Thermal analysis of water cooled surface mount permanent magnet electric motor for electric vehicle

This paper investigates thermal analysis of water cooled surface mount permanent magnet synchronous motor by two approaches. One is a lumped parameter thermal model which enables quickly to predict temperature rise in the electric machine. The other is 3D finite element method which can precisely calculate the temperature considering the effect of end-winding and housing. In addition, the cooling system design plays an important role, which decides the capacity of heat dissipation. The detailed cooling system design is presented including the calculation of fluid resistance and forced convection coefficient as well as energy consumption of pump. The influences of flow rate and thermal contact on the temperature distribution are studied.