Toward the evaluation of the influence of temperature fluctuations on the durability of the stator winding insulation of asynchronous motors in random mode loading

The influence of the stator winding temperature oscillation on the insulation-aging rate of the asynchronous motors stator winding in random mode loading is discussed. It is shown that under certain parameters of the random mode insulation durability can significantly decrease, wherein the widely used average loss method gives the evaluation of the motor thermal state with a substantial error.