Carrier phase-shifted discontinuous PWM algorithm for cascaded H-bridge inverters

Previous work has shown many general space vector PWM algorithms for cascaded H-bridge inverters. To keep the load balance of switches for cascaded H-bridge inverters, complex pulse cycle control must be added to the algorithms. This paper presents carrier phase-shifted discontinuous PWM (CPS-DPWM) algorithm which can keep load balance of switches automatically. More importantly, switching frequency is reduced up to 2/3 of the previous. Simulation results are given for the verification of CPS-DPWM algorithm.