Common-mode voltage reduction techniques of three-phase Quasi Z-Source Inverter for AC drives

This paper presents the modulation techniques to reduce the common mode voltage (CMV) and common mode current (CMC) in 3-Φ Quasi Z-Source Inverter (q-ZSI) for AC drive systems. A modified Space Vector Pulse Width Modulation technique with reduced number of commutation per sector was used to minimize the CMV and CMC without adding extra circuitry (filters and/or leakage current isolation/bypass circuits) in a q-ZSI whilst maintaining the boost capability of q-ZSI by inserting the shoot-through vector in between the active state vector. Detailed analysis of the modified SVPWM technique to reduce the CMV and CMC of q-ZSI is presented, and performance of the proposed system has been verified using Matlab Simulink.