Discontinuous Space Vector Modulation Strategy for Three-Phase Series-End Winding PMSM

The concept of multiplexing power legs makes series-end winding permanent magnet synchronous machines (SEW-PMSMs) has the merits of high DC-link voltage utilization, low volume, and high efficiency. However, the increased leg current of multiplexing power legs inevitably leads to high power loss of converter. Besides, the multiplexing power legs also have large weight in the common-mode voltage from machine sides, which leads to large amplitude anddv/dtstress of common-mode voltage, compared with non-multiplexing ones. Therefore, although multiplexing power legs bring apparent superiorities to SEW-PMSM, they lead to several impairments as well. Consequently, an optimized discontinuous space vector modulation (ODSVM) strategy is proposed in this paper, where the switching action reduction focuses on the multiplexing power legs to reduce the power loss and amplitude of common-mode voltage caused by the above legs. Moreover, a spatial near state SVM (NSSVM) scheme is proposed to reduce the common-mode voltage from converter/machine sides. Two proposed DSVM strategies are verified and compared with traditional continuous SVM (CSVM) and three existing DSVM methods by experimental results. The effective common-mode voltage and/or power loss reduction are verified experimentally in the proposed DSVM strategies.