This paper describes application of electromagnetic field analysis to the calculation of eddy current loss in the permanent magnets of dynamometers which is used for testing vehicle’s transmission performance. Eddy current loss occurs in permanent magnets due to space harmonics and time harmonics of current, and we confirmed that loss is mainly generated by torque vibrating control harmonic current in stator coils.T hen we carried out thermal analysis using eddy current loss as ah eat source calculated in magnetic field analysis, and estimated temperature distribution of rotor.

Keywords : eddy current, thermal analysis, dynamometer, permanent magnet, space harmonics, time harmonics