Showing papers on "Buck–boost converter published in 2017"
TL;DR: In this paper, a high-voltage gain dc-dc converter is introduced, which resembles a two-phase interleaved boost converter on its input side while having a Dickson-charge-pump-based voltage multiplier (VM) on its output side.
Abstract: A high-voltage-gain dc–dc converter is introduced in this paper. The proposed converter resembles a two-phase interleaved boost converter on its input side while having a Dickson-charge-pump-based voltage multiplier (VM) on its output side. This converter offers continuous input current, which makes it more appealing for the integration of renewable sources like solar panels to a 400-V dc bus. Also, the proposed converter is capable of drawing power from either a single source or two independent sources. Furthermore, the VM used offers low voltage ratings for capacitors that potentially leads to size reduction. The converter design and component selection have been discussed in detail with supporting simulation results. A hardware prototype of the proposed converter with ${V}_{\rm{in}}= \rm{ 20}$ and ${V}_{\rm{out}}= \rm{ 400}$ V has been developed to validate the analytical results.
155 citations
TL;DR: This paper presents a novel 400 to 12 V isolated bidirectional dc–dc converter based on a phase-shift-controlled-modified dual-active-bridge power stage, which has promising performance for low-voltage high-current applications.
Abstract: This paper presents a novel 400 to 12 V isolated bidirectional dc–dc converter based on a phase-shift-controlled-modified dual-active-bridge power stage. The proposed converter consists of a half-bridge and center tap with active clamp circuit, which has promising performance for low-voltage high-current applications. 650 V gallium-nitride high electron mobility transistors are used on the high voltage side to avoid issues encountered using Si superjunction MOSFETs in phase-shift-controlled-bidirectional power conversions. The operation principle and power transfer characteristic are obtained based on a time-domain analysis of the inductor current. Design methodology and criteria and converter's efficiency analysis are discussed. Both the analysis and experiments verify that the proposed converter is capable of achieving low power loss and high power density in soft-switching and hard-switching modes. Experimental results are presented for a 1-kW, 400 V-to-12 V dc–dc prototype converter operating at 100 kHz switching frequency. A power density of 30 W/in3 and a peak efficiency of 98.3% in a wide input/output voltage range are achieved.
149 citations
TL;DR: A novel transformerless buck-boost dc-dc converter that has simple structure and the low on-state resistance of the power switch can be selected to decrease conduction loss of the switch and improve efficiency.
Abstract: A novel transformerless buck–boost dc–dc converter is proposed in this paper. The presented converter voltage gain is higher than that of the conventional boost, buck–boost, CUK, SEPIC, and ZETA converters, and high voltage can be obtained with a suitable duty cycle. In this converter, only one power switch is utilized. The voltage stress across the power switch is low. Hence, the low on-state resistance of the power switch can be selected to decrease conduction loss of the switch and improve efficiency. The presented converter has simple structure, therefore, the control of the proposed converter will be easy. The principle of operation and the mathematical analyses of the proposed converter are explained. The validity of the presented converter is verified by the experimental results.
135 citations
TL;DR: The experimental results validate the feasibility of the proposed topology and its suitability for fuel cell vehicles.
Abstract: An input-parallel, output-series dc–dc Boost converter with a wide input voltage range is proposed in this paper. An interleaved structure is adopted in the input side of this converter to reduce input current ripple. Two capacitors are connected in series on the output side to achieve a high voltage gain. The operating principles and steady-state characteristics of the converter are presented and analyzed in this paper. A 400 V/1.6 kW prototype has been created which demonstrates that a wide range of voltage gain can be achieved by this converter and it is shown that the maximum efficiency of the converter is 96.62% and minimum efficiency is 94.14%. The experimental results validate the feasibility of the proposed topology and its suitability for fuel cell vehicles.
131 citations
TL;DR: In this article, a three-port dc/dc converter for hybrid photovoltaic (PV)/fuel cell (FC)/battery applications is presented, which comprises a conventional buck-boost and a boost converter.
Abstract: In this paper, a new three-port dc/dc converter is presented for hybrid photovoltaic (PV)/fuel cell (FC)/battery applications. The proposed structure comprises a conventional buck-boost and a boost converter. Four power switches and four diodes are employed in the proposed converter. The voltage gain of the presented converter is more than the conventional boost converter. This advantage and having two unidirectional and a bidirectional inputs make the structure a suitable power electronic interface for hybrid generation applications. In addition, there are no limitations in switching the modulation. Therefore, tracking the maximum power of the PV source, setting the FC power, controlling the battery power, and calibrating the output voltage can be equipped by controlling duty ratios of the switches. The input power sources can provide power to the load and either charge or discharge the battery individually or simultaneously. The steady-state analyses of the presented converter are discussed thoroughly in this paper. Finally, in order to validate the feasibility of the presented converter, experimental results are provided.
