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Ecuador, like every country in the world, urgently requires a conversion of transportation to electric power, both for economic and environmental reasons. This paper focuses on the technical and economic feasibility of a solar-powered electric charging station equipped with battery storage in Cuenca, Ecuador. By reviewing current literature, we assess the environmental impact of electric mobility and its potential to reduce fossil fuel dependence and generate energy savings. The analysis encompasses various factors, including EV energy consumption, solar energy system sizing, energy production, and battery storage capacity. Key findings indicate that integrating solar PV systems with EV charging stations efficiently supports a reliable and sustainable energy supply. Simulation results reveal seasonal variations in solar generation, highlighting the importance of proper system sizing to maintain charging supply reliability and manage surplus generation. The economic analysis of three scenarios underscores the financial viability of implementing PV systems without battery storage, yielding a positive Internal Rate of Return (IRR) and Net Present Value (NPV). However, scenarios with battery storage present negative NPV and long investment return periods, impacting economic viability negatively. These insights underscore the need for a balanced design to ensure sustainability and economic feasibility in the transition to electric mobility. [ABSTRACT FROM AUTHOR]

A single-phase grid coupled PV system with a switched Z-source boost converter is analysed on the basis of closed-loop control using a novel hybrid algorithm. As PV results in low-voltage DC, it is vital to step up this low-voltage DC and so a suitable DC-DC converter is needed. A switched Zsource boost converter is utilized for the step-up process as this converter uses minimum passive components, thereby reducing the cost with improved power density. Control of the converter is carried out by a closed loop control using a PI controller tuned with a novel genetic-based chicken swarm (GBCS) algorithm which combines the merits of both genetic and chicken swarm able to deal with complex problems, simple with fast convergence. The output of the converter is then given to the grid through a single-phase VSI in which DC–AC conversion takes place. While connecting PV to the grid, another factor to be taken care of is grid synchronization which is accomplished by a PI controller in which the actual and reference power are analogized. The proposed control scheme is simulated in a MATLAB environment and the outcomes are observed. The grid current THD of 1.6% and reactive power compensation is accomplished. [ABSTRACT FROM AUTHOR]

With the continuous progress of new energy technology, new energy vehicles have ushered in a stage of rapid development. As the central core of new energy vehicle, the power accumulator batteries have been attracting increasing attention. To obtain the exact electrical characteristics of the power battery, battery charging and discharging are integral component. A bidirectional grid‐connected AC/DC converter with predictive load‐feedforward compensation is presented in this article. Derive a predictive load‐feedforward model from the state space model of the rear DC/DC converter to reduce the bus voltage fluctuations caused by load variations. Firstly, the system structure for battery charging and discharging system is presented, and then the underlying principle of predictive load‐feedforward control is analyzed. Secondly, the predictive load‐feedforward model is built and discussed. Finally, build a system simulation model in MATLAB/Simulink and set up an experimental platform in the lab. Simulation results show that the predictive load‐feedforward control can reduce the bus voltage fluctuation and regulation time by about 84% and 50%, respectively, when the load power varies substantially. The findings of experimental studies also indicate that with predictive load‐feedforward control can significantly suppress bus voltage fluctuations and improve the dynamic response of the converter. [ABSTRACT FROM AUTHOR]

Most coupled inductor‐based step‐up DC–DC converters encounter a significant voltage overshoot on their power switch due to the leakage inductance of the coupled inductor. So, they need additional bulky snubber circuits or a sophisticated procedure for coupled inductor design to reduce that effect. This paper proposes an improved coupled inductor‐based DC–DC converter, which provides a high quadratic voltage conversion ratio without excessive voltage stresses on the power switch. An active clamp circuit that operates with the zero‐voltage switching (ZVS) feature has been utilized for this aim. This feature allows the main power switch to be selected from low voltage ratings and low on‐resistance MOSFETs, which reduces conduction loss. The topology also benefits from continuous input current, high gain, high efficiency, and an appropriate number of components compared with the produced gain. In this article, the theory and operation of this converter are described by proposing the dc and small‐signal models, loss model, and continuous and discontinuous current modes (CCM and DCM) relations. Experimental results are represented to evaluate the performance of the proposed topology. For this purpose, a 240 V/240 W prototype has been designed and fabricated. Results confirm the above claims. [ABSTRACT FROM AUTHOR]

Summary: Maintaining proper current sharing among distributed generation (DG) units while regulating the output voltage is a challenging control issue in DC microgrids. The conventional droop control is widely used at the primary level of control to tackle this issue, but this method faces some limitations in voltage control and current sharing. To address this problem, this paper presents a new distributed secondary control method that determines the resistance of transmission lines by injecting an external pulse to the reference voltage of each converter and measuring output voltage and current changes. The proposed secondary control signal, denoted as Ui, enables simultaneous proportional current sharing and voltage restoration in the DC microgrid by correcting the droop coefficients based on the determined resistances. In order to ensure the stability of the proposed method, the small signal stability analysis of the closed‐loop system is conducted, considering various parameter changes. In contrast to similar methods, the proposed method introduces a new hybrid technique of voltage setpoint shifting and droop parameter adjustment that achieves precise proportional current sharing and voltage restoration, even when faced with varying resistive loads and constant power loads (CPLs). Additionally, the proposed method demonstrates outstanding characteristics, such as high convergence speed, the ability to determine transmission line resistances instead of assuming them to be known, and robustness in plug‐and‐play scenarios and communication system failures. The simulation results in MATLAB and experimental tests confirm the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Model predictive control (MPC) is recognized as an efficient control method for the modular multilevel converter (MMC), owing to its advantages, such as good robustness, rapid dynamic response, and multi-objective control. However, due to the coupling relationship between the ac-side current and the circulating current, the existing MPC has an impact on the ac-side current while suppressing the circulating current. In this paper, the relationship between the ac-side current performance and circulating current suppression is discussed in detail, and a three-stage MPC (TS-MPC) strategy is proposed to optimize the comprehensive performance. With the ac-side current control, circulating current control, and comprehensive optimization control, the optimum performance of both the ac-side current and circulating current suppression is realized while maintaining a low computational burden. Moreover, a grouping sorting algorithm is designed to reduce the calculation burden and to balance the capacitor voltages. The steady-state and transient performances of the proposed TS-MPC strategy have been verified by experimental results, which validates its correctness and effectiveness. [ABSTRACT FROM AUTHOR]

