Methodology for the volume minimization in non-isolated SiC based PV inverters

The opportunities for both power density and efficiency improvements of photovoltaic (PV) inverter have come with the development of commercially available wide bandgap (WBG) devices such as Gallium Nitride (GaN), and Silicon Carbide (SiC). The focus of this paper is to demonstrate a methodology for achieving a minimum volume of the differential and common mode parts of the output filtering while meeting power quality and electromagnetic interference (EMI) specification and maximizing efficiency. Temperatures are kept constant between both Si and SiC designs. Efficiency improvements are also characterized through an accurate calculation of device and magnetic component losses—the largest contributors to loss in the system. Frequency dependent behavior of filter components are taken into account as well as mitigations for high di/dt and dv/dt. MATLAB/Simulnk and PLECS are used to assist in the process and a 100 kVA PV inverter is considered in this work.