Evaluation of frame-induced compressive stress on the magnetic properties of stator cores using the excitation inner core method

To improve the efficiency of electric motors, we developed the excitation inner core method to evaluate the magnetic properties such as the iron loss of the actual stator core. After preparing two stator cores with a frame, we examined the frames influence of compressive stress by applying the standard and small excitation inner core methods to evaluate the iron loss of both stator cores having a frame. After removing the frames of the two stator cores, we evaluated the iron loss of two stator cores without the frames again by applying both methods.