Novel equipment for the measurement of core losses in laminations for advanced machines

This paper presents a novel state of the art equipment for core loss measurements under high frequency and non-sinusoidal excitations. Sinusoidal high frequency measurements are performed using a commercial test system especially designed for high frequency testing. Comparative measurements are performed over a wide range of frequencies using the three standardized testers; Epstein frame, toroid tester and single sheet tester. Discrepancies in the results obtained from the three testers are shown and analyzed. A test bench is also developed to carry out core loss measurements under non-sinusoidal excitations. Specific core losses at different parts of a permanent magnet motor are predicted by generating the motor flux waveforms in motor laminations using the Epstein frame. The results show a significant increase in the specific core loss in the stator tooth of the machine.