基于流固耦合的高速永磁电机多物理场仿真分析

Multiphysics Simulation Analysis of High-speed Permanent Magnet Motor Based on Fluid-structure Coupling

针对大功率高速永磁电机高频率、高谐波导致其转子温升过高的问题,设计了一种自扇冷、水冷混合冷却散热结构。利用高速旋转的扇叶加速电机内部空气流动,加快电机与外界的热交换,建立流体和固体的耦合接触面,通过流固耦合法计算流体和电机的传热耦合问题。采用有限元法仿真电机额定状态下的电磁场,得出电机损耗以及热源分布,在此基础上分析电机在额定转速下的流体变化情况以及电机温升分布情况。仿真分析表明,自扇冷结构合理的改善了流体散热路径,有效降低了转子永磁体温升。

Aiming at the problem that the high frequency and high harmonics of high-power high-speed permanent magnet motors cause excessive temperature rise of the rotor,a self-fan cooling and water cooling hybrid cooling heat dissipation structure was designed.The high-speed rotating fan blades were used to accelerate the air flow inside the motor,accelerate the heat exchange between the motor and the outside,and establish the coupling contact surface between the fluid and the solid.The fluid-solid coupling method was used to calculate the heat transfer coupling problem between the fluid and the motor.The finite element method was used to simulate the electromagnetic field of the motor under the rated state,and the motor loss and heat source distribution were obtained.On this basis,the fluid change of the motor at the rated speed and the temperature rise distribution of the motor were analyzed.The simulation analysis shows that the self-fan cooling structure reasonably improves the fluid heat dissipation path and effectively reduces the temperature rise of the rotor.