中型高压电动机暂态温度场分析及短时过载运行研究

Transient temperature field analysis and short-term overload operation of medium high voltage motor

针对中型高压感应电动机暂态温升难以准确计算的问题,以一台紧凑型中型高压感应电动机为例,采用电机内各物理场间强耦合与弱耦合相结合的多物理场三维动态耦合分析方法,对其暂态温升进行计算。根据电机内定、转子区域流-固耦合的特点,建立电机温度场与流体场的三维强耦合分析模型。利用电机动态数学模型、磁网络模型、集肤效应模型及流体网络模型对电机损耗、转速及入口流量等进行计算,并作为耦合边界条件实现与流-固耦合模型的瞬态弱耦合求解。模拟了电机起动过程中温度的变化过程,验证了研究方法的正确性。对短时工况不同负载条件下电机的温升进行计算,获取负载条件对电机温升的影响规律,为电机的短时过载运行提供依据。研究内容为中型高压电动机暂态温升的计算及保障电机多工况的安全运行提供了参考。

Aiming at the problem that it is difficult to calculate the transient temperature rise of medium high voltage induction motor accurately,taking a compact medium high voltage induction motor as an example,the transient temperature rise of the motor was calculated by using the multi-physical field 3d dynamic coupling analysis method which combines strong coupling and weak coupling among the physical fields in the motor.According to the characteristics of fluid-structure coupling in stator and rotor region of motor,a three-dimensional strong coupling analysis model of temperature field and fluid field of motor was established.The motor loss,speed and inlet flow rate were calculated by using the dynamic mathematical model,magnetic network model,skin effect model and fluid network model,and the transient weak coupling solution with the fluid-solid coupling model was realized as the coupling boundary condition.The temperature change process during the motor starting process was simulated and correctness of the research method was verified.The temperature rise of the motor under different load conditions was calculated,and the influence rule of load conditions on the temperature rise of the motor was obtained,which provides a basis for the short-time overload operation of the motor.This study provides a reference for cal-culating the transient temperature rise of medium high voltage motor and ensuring the safe operation of the motor under multiple working conditions.