is considered a linear power converter (PC) that is multiple-linearized at operating points with a given angular velocity and load torque. A universal description of such a PC by a system of dimensionless parameters and characteristics made it possible to analyze the perfection of energy conversion in the object. For IPMSM, taking into account iron loss, a mathematical model of the corresponding PC has been built, and an algorithm and research program have been developed, which is valid in a wide range of machine speed regulations. This allows you to choose the optimal points of PC operation according to the maximum efficiency criteria and obtain the efficiency maps for IPMSM in different speed regions. The results of the studies demonstrate the effectiveness of the proposed method for determining the references of the d and q components of the armature current for both the loss-minimization strategy at the constant torque range of motor speed and the flux-weakening strategy in the constant power range. [ABSTRACT FROM AUTHOR]

This paper presents a high-gain DC-DC converter for photovoltaic (PV) applications. The proposed high gain DC-DC converter employs two coupled inductors, a voltage-lift capacitor, and two diode-capacitor multiplier cells to achieve a voltage gain of 21.11. The novel hybrid gain extension mechanism was validated by testing a 300 W prototype converter. During experimentation, it yielded an output of 380 V from an 18 V DC input and switched at 50 kHz. Because the switches in the interleaved stage are operated at a duty ratio of 0.5, the input current is ripple-free, and the switch current rating is also reduced. Owing to the location, the voltage stress on the switches was only 10.5% of the output voltage. Due to the adopted gain extension mechanisms, the voltage stress on the diodes was also reduced. The output voltage of the proposed converter is regulated by implementing a closed-loop control. In practice, the converter exhibits a good dynamic response when the line voltage and load current are subjected to step changes. The availability of a common-ground point is an additional advantage. Furthermore, the significant features of the proposed converter were validated by comparing its key parameters with many state-of-the-art converters available in the literature.

Inverter-driven generation units (IDGUs) based on renewable energy sources (RES) are actively integrated into electric power systems (EPSs) as a part of carbon neutrality development vector. RES units based on solar energy (photovoltaic power plants (PvPPs)) connected to hydrogen-based electric energy storage system (EESS) have been being actively introduced recently. For connection of modern PvPPs and hydrogen-based EESS (HESS) to grid electric power converters (EPC) are used. Large-scale implementation of these devices causes changes of EPS dynamic properties due to properties of inverting EPCs and their automatic control systems. To study and analyze these properties mathematical modelling can be used. Software on calculation of electromechanical transients is usually used for modelling transient processes. In such software generic mathematical models are developed and used to calculate transients in EPSs with PvPPs and HESSs. These models have a number of features due to which the full range of processes accompanying implementation of PvPPs and HESSs into weak grids cannot be simulated. The paper proposes an alternative all-mode variant to model these units in EPS. [ABSTRACT FROM AUTHOR]

Microgrids are a growing segment of the energy industry, representing a paradigm shift from remote central station power plants toward more localized, distributed generation. An efficient energy management structure is essential for a DC Microgrid with a PV system combined with a Hybrid Energy Storage System (HESS) of Battery and Supercapacitor. The combined supercapacitor and battery storage system provides a quick control for the DC-link voltage. It stabilizes the system and helps achieve smooth PV power delivery to loads. The boost converter used for the PV system is controlled by a Maximum Power Point Tracking (MPPT) method to extract maximum power and maintain a constant voltage at the DC bus despite the daily change in solar power. The boost-buck converter is used to control the charging and discharging processes of the BESS to maintain a constant voltage at the DC bus. To achieve the seamless operation of DC Microgrid with HESS during the power fluctuations, this work proposes power coordination and control scheme has been proposed. To analyse the performance and efficacy of the proposed DC Microgrid with HESS are implemented in MATLAB/SIMULINK. [ABSTRACT FROM AUTHOR]

ABSTRACT In this paper, the performance of the 3Φ, 6/4 switched reluctance (SR) motor drive has been analyzed using the different power converter topologies. The main objective is to identify the most suitable converter topology for SR motor drive fed electric vehicle (EV) applications. The various power converters such as dissipative, capacitive, magnetic, and bridge converters have been reviewed in terms of operating principle and the calculation of torque ripple. To analyze the drive performance, a comparative analysis is conducted between various power converter configurations including R‐dump, C‐dump, C‐dump with freewheeling transistor (FWT), and asymmetric bridge (ASB) converter. The torque ripple is evaluated for different converters, and it has been claimed that ASB converter has less torque ripple than other topologies. MATLAB/Simulink software tool is used to validate the drive performance for various configurations. A hardware setup includes a FPGA processor of Xilinx Spartan has been embedded to verify the experimental results with the Simulink results. [ABSTRACT FROM AUTHOR]

This article presents a detailed analysis of a previously introduced boost converter based on cascaded capacitor connections. The analyzed converter maintains the same voltage gain as its conventional double-boost converter counterpart. The main advantage of the redesigned converter is that it requires smaller capacitors, rated to a lower voltage, due to the cascaded connection. This makes it suitable for various applications, including distributed generation and microgrids. This paper conducts the mathematical modeling of the converter with large signal models and the equilibrium operation in continuous conduction mode, employed to implement a control scheme. Even though the individual capacitor voltage ripple reaches high values, for voltage gains above five, the output voltage ripple is lower compared with that of other converters. The analysis also includes a comparative study with the conventional double dual boost converter. Simulations assess the proposed topology's ability to effectively minimize the switching ripple in the output voltage, even with smaller capacitors. Finally, experimental results are also provided to confirm the functionality of the proposed converters under various operational conditions, which confirm its suitability for low-voltage generator applications. [ABSTRACT FROM AUTHOR]