124 citations
TL;DR: The experimental results validate the effectiveness of the proposed energy management algorithm for the New European Driving Cycle (NEDC), which determines the currents of the converters in order to regulate accurately the power provided from the three electrical sources.
115 citations
TL;DR: In this paper, a novel ultralarge gain step-up coupled-inductor dc/dc converter with an asymmetric voltage multiplier network is presented for a sustainable energy system.
Abstract: In this paper, a novel ultralarge gain step-up coupled-inductor dc/dc converter with an asymmetric voltage multiplier network is presented for a sustainable energy system. The proposed converter contains one boost converter, one voltage multiplier network, and one passive lossless clamped circuit. In order to achieve an ultralarge voltage gain, one of the two capacitors is charged by the primary side and secondary side of the coupled inductor, then it together with the secondary side of coupled inductor provides its energy for the other capacitor in voltage multiplier network. Besides, the passive lossless clamped circuit not only recycles leakage energy but also effectively reduces the voltage stress on the main switch. By this way, the efficiency of the conversion can be improved. Moreover, the reverse-recovery problem of the diodes in the leakage inductor is alleviated. The operating principles and steady-state analyses are illustrated in detail. Then, the performance of the proposed converter is compared with existing converters. Finally, a prototype circuit at 50-kHz switching frequency with 20-V input voltage, 200-V output voltage, $N = 2$ , and 200-W output power is established in the laboratory to verify the performance of the proposed converter.
104 citations
TL;DR: In this paper, a quasi-Z-source series resonant dc-dc converter is proposed for photovoltaic module-level power electronics applications, where the shoot-through pulse width modulation and phase shift modulation are combined in a single switching stage to realize the boost and buck operating modes.
Abstract: This paper presents the high-performance quasi-Z-source series resonant dc-dc converter as a candidate topology for the photovoltaic module-level power electronics applications. The converter features a wide input voltage and load regulation range thanks to the multimode operation, i.e., when the shoot-through pulse width modulation and phase-shift modulation are combined in a single switching stage to realize the boost and buck operating modes, respectively. Our experiments confirmed that the proposed converter is capable of ensuring ripple-free 400 V output voltage within the sixfold variation of the input voltage (from 10 to 60 V). The converter prototype assembled achieved a maximum efficiency of 97.4%, which includes the auxiliary power and control system losses.
101 citations
TL;DR: In this paper, the authors proposed a new boost composite converter approach to address the dominant loss mechanisms associated with indirect power conversion, resulting in fundamental efficiency improvements over wide ranges of operating conditions.
Abstract: In a hybrid or electric vehicle powertrain, a boost dc–dc converter enables reduction of the size of the electric machine and optimization of the battery system. Design of the powertrain boost converter is challenging because the converter must be rated at high peak power, while efficiency at medium-to-light load is critical for the vehicle system performance. By addressing only some of the loss mechanisms, previously proposed efficiency improvement approaches offer limited improvements in size, cost, and efficiency tradeoffs. This paper shows how all dominant loss mechanisms in automotive powertrain applications can be mitigated using a new boost composite converter approach. In the composite dc–dc architecture, the loss mechanisms associated with indirect power conversion are addressed explicitly, resulting in fundamental efficiency improvements over wide ranges of operating conditions. Several composite converter topologies are presented and compared to state-of-the-art boost converter technologies. It is found that the selected boost composite converter results in a decrease in the total loss by a factor of 2–4 for typical drive cycles. Furthermore, the total system capacitor power rating and energy rating are substantially reduced, which implies potentials for significant reductions in system size and cost.
101 citations
26 Mar 2017
TL;DR: In this paper, a high efficiency and high power density sigma converter for 48/1V voltage regulator module (VRM) is proposed, which is a quasi-parallel converter that uses a high-efficiency unregulated converter to deliver most power to the load with small power flowing through buck converter responsible for regulating the output voltage.
