Soft-switched high step-up DC/DC boost converter for distributed generation

Abstract

Conventional boost converters are practically operated with maximum voltage gain of 5, as an extremely large duty cycle in excess of 80% results in reverse recovery problem of boost diode and large conduction losses in power devices, inductors and filter capacitors. High step-up boost converters, as required in distributed generation systems using green energy sources, are nowadays drawing prime attention of power electronics engineers. In recent years, wide research is going on to operate the switching devices under soft-switched condition, so that, the converters can be made more compact by operating at high switching frequency and simultaneously maintaining high efficiency. In present work, a new soft-switched high step-up coupled-inductor boost converter is proposed to meet the demands of distributed generation systems. Performance of the proposed converter is verified by a prototype laboratory model and behaviour of the converter is found to confirm the theoretical analysis.