A Reduced Switching Loss PWM Strategy to Eliminate Common-Mode Voltage in Multilevel Inverters

作者：Nho Van Nguyen^*; Tam Khanh Tu Nguyen; Lee Hong Hee

来源：IEEE Transactions on Power Electronics, 2015, 30(10): 5425-5438.

DOI：10.1109/TPEL.2014.2377152

• Common-mode voltage (CMV)
• multilevel inverter
• pulse width modulation (PWM)
• switching loss

This paper introduces a novel pulse width modulation (PWM) technique to eliminate common-mode voltage in odd-multilevel inverters using the three zero common-mode vectors principles. Similarly, as in conventional PWM for multilevel inverters, this PWM can be properly depicted in an active two-level voltage inverter. With the help of two standardized PWM patterns, the characteristics of the PWM process can be fully explored in that active inverter as a switching time diagram and switching state sequence. Due to an unequal number of commutations of three phases in each sampling period, the switching loss is optimized by a proposed current-based mapping algorithm. The switching loss reduction can be up to 25% compared to the same PWM technique with nonoptimized algorithms. The PWM method has been then generalized as an equipotential PWM control, which is valid to both odd-and even-multilevel inverters. The theoretical analysis is verified by simulation and experimental results.

• 出版日期2015-10