Multi Physics Thermal Simulation and Passage Optimization of a Permanent Magnet Synchronous Motor

A new method for multi physics field coupling analysis based on genetic algorithm and applicable to the structural optimization of permanent magnet synchronous motors is proposed in order to solve the problem of existing motor design methods only focusing on a single physical field and low simulation accuracy. Established an electromagnetic field model for a certain permanent magnet synchronous motor operating at the speed of 3000 r/min and the peak driving current of 800 A, and used the simulated electromagnetic losses as boundary conditions for the model. Conducted parameterized 3D model for the permanent magnet synchronous motor, generated simulation input data based on the optimal space filling design, and simulated the fluid field and temperature field. After obtaining the simulation results, response surfaces for three optimization indicators were established, and MISQP algorithm was used to optimize the passage size, obtaining the optimal channel width 38.08 mm and channel height 11.99 mm. The results indicate that the principle of this method is correct and can select the optimal passage size design within the specified range.