Two-Level Multi-Objective Design Optimization Including Torque Ripple Minimization for Stator Excited Synchronous and Flux Switching Machines

Electric machine performance can be enhanced through torque ripple mitigation, which reduces mechanical vibrations and improves system stability and operation. This paper proposes a novel two-level optimization method for synchronous flux-switching and hybrid excitation machines, featuring an innovative multi-point spline shaping approach for torque ripple minimization. The study employs experimentally validated models based on a prototype with a similar topology. The optimization process is implemented on two distinct designs: a 20-pole inner rotor PM-excited stator machine and a 28-pole outer rotor DC-excited stator machine. Analysis results demonstrate that the proposed innovative method significantly reduces torque ripple in both configurations. Force calculations and structural stress analysis confirm the machines’ manufacturability and their capability to operate at rated speeds, validating the effectiveness of the multi-point spline pole shaping method.