Research on the Transient Temperature Field of the High-Speed Permanent-Magnet Motor for Dragging Pulsed Alternator

For dragging the pulsed alternator, the high-speed permanent-magnet synchronous motor (HSPMSM) is required with a high-power density. Considering the specific working condition that the speed and load both change with time, the steady-state thermal analysis is not applicable to check the effectiveness of thermal design for the dragging motor. This paper studies the characteristics of the losses of a 300 kW, 12000 rpm dragging motor with the variation of time. Then based on the fluid-solid coupling analysis method, the transient temperature field analysis was then carried out. The variation of temperature field distribution over the time and the influence of discharging times are both discussed. With the pulsed alternator discharging 20 bursts continuously, that is 60 shorts, the temperature rise of the dragging motor is 60.9% of that of the steady-state with the highest speed and maximum power. This paper lays the foundation for the later design and optimization of the dragging motor.