A four-quadrant modulation technique for Cascaded Multilevel Inverters to extend solution range for Selective Harmonic Elimination / Compensation

Abstract

One critical drawback of Selective Harmonic Elimination (SHE) and Compensation (SHC) in CascadedMultilevel Inverter (CMI) topology is that the solution range is very limited and in an irregular shape. As a result, the compensation capacity and system parameters are hard to determine. This paper proposed a voltage phasor diagram to explain the reason of the limited solution range, proposed a fourquadrant modulation method to achieve an enlarged and regular solution range, and discussed guidelines for system parameters design. Simulation and experimental results verified the method's effectiveness.