A New Shared Flying Capacitor Multilevel Converter for SRM Drives

This paper introduces a new multilevel topology for three-phase switched reluctance motor (SRM) drives. The proposed topology features a shared flying capacitor asymmetric half-bridge (SFC-AHB) three-level structure. Compared to the conventional asymmetric half-bridge (AHB) converter, the proposed converter incorporates two switches, two diodes, and a capacitor-each rated at half of the DC link voltage-allowing the generation of three voltage levels for SRM operation. This capability significantly reduces motor torque ripples. Moreover, the proposed converter exhibits considerably lower total power losses than conventional flying-capacitor multilevel converters due to its simplified circuit topology. Simulation results confirm that the proposed SFC-AHB converter, utilizing only a single capacitor, achieves reduced phase current ripple compared to conventional flying-capacitor asymmetric half-bridge (FC-AHB) multilevel converters. Additionally, it requires fewer semiconductor components and gate drivers, leading to lower costs and reduced system complexity.