Abstract: A high efficiency and high power density sigma converter for 48/1V voltage regulator module (VRM) is proposed in this paper. The Sigma converter is a quasi-parallel converter that uses a high efficiency unregulated converter to deliver most power to the load with small power flowing through buck converter responsible for regulating the output voltage. The unregulated isolated converter is LLC converter designed with matrix transformer structure integrating 4 transformers in one core structure with integrating the Synchronous Rectifiers (SRs) with the winding to minimize the termination losses of the transformer so a high efficiency can be achieved. The buck converter is designed with discrete GaN devices and PCB winding inductor to regulate the output voltage. The designed Sigma converter is 48/1V-80A achieving a power density of 420W/in3 and maximum efficiency of 93.4%.
99 citations
TL;DR: In this paper, a single-switch high step-up dc-dc converter employing a quasi-resonant operation with high efficiency and low ripple continuous input current characteristics is presented.
Abstract: This study presents a novel single-switch high step-up dc-dc converter employing a quasi-resonant operation with high efficiency and low ripple continuous input current characteristics. In order to achieve a high voltage gain, a combination of coupled inductor and switched capacitor techniques is used in the proposed dc-dc converter. Moreover, utilising a series resonance capacitor with the leakage inductance of the coupled inductor leads to a resonant circuit. Subsequently, by employing a quasi-resonant operation, the switching loss of the proposed dc-dc converter has been reduced significantly. Operational analysis, mathematical derivation, component voltage and current ratings are well demonstrated in this study. Finally, the performance of the proposed circuit is evaluated through a 200 W laboratory prototype with 25 V input voltage and 400 V output voltage. The maximum efficiency achieved at full load is 96.4%.
TL;DR: The proposed converter is designed as a series resonant converter with nominal-input voltage and operates under two additional modes: a boost converter with low- input voltage and a buck converter with high-input Voltage.
Abstract: A microconverter serves as a front-end dc–dc stage of a microinverter to convert the power from a photovoltaic module to a dc bus. These front-end microconverters require isolation, high-boost ratio, wide-input voltage regulation, and high efficiency. This paper introduces an isolated resonant converter with hybrid modes of operation to achieve wide-input regulation while still maintaining high efficiency. The proposed converter is designed as a series resonant converter with nominal-input voltage and operates under two additional modes: a boost converter with low-input voltage and a buck converter with high-input voltage. Unlike conventional resonant converters, this converter operates at discontinues conduction mode with a fixed frequency, simplifying the design and control. In addition, this converter can achieve zero-voltage switching (ZVS) and/or zero-current switching (ZCS) of the primary-side MOSFETs, ZVS and/or ZCS of the secondary-side MOSFETs, and ZCS of output diodes under all operating conditions. Experimental results using a 300-W prototype achieve a peak efficiency of 98.1% and a California Energy Commission efficiency of 97.6% including all auxiliary and control power at nominal-input voltage.
TL;DR: In this article, a single-phase, single-stage buck-boost inverter for photovoltaic (PV) systems is proposed, which eliminates common mode leakage current problem in the grid-connected PV applications.
Abstract: This paper proposes a single-phase, single-stage buck–boost inverter for photovoltaic (PV) systems. The presented topology has one common terminal in input and output ports which eliminates common mode leakage current problem in the grid-connected PV applications. Although it uses four switches, its operation is bimodal and only two switches receive high-frequency pulse width modulation signals in each mode. Its principle of operation is described in detail with the help of equivalent circuits. Its dynamic model is presented, based on which a bimodal controller is designed. Experimental results, in stand-alone and grid-connected mode, obtained with a 300-W laboratory prototype are presented to validate its performance.
TL;DR: In this article, a high step-up pulse width modulation dc-dc converter integrating coupled-induction and switched-capacitor (SC) techniques is presented, which consists of a synchronous rectification Boost unit and multiple coupled-Induction-SC units.
Abstract: In this paper, a novel high step-up pulse width modulation dc–dc converter integrating coupled-inductor and switched-capacitor (SC) techniques is presented. The proposed converter consists of a synchronous rectification Boost unit and multiple coupled-inductor-SC units. Its structure can therefore be easily extended for ultrahigh voltage gain. The diodes employed in the proposed converter can operate under soft-switching condition by utilizing leakage inductance of the coupled inductor. Low-voltage-rated transistors can be used to improve the efficiency as the voltage stress on the main switches of the proposed converter is reduced. The feasibility of the proposed converter is experimentally demonstrated by a 200 W prototype converter.
TL;DR: In this article, a quadratic boost converter is combined with a voltage multiplier cell and an output filter to offer a high-voltage gain converter with nonpulsating input and output currents.
