Design Optimization of a Harmonic-Excited Synchronous Machine Using the Nelder–Mead Algorithm With an Internal Optimization Procedure

Harmonic excitation synchronous machines (HESMs) with brushless rotor excitation are promising for a range of applications, especially for electric vehicles, due to their compact and reliable design free from slip rings and additional exciters. However, the computer-based optimization of HESMs remains a challenging task, with effective approaches still being actively researched. This article proposes an efficient method for optimizing HESM parameters that accounts for pulse-width modulation effects, utilizing a reduced-order model and a tailored Nelder-Mead algorithm with an integrated internal optimization procedure. The proposed algorithmic enhancements significantly reduced the number of iterations required for convergence and improved key machine characteristics, namely lower losses and reduced current consumption.