In this paper, a single objective variable double voltage vector model predictive control (SOV‐DVVMPC) to lower the computational burden for single‐phase cascaded H‐bridge (CHB) converters is proposed. The proposed algorithm is based on a hierarchical structure to control the grid‐connected current and capacitor voltage without a weighting factor. Firstly, layer I controls the grid‐connected current to select the optimal region, the cost function related to the voltage region is designed and the optimal state is calculated directly by analyzing the linear relationship between the divided region and its adjacent voltage levels, which can reduce the computational burden. Correspondingly, the optimal vectors are symmetrically distributed over the entire control cycle by a modulation principle, fulfilling the fixed switching frequency (FSF) of the system. Then, layer II uses redundant switching states to maintain capacitor voltage balancing. Finally, a single‐phase CHB converter experiment setup is constructed, the results show that compared with DVV‐MPC, the execution time of SOV‐DVVMPC is reduced by 26.4%, and compared with traditional MPC, the switching frequency is fixed and the output current quality is improved. [ABSTRACT FROM AUTHOR]

In this paper, an interleaved DC–DC step-up converter with improved characteristics based on a voltage multiplier rectifier is presented. The proposed converter is presented and analyzed for two different operating duty regions including operating region 1 (0 < D ≤ 0.5), and operating region 2 (0.5 ≤ D < 1). This converter can be used in various applications such as energy storage, electric vehicles, and renewable energy systems. This converter is composed of two stages: an interleaved boost stage and a voltage multiplier rectifier stage, which collectively forms its general structure. The interleaved boost stage is a type of two-phase boost converter that transforms the input DC voltage into a high-frequency AC square waveform. This waveform can be readily filtered using smaller capacitors. The square-shaped voltage waveform from the interleaved boost stage is rectified and converted to a high DC voltage by the Voltage Multiplier Rectifier (VMR) stage. The operating regions, the evaluation of the steady-state condition, the voltage gain of the proposed converter's parasitic and ideal models as well as its losses and efficiency analysis have been evaluated. The proposed converter has an efficiency of 97% at the output power of 150 W. The proposed converter is simulated to convert a voltage of 25–159.5 V and to validate the mathematical relationships and simulation results, a laboratory prototype has been developed. The simulation and experimental results show the precision of the performance of the proposed interleaved boost converter. [ABSTRACT FROM AUTHOR]

Recent advances in high-power applications employing voltage source converters have been primarily fuelled by the emergence of the modular multilevel converter (MMC) and its derivatives. Model predictive control (MPC) has emerged as an effective way of controlling these converters because of its high response. However, the practical implementation of MPC encounters hurdles, particularly in MMCs featuring many sub-modules per arm. This research introduces an approach termed folding model predictive control (FMPC), coupled with a pre-processing sorting algorithm, tailored for modular multilevel converters. The objective is to alleviate a significant part of the computational burden associated with the control of these converters. The FMPC framework combines multiple control objectives, encompassing AC current, DC current, circulating current, arm energy, and leg energy, within a unified cost function. Both simulation studies and real-time hardware-in-the-loop (HIL) testing are conducted to verify the efficacy of the proposed FMPC. The findings underscore the FMPC's ability to deliver fast response and robust performance under both steady-state and dynamic operating conditions. Moreover, the FMPC adeptly mitigates circulating currents, reduces total harmonic distortion (THD%), and upholds capacitor voltage stability within acceptable thresholds, even in the presence of harmonic distortions in the AC grid. The practical applicability of MMCs, notwithstanding the presence of a large number of sub-modules (SMs) per arm, is facilitated by the significant reduction in switching states and computational overhead achieved through the FMPC approach. [ABSTRACT FROM AUTHOR]

The cascaded H‐bridge (CHB) converter can achieve rich functions, such as active rectification, active power filtering, distributed energy storage, etc. The control of the CHB converter is a multiobjective optimization problem. Finite control set model predictive control (FCS‐MPC) is an effective method developed in recent years to solve this problem. However, because of the large amount of calculation, traditional FCS‐MPC cannot be directly used to control the multilevel CHB converter. It is also difficult to tune the weighting factors in traditional FCS‐MPC. To solve these problems, this paper proposes an improved sequential MPC (IS‐MPC) method for the CHB converter. The proposed method divides the control objectives of the CHB converter into different layers according to their priorities and the control degrees of freedom of each layer can be adjusted according to the system state. Simulation and hardware‐in‐the‐loop (HIL) implementation on a three‐phase 7‐level CHB converter shows that the proposed method can effectively control the ac current and submodule voltage of the CHB converter and reduce the switching loss. Moreover, it significantly reduced the calculation burden of traditional FCS‐MPC, and the use of the weighting factors is also avoided. © 2024 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

This study presents an advanced Model Predictive Control (MPC) technique designed to mitigate Circulating Current (CC) in HVDC systems equipped with Modular Multilevel Converters (MMC). This MPC strategy eliminates the need for traditional PI regulators and pulse width modulation, improving system dynamics and control accuracy. It excels in managing output currents and mitigating voltage fluctuations in sub-module capacitors. Moreover, the paper introduces a novel communication-free Fault Ride-Through (FRT) method that makes a DC chopper redundant, enabling rapid recovery from disturbances. To reduce the computational burden of standard MPC algorithms, an aggregated MMC model is proposed, significantly decreasing the computational complexity. Simulation studies validate the new MPC algorithm's capability in regulating AC side current, reducing CC, and ensuring capacitor voltage stability under varying conditions. The findings indicate that the proposed MPC controller outperforms traditional PI and PR-based methods, offering enhanced dynamic response, decreased steady-state error, and lowered converter losses, which contribute to smoother DC link voltages. Future research will focus on system scalability, renewable energy integration, and empirical validation through hardware-in-the-loop testing. [ABSTRACT FROM AUTHOR]

SiC devices can enhance power conversion in electric vehicles. However, traditional soldering techniques are limited by their low melting temperatures. Therefore, we used pressureless Ag sintering to assemble a 1200 V/200 A SiC metal-oxide-semiconductor field-effect transistor power module and compared the long-term reliability, electrical properties, and driving performance of the module with those of a similar module assembled using the solder Sn-3.0Ag-0.5Cu (SAC305). To assess sinter joint reliability, we performed power cycling tests over two temperature ranges, 50–150°C and 50–175°C, for 15,000 cycles. Subsequently, we compared the breakdown voltage (BVDSS) and drain-source on-resistance (RDS(ON)) of the SiC power modules and performed cross-sectional analyses of the device bonding interfaces. No difference in BVDSS was found between the Ag-sintered and SAC305-soldered joints. However, the RDS(ON) exhibited minimal variation for the Ag-sintered module but significantly varied for the SAC305-soldered module, suggesting that the former better maintained its characteristics. Furthermore, the electrical characteristics of the SAC305-soldered module underwent more significant alterations with increasing temperature change during power cycling, indicating that cracks propagated throughout the SAC305 soldered joint over time. Therefore, Ag sintering was quantitatively validated as the superior die attachment technology compared to soldering for long-term reliability. [ABSTRACT FROM AUTHOR]

