Analysis and Improvement of Reliability of Surface-Mounted Permanent Magnet Synchronous Motors Based on Subdivision Subdomain Models

The reliability of permanent magnet synchronous motors (PMSMs) has become a crucial indicator for measuring their comprehensive performance. The existing researches on motor reliability analysis and improvement mainly focus on the study of a single reliability index, and the analysis mainly relies on time-consuming finite element method (FEM). Moreover, considering the global optimization of multiple physical properties of motors is tedious and irreversible demagnetization of permanent magnets (PMs) is often overlooked. In response to the shortcomings of existing researches, a precise analytical method (AM) for multiple reliability indicators of surface-mounted permanent magnet synchronous motors (SPMSMs) based on subdivision subdomain models is innovatively proposed in this paper, the key reliability indicators of SPMSMs, including irreversible demagnetization of PMs, torque ripple, and electromagnetic vibration, are comprehensively predicted, and the rapidity and accuracy of reliability analysis can be balanced. Compared with FEM, the proposed AM reduces the calculation time by about 93.75% while ensuring calculation accuracy. Afterwards, a multi-objective global analytical optimization model that combines particle swarm optimization (PSO) algorithm with proposed precise AM is established, and the optimal structural parameters of eccentric PMs that can effectively improve the reliability of SPMSMs are quickly determined, which provides a fast, accurate, convenient, and universal analysis method for the comprehensive improvement of multi physical properties. Finally, both finite element simulation and prototype testing results have demonstrated the accuracy of the proposed AM and the rationality of the optimization results.