The increasing demand for wireless power transfer (WPT) systems for electric vehicles (EVs) has necessitated advancements in charging solutions, with a particular focus on speed and efficiency. However, power transfer efficiency is the major concern in static and dynamic wireless charging (DWC) design. Design consideration and improvements in all functional units are necessary for an increase in overall efficiency of the system. Recently, different research works have been presented regarding DWC at the power converter, coil structure and compensators. This paper provides a comprehensive review of power converters incorporating high-order compensation topologies, demonstrating their benefits in enhancing the DWC of EVs. The review also delves into the coupling coil structure and magnetic material architecture, pivotal in enhancing power transfer efficiency and capability. Moreover, the high-order compensation topologies used to effectively mitigate low-frequency ripple, improve voltage regulation, and facilitate a more compact and portable design are discussed. Furthermore, optimal coupling and different techniques to achieve maximum power transfer efficiency are discussed to boost magnetic interactions, thereby reducing power loss. Finally, this paper highlights the essential role of these components in developing efficient and reliable DWC systems for EVs, emphasizing their contribution to achieving high-power transfer efficiency and stability. [ABSTRACT FROM AUTHOR]

The solar photovoltaic system suffers from varied environmental condition and causes power losses. This paper presents a Modified Artificial Rabbit Optimization based algorithm for MPPT. The performance of the Artificial Rabbit Optimization algorithm is improved by replacing the hidden parameter in the random hiding stage with levy flight strategy. The performance of the proposed algorithm is compared with particle swarm optimization, slap swarm optimization and artificial rabbit optimization under varying environmental conditions like change in uniform irradiance to partial shaded condition to uneven shaded condition and load variation. The simulation and experimental result gives a promising result by outperforming the particle swarm optimization, slap swarm optimization and artificial rabbit optimization algorithm in terms of quick convergence and decreasing oscillation towards maximum power points. [ABSTRACT FROM AUTHOR]

Various statistical methods are employed to predict the reliability of electronic components and monitor improvements in reliability. This article conducts a comprehensive study of statistical approaches for predicting the reliability of power converters, as reported in the literature. The analysis focuses on three statistical methods: MIL-HDBK-217F, FIDES, and RIAC. Among these, the military handbook MIL-HDBK-217F has been a dominant tool for failure analysis over the past two decades. The general formulas used for failure rate analysis of power converter parts with each of the three approaches are presented. The study also reviews and discusses failure rate analysis for components and modules in power converters, both with and without fault-tolerant capabilities, as documented in the literature using MIL-HDBK-217F, FIDES, and other statistical approaches. Finally, the paper outlines the conclusions drawn from the study and highlights the main limitations of the three methods. This article serves as a resource for researchers working on fault analysis in power converters.

The increased use of renewable energy in modern power grids has led to a demand for innovative technologies that can efficiently harness intermittent energy sources. Multi-Point Absorber (MPA) systems have emerged as a promising solution for capturing wave and tidal energy sustainably. This study focuses on developing advanced control strategies for MPA systems to improve their performance and coordination in power generation and grid integration for both AC and DC networks. The research begins with a comprehensive review of MPA technologies, highlighting their challenges and opportunities. It then explores the development of control algorithms that dynamically adjust MPA parameters in real-time, optimizing energy extraction efficiency. The paper also addresses the crucial aspect of grid integration, investigating power electronics interfaces and synchronization techniques to enhance grid stability. Additionally, bidirectional power flow capabilities are discussed, enabling functions like frequency regulation and voltage control. The novelty of this work lies in the development of adaptive control algorithms for MPA systems, surpassing previous efforts by incorporating real-time data for parameter adjustments. The study demonstrates the effectiveness of these advanced control strategies through simulations and implementation, evaluating energy conversion efficiency, grid compatibility, and system reliability across various conditions compared to conventional methods. The results emphasize the significance of bidirectional power flow capabilities in achieving enhanced functionality, such as frequency regulation and voltage control. This paper provides valuable insights into optimizing MPA systems, showcasing their potential to revolutionize sustainable energy capture and integration into modern power grids.

Three LED drivers which can be used for illumination, but whose main task is the transmission of information (data) via the light of the LEDs, are explored in this paper. The converter circuits need no capacitors for the energy transformation and avoid an inrush current. The lack of necessity of electrolytic capacitors reduces cost and space. Dimming the illumination is also easy to achieve. The control concept of the converters and the generation of pulsing of the LEDs for transmitting the information (data) are explained. The converters can also be expanded to more stages to drive more LEDs with different types of information. All three converters are explained in detail; all presented circuits are built up and simulated with LTSpice. Several data transmission concepts are applied and demonstrated through simulations.

