SiC and Si Hybrid Multilevel Current Source Inverter and its Space Vector Modulation Scheme

Current source inverters (CSI) show their unique advantages such as no shoot-through fault, voltage step-up characteristics, and easier control of the output current. To further improve the efficiency and power density of the CSIs, a SiC (Silicon carbide) and Si (Silicon) hybrid multilevel current-source inverter (MCSI) is proposed in this paper. It consists of a three-phase Si IGBT module and a three-phase SiC MOSFET module. The principles and implementation of the SVM modulation scheme are investigated for the hybrid MCSI, which enables the SiC MOSFET module to operate at high frequency, meanwhile the Si IGBT module at fundamental frequency. The proposed inverter takes full advantage of the low switching loss of SiC MOSFET to realize the superior performance of CSI. Finally, a hybrid MCSI is designed and the effectiveness of the proposed hybrid MCSI is verified with the simulation.