LifeTime Estimation of an Interior Permanent Magnet Synchronous Motor for an Operating Temperature Utilizing a Torque Damage Equation

In this paper, a torque damage equation due to the insulation aging of stator windings is proposed to predict the lifetime of a permanent magnet synchronous motor for operating temperature and use time. An insulation resistance equation for the motor is induced to replicate the winding deterioration of a stator under the given operating condition, and then an influence of insulation aging on torque performance of the motor is analyzed by means of an electromagnetic simulation tool. Based on numerical results, a torque damage equation is deduced to establish the relationship between insulation aging and torque deterioration according to the operating temperature and time of the motor. Finally, it is applied to an interior permanent magnet synchronous motor, and the lifetime limit of the motor is estimated for a certain operating temperature.