立式鼠笼异步电动机三维CFD热计算

3D CFD thermal calculation for a vertical asynchronous motor with a squirrel-cage rotor

用来拖动动力设备(如核电设备)的立式鼠笼异步感应电动机,其温升不仅影响电机寿命及其安全性,还影响系统能否正常运行,因而,探究其内部的热流场分布特点,进行完善的热设计非常重要。首先建立三维电动机物理模型,然后基于有限体积法进行电机内部空气湍流流动及传热耦合数值模拟,得到空气三维速度、转子铜条与定子绕组等三维温度分布特征。结果表明:对于额定转速为4000 r/min的立式电机,气隙中空气速度显著大于定子风沟齿部、轭部的速度;沿高度方向,转子铜条温升很小,定子绕组及绝缘、每段定子铁心叠片中的齿部与轭部均为靠近风沟位置处温度低,而靠近铁心段中间位置温度高。模拟结果与实验测量数值误差较小,结果较准,确为同类型立式鼠笼异步电机通风设计提供理论参考。

The vertical squirrel-cage asynchronous induction motor is used to drive power equipment,such as nuclear equipment.Its temperature rise affects motor life and safety,and the normal operation of power system.Therefore,it is necessary to explore the characteristics of the internal thermal and flow field and improve the thermal design.Firstly,a 3D physical model of the motor was established.Then the coupled numerical simulation of the turbulent air flow and heat transfer in the motor was carried out based on the finite volume method,and the characteristics of air three-dimensional velocity and temperature of the rotor copper bar,and the stator wingding were obtained.The results show that the air velocity in the air gap is significantly higher than that in the stator wind ducts of tooth and yoke for the vertical motor with rated rotation speed of 4000 r/min.Along the height of half the shaft,the temperature rise of the rotor copper strip is very small,the temperature of the stator windings,insulation and the teeth and yoke in each stator core lamination is higher at the middle section of the core segment than that at each wind duct position.The error between the data of simulation and experimental measurements is relatively small,and the results are accurate.The results can provide a theoretical reference for ventilation design of the same type vertical squirrel cage asynchronous motor.