Multi-Objective Parameter Optimization of Permanent Magnet Synchronous Motors

CHENG Lin; JIA Huixing; XU Ming; HU Bin

Abstract：This paper proposes a multi-objective performance optimization scheme for a self-designed permanent magnet synchronous motor(PMSM)with a view to addressing issues of large cogging torque ripple and poor back EMF waveform.The thickness of magnetic steel,the height of the V-shaped structure in the magnetic slot,the pole arc angle of the magnetic slot,and the length of the magnetic steel were selected as the parameters for optimization in order to construct a four-factor optimization design scheme.The scheme employs the orthogonal experiment method,combined with MATLAB software,Maxwell post-processing tools,and motor performance scatter plots,to determine the optimal parameter combination.The analysis encompassed efficiency,load kinetic energy,losses,and no-load characteristics.In both low-speed and high-speed conditions,the motor exhibited a substantial enhancement in output torque,a reduction in iron and copper losses,and effective heat dissipation,thereby ensuring prolonged operational stability.In both low-speed and high-speed peak conditions,while there was an increase in windage,iron,and copper losses,the motor was still able to meet short-term operational requirements through the implementation of water-cooling measures.A comparative analysis of motor performance before and after optimization revealed that the optimized motor achieved an efficiency of over 93.5％within a speed range of 3 000～7 000 r/min,representing a 3.3％ increase in peak efficiency compared to the pre-optimized design.Furthermore,the motors maximum output power exceeded 55 kW within the same speed range,representing a 3.5％improvement over the original design.