High-Frequency Common-Mode Voltage Reduced Space Vector Modulation for Grid-Connected Current-Source Inverter

Abstract

Suitable space vector modulation (SVM) with reduced high-frequency common-mode voltages (HF-CMVs) for grid-connected current-source inverters (CSIs) have not been well investigated yet. In this study, the potential of active zero-state SVM (AZS-SVM) to suppress high frequency common-mode voltages (HF-CMVs) is revealed and theoretically analyzed, which is different from existing approaches of modifying topology. A special five-segment sequence with an optimally selected third active space vector for AZS-SVM is proposed and applied for CSIs. Simulation and experiments were completed on a (2.5 kW/208 V/6.94 A) grid-connected three-phase CSI. The results indicate that the proposed AZS-SVM mitigates HF-CMVs around unity and double control frequency by a factor of at least four times in contrast to that by conventional SVM, which validates the effectiveness of the proposed AZS-SVM to mitigate HF-CMVs generated by a grid-connected CSI.