In the paper problem of power supply unbalance voltage states with the same Voltage Unbalance Factor (VUF) value for power converters is tackled. This factor is being used to assess the quality of power supply. There are many sources of voltage unbalance phenomenon such as system asymmetries and uneven distribution of demand throughout phases. Based on literature three unbalance states are presented: lines overvoltage, lines undervoltage and phase angle asymmetry. VUF value alone cannot provide information on the type of voltage unbalance state. Moreover, the same VUF percentage can be obtained for different amount of unbalanced phases. In this paper simulation experiments were conducted in order to obtain data of rectifier output voltage during different unbalance states with same VUF. Ripple, mean value and frequency components of said voltage were used in order to detect and categorise power supply voltage unbalance. Such approach does not require complex power quality measuring tools as power supply unbalance can be initially diagnosed using single voltage sensor. [ABSTRACT FROM AUTHOR]

The increased use of renewable energy in modern power grids has led to a demand for innovative technologies that can efficiently harness intermittent energy sources. Multi-Point Absorber (MPA) systems have emerged as a promising solution for capturing wave and tidal energy sustainably. This study focuses on developing advanced control strategies for MPA systems to improve their performance and coordination in power generation and grid integration for both AC and DC networks. The research begins with a comprehensive review of MPA technologies, highlighting their challenges and opportunities. It then explores the development of control algorithms that dynamically adjust MPA parameters in real-time, optimizing energy extraction efficiency. The paper also addresses the crucial aspect of grid integration, investigating power electronics interfaces and synchronization techniques to enhance grid stability. Additionally, bidirectional power flow capabilities are discussed, enabling functions like frequency regulation and voltage control. The novelty of this work lies in the development of adaptive control algorithms for MPA systems, surpassing previous efforts by incorporating real-time data for parameter adjustments. The study demonstrates the effectiveness of these advanced control strategies through simulations and implementation, evaluating energy conversion efficiency, grid compatibility, and system reliability across various conditions compared to conventional methods. The results emphasize the significance of bidirectional power flow capabilities in achieving enhanced functionality, such as frequency regulation and voltage control. This paper provides valuable insights into optimizing MPA systems, showcasing their potential to revolutionize sustainable energy capture and integration into modern power grids. [ABSTRACT FROM AUTHOR]

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The aim of this article is to improve the performance of DBD excimer lamps systems for UV production. Within this framework, our approach considers two distinct directions: the geometric dimensions of the double-barrier lamp bulb and the characteristics of the power supply. To explore these directions, a sampling of 19 bulbs of different geometries is considered, and a specially designed power supply is used, capable of controlling the shape (duration and magnitude) and frequency of current pulses injected into the plasma. A dedicated test bench, including a supervisory program that drives the power supply and collects system performance data, is used to perform parametric sweeps and guarantee measurement repeatability: the set of electrical parameters is fully explored for each lamp, and each experiment is characterized by UV emission performance and electrical generator operating conditions. Multiquadric response surfaces, used to format the results of this multi-variable exploration, reveal the most efficient directions for system optimization: increasing gas volume and, at a given operating frequency, providing the shortest possible current pulses with high amplitude can increase both UV emission and conversion efficiency. [ABSTRACT FROM AUTHOR]

This paper presents a novel methodology for correcting the state‐space averaging (SSA) modeling for DC‐DC power converters represented for fourth‐order systems operating in discontinuous conduction mode (DCM). SSA modeling has been widely employed for converters operating in continuous conduction mode (CCM), obtaining a good similarity between the switched converter and the mathematical model. In contrast, when the converters work in DCM, significant deviations between the average and RMS values imply errors in the SSA model. Hence, the proposed generalized SSA modeling methodology provides an accurate model to aid the controllers and system design. Consequently, the proposed technique can be applied to distinct fourth‐order power converters such as Zeta, Ćuk, and SEPIC in several applications. Additionally, SSA corrections can be associated with different techniques for obtaining the small‐signals representation. Simulation and experimental results and mathematical analyses that prove the feasibility and functionality of the proposal are addressed. [ABSTRACT FROM AUTHOR]

This manuscript proposes a hybrid technique for optimal energy management (EM) of fuel cell (FC) and ultra-capacitor (UC) hybrid electric vehicles (FCHEVs) under uncertainty. The proposed method is a joint execution of the Slime Mould Algorithm (SMA) and the Adaptive Neuro-fuzzy Inference System (ANFIS), otherwise called the SMA-ANFIS system. The main aim of the proposed system is to achieve and regulate the steady state of DC bus voltage with minimal steady-state error (SSE) under different load conditions by using the proposed SMA-ANFIS technique. FC supplies power during vehicular operation and it is used to regulate DC bus voltage to the chosen value and recharge, and UC supplies current optimally through the proposed technique. The optimal EMS performs and controls the power flows through the associated power converters to accomplish some power allocation and energy efficiency levels. Finally, the proposed method is done in the MATLAB platform, and the performance is compared with other methods. [ABSTRACT FROM AUTHOR]

Microgrids are designed to connect different types of AC and DC loads, which require robust power controllers to achieve an efficient power transfer. However, the effects of both AC and DC disturbances in the same type of controller make achieving stability a design challenge, especially in coupled systems where disturbances affect both the upstream and downstream in the microgrid. This paper presents an analysis of a second-order sliding-mode control (SOSMC) applied to a microgrid with direct-current (DC) and alternating-current (AC) power converters. The aim is to simulate the second-order sliding-mode control with buck converters that feed constant DC–DC and DC–AC power loads. The controller was tested in consideration of a unique sliding surface facing external disturbances, such as variations in the frequency of AC converters, sudden changes in upstream voltages, and constant power loads (CPL). The influence of the gain values (K) on the controller was also analyzed. The results show that the controller is robust regarding its sensitivity to external disturbances and steady-state error. However, the importance of the constant "K" in the model states that there exist K-limit values where if "K" is too low, a slowdown is presented, and the response against disturbances can be critical, and if is too high, an overshoot is presented in the output voltage. [ABSTRACT FROM AUTHOR]

