Soft Switched High Voltage Conversion Ratio DC DC Converters for Renewable Energy Systems

Abstract

Abstract newlineIn the recent years, leading edge technologies produces electricity from various renewable newlineenergy inputs viz. photovoltaic modules, fuel cells and wind farms, and also battery newlinebanks are powering the hybrid distributed generation network with the help of highly newlineefficient power electronic interfaces. As an integral part of the network, DC DC converters newlineare connected as a front-end to deliver the energy generated from the low-voltage newlinerenewable sources to the high-voltage dc grid. newlineTo integrate low-voltage (24and#1048576;48 V) renewable supplies and storage banks to the high newline-voltage (380and#1048576;400 V) dc bus, DC DC converters will have the real essences such as newlineunidirectional/bidirectional power flow, high voltage step-up/down capability, high conversion newlineefficiency and high power density. Voltage boosting using DC DC converters newlinehave significant contributions in the other most welcoming applications such as electric newlinemobility, aerospace technologies and many industrial critical energy needs. newlineIn advanced power conversion system, the size of power electronic converter plays a newlinevital role. Magnetic core area, winding number of turns, filtering components size newlineand heat sink area requirements are low at high switching frequency operation of the newlineconverter. Also, lower source current ripple due to continuous conduction mode operation newlinesignificantly improves the power density and efficiency of the converter. However, newlineswitching voltage stresses and corresponding losses are more at high frequency operation. newlineTo mitigate this problem, soft-switching implementation to the active devices is newlinemuch needed. newlineThe motivation of the work is to bring the improvements and innovation in the DC DC newlineconverters by investigating and developing soft-switched high voltage gain converters newlinewith minimized clamp device count, lowered component stresses, reduced input current newlineix newlinex newlineripple, lowered magnetic component size requirement, thereby obtaining high power newlinedensity, high efficiency and low cost. newlineIn this thesis, three novel soft-switched DC DC converters are pr