Abstract: The need of dc–dc switching converters for power supplies with high-voltage gains has increased in the recent years due to new applications in areas as renewable energy systems, transportation, industrial, medical, and others. A quadratic boost converter is a useful topology to obtain a step-up output voltage; however, a major drawback is the presence of a higher voltage stress over the active and passive switches. In this paper, a quadratic boost converter is combined with a voltage multiplier cell and an output filter to offer a high-voltage gain converter with nonpulsating input and output currents. The expressions for the capacitor voltages and inductor currents are given, as well as the corresponding ripples that allow the proper design of the converter. The bilinear switched, nonlinear averaged and linear averaged models are derived such that the dynamical behavior of the converter is analyzed and used to design a control strategy. A step-by-step procedure is given to tune up a current-mode controller. Experimental results are shown from a prototype, which delivers an output voltage of 220 V and an output power of 300 W. Step load changes between 20% and full load are applied to exhibit the robustness of switching regulator.
TL;DR: A novel integrated synchronous buck converter for the auxiliary power supply system of electric vehicles, which achieves multiple independently regulated outputs with reduced switching components in comparison with the conventional separate buck converters is proposed.
Abstract: This paper proposes a novel integrated synchronous buck converter for the auxiliary power supply system of electric vehicles, which achieves multiple independently regulated outputs with reduced switching components in comparison with the conventional separate buck converters. In order to obtain a better understanding of the proposed converter, operational principle and performance characteristics of a simplified dual-output buck converter are introduced in detail, as an example. The analysis shows that zero-voltage-switching operation and lower conduction losses could be attained. In addition, its dynamic behavior is similar to the conventional buck converter and thus the controller design is simple. Finally, experimental results based on a prototype circuit in which two inductors are integrated into one magnetic core to achieve further reduced cost are demonstrated to verify the advantages.
TL;DR: In this paper, a new extendable multi-input step-up DC-DC converter (MISUC) topology is proposed to efficiently interface multiple (renewable/non-conventional) energy sources of different output characteristics with a common load.
TL;DR: In this paper, an electrolytic capacitor (EC) less power factor correction (PFC) light emitting diode (LED) driver with reduced current ripple was proposed, which replaced the short-life ECs with long-life film capacitors.
Abstract: This study proposes electrolytic capacitor (EC) less power factor correction (PFC) light emitting diode (LED) driver with reduced current ripple. Generally PFC LED drivers need massive ECs to diminish output current ripple. The life-span of LED driver significantly reduces due to short life-span of ECs, and hence demands for EC-less LED drivers. The proposed LED driver is composed of non-inverting buck-boost PFC converter and bi-directional converter (BDC) for ripple current cancellation which replace the short-life ECs with long-life film capacitors. The PFC converter is designed with discontinuous conduction mode in order to ensure unity power factor operation. The role of BDC is to absorb second harmonic ac ripple current of PFC converter and allow the dc current to LED load. In addition, the desired BDC output voltage (
v
cbc
) is higher than the PFC output voltage (
V
LED
) irrespective of ac source voltage, hence, simplifies the control complexity. Theoretical analysis and predictions of the system have been validated using MATLAB/Simulink simulation, and experimentally validated with a prototype of 7 W. The results evident that PFC integrated BDC provide reduced ripple current with film capacitor as compared with EC counterpart and hence increase the life-span of LED driver.
TL;DR: In this paper, a three-phase modular multilevel dc-dc converter is proposed and analyzed for power electronic transformer (PET) applications, which consists of two 3-phase inverters/rectifiers coupled via a medium frequency (MF) transformer.
Abstract: A three-phase modular multilevel dc-dc converter is proposed and analyzed for power electronic transformer (PET) applications. Similar to a dual active bridge converter, the proposed converter comprises two three-phase inverters/rectifiers, coupled via a medium frequency (MF) transformer. The modular multilevel converter structure is used in the medium-voltage side to meet the high-voltage requirements and to reduce the dv/dt stress on the MF transformer. The frequency of the voltage through MF transformer (isolation frequency) is the same as the switching frequency of the power semiconductor devices, and zero-voltage switching-ON can be achieved for all the devices. With only one three-phase MF transformer, the proposed topology can greatly simplify the transformer design compared with the existed input-series output-parallel dc-dc converter structures for PET applications. A dual-phase-shift method is presented to control the output power and to balance the submodule capacitor voltages. Simulations and experimental results are provided to validate the theoretical analysis.