An improved combined-mode power converter (CMPC) for a solar photovoltaic (SPV) system is presented in this paper. Ten-power electronic switches are utilised for the functioning of the converter. The proposed converter has four modes of operation: buck, boost, inverter, and mixed mode. The new CMPC topology provides a unique and complex switching sequence for implementing the mixed-mode operation. This work uses a field-programmable gate array (FPGA) for mode selection and to create PWM (MS-PWM) signals. A digital MS-PWM controller is configured to switch between improved stepped perturb and observe (ISPO) maximum-power point tracking (MPPT) and sine wave PWM (SPWM). The ISPO provides the appropriate duty cycle for buck/boost operation, while the SPWM controls the inverter operation. This work's new digital PWM control algorithm supports mode selection, PWM generation, and reconfiguring PWM generation timings. The whole framework for constructing the MS-PWM controller employs a very high-speed integrated circuit hardware description language (VHDL). Simulation and experimental results are presented, proving that the digital MS-PWM controller uses fewer resources with improved accuracy. [ABSTRACT FROM AUTHOR]

Three LED drivers which can be used for illumination, but whose main task is the transmission of information (data) via the light of the LEDs, are explored in this paper. The converter circuits need no capacitors for the energy transformation and avoid an inrush current. The lack of necessity of electrolytic capacitors reduces cost and space. Dimming the illumination is also easy to achieve. The control concept of the converters and the generation of pulsing of the LEDs for transmitting the information (data) are explained. The converters can also be expanded to more stages to drive more LEDs with different types of information. All three converters are explained in detail; all presented circuits are built up and simulated with LTSpice. Several data transmission concepts are applied and demonstrated through simulations. [ABSTRACT FROM AUTHOR]

This paper presents an examination regarding the DC–DC converter output behavior at variable loads. An example of a circuit with two-quadrant operation with different control methods is shown. The presented mathematical approach is used to determine the main output values and could have an enclosure as the calculation methodology. The examination data for the step-down circuit configuration with a single-ended output LC filter are provided. A modified excel model is used to extract the parameters for the circuit output gain at the rated frequency. The simulations of the load factor variation are shown in four different plots, where the area of the steady operation is presented. The results are derived to estimate the relationship between the circuit output and load characteristics' deviation. The converter dynamic range of the operation is determined by the presented graphics. A proper LC output filter design is essential for reducing the ripple currents and increasing the overall circuit effectivity. [ABSTRACT FROM AUTHOR]

This paper proposes an improved zero-current distortion compensation (IZCDC) method for the Vienna rectifier. The conventional zero-current distortion compensation (ZCDC) method modifies the reference voltages by adding an offset voltage to compensate for the zero-current distortion (ZCD). However, the reference voltages occasionally exceed the linear modulation region by the offset voltage added at the driving start-point of the Vienna rectifier, where the modulation index of phase voltage is relatively large. This causes a hard-start of the Vienna rectifier accompanied by a serious surge and distortion in the phase current. In this paper, the IZCDC method is proposed for achieving the soft-start of the Vienna rectifier. When the overmodulation occurs, the proposed method modifies the conventional offset voltage to the IZCDC component, which is involved in the adjustment of the variance of the phase current, only for a certain phase among the three phases. As the IZCDC component regulates the variance of the phase current to zero, surge and distortion in the phase current can be mitigated. As a result, the Vienna rectifier starts its operation softly while ensuring its normal operation in the transients. The effectiveness of the proposed method is verified through simulations and experimental results. [ABSTRACT FROM AUTHOR]

The primary side feedback can stabilize the output voltage, and improve the service life of the equipment without using the secondary winding detection error signal. The topology of active filter and the improved method of primary side feedback were adopted. The performance of active EMI filter topologies was analyzed from insertion loss and equivalent circuit,the active filter with voltage sampling and current compensation was adopted. Through describing the mechanism of primary-side feedback of sampling knee point voltage, the small signal modeling of the converter in discontinuous current mode DCM) was carried out, and the compensation network was designed to ensure the stability. The simulation and experimental results show that the active EMI filter can effectively replace the traditional filtering method, and the original side feedback method can detect and correct the output voltage fluctuation to ensure the voltage stability. [ABSTRACT FROM AUTHOR]

In the current landscape of renewable energy systems, optimizing the performance of power electronic converters is crucial for ensuring reliability. Within the realm of direct current (DC)–DC power converter systems, the differential power processing (DPP) converter holds promise. However, realizing its full potential requires meticulous system design, especially in response to varying solar irradiation levels. Poor design can result in performance degradation, leading to system damage and voltage instability due to sudden irradiation fluctuations. To address these challenges, this study investigates the performance optimization of a DPP converter enhanced with a modified switched inductor, tailored for solar photovoltaic applications. To overcome traditional control strategy limitations, we propose an innovative enhanced fuzzy logic controller (E-FLC). This controller's strength lies in its dynamic adaptability, achieved through variable duty cycle control, input parameters, membership functions, and output responses. This paper emphasizes methodological precision, particularly in applying the E-FLC to the modified switched inductor. The use of this controller significantly improves both steady-state and transient response performance compared to traditional switched inductors. It rigorously analyzes the responses of the DPP converter under steady-state and transient conditions, with and without the modified switched inductor. This analytical approach sheds light on a critical yet often overlooked aspect of photovoltaic systems. The core innovation driving this research is the adoption of the E-FLC, which outperforms the commonly used proportional–integral (PI) controller in steady-state performance and transient response characteristics. This paper goes beyond conventional converter optimization studies by introducing a holistic approach encompassing system dynamics, control strategy innovation, and performance evaluation. The proposed E-FLC represents a methodological breakthrough and a substantial improvement in converter efficiency and reliability. As renewable energy continues to reshape the global energy landscape, this research sets a new standard for harnessing the true capabilities of power electronic converters in solar photovoltaic systems. [ABSTRACT FROM AUTHOR]

