SHM-PWAM Control Strategy Applied to a Five-Level Flying-Capacitor Inverter

Compared to the conventional selective harmonic mitigation-pulse width modulation (SHM-PWM), the selective harmonic mitigation-pulse width and amplitude modulation (SHM-PWAM) control strategy for multilevel inverters has considerable advantages such as improved output harmonics contents and reduced power dissipation. These are due to the optimization of dc sources values along with the optimized angles. However, realizing the SHM-PWAM needs the regulation of dc sources in different values with acceptable dynamic response. The flying capacitor multilevel inverter (FCMLI) has the ability of the dc voltages self-balancing due to its switching state redundancies so a promising topology for the realization of the SHM-PWAM. In this paper, the SHM-PWAM control strategy is applied to a five-level FC-MLI. Simulation results show the priority of PWAM over the conventional PWM from the total harmonic distortion (THD) improvement and power dissipation reduction points of view.

Keywords:

FCMLI , PAM , PWAM , PWM , THD , Voltage balancing