Operation and Modulation of H7 Current-Source Inverter with Hybrid SiC and Si Semiconductor Switches

This paper proposes an H7 current source inverter (CSI) consisting of a single shunt-connected silicon carbide (SiC) switch and a traditional silicon H6 CSI circuitry, which could employ the superior characteristics of SiC switch to significantly increase the whole switching frequency with expected low losses simultaneously. In order to reduce the switching counts and also realize the zero-current switching (ZCS) ability for rear-end CSI circuitry, two kinds of H7 CSI modulation schemes have been proposed with either superior output performance or minimal switching counts. Consequently, the proposed H7 CSI can perform as an all-SiC-switch circuitry, and guarantee high performance and high efficiency with a reduced dc inductance. It could be a cost-effective solution to address the efficiency issue of CSIs. MATLAB simulations and experimental verifications have been presented in order to show the performance of the proposed inverter.