Analysis of contact resistance effect between magnet segments on eddy current losses

This paper presents analytical formulations and 3D finite element calculations for the analysis of effects of the contact resistance between two poorly insulated magnet segments regarding eddy current losses. The calculations deal with low speed large direct drive permanent magnet wind turbine generators. The analytical and finite element results are compared for different contact conductivities. The analysis considers the low frequency harmonics of the concentrated stator winding neglecting the eddy current self field.