Multi-field coupling finite-element analysis of the temperature rise in permanent magnet synchronous motor applied for high speed train

This paper presents the thermal analysis of a permanent magnet synchronous machine (PMSM) which is applied for high speed train. An accurate method to calculate the temperature distribution of the PMSM is proposed here based on 3-D finite element method and multi-field coupling theory. The loss in electromagnetic field and the velocity in the fluid field are figured out separately, and then loaded into the thermal field to obtain the temperature rise of PMSM. So machine behavior in aspects of electromagnetic, thermal, and fluid-dynamic characteristics can be predicted. Furthermore, the relationship between ventilation velocity and temperature distribution is investigated for an air-cooled PMSM. In order to verify the effectiveness of methods proposed in this paper, corresponding experiments are accomplished for a 3-phase 6-pole 600kW, 4200r/min PMSM with 30m3/min ventilation, and the experimental results agree well with the simulation.