05 Apr 2017
TL;DR: In this paper, the authors proposed a bidirectional single-phase single-stage ac-dc converter for electric vehicle (EV) charging application, which achieves zero current switching of primary side switches and zero current turn-ON for secondary side devices throughout the operation without any additional components.
Abstract: This paper proposes a novel bidirectional single-phase single-stage ac–dc converter for Electric Vehicle (EV) charging application. AC side of the proposed converter has current-fed half-bridge converter that is connected to the full-bridge converter on secondary side of a high-frequency transformer. Current at the input of the ac side can be regulated to realize power factor correction. The proposed converter achieves Zero Current Switching of primary side switches and zero current turn-ON for secondary side devices throughout the operation without any additional components. This paper also presents novel modulation technique and control algorithm to ensure soft switching throughout the operation range of the converter in both directions of power flow. Design equations are derived to help suitable selection of components for a given specification. Design of the converter, control strategy, and the results are presented for a 1.5-kVA converter for EV charger.
TL;DR: This paper suggests another candidate for isolated/bidirectional dc/dc converter in electric vehicle on-board charger based on PWM resonant converter (RC) by analysis of the gain characteristics and the feasibility of bidirectional PWM-RC is verified.
Abstract: This paper suggests another candidate for isolated/bidirectional dc/dc converter in electric vehicle on-board charger based on PWM resonant converter (RC). The PWM-RC has good switching characteristics but it is not adequate for bidirectional applications because it is always operated under “buck type” operation regardless of power flow directions. This problem can be solved by structure change method, which increases the converter gain into double. Also, additional technique to increase the converter gain during discharging operation is suggested by analysis of the gain characteristics. The feasibility of bidirectional PWM-RC is verified with a 6.6-kW prototype charger.
TL;DR: An adaptive voltage control scheme for the storage capacitor in the buck/boost bidirectional converter is proposed to make the storage resistor voltage adaptively decrease as the load becomes lighter.
Abstract: In this paper, an electrolytic capacitor-less ac–dc light-emitting diode (LED) driver, consisting of a power factor correction (PFC) converter and a buck/boost bidirectional converter, is investigated. The buck/boost bidirectional converter is connected in parallel with the output of the PFC converter and serves to absorb the second harmonic current in the PFC output current, leaving only a dc component to drive the LEDs. This paper proposes an adaptive voltage control scheme for the storage capacitor in the buck/boost bidirectional converter to make the storage capacitor voltage adaptively decrease as the load becomes lighter. Hence, the power losses of the buck/boost bidirectional converter could be reduced at light load. Experimental results are provided to verify the effectiveness of the proposed control scheme.
TL;DR: A new negative output (N/O) buck–boost converter is proposed, which can be applied for applications that need wide range of inverse voltage and possesses a widest voltage conversion ratio in these four converters.
Abstract: In this paper, a new negative output (N/O) buck–boost converter, which can be applied for applications that need wide range of inverse voltage, is proposed The steady-state, small-signal model and power losses of the proposed converter operating in a continuous conduction mode are analyzed Comparisons among the traditional buck–boost converter, N/O hybrid buck–boost converter and N/O self-lift Luo converter are presented, and it is found that the proposed converter possesses a widest voltage conversion ratio in these four converters Finally, a prototype is built, and the simulated waveforms from the PSIM software and the experimental results are presented for validation
TL;DR: In this article, the authors discuss about the various DC-DC converter configurations with high voltage conversion ratio utilized in DC micro-grid structures and compare them based on voltage conversion ratios, duty ratio, efficiency along with the basic operating principle.
Abstract: This manuscript discuss about the various DC-DC converter configurations with high voltage conversion ratio utilized in DC micro-grid structures. The presented DC-DC converter topologies play a major role globally in the power generation sector including micro-grid, because of its decreased number of semiconductor devices, maximum conversion efficiency, small in size and cost of manufacturing is less. In this manuscript the DC-DC converter are categorized in to isolated and Non-isolated topologies. The first group topography works with the presence of transformer and the second group works without the transformer. These converters are capable to provide the various stages of output range. Researchers utilize these converters in the area of renewable energy generation, electric vehicle, micro sources, charge pumping applications etc. Hence they also work to improve the efficiency and reliability with reduction in components numbers and economical aspect. In this manuscript, the various topography of DC-DC converter topologies utilized in micro-grid are reviewed and comparison is made based on voltage conversion ratio, duty ratio, efficiency along with the basic operating principle. This review also reveals the research gaps, current trends, and challenges in the last part.
