Fast modulation strategy for open-end winding PMSM with common DC bus

Abstract

An open-end winding PMSM drive system with a common DC bus can produce zero-sequence current and high switching loss, which reduce the performance and efficiency of the system. Aiming at this problem, this paper proposes a fast modulation strategy that can effectively suppress the zero-sequence current, reduce the number of switching times in a sampling period to 6, and reduce the average switching loss by 50%. In addition, when compared with the conventional CBPWM and SVPWM algorithms, this strategy does not need to decompose the modulation wave, or synthesize the voltage vector. Furthermore, the calculation burden is small, which makes it very easy to implement. Experimental results verify the effectiveness and feasibility of this strategy.