With the rapid development of emerging photovoltaics technology in recent years, the application of building-integrated photovoltaics (BIPVs) has attracted the research interest of photovoltaic communities. To meet the practical application requirements of BIPVs, in addition to the evaluation indicator of power conversion efficiency (PCE), other key performance indicators such as heat-insulating ability, average visible light transmittance (AVT), color properties, and integrability are equally important. The traditional Si-based photovoltaic technology is typically limited by its opaque properties for application scenarios where transparency is required. The emerging PV technologies, such as organic and perovskite photovoltaics are promising candidates for BIPV applications, owing to their advantages such as high PCE, high AVT, and tunable properties. At present, the PCE of semitransparent perovskite solar cells (ST-PSCs) has attained 14% with AVT of 22-25%; for semitransparent organic solar cells (ST-OSCs), the PCE reached 13% with AVT of almost 40%. In this review article, we summarize recent advances in material selection, optical engineering, and device architecture design for high-performance semitransparent emerging PV devices, and discuss the application of optical modeling, as well as the challenges of commercializing these semitransparent solar cells for building-integrated applications. [ABSTRACT FROM AUTHOR]

The reliability of high-voltage power converters, which play a key role in driving electric vehicles, is becoming increasingly important owing to the rapid popularization of electric vehicles. In particular, the DC-DC converter, which plays the most basic role among the components of the power conversion system of an electric vehicle, uses a high-voltage battery as a source to properly control and provide the voltage specifications required by each electronic device, which significantly affects the electrical efficiency and performance of the vehicle. In this electrical interaction process, reliability problems such as electromagnetic waves between electronic devices and driver safety problems are crucial owing to the use of large batteries. High-voltage DC-DC converters applied to electric vehicles can be designed using various topologies. The LLC resonant topology, which can be implemented with ZVS and ZCS to minimize electrical losses in high-speed switching environments, is often used. Therefore, this study analyzes the characteristics of electromagnetic EMI-conducted emission noise under the ZVS switching operation conditions of LLC converters and presents critical factors related to the optimal design of noise reduction. [ABSTRACT FROM AUTHOR]

The design of a power electronic interface for high voltage difference DC buses is a key aspect in DC microgrid applications. A multi-port non isolated interleaved high-voltage gain bidirectional converter, which facilitates bidirectional power transfer and islanded operation in a DC microgrid, is presented in this paper. The forward high-voltage transfer ratio is achieved using a voltage multiplier circuit, and the high-gain step-down power conversion is performed using a resonant power module. A novel power transfer selection algorithm is proposed to control power flow among the interfaces of the RES, ESS, and DC grid converters, which utilizes the net power difference as the basis for switching the converter. The proposed converter is simulated for a 24 V PV source, 12 V battery, and 400 V DC grid interface using MATLAB/SIMULINK. A 200 W hardware prototype is implemented. The simulation results for voltages, currents, and power flow among RES, ESS, and microgrid DC bus proved an excellent voltage regulation, efficient power conversion, and a feasible duty cycle range with high voltage gain. These observations are validated through equivalent experimental results. A comparison is made regarding achieved gain, component sizing, achievable power transfer modes, efficiency, and control complexity with existing converters for DC microgrid applications. The presented topology proved to be a better interface with multiple-mode support with high efficiency. [ABSTRACT FROM AUTHOR]

Currently, the escalating integration of renewable energy sources is causing a steady weakening of grid strength. When grid strength is weak, interactions between inverters or those between inverters and grid line impedance can provoke widespread oscillations in the power system. Additionally, the diverse DC voltage application characteristics of power converter systems (PCS) may lead to over-modulation, generating narrow pulse issues that further impact control of the midpoint potential balance. Existing dead-time elimination methods are highly susceptible to current polarity judgments, rendering them ineffective in practical use. PCS, due to inherent dead-time effects, midpoint potential imbalances in three-level topologies, and narrow pulses, can elevate low-order harmonic content in the output voltage, ultimately distorting grid-connected currents. This is particularly susceptible to causing resonance in weak grids. To enhance the output voltage waveform of PCS, this article introduces a comprehensive compensation control strategy that combines dead-time elimination, midpoint potential balance, and narrow pulse suppression, all based on an active neutral point clamped (ANPC) three-level topology. This strategy gives precedence to dead-time elimination and calculates the upper and lower limits of the zero-sequence available for midpoint potential balance while fully compensating for narrow pulses. By prioritizing dead-time elimination, followed by narrow pulse suppression and finally midpoint potential balance, this method decouples the coupling between these three factors. The effectiveness of the proposed method is validated through semi-physical simulations. [ABSTRACT FROM AUTHOR]

Many applications, such as photovoltaic systems, uninterruptible power supplies, and automobile headlamps, need a high step-up DC–DC converter without isolation. The conventional boost converter has the advantages of simple topology and easy control. However, it has some shortcomings, such as insufficient step-up voltage ratio and poor efficiency when operating at large duty-cycle conditions. One of the popular topologies used to overcome these problems is the coupled-inductor boost converter. It utilizes the turn ratio of the coupled inductor to realize a higher step-up voltage ratio. The drawback is that the leakage inductance of the coupled inductor causes a huge voltage spike when the power switches are turned off. Moreover, because coupled inductors are characterized by their large volume and high profile, a conventional coupled-inductor boost converter is unsuited for photovoltaic systems, such as the solar microinverter. This study proposes a novel high-step-up boost converter to solve these problems. This proposed converter uses dual coupled inductors instead of the conventional coupled-inductor boost converter. The secondary side of the coupled inductor is connected in series to increase the step-up voltage ratio. The proposed converter utilizes active clamping to achieve zero-voltage switching (ZVS) for suppressing voltage spike and improving conversion efficiency. In addition, low-profile designs can be fulfilled easily for solar microinverters. The proposed converter and its control method are introduced. The operation principle, circuit characteristics, and circuit analysis are presented. A prototype converter with 300 W output power 25–40 VDC input voltage and 200 VDC output voltage was tested. All functions, including high step-up voltage ratio, ZVS, and active clamping, were achieved, and the highest efficiency was around at 94.7%. [ABSTRACT FROM AUTHOR]

