Design of isolated interleaved boost DC-DC converter based on SiC power devices for microinverter applications

Abstract

The power delivered by a photovoltaic (PV) to the grid must be modified in multiple stages. The operation concept of the micro-inverter is to increase the low output voltage received from a PV panel. Wide bandgap (WBG) power devices such as SiC MOSFETs offer multiple advantages over traditional silicon power devices when are used in a solar energy field due to their high switching frequency, high thermal conductivity and high power density that led to high efficiency and a smaller size of a converter. This paper demonstrates the implementation and design of an isolated interleaved boost DC-DC converter using a capacitor voltage doubler to achieve a high voltage step ratio. The performance of the design is analyzed and investigated at high switching frequency using different power switching devices, Si and SiC MOSFETs. The simulation results show that a 3% improvement achieved by SiC MOSFET at a higher switching frequency of 300 kHz.