The junction temperature of a power device in a natural air-cooled power converter fluctuates randomly due to the variation in airflow rate in ambient environments. Most of the existing thermal analysis methods do not pay attention to the uncertain influence of airflow on the heat-dissipation capacity of such converters, making it difficult to accurately evaluate the thermal safety of these devices. To address this issue, a thermal safety assessment method for power devices in natural air-cooled converters is proposed in this paper. In the proposed method, convective heat resistance samples of converter housing are extracted with an equivalent thermal network model and the historical operation temperature of the converter. Wavelet packet transform is used to analyze the time–frequency domain characteristics of the convective heat resistance, and Monte Carlo simulation is employed to simulate the random influence of the airflow rate on the device junction temperature. The thermal safety of power devices is assessed in the form of over-temperature probability, which is expressed by a two-variable growth function. An experimental platform is designed to validate the effectiveness of the proposed method. The results show that the proposed method can accurately estimate the over-temperature risk of a power device in a natural air-cooled converter under different ambient temperature and current levels, thus effectively improving the thermal reliability of converters. [ABSTRACT FROM AUTHOR]

In this article, the linear non-equilibrium thermodynamic approach is used to mathematically describe the energy regularities of an interior permanent magnet synchronous motor (IPMSM), taking into account iron loss. The IPMSM is considered a linear power converter (PC) that is multiple-linearized at operating points with a given angular velocity and load torque. A universal description of such a PC by a system of dimensionless parameters and characteristics made it possible to analyze the perfection of energy conversion in the object. For IPMSM, taking into account iron loss, a mathematical model of the corresponding PC has been built, and an algorithm and research program have been developed, which is valid in a wide range of machine speed regulations. This allows you to choose the optimal points of PC operation according to the maximum efficiency criteria and obtain the efficiency maps for IPMSM in different speed regions. The results of the studies demonstrate the effectiveness of the proposed method for determining the references of the d and q components of the armature current for both the loss-minimization strategy at the constant torque range of motor speed and the flux-weakening strategy in the constant power range.

This research explores an improved operation of a recently studied converter, the so-called two-phase sixth-order boost converter (2P6OBC). The converter consists of a symmetric design of power stations followed by an LC filter; its improved operation incorporates an asymmetric pulse width modulation (PWM) scheme for transistor switching, sometimes known as an interleaved PWM approach. The new operation leads to improved performance for the 2P6OBC. Along with studying the 2P6OBC, one of the contributions of this research is providing design equations for the converter and comparing it versus the interleaved (or multiphase) boost converter, known for its competitiveness and advantages; the single-phase boost topology was also included in the comparison. The comparison consisted of a design scenario where all converters must achieve the same power conversion with an established maximum switching ripple, and then the stored energy in passive components is compared. Although the 2P6OBC requires a greater number of components, the total amount of stored energy is smaller. It is known that the stored energy is related to the size of the passive components. Still, the article includes a discussion of this topic. The new operation of the converter offers more streamlined, cost-effective, and efficient alternatives for a range of applications within power electronics. The final design of the 2P6OBC required only 68% of the stored energy in inductors compared to the multiphase boost converter, and 60% of the stored energy in capacitors. This result is outstanding, considering that the multiphase boost converter is a very competitive topology. Experimental results are provided to validate the proposed concept. [ABSTRACT FROM AUTHOR]

A three-phase multilevel inverter (MLI), synthesized with 31 levels in regard to its output voltage, is used to provide the AC supply to a three-phase, squirrel cage induction motor. The gating angles required for the 30 power switches on the MLI are optimized using both the genetic algorithm (GA) and the grey wolf optimizer (GWO), in which the optimal angles are determined through solving the trigonometric equations taken from Fourier analysis to target the minimum total harmonic distortion (THD) at the MLI output. A simulation model and an experimental prototype are developed for performance analysis and validation. The results demonstrate that the MLI is effectively able to produce 31 levels of three-phase AC output voltage, with the THD not exceeding 5% when loaded with a resistive load and a three-phase induction motor. The voltage and current are measured and recorded for different loads and operating conditions, including the amount of energy consumed by the load. The results of the frequency analysis demonstrate that most of the triple harmonics, which can harm the efficiency of the inverter, are cancelled. [ABSTRACT FROM AUTHOR]

