Coupled Inductor Based Soft Switched Interleaved DC-DC Converter for PV Applications

Abstract

Interleaved DC-DC converter topologies are gaining popularity for their use as an interface between photovoltaic (PV) source and load. In this paper, a family of coupled inductor (CI) based novel soft switched interleaved DC-DC converter topologies has been proposed to be used for PV application. The topology has been developed from the interleaved stage so as to reduce the input current ripple. The CI stage has been introduced to enhance the power handling capability of the converter. In addition, diode-capacitor multiplier (DCM) cells are connected to obtain higher voltage gain. Since voltage gain extension is obtained through DCM cells and the turns-ratio of the CI, the voltage stress on the main power switches is only a fraction of the output voltage. Further, the diodes present in each DCM cell need to withstand only a low reverse voltage. To enhance the operating power conversion efficiency, the power switches are turned ON under zero voltage switching (ZVS) condition. Experimental results obtained from a 20V-360V, 200W prototype converter validate the operating principle and the advantageous features of the developed topology.