This paper proposes accurate analytical formula for common mode voltage (CMV) and total current harmonic distortion (ITHD) in the frequency domain, which is universal for all switching angles and modulation ratios. Then, combined with three-level optimized pulse patterns (OPPs), a specific implementation algorithm is proposed to calculate the optimal switching angle sequence with the minimum ITHD under zero CMV. Based on this, the linear relationship of switching angles is explored, and an empirical formula for the linear relationship within different modulation ratio ranges is proposed, thereby simplifying three-level OPPs algorithm for zero CMV and improving its efficiency. Finally, the simulation results achieve zero CMV and verify the reduction of ITHD through some comparisons, which prove the accuracy and effectiveness of the proposed algorithm.

optimized pulse patterns (OPPs),common mode voltage (CMV),multilevel converter,total current harmonic distortion (ITHD)