Permanent magnet synchronous motors (PMSM) are very popular in the industrial market. Recently, robots are installed to compensate for the shortage of labor. Due to the increase in motors, the number of power lines and position sensor cable wiring are increased; this increase in complicated wiring is a problem. As a method to solve these problems, power superimposition technology in the power line of a PMSM is expected to reduce the distribution cables. In this paper, the power superposition technology method, and circuit equations of mounting transformers in power lines are presented and are then verified by experiment, simulation, and linear analysis. The circuit equation is proposed as a three‐phase circuit equation, which is transformed into a dq‐circuit equation by a transformation matrix. The characteristics of the electric angular frequency versus the dq‐axis voltage demonstrated satisfactory results, with errors within 1% in linear analysis and simulation. The linear analysis and experiment are shown to be similar, although there are some errors. The validity of the circuit equations could be demonstrated by the verification results. [ABSTRACT FROM AUTHOR]

Power converters can convert the electrical energy output by power source into specific forms required by target device. They are widely used in various fields such as electrification, transportation, and power systems, and are the core components of the systems. Power converters are composed of power semiconductor devices (such as IGBTs), which are prone to failure due to abnormal conditions and aging degradation, leading to power converter faults. Therefore, over the past twenty years, extensive fault diagnosis methods for power converters have been studied and proposed. Among them, symmetry-based methods have the characteristics of rapid diagnosis speed and strong robustness, but so far there's no systemic summary of such methods. Therefore, this paper reviews the relevant research on fault diagnosis of power converters based on symmetry in recent years, analyzes the mathematical principles of these methods, and compares their diagnostic performance. In addition, two factors that may have an influence on the symmetry are pointed out. This paper provides references and suggestions for the future development and research of power converter fault diagnosis. [ABSTRACT FROM AUTHOR]

Fast switching within static converters is a key to high-efficiency operation and a source of electromagnetic disturbances that can harm the proper functioning of the converters themselves or the electronic equipment placed in their neighborhood. To characterize disturbances, engineers are mainly focused on the spectral content since the higher the switching speed, the more important the high-frequency components are. In this article, a figure of merit (FOM) independent of switching speed is proposed. It allows us to compare switching patterns produced by a gate driver to each other, using as a reference the mathematical optimum of a Gaussian pattern as well as other elementary forms for which the FOM is known. A complete implementation methodology is presented to properly use this FOM that considers an adapted sampling frequency and filtering of signals before processing in order to correctly obtain information for the optimal adjustment of a driver. [ABSTRACT FROM AUTHOR]

This article presents a new modulation technique called three-dimensional sigma–delta (3D- Σ Δ ) modulation for high-frequency three-leg four-wire voltage source converters (VSCs) that use wide-bandgap (WBG) semiconductors. These WBG devices allow for the use of high switching frequencies with a greater efficiency than silicon devices. The proposed 3D- Σ Δ technique enables operation at a variable switching frequency, resulting in a significant reduction in switching losses compared to classical pulse-width modulation (PWM) techniques. Moreover, the 3D- Σ Δ technique uses a fast-processing 3D quantiser that simplifies implementation and considerably reduces computational costs. The behaviour of the 3D- Σ Δ modulation is analysed using MATLAB/Simulink and PLECS. The experimental results performed on an active power filter that uses silicon carbide (SiC) MOSFETs demonstrate an improvement in converter efficiency compared to the conventional SPWM technique. Additionally, the experimental results show how 3D- Σ Δ allows for the compensation of harmonics and homopolar currents, thereby balancing the electrical grid currents. The experiments also show that the proposed 3D- Σ Δ modulation outperforms an SPWM technique in terms of power quality, since the former achieves a larger reduction in the harmonic content of the power grid. In conclusion, the proposed modulation technique is an attractive option for improving the performance of four-wire converters in active power filter applications. [ABSTRACT FROM AUTHOR]

In power quality applications, the long-term reliability, low maintenance cost, and low volume and weight of a STATCOM converter are of the paramount importance. The use of the series multi-level power converter topology can significantly improve both volumetric and gravimetric density as well as power conversion efficiency of the STATCOM converter. This paper presents a solution that utilizes the Novel 5 Level E Type topology for the 3-phase, 4-wire STATCOM power quality applications. A comprehensive theoretical analysis and step-by-step design process are presented and discussed in the paper. A proof of the concept prototype (12kVA $3\times 400.230$ V) has been designed, manufactured, and intensively tested and experimentally verified. The experimental results are discussed in detail and compared with state-of-the-art solutions from both academic and industrial sectors. The achieved improvements in volumetric and gravimetric density, along with ultra-high power conversion efficiency and reduced cooling effort, justifies significant benefits of the proposed topology and approach.

Direct current (DC) microgrids are becoming increasingly important due to a number of causes, including the widespread use of DC loads, the integration of solar photovoltaic (PV) and energy storage devices (ESDs), and the absence of frequency and reactive power control issues. The control of DC bus voltage, power management, effective power split among the ESDs, and state of charge (SoC) restorations are important in a DC microgrid. However, DC bus voltage control and power management are difficult since the microgrids connect several distributed generators (DGs), loads, utility grids, and ESDs to the DC bus using power electronic converters. It is imperative to properly control the DC bus voltage and manage power among the sources and loads in order to maintain the stability and reliability of DC microgrids. DC microgrids can be controlled by employing centralized, decentralized, distributed, multi-level, and hierarchical control systems to ensure safe and secure operation. Besides, advanced control techniques, such as nonlinear, robust, model predictive, artificial intelligence, and many others, are employed. This article critically reviews two main aspects of DC microgrids: voltage control and power management. The challenges and opportunities for voltage control and power management in DC microgrids are discussed. The benefits and drawbacks of various voltage control and power management methods have been thoroughly documented, making this a great resource for industry professionals and academics alike. Technical issues related to the voltage control and power management of grid-connected and islanded DC microgrids are discussed. Key research gaps are identified, which could be filled by cutting-edge technologies. Readers will benefit from this review by learning about the current state of DC microgrids voltage control and power management and the need for further research.

