Operation Enhancement of Permanent Magnