An optimal zero‐sequence voltage injection‐based common‐mode voltage reduction pulse‐width modulation for the reduction of common‐mode voltages in both amplitude and third‐order component

Abstract

Abstract An optimal zero‐sequence voltage injection‐based common‐mode voltage reduction pulse‐width modulation (CMVRPWM) for the reduction of common‐mode voltages (CMVs) in both amplitude and third‐order component is proposed in this paper. On the basis of general symmetrical switching patterns of CMVRPWM, a constrained mathematical programming model is established with the objective of optimizing the volt‐second value of CMV in each switching period. By solving the mathematical model, the limitation of the CMV amplitude and the reduction of third‐order harmonic in CMV can be achieved simultaneously, contributing to better CMV suppression and common‐mode filter design in the applications of two‐level voltage source inverters (2L‐VSIs). The optimal zero‐sequence voltage under the given target is obtained, and the calculation method of the switching pattern and modulation wave is studied. Simulation and experimental results show that the proposed method can restrict the CMV amplitude within one‐sixth of the DC bus voltage, and the third‐order component in CMV is effectively reduced compared with the conventional methods.