The increasing demand for wireless power transfer (WPT) systems for electric vehicles (EVs) has necessitated advancements in charging solutions, with a particular focus on speed and efficiency. However, power transfer efficiency is the major concern in static and dynamic wireless charging (DWC) design. Design consideration and improvements in all functional units are necessary for an increase in overall efficiency of the system. Recently, different research works have been presented regarding DWC at the power converter, coil structure and compensators. This paper provides a comprehensive review of power converters incorporating high-order compensation topologies, demonstrating their benefits in enhancing the DWC of EVs. The review also delves into the coupling coil structure and magnetic material architecture, pivotal in enhancing power transfer efficiency and capability. Moreover, the high-order compensation topologies used to effectively mitigate low-frequency ripple, improve voltage regulation, and facilitate a more compact and portable design are discussed. Furthermore, optimal coupling and different techniques to achieve maximum power transfer efficiency are discussed to boost magnetic interactions, thereby reducing power loss. Finally, this paper highlights the essential role of these components in developing efficient and reliable DWC systems for EVs, emphasizing their contribution to achieving high-power transfer efficiency and stability.

In today’s world, generating units based on renewable energy sources occupy one of the main places when it comes to the development of power systems. Modern generating units based on renewable energy sources have a power converter in their composition. On the one hand, the use of a power converter gives some advantages: no direct connection to the grid, operation in all quadrants of the PQ diagram. However, on the other hand, widespread use of renewable generation units based on power converter reduces the overall inertia of the EPS, excessive use of power electronic converters in the electric grid will cause many harmonic disturbances and create new problems for safe and stable operation of EPS. In order to ensure the reliable operation of EPS with renewable energy units based on the power converter, the power converters control system should be upgraded to meet the requirements of conventional generation as part of EPS. This paper presents the result of applying a power oscillation damping controller implemented in a power converter to improve the stability of a high-dimensional EPS. The paper presents an analysis of the effect of regulators of different topology for oscillation damping. The results of the application of the power oscillation damping regulator in the following research scenarios are presented. For a more accurate assessment of the impact of the regulator, the transient damping coefficient was calculated. In this paper, the result of using the oscillation damping controller implemented in the power converter for the PV station to improve the stability of the EPS as a whole was demonstrated. The proposed solution is based on the “deloading” strategy of the PV power station and the SI block with two-loop control. The effect of oscillation damping controller on power fluctuations was evaluated according to the AVR oscillator tuning methodology.

With the growing penetration of distributed energy resources, the traditional microgrid concept is evolving into microgrid clustering, which decomposes the distribution system into interconnected microgrids to improve stability, reliability, and efficiency. Microgrid clusters coordinate power-sharing between microgrids and the main grid, effectively reducing problems such as voltage rise, harmonics, poor power factor, reverse power flow, and conventional protection scheme failures. However, there are challenges to overcome before adopting microgrid clustering, particularly in the design aspects. This paper critically reviews the challenges in the design of microgrid clustering, categorizing multi-microgrids into different architectures based on the interconnections' layout, evaluating reported control techniques in microgrid clustering, and presenting aspects of multi-microgrid protection. Possible areas of future research are highlighted to improve the operational aspects of microgrid clusters. Ref. 3, fig. 6, tables 2.

This paper demonstrates the viability and effectiveness of a novel adaptive control approach applied to power electronic converters. A methodology based on the formulation of a Lyapunov-based approach is showcased to represent the operation of a new adaptive controller for the regulation of two power converter topologies (Buck and Boost). The models of the Buck and Boost converter topologies include the parasitic parameters that represent the non-ideal components. The basic idea of the control approach is to demonstrate adaptive stabilization for the proposed non-linear system. The most important design specification to stabilize the system is to track the reference trajectory in such a way that the error on the output variable converges asymptotically to zero. This adaptation mechanism is explicitly designed so that the asymptotic stability of the equilibrium condition is guaranteed according to the Lyapunov theorem and sensitivity theory. The details of the design algorithm are explained in the paper. The proposed control approach has been compared to other Lyapunov-based control techniques proposed in literature for the same non-ideal converters. The results show that the proposed controller provides better level of robustness and performance than the other well-established Lyapunov based controllers. To verify the effectiveness of the controller in real time, a test bench has been set up with prototypes of both converters and the controller has been implemented using the Arduino microcontroller and the control system driven through the Matlab/Simulink platform.

Large-signal stability of direct current (DC) microgrids (MGs) are required to be seriously considered when more power converters are penetrated. For DC MGs suffering from large disturbances, the power electronics at both source and load sides are operated within the voltage and current limits to ensure the stability and safety. However, no existing methods have been developed to address the non-conservative stability analysis of a DC MGs with physical variable constraints. To this end, a comprehensive is developed in this paper to analyze the large-signal stability of typical DC MGs with voltage/current and pulse-width modulation duty cycle constraints, with a low level of conservatism. First, the system-level model of a DC MG is established as the basis of stability analysis. Then, a workflow based on the Lyapunov theory and numerical integration is developed to evaluate the large signal stability with physical variable constraints. The developed stability analysis method has less conservatism than the existing methods with only one moderate computational cost. The effectiveness of the proposed strategy is validated by case studies based on a single-bus direct current microgrid.

