Study on the suppression of CT and TR of IRSP PMSWT based on structural improvement and hierarchical collaborative optimization

To reduce the cogging torque (CT) and torque ripple (TR) of permanent magnet synchronous wind turbine (PMSWT) while ensuring the optimal overall performance of the generator, this paper proposes three improved structures and establishes a "parameter stratification-coordinated optimization" strategy based on the inner rotor salient pole permanent magnet synchronous wind turbine (IRSP-PMSWT). First, the electromagnetic characteristics of the three improved structures are analysed via finite element simulation, and the improved type B with the optimal comprehensive performance is screened out. Second, based on Spearman correlation analysis, the design parameters of type B are divided into two layers according to their degree of influence on the target performance: the first-layer key parameters are optimized for multiple objectives using the improved multi-objective slap swarm algorithm; the second-layer secondary parameters are subjected to single-objective refined optimization using the parameter sweep method. Simulation verification demonstrates that, compared with the traditional structure, the optimized type B achieves a reduction of 15.07% in TR and 55.71% in CT, an increase in torque density, and a reduction in the harmonic distortion rate of no-load back electromotive force (EMF). This realizes the coordinated optimization objectives of low disturbance, high utilization rate, and high density.