This paper proposes a megawatt (MW)-scale high-voltage (HV) electrical power-conversion element for large-spacecraft electric propulsion (EP) systems. The proposed scheme is intended for long-term and crewed missions, and it is driven by a nuclear electric propulsion (NEP) that acts as a heat source. The scheme includes (i) A two-rotor generator (TRG), (ii) A rectification stage, and (iii) An isolated dual output DC-DC (iDC2) converter. The TRG is a high-reliability electric machine with two rotors, a permanent magnet rotor (PMR), and a wound field rotor (WFR). The PMR has a fixed flux and hence back-EMF, while the back-EMF due to the WFR is controlled by injecting a direct current (DC) into the WFR winding. The total TRG output voltage, which is the sum of voltages due to the PMR and WFR, is controlled over a prescribed region of spacecraft operation. The output of the TRG is rectified and connected to the input of the iDC2 converter. The iDC2 converter uses a three-winding transformer, where the primary winding is fed from the rectified output of TRG, the secondary winding processes the propulsion power to an electric thruster via a high-voltage DC (HVDC) link and a tertiary winding that is connected to the spacecraft's low-voltage DC (LVDC) power system. Three controllers are proposed for the system: an HVDC voltage controller, an HVDC current controller that controls the voltage and current processed to the thruster, and an LVDC controller that adjusts the current to the LVDC system. Detailed analytical models for the TRG, iDC2 converter, and controllers are developed and verified via simulations under different conditions. The analytical studies are further validated via results from a laboratory prototype. [ABSTRACT FROM AUTHOR]

The utilization of switched inductors, involving parallel charging and series discharging of inductors, is extensively embraced in diverse DC–DC converters for attaining high voltage gain; nevertheless, the stress on switch voltage and diode current escalates considerably with an increased count of inductors integrated into the switched inductors network. In the classical multistage switched inductor converter, the switch voltage aligns with the output voltage, and the diode experiences a high current as the number of stages increases. This research recommends a DC–DC multistage converter for energy conversion and high voltage gain with low stress. In this paper, a novel multistage switched inductor converter is introduced and designed to attain higher voltage gain while mitigating the stresses on switch voltage and diode current. The proposed circuit is created by replacing the standard multistage switched inductor converter's possible diodes with power switches. All of the switching devices are connected in such a way that the output voltage and input current are shared by all of the switches and diodes, respectively. As a consequence, the voltage stress on switches and the current stress on diodes are comparatively low, resulting in a high efficiency compared to a typical multistage switched inductor converter. It's interesting to note that the proposed converter and a typical multistage switched inductor converter both require the same amount of components. Different operation modes, analysis, a non‐ideal model, and a comparison of the suggested and recently constructed converters are discussed. The effectiveness and performance of the circuit are validated experimentally. [ABSTRACT FROM AUTHOR]

This paper introduces a cascaded symmetrical non-isolated high step-up voltage gain converter with high efficiency and low voltage stress on components combining a non-isolated buck-boost converter and voltage doubler structure. In the proposed converter, the input source is connected in series to the output load; hence, a part of the source energy is directly delivered from source to load, not through the switching branch, improving efficiency. Furthermore, the appropriately stacked voltage doubler stage not only amplifies the high step-up voltage gain ratio but also considerably diminishes the voltage stress on all semiconductor devices and capacitors. As a result, the costless low internal resistance and low voltage components can be employed for higher efficiency, higher power density, and lower cost. To demonstrate the practicality of the proposed topology, the operating principle is outlined, and the steady-state characteristics are thoroughly analyzed. Furthermore, a 360 W prototype converter has been fabricated to confirm the efficiency of the proposed converter. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have shown remarkable advancements and achieved impressive power conversion efficiencies since their initial introduction in 2012. However, challenges regarding stability, quality, and sustainability must be addressed for their successful commercial use. This review analyses the recent studies and challenges related to the operating life and end-of-life utilization of PSCs. Strategies to enhance the stability and mitigate the toxic Pb leakage in operational and recycling approaches of discarded PSCs post their end-of-life are examined to establish a viable and sustainable PSC industry. Additionally, future research directions are proposed for the advancements in the PSC industry. The goal is to ensure high efficiency as well as economic and environmental sustainability throughout the lifecycle of PSCs. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive survey on the use of artificial neural networks (ANN) for enhancing DC-DC converters in renewable energy systems, focusing on equal current sharing and voltage stability amidst the growing scarcity of electricity. The survey methodically examines literature on ANN integration with DC-DC converters, selecting studies based on their relevance to managing renewable energy efficiently, improving power distribution, and the effectiveness of ANN in addressing these challenges. The research identifies several gaps, including optimal power distribution, predictive controller limitations, and the instability of proportional-integral (PI) controls due to online training algorithm adjustments. To bridge these gaps, an innovative ANN-based control method for DC-DC converters is proposed, aimed at bolstering power generation quality, enabling flexible power distribution across microgrids, and enhancing the stability, reliability, and cost-effectiveness of renewable energy sources. Moreover, the paper discusses the correction of offline training problems, feedback error signal corrections, and integral error signals of DC-DC converters, offering new insights and solutions to overcome these technical barriers. This study underscores the converter's size and integration significance, juxtaposing traditional methods with ANN-based controls to highlight the latter's performance and efficiency advantages. Through a detailed review and proposed solutions to significant challenges in renewable energy management, this work contributes to the field's advancement by enhancing the efficiency and reliability of power systems through cutting-edge ANN-based control methods. [ABSTRACT FROM AUTHOR]

Summary: This article proposes a brand‐new high voltage gain step‐up DC‐DC converter through the amalgamation of active switched‐inductors (A‐SL) and a coupled‐inductor (CL) unit. This topology stands out due to its capacity to achieve noteworthy high voltage amplification employing a lesser amount of components when put in contrast to other comparable topologies. The voltage stress across the switches is low, which enables the utilization of low‐voltage rating switches to elevate efficiency. Moreover, the division of the input current between the switches of the converter enables the power dissipation to be diminished. The CL is utilized in a way that if the turn ratio of its windings is lessened, the voltage boost will be augmented. Furthermore, the leakage energy is recycled through the output diode; therefore, problems such as voltage spikes across the switches do not occur. Moreover, the output diode turns off naturally without reverse recovery problems. The switching pattern of the converter is simple, and both switches are driven simultaneously, and the converter can be controlled using a simple controller in a closed‐loop control method. In addition, the duty cycle range has no limitations. The operation principle and the steady‐state analysis of the proffered converter are discussed in detail for CCM and DCM. The design considerations and efficiency analysis are provided, followed by small‐signal modeling and controller design. Moreover, to evaluate the performance of the proffered converter among other topologies, a comparison study is conducted in terms of voltage gain, total device count, and voltage tension on the power switches and diodes. Finally, a 200–300 W, 28/400 V lab‐based prototype is implemented and tested to validate the analysis. [ABSTRACT FROM AUTHOR]