The utilization of fuel cells (FC) in automotive technology has experienced significant growth in recent years. Fuel cell hybrid electric vehicles (FCHEVs) are powered by a combination of fuel cells, batteries, and/or ultracapacitors (UCs). By integrating power converters with these power sources, the FCHEV system can overcome the limitations of using them separately. The performance of an FCHEV is influenced by the efficiency of the power electronics converter controller, as well as the technical efficiency of the power sources. FCHEVs need intricate energy management systems (EMSs) to function effectively. Poor EMS can lead to low efficiency and accelerated fuel cell and battery degradation. The literature discusses various types of EMSs such as equivalent consumption minimization strategy, classical PI controller, fuzzy logic controller, and mutative fuzzy logic controller (MFLC). It also discusses a systematic categorization of FCHEV topologies and delves into the unique characteristics of these topologies. Furthermore, it provides an in-depth comparative study of EMSs applied in FCHEVs, encompassing rule-based, optimization-based, and advanced learning-based approaches. However, comparing different EMSs can be challenging due to the varying vehicle and system parameters, which might lead to false claims being made regarding system performance. This review aims to categorize and discuss the various topologies of FCHEVs, highlighting their pros and cons, and comparing several EMSs based on performance metrics such as state of charge (SOC) and FC deterioration. This paper seeks a deeper comprehension of the recent advancements in EMSs for FCHEVs. It offers insights that can facilitate a more comprehensive grasp of the current state of research in this field, aiding researchers in staying up to date with the latest developments. [ABSTRACT FROM AUTHOR]

This study devises an advanced single-loop output voltage control method for DC/DC converters incorporating a model-free filter, active damping, and nonlinearly designed feedback terms. The resultant output-feedback controller ensures the order reduction property and reduces both the dependence level of the system model and the number of feedback loops. There are two main features that differentiate this from extant results. First, a model-free first-order pole-zero cancellation (PZC) filter extracts the time derivative component from the output voltage measurement according to the first-order dynamics by the order reduction property without any converter model information. Second, an active damping controller forming a modified proportional-integral-derivative structure tracks the output voltage to its desired trajectory along the first-order low-pass filter dynamics by the order reduction property from the PZC, which is independent of the current feedback. Experimental evidence obtained from an actual feedback system adopting a 3-kW prototype DC/DC converter validates the effectiveness of the proposed technique, which demonstrates the capability of the current sensor fault tolerance. [ABSTRACT FROM AUTHOR]

This paper presents the minimization of total harmonic distortion in a seven-level cascaded H-bridge multilevel inverter with resistive load using the teaching–learning-based optimization algorithm. The minimization of Total Harmonic Distortion (THD)is a challenging optimization problem due to the fact that nonlinear equations are involved. Recently, bio-inspired algorithms have become very popular approaches to solving various optimization problems in different areas of engineering. For this reason, the results obtained with the Teaching–Learning-Based Optimization (TLBO)algorithm were compared with three other popular bio-inspired algorithms, the genetic algorithm, differential evolution, and particle swarm optimization. The comparative analysis, conducted by sweeping the modulation index, made it possible to obtain graphs and data on the behavior of the four analyzed algorithms. Finally, it was concluded that the TLBO algorithm is very effective and is able to solve the THD-minimization problem. Its main advantage over the other algorithms is the fact that it does not require control parameters for its correct operation in the solution of the problem.

This paper presents an examination regarding the DC–DC converter output behavior at variable loads. An example of a circuit with two-quadrant operation with different control methods is shown. The presented mathematical approach is used to determine the main output values and could have an enclosure as the calculation methodology. The examination data for the step-down circuit configuration with a single-ended output LC filter are provided. A modified excel model is used to extract the parameters for the circuit output gain at the rated frequency. The simulations of the load factor variation are shown in four different plots, where the area of the steady operation is presented. The results are derived to estimate the relationship between the circuit output and load characteristics’ deviation. The converter dynamic range of the operation is determined by the presented graphics. A proper LC output filter design is essential for reducing the ripple currents and increasing the overall circuit effectivity.

Microgrids are designed to connect different types of AC and DC loads, which require robust power controllers to achieve an efficient power transfer. However, the effects of both AC and DC disturbances in the same type of controller make achieving stability a design challenge, especially in coupled systems where disturbances affect both the upstream and downstream in the microgrid. This paper presents an analysis of a second-order sliding-mode control (SOSMC) applied to a microgrid with direct-current (DC) and alternating-current (AC) power converters. The aim is to simulate the second-order sliding-mode control with buck converters that feed constant DC–DC and DC–AC power loads. The controller was tested in consideration of a unique sliding surface facing external disturbances, such as variations in the frequency of AC converters, sudden changes in upstream voltages, and constant power loads (CPL). The influence of the gain values (K) on the controller was also analyzed. The results show that the controller is robust regarding its sensitivity to external disturbances and steady-state error. However, the importance of the constant “K” in the model states that there exist K-limit values where if “K” is too low, a slowdown is presented, and the response against disturbances can be critical, and if is too high, an overshoot is presented in the output voltage.