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A single-switch high step-up boost converter based on a novel voltage multiplier (VM) has been proposed in this study. Compared to traditional boost converter, not only the voltage conversion ratio has been increased, but also voltage stress across semiconductor devices has been decreased. Moreover, the voltage conversion ratio and voltage stress of switch of the proposed converter can be adjusted by the number of the VM cells. The control and drive circuits for the proposed converter is as simple as boost converter as there are no additional switches. Working principles and performance characteristics of the proposed converter have been analysed in detail. A 200 W experimental prototype with three VMs has been built to validate the theoretical analysis. [ABSTRACT FROM AUTHOR]

This study presents a high step-up scalable voltage multiple cell (SVMC)-based DC/DC converters, which have the features of high gain, low and adjustable components stresses and automatic input-current sharing in each input phase. In virtue of the above features, the converter is applicable for the DC collection grids for offshore wind farms. In this study, the converter in terms of working principle and property characteristics are analysed with four input phases and three SVMCs. The converter has also been evaluated in terms of the component stress and voltage conversion ratio against some other converters for high-power occasions. Moreover, a 2.5 MW simulation model and a 1.2 kW prototype were constructed for verification. [ABSTRACT FROM AUTHOR]

A non-isolated high-voltage gain dual-input DC/DC converter with a zero voltage turn-off (ZVT) auxiliary circuit has been presented. Two photovoltaic (PV) modules can be connected to the proposed converter with separate maximum power point tracking (MPPT). The cost of whole PV power generation system can be decreased significantly as a single converter is employed instead of two converters. All switches can achieve ZVT by an auxiliary circuit, and turn-off switching losses can be decreased and the efficiency of the converter can be improved. Working principle and performance characteristics of the proposed converter are analysed in detail, a dual-input maximum power point tracking control algorithm has been designed for the proposed converter. An 800 W experimental prototype has been built to verify the theoretical analysis. [ABSTRACT FROM AUTHOR]

This study presents a non-isolated high step-up DC/DC converter based on a high degree of freedom voltage gain cell (HDF-VGC). Both voltage stress of components and conversion ratio of the proposed converter could be adjusted by the number of the HDF-VGC, the current stress of the semiconductor devices can also be adjusted by the input phase numbers of the converter. Moreover, the input current of each phase are automatically balanced. These characteristics make the proposed converter very suitable for high-power and high-voltage applications, such as offshore wind power high-voltage DC transmission system. In this study, the topology construction of the proposed converter has been discussed. The operation principle and performance characteristics of the converter are analysed with four input phases and five HDF-VGCs, then the converter is simulated and a 400 W experimental prototype has been built to verify the correctness of the theoretical analysis. [ABSTRACT FROM AUTHOR]

A zero voltage turn-off high step-up DC/DC converter is presented. The conversion efficiency and power density are improved significantly by using a novel passive snubber cell, which only consists of two diodes and a snubber capacitor. The converter also provides high-voltage conversion ratio as well as low-voltage stress on switches and diodes, which make it suitable for some special industrial applications as electric-vehicle, uninterruptible power supply system or photovoltaic power generation system. The topology, operation principles and performance characteristics are analysed in detail. Moreover, a maximum 800 W experimental prototype has been developed to validate the effectiveness of the theoretical analysis, and 96.2% efficiency has been achieved. [ABSTRACT FROM AUTHOR]

This study proposes a kind of high step-up dc/dc converter with a novel voltage multiplier cell (VMC). The proposed VMC sharply reduces voltage stress on switches and diodes. Therefore, the conversion efficiency can be improved significantly. The converter also provides a wide range of voltage conversion ratios including fractional as well as VMC numbers and switch duty cycle. The topologies, operation principles, working characteristics and voltage conversion ratio are analysed in detail. A 500W experimental prototype with two VMCs has been developed to validate the effectiveness of the theoretical analysis, and the highest efficiency is 93.8%. [ABSTRACT FROM AUTHOR]