In this paper, we propose a method for calculating the DC source amplitude in an extended multilevel inverter (MLI) structure so that the maximum number of levels and the output voltage waveform are as close as possible to the sinusoidal wave with minimum total harmonic distortion (THD). For the developed structure, three algorithms are suggested to determine the amounts of DC voltage resources. The first important point about choosing the right amounts for the DC resources is that the number of levels should be as large as possible, and the second important point is that the intervals between the levels should be the same throughout the waveform. By observing these two points, the output voltage waveform can be as near as possible to the sinusoidal wave that we want. In this study, we used iteration-based methods to find suitable values for DC sources. Simulation results are offered to confirm the capability of the extended multilevel converter. After we solved the problem through calculation and analysis, a code was written in MATLAB with the aim that this time the code will tell us for what values of DC sources we will have the largest number of levels and as we expected, the output of the MATLAB code confirmed the correctness of the calculations. [ABSTRACT FROM AUTHOR]

Power converters are the key link to realize energy transfer from hybrid energy systems (HESs) to loads. In this paper, a family of boost and buck-boost DC-DC converters that is highly desirable for HESs is proposed and analyzed. The proposed converters possess continuous input currents that can realize small input current ripples and avoid the use of large input filters. Besides, the semiconductor counts of the proposed converters are low. Two of the converters employ single-switch double-diode while the other two adopt single-switch triple-diode. The reduced semiconductor counts greatly improve converter efficiency and system reliability. In addition, these boost and buck-boost converters have high voltage-boosting capabilities, and wide voltage gain ranges can be achieved when they are applied to HESs. Theoretical analyses and an experimental prototype are used to verify the characteristics and effectiveness of these converters. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to overcome the limitations of low efficiency, low power density and strong electromagnetic interference (EMI) of the existing pulsed melt inert gas (MIG) welding power supply. So a novel and simplified implementation of digital high-power pulsed MIG welding power supply with LLC resonant converter is proposed in this work. Design/methodology/approach: A simple parallel full-bridge LLC resonant converter structure is used to design the digital power supply with high welding current, low arc voltage, high open-circuit voltage and a wide range of arc loads, by effectively exploiting the variable load and high-power applications of LLC resonant converter. Findings: The efficiency of each converter can reach up to 92.3%, under the rated operating condition. Notably, with proposed scheme, a short-circuit current mutation of 300 A can stabilize at 60 A within 8 ms. Furthermore, the pulsed MIG welding test shows that a stable welding process with 280 A peak current can be realized and a well-formed weld bead can be obtained, thereby verifying the feasibility of LLC resonant converter for pulsed MIG welding power supply. Originality/value: The high efficiency, high power density and weak EMI of LLC resonant converter are conducive to the further optimization of pulsed MIG welding power supply. Consequently, a high performance welding power supply is implemented by taking adequate advantages of LLC resonant converter, which can provide equipment support for exploring better pulsed MIG welding processes. [ABSTRACT FROM AUTHOR]

Three-phase AC/DC pulse-width-modulated (PWM) converters have been widely employed in various renewable energy systems and industrial applications, which require a high-efficiency power converter operation. This article proposes a technique to reduce switching loss in AC/DC converters by integrating a voltage vector preselection strategy to model predictive virtual flux control. The voltage vector preselection strategy preselects available voltage vectors corresponding to switching states that lead to minimum switching loss in the phase leg, which conducts the highest current. By using preselected voltage vectors, clamping intervals are generated at every fundamental period to maintain the present switching states of the power switches, resulting in the reduction in switching loss. Additionally, by using virtual flux control, the proposed approach can effectively be used under both ideal and distorted source voltage conditions. The proposed method is compared with the conventional model predictive current control and the conventional model predictive virtual flux control. Both a simulation and experiment are performed to validate the correctness and effectiveness of the proposed method, which has been found to decrease the switching loss of an AC/DC converter by up to 15% compared to conventional control schemes at a negligible increase in the input current total harmonic distortion and DC output voltage ripple. [ABSTRACT FROM AUTHOR]

The isolated DC/DC converter plays an irreplaceable role in the development of the DC microgrid. However, the multiple discrete high‐frequency transformers occupy considerable volume in power converters due to the connection of multiple isolated converters. In order to reduce the number of discrete transformers and increase the power density as well as the reliability of the power converter, a three‐port isolated DC/DC converter with a decoupling magnetic integrated high‐frequency transformer (DMIHFT) is proposed for the DC microgrid in this paper. The semiconductor count of the proposed converter is reduced by combining one DAB converter and two LLC converters. Three discrete transformers are integrated into a single common core, and magnetic decoupling is achieved among each transformer by rational design at the same time. In addition, the magnetic circuit model derivation process of the proposed DMIHFT and the operation principles of the converter are described in detail. The design guidance of the proposed DMIHFT is present. And then, a 15 kW/20 kHz DMIHFT is designed based on the design guideline, and the simulation is carried out. Finally, a 15 kW/20 kHz DMIHFT prototype is fabricated, and the effectiveness of the proposed DMIHFT is verified by experimental results. [ABSTRACT FROM AUTHOR]

The restoration control of the modern alternating current–direct current (AC–DC) hybrid power grid after a major blackout is difficult and complex. Taking into account the interaction between the line‐commutated converter high‐voltage direct current (LCC‐HVDC) and the AC power grid, this paper proposes a novel optimization method of restoration path to reconfigure the skeleton network for the blackout power grid. Based on the system strength, the supporting capability of the AC power grid for the LCC‐HVDC is first analysed from the aspects of start‐up and operation of LCC‐HVDCs. Subsequently, the quantitative relationship between the restoration path and the restoration characteristic of LCC‐HVDC is derived in detail based on the system strength indices of the short‐circuit capacity and the frequency regulation capability. Then, an optimization model of restoration path considering non‐tree paths is formulated and a feasible optimization algorithm is proposed to achieve the optimal path restoration scheme. A modified IEEE 39‐bus system and a partial power grid of Southwest China are simulated to show that the proposed method is suitable for the restoration of AC–DC power grids and can improve restoration efficiency. This research can be an important guidance for operators to rapidly restore the AC–DC power grid. [ABSTRACT FROM AUTHOR]

The switched‐inductor‐based voltage lift converters offer high voltage gain. However, their input current has step changes due to switched‐inductor configuration and is peaky due to the voltage lift capacitor charging current. This article proposes a new high‐gain DC‐DC converter where an additional boost converter cell is incorporated in a conventional voltage lift boost converter to charge the voltage lift capacitor with a constant current, avoiding a peaky charging current from the supply. The operating principle of the proposed converter demands phase‐shifted switching signals to achieve high voltage gain and reduce ripple in the input current. High‐gain, continuous input current, positive output voltage, common ground between input and output ports, and low voltage stress on active switches are the major characteristics of the proposed converter. The operating principle, steady‐state analysis, and control design have been discussed in detail. A 200 W, 30 V/300 V, and 50 kHz laboratory prototype is developed to validate the operation of the proposed converter. [ABSTRACT FROM AUTHOR]

This paper presents a novel current-mode true RMS–DC converter based on the dynamic translinear principle. The converter is designed using a third-order translinear loop, resulting in a very compact and simple circuit. The proposed circuit is designed in 65 nm CMOS technology, operates with 1 V power supply, has only 14 transistors and performs satisfactorily over a wide input current range of 300 nA–950 nA and for a frequency range of 600 Hz–650 kHz for a capacitance value of 10 nF. The frequency range of operation can be tuned by varying the external off chip capacitor and the bias current. The circuit consumes 20 nW static power, 1.6 μW maximum dynamic power and offers the lowest FOM among the other RMS–DC converter circuits presented in the literature. Comprehensive mathematical analysis along with the post layout simulation results confirm the validity of the proposed circuit. To test the use of converter in real world scenarios, the proposed converter is introduced within a typical ECG detection system and the results show that the circuit is an attractive solution for RMS–DC conversion in low-voltage low-power applications. [ABSTRACT FROM AUTHOR]

This paper is concerned with discrete-time integral sliding mode observer (DISMO)-based predictive control to regulate the photovoltaic integrated DC–DC Buck Converter (PVBC) output voltage. First, we considered the variations in the generated voltage of the PV panel from its equilibrium point due to environmental conditions as disturbances and formulated the state-space representation of PVBC. Based on this model, we proposed DISMO, which involves the development of a novel injection term in its structure to estimate the inductor current and the voltage of the photovoltaic (PV) panel. Further conditions for the existence of such an observer are given. Second, we developed the DISMO-based predictive control using precise predictions of the output voltage by incorporating these estimates from DISMO to achieve the regulated output voltage of PVBC. Finally, we demonstrated the procedure for designing DISMO and performed simulations to validate and compare the results of the proposed DISMO-based predictive controller with that of the proportional-integral-based controller. [ABSTRACT FROM AUTHOR]

In the traditional technique of power conversions used for electric vehicles battery recharging from solar photovoltaic, a boost converter is utilized in the initial stage, continued by a full-bridge converter with a distinct switch design. However, the circuit's parasites contribute significantly to power losses, which detract from performance. This paper proposes a highly efficient power converter for charging an electric vehicle battery from solar photovoltaic. A high-gain improved quasi-Y-source DC–DC step-up converter operating at a low-duty ratio is implemented at the first stage to offset power losses at various conversion stages. In the next stage, the phase-shifted full-bridge converter incorporates the zero-voltage transition technique to consider circuit parasites and isolate the source and load with an isolation transformer. The extracted system voltage from SPV is 50-V DC, which is boosted to 150 V for charging a battery bank of 60 V, 16 Ah, by a specified power range of 1 kW. An experimental design of 0.5 kW is developed, and its performance is evaluated to illustrate the technical value of the proposed converter. Simulation results show an efficiency of 92.6% with 74 watts loss, while hardware results show an efficiency of 91.8% with 41 watts loss. [ABSTRACT FROM AUTHOR]

The primary objective of this paper is to address the adverse effects of active power fluctuations on grid-connected converters. One of the challenges in integrating high levels of solar photovoltaic power into the utility grid is the lack of inertia from converter-based resources. This paper proposes a solution to this challenge by synthesizing additional inertia and damping properties using power electronics converters. They emulate the inertia and damping properties of synchronous generators. The paper discusses different approaches to achieving effective damping control in grid-connected converters. It proposes a genetic algorithm optimization tool to optimize virtual damping and inertia parameters. The goal is to suppress oscillations and ensure stable grid operation. The proposed method is evaluated in both time-domain and frequency-domain analyses. The simulation results demonstrate the validity of the optimization technique and implementation procedure. Using virtual inertia and damping properties ensures stable grid operation and improves the integration of solar photovoltaic power into the utility grid. The paper provides a detailed discussion of the approach, optimization tool, and simulation results, highlighting the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

The application of modular multilevel converters (MMCs) to large drive systems is subject to severe low-frequency operation restrictions. The fluctuation of capacitor voltage and the high amplitude of common mode voltage in sub-modules is a thorny problem. In this paper, a novel fly-across capacitor modular multilevel converter topology is adopted to eliminate low-frequency voltage ripples by using the fly-across capacitor as a power transfer channel between the upper and lower bridge arms of the MMC. A novel finite compensation method is proposed--instead of the traditional full compensation method--that introduces a real-time variable limiting factor to change the amplitude of the mixed injected high-frequency differential-mode voltage and high-frequency differential-mode current and reduce the amplitude of the common-mode voltage on the AC side while lowering the current stress of the power devices. Finally, a complete system simulation model is constructed, and the topology with the proposed control strategy are verified to have good output characteristics under different operating conditions; good results are achieved in suppressing the sub-module fluctuation and common-mode voltage. [ABSTRACT FROM AUTHOR]

High voltage direct current (HVDC) systems provide important advantages; among them the ability to transmit enormous amounts of electrical power over great distances at low cost. As a result, planners of power systems consider it as a viable choice for power transmission and interconnection of asynchronous networks. Depending on HVDC grids, continental/super grids have been recently constructed to promote global economic development. The study described in the paper focuses on the behavior of a voltage sourced converter (VSC) based HVDC transmission system comprising three arms-neutral point clamped (NPC) converters interconnecting two asynchronous alternating current (AC) networks. In addition, the system components, and the vector control strategy of active/reactive powers and direct current (DC) bus voltage are simulated in MATLAB/Simulink under varying situations by adjusting the controller's settings. The study records and analyzes AC/DC voltages and active/reactive powers at two converter stations under varying power and voltage conditions. The results of the study provide key performance indicators, such as settling time (tsett), steady state error (SSE), overshot/undershoot (OS%/US%), and correlation factor (CF), which demonstrate the robustness of the system's control. [ABSTRACT FROM AUTHOR]

A great number of switching power supplies are used to provide a variable voltage for resistive‐inductive loads. However, some applications in industry, require a regulated current with a constant voltage such as battery charging systems, LED drivers, and laboratory equipment for power converters connected to PV cells. Additionally, some constant voltage systems are intrinsically unstable, and therefore, they cannot be used without a closed‐loop compensatory circuit. Hence, this article describes a novel smooth starter system behaving as a current source for constant voltage applications. The proposed technology is implemented by a quadratic buck converter, and then, a self‐oscillating control technique is applied for performing the output current regulation of the converter, which is capable of aiding to improve the system performance, stabilize the overall system, protect the converter from transient current oscillations, and provide an acceptable control performance. In addition to practical aspects, soft starter methods and limitation of the constant voltage power converter are mentioned and described in this article. The designed structure has not only the advantages of smooth response and simplicity to construct but also performs a nearly zero steady‐state error regulation. The power stage, the control scheme, and the modulator are explained in detail and validated by experiments. [ABSTRACT FROM AUTHOR]

Summary: In light of the increasing share of renewable energy sources (RES) in electricity generation, the research community is directing their attention toward developing highly efficient DC‐DC high‐gain step‐up converters. These converters are designed to exhibit reduced voltage stress on the switching devices (semiconductors). This paper presents a comprehensive study of a switch voltage stress‐reduced step‐up converter that offers a range of additional features, including the availability of a common ground point, continuous input current, simple two‐mode continuous conduction mode (CCM) operation, wide duty cycle range, and quadratic boosting factor. To achieve the aforementioned features, the converter utilizes two switches with the same operating modes, eliminating the need for complex switching circuitry. Operational modes, steady‐state analysis, and design considerations have been presented in detail. Comparative analysis indicates that the voltage conversion ratio per number of devices in the proposed topology is significantly higher than that of similar topologies. In addition, the voltage stress of switches is considerably less than the topologies addressed in the literature. The study further includes detailed mathematical and experimental analyses, small signal analysis, and hardware implementation to support the theoretical findings. The converter's efficiency has been thoroughly analyzed along with thermal analysis to ensure its reliability. [ABSTRACT FROM AUTHOR]

In this paper, a new high step-up converter with a simple structure is presented. The auxiliary circuit of the proposed converter is in the form of active clamp, which provides soft switching condition under zero voltage for the main and auxiliary switches, hence the converter has high efficiency. Since the auxiliary switch added in the converter works as an active clamp and has a complementary command with the main switch, the proposed converter is not complicated in terms of the control circuit and does not need to design a new control circuit. This converter has a high voltage gain that provides a high output voltage with a lower duty cycle, so it is suitable for a new energy production system such as a solar system. The proposed converter has been fully analyzed and in order to prove the theoretical analysis, an experimental prototype has been implemented and tested at a power of 500 W, which in this power an efficiency of about 97.3% has been obtained. [ABSTRACT FROM AUTHOR]

For bidirectional grid‐connected DC/AC converters, the power flow variation substantially alters the system stability, and especially severs under heavy load. Towards this problem, this paper proposes a novel impedance uniform control method to eliminate the stability degradation under power flow variations, which is achieved by reshaping the converter negative incremental impedance to resistive in the stability fragile mode. The d‐axis voltage perturbation is extracted to dynamically modify the active power current reference. Hence, the system bidirectional damping performance can be simultaneously improved by this dedicated design. Without switching control modes or sacrificing dynamic performance, the grid‐connected converter system can maintain satisfied stability under bidirectional power flow variations. Finally, the effectiveness of the proposed control method has been validated by both simulations and experiments. [ABSTRACT FROM AUTHOR]

A new high-boost converter derived from a charge-pump capacitor-based dual-boost converter is presented herein. Compared with the existing charge-pump capacitor-based dual-boost inductor converter, this structure adds an additional voltage-doubling circuit and additional coil to the original circuit to increase the voltage conversion ratio and winds the three coils around the same magnetic element. By this way, the overall size of the circuit can be reduced, and the leakage energy of the coupled inductor can be recovered. In this paper, the proposed new high-boost converter is firstly explained and analyzed, followed by simulations to demonstrate the feasibility of the proposed circuit and finally the experimental results to verify its effectiveness. [ABSTRACT FROM AUTHOR]

A new combined boost-Cuk-forward (CBCF) converter with ripple-free input current and low switch voltage stress is proposed for high step-up applications. Two coupled inductors are applied to achieve low switch voltage stress as well as balanced dc-link voltages, wherein the former is placed in series with the boost diode, and the latter is formed as a forward converter. Because these inductors are coupled with the output Cuk inductor, a ripple-free input current is also attained. The proposed converter is run at discontinuous conduction mode (DCM) by applying a low output-side Cuk inductance to reduce the switching loss by providing a ZCS turn-on of MOSFET and removing the diode reverse recovery current. In addition, the proposed converter does not have a problem with ground leakage current. The practical results verify the performance and effectiveness of the proposed CBCF high step-up converter. [ABSTRACT FROM AUTHOR]

Summary: This study develops a novel DC‐DC converter with an extremely high voltage conversion ratio that utilizes just one switch, a voltage multiplier circuit (VMC), and a coupled‐inductor. Two diodes and two capacitors comprise the VMC, employed to reach high voltage gain. Consequently, the conduction loss is minimized by using a low voltage rated switch with lower RDS(on). Due to the coupled inductor's leakage inductance, the output diodes' reverse recovery trouble is solved. Moreover, the passive clamp technique stores and recycles leakage energy at the output. The proposed DC‐DC converter features are high conversion ratio, low maximum voltage on semiconductors, remarkable efficiency, the existence of only one active low voltage switch, and simple circuit topology with common ground between the input and the output. This paper outlines CCM, BCM, and DCM's operating concept and steady‐state analysis in great detail. Furthermore, the suggested structure's capability is indicated by mathematical analysis and comparative findings with other earlier structures. Eventually, experimental findings with 210 W output power and 25 kHz switching frequency demonstrates that the proposed converter can be used successfully. [ABSTRACT FROM AUTHOR]

This paper proposes a novel interleaved ultra‐large gain zero‐voltage switching (ZVS) DC–DC converter for renewable energy systems. By using coupled inductor (CI) and built‐in transformer (BIT), a high‐voltage gain is achieved. The secondary windings of the CIs are connected in series with the primary winding of the BIT and the secondary winding of the BIT is inserted in voltage multiplier cell (VMC). In such a case, the voltage gain is proportional to the multiplication of the turn's ratios of the CI and BIT. To increase the devices' utilization, the active clamp circuit not only provide ZVS performance for the metal‐oxide‐semiconductor field‐effect transistor (MOSFETs) and recycles the leakage energy, but also participates in voltage gain enhancement. The voltage stress across the switches is considerably decreased and the low duty cycle reduces the conduction and switching losses. Low input current ripple, equal current sharing without a dedicated controller and common ground are the other merits of the proposed converter. Steady‐state analyses are presented and through a fair comparison, the superiority of the proposed converter over the state‐of‐the‐art is guaranteed. Finally, a 500‐W laboratory prototype with 20‐ to 400‐V voltage conversion is built to demonstrate the effectiveness of the proposed converter. [ABSTRACT FROM AUTHOR]

This work presents a control strategy for integrating an offshore wind farm into the onshore electrical grid using a high-voltage dc transmission system based on modular multilevel converters. The proposed algorithm allows the high-voltage DC system to operate in grid-connected or stand-alone modes, with the second case supplying power to local loads. In either mode, the modular multilevel rectifier works as a grid-forming converter, providing the reference voltage to the collector network. During grid-connected operation, the modular multilevel inverter regulates the DC link voltage while the generating units are controlled to maximize power extracted from the wind turbines. Conversely, in the event of grid disconnection, the onshore modular multilevel converter takes over the regulation of the AC voltage at the point of connection to the grid, ensuring energy supply to local loads. Simultaneously, the generator controller transitions from tracking the maximum power of the wind turbines to regulating the DC link voltage, preventing excessive power injection into the transmission DC link. Additionally, the turbine pitch angle control regulates the speed of the generator. Mathematical models in the synchronous reference frame were developed for each operation mode and used to design the converter's controllers. A digital model of the wind power plant and a high-voltage dc transmission system was implemented and simulated in the PSCAD/EMTDC program. The system modeled includes two groups of wind turbines, generators, and back-to-back converters, in addition to a DC link with a rectifier and an inverter station, both based on modular multilevel converters with 18 submodules per arm, and a 320 k V /50 k m DC cable. Aggregate models were used to represent the two groups of wind turbines, where 30 and 15 smaller units operate in parallel, respectively. The performance of the proposed control strategy and the designed controllers was tested under three distinct scenarios: disconnection of the onshore converter from the AC grid, partial loss of a wind generator set, and reconnection of the onshore converter to the AC grid. [ABSTRACT FROM AUTHOR]

Modular multilevel converters (MMCs) are widely used in voltage-sourced, converter-based high-voltage DC systems due to their modular design, scalability, and fault tolerance capabilities. In MMCs, multi-variable control objectives can be employed by using model predictive control (MPC) due to its fast dynamic response and ease of implementation. Nonetheless, conventional MPC techniques for MMCs have shortcomings, including high computational requirements, poor circulating current, and capacitor voltage fluctuation suppression. First, this study proposes an adaptive MPC technique that adapts the number of candidate combinations to the steady and transient states, significantly reducing the computational burden. Second, an improved hybrid combination of an MPC with a proportional-resonance (PR) controller enhances the circulating current and capacitor voltage fluctuation suppression performance. According to the phase difference between the circulating current and the capacitor voltage, the circulating current and capacitor voltage can be suppressed at different times by changing the circulating current reference of the PR controller. The switching frequency can be reduced by using the PR controller's output to adjust the input submodule number instead of changing the duty cycle. The proposed techniques were validated by simulations and experimental case studies with a three-phase grid-connected MMC. [ABSTRACT FROM AUTHOR]

This paper presents a novel topology of a modified isolated single-ended-primary-inductance converter (SEPIC) with a model predictive control (MPC) approach applied to direct current (DC) electronic loads. The proposed converter uses an actual transformer rather than a coupled inductor for isolation between the source and the load. The transformer allows the proposed converter to operate at a higher switching frequency, ultimately reducing the passive components' size. A low-power hardware prototype is developed and tested with a model predictive control algorithm under variable input voltages and load conditions. The performance of the proposed converter is demonstrated to be satisfactory under steady state, as well as sudden input voltage transients. The proposed converter utilizes a switched capacitor technique to generate alternating current in both windings of the transformer. As the coupled inductor is eliminated from the circuit, the problem of high voltage spikes occurring due to leakage inductances is also eliminated for the proposed converter. Therefore, the proposed converter can be used for isolated medium power applications. The experimental results show that the efficiency of the proposed converter reached 96%. The MPC allows this converter's DC voltage level to remain stable even as the input voltage and output terminal load change. Lastly, this converter with an MPC approach can be applied to different DC electronic loads, improving DC power quality and DC electronic load life. [ABSTRACT FROM AUTHOR]

Summary: This paper proposes a single‐ended primary‐inductor converter (SEPIC)‐based DC‐DC converter with higher voltage gain, continuous input current, and lower voltage stress. Suggested converter uses three‐winding coupled inductors and voltage multiplier for boosting function. The proposed structure stores lower amount of energy due to lower current magnitudes of used inductors. Moreover, using voltage multiplier reduces the voltage stress of the elements connected to the output terminals of the proposed converter. By reducing the voltage stress, in addition to reducing the rating of output elements and costs, the overall efficiency will also be increased. Also, a clamping circuit is used to diminish the voltage stresses on power switch. In order to represent the advantages of the proposed converter over some other converters in the viewpoints of the number of the used elements, continuity of input current, voltage gain, the voltage stress on power switch, and output diode, a comparison study is provided. To validate the practicability of the proposed converter, a 200‐W prototype is implemented and the experimental results are provided. [ABSTRACT FROM AUTHOR]

A high step‐down direct current‐direct current (DC‐DC) buck converter with a coupled‐inductor in its topology is presented in this study. The switching pattern of the proposed converter is interleaved; therefore, the voltage stress on the semiconductors and the components is low since the primary high voltage will be divided between the blocking capacitors on the primary side. Thus, the voltage stress on semiconductor elements will be low. As a result, the preselected elements can be chosen with low voltage ratings. In addition, there are cells with coupled inductors utilized in the structure that helps the converter to provide improved voltage gain in its output terminal. Typically, narrow duty cycles are needed to achieve high gain in conventional buck converters, but the proposed converter has obtained a high conversion ratio even with wider duty ratios. Besides, the proposed converter has a constant equation for the voltage gain for the whole range of duty cycles. Theoretical analysis and comparison with other recent converters of similar types have been conducted to demonstrate the proposed converter performance. Furthermore, to verify the theoretical analysis, a 600 W prototype of the proposed converter with 820 V/30 V is implemented, and experimental results are presented. [ABSTRACT FROM AUTHOR]