PV Inverter Systems Enabled by Monolithically Integrated SiC based Four-Quadrant Switch

Ajit Kanale

Funding Source: DOE SETO

Objective: This project aims to design, develop and qualify a cyclo-converter based grid-connected PV inverter enabled by monolithically integrated 4H-SiC four-quadrant-power-switch (4-QPS).

Summary: The project is a novel method to realize a cycloconverter topology using bidirectional switches. It involves detailed analysis, modeling and development of the four-quadrant switch. This device will be incorporated in a 1.5 kW prototype 1-phase grid connected AC converter. Associated efforts will include gate driver design and operation at high frequencies, short circuit protection and ruggedness enhancement, along with features for system diagnostics and closed-loop control of the grid connected converter. The topology will also be expanded to a 15 kW scale for a 3-phase solution.

Impact: The use of monolithically integrated bidirectional switches allows cycloconverter topology implementation WITHOUT DC electrolytic capacitors between stages. The use of these switches can facilitate development of standardized modules and enable a compact and scalable solution for the end-user.