Evaluation of carrier-based PWM strategies for multi-state switching cells-based multilevel three-phase rectifiers

Rectifiers employing multi-state switching cells concepts are promising alternatives for high power, high power density and high efficiency applications. Multi-state switching cells-based multilevel three-phase PWM rectifiers (MLMSR) require proper modulation strategies to operate. Several modulation strategies are applicable to such rectifiers. However, each modulation strategy leads to a given set of performance indicators. These include differential- (DM) and common-mode (CM) electromagnetic emissions, voltage gain, passive components physical dimensions and power semiconductor efforts. This work introduces the fundamental analysis of a MLMSR. Additionally, three carrier-based modulation patterns are evaluated with respect to the common mode voltage generation, input current ripple, multi-interphase transformer magnetizing current and the current through the dc-link midpoint. Finally, simulation results are presented in order to highlight the characteristics of each modulation strategy for two MLMSR configurations.