Single-Phase Chebyshev Algorithm for Harmonics Mitigation in CHB Five-Level Inverters

This paper presents a modulation technique based on a time partition obtained by first kind Chebyshev polynomials zeros suitable for single phase cascaded H-bridge five-level inverters. After a detailed mathematical description of the method, some simulation results and some comparisons among the proposed method, level-shifted and phase-shifted pulse-width modulation techniques are presented and discussed. It can be observed that proposed technique outperforms the above mentioned methods in terms of total harmonic distortion factor.