TL;DR: This paper quantifies the performance of, and experimentally confirms, the recently proposed delta-connected CHB converter for PV applications as an alternative configuration for large-scale PV power plants.
Abstract: The cascaded H-bridge (CHB) converter is becoming a promising candidate for use in next generation large-scale photovoltaic (PV) power plants. However, solar power generation in the three converter phase-legs can be significantly unbalanced, especially in a large geographically-dispersed plant. The power imbalance between the three phases defines a limit for the injection of balanced three-phase currents to the grid. This paper quantifies the performance of, and experimentally confirms, the recently proposed delta-connected CHB converter for PV applications as an alternative configuration for large-scale PV power plants. The required voltage and current overrating for the converter is analytically developed and compared against the star-connected counterpart. It is shown that the delta-connected CHB converter extends the balancing capabilities of the star-connected CHB and can accommodate most imbalance cases with relatively small overrating. Experimental results from a laboratory prototype are provided to validate the operation of the delta-connected CHB converter under various power imbalance cases.
TL;DR: This paper presents a novel soft-switching galvanically isolated buck-boost dc–dc converter as a module-integrated converter for photovoltaic (PV) applications that features three major operating modes: boost, normal, and buck mode.
Abstract: This paper presents a novel soft-switching galvanically isolated buck-boost dc–dc converter as a module-integrated converter for photovoltaic (PV) applications. It features three major operating modes: boost, normal, and buck mode. Their proper distribution over the input voltage range enables wide voltage regulation capabilities, i.e., close to those of nonisolated power optimizers. The proposed control algorithm requires only one buck-boost switching stage that performs voltage regulation by means of the switching stage reconfiguration with smooth transition between the modes. The design guidelines and the digital control system for PV applications are provided. The module-integrated converter was verified experimentally with a solar array simulator. The converter showed good maximum power point tracking performance and a peak efficiency of nearly 97%.
TL;DR: In this paper, the authors proposed a new asymmetric half-bridge (HB) resonant converter for dc/dc power system with a wide range of low input voltage, which can mitigate the design limitation for a high efficiency.
Abstract: A new asymmetric half-bridge (HB) resonant converter for dc/dc power system with a wide range of low input voltage is proposed in this paper. The proposed converter is easily derived based on the switch integration technique, merging a buck–boost, which is the same with the active-clamp forward's primary circuit, and the HB LLC resonant converter. By adopting the buck–boost circuit in front of the HB LLC resonant converter, higher input voltage of LLC resonant converter stage can be achieved. As a result, the primary conduction loss can be significantly reduced. In addition, to cover wide input voltage range, an asymmetric pulse width modulation control is applied. It can mitigate the design limitation for a high efficiency. Moreover, the proposed converter can achieve not only the small conduction loss and the optimal design for high efficiency, but also high power density and low cost due to the switch integration technique. The validity of the proposed converter is confirmed by the experimental results of a prototype converter with 36–72 V DC input and 300 W (12 V/25 A) output.
TL;DR: The simulation and experimental results have shown that the proposed converter is more efficient than other dc/DC converter topologies to achieve higher performance and reliability of power dc/dc converters.
TL;DR: In this paper, a voltage-doubler circuit for providing high voltage gain with reduced voltage stress across the semiconductor devices is proposed for photovoltaic (PV) based grid application.
TL;DR: In this paper, a zero-ripple input-current high-step-up boost-single-ended primary inductor converter (SEPIC) dc-dc converter with reduced switchvoltage stress was proposed.
Abstract: This paper proposes a zero-ripple input-current high-step-up boost–single ended primary inductor converter (SEPIC) dc–dc converter with reduced switch-voltage stress to overcome some drawbacks of the conventional cascaded boost–SEPIC dc–dc converter. In the proposed converter, the input current ripple is significantly removed by the auxiliary circuit at the boost stage and the voltage gain is more increased by using turn ratio of a coupled inductor at the SEPIC stage. Additional, the switch-voltage stress is reduced due to the clamping circuit, and the reverse-recovery problem of the output diode is alleviated by the leakage inductor. Hence, the low-voltage-rating MOSFET, which has low $R_{{{\rm ds(on)}}}$ , can be utilized as a main switch device. Therefore, the total power efficiency is improved. The theoretical analysis of the proposed converter is verified on an output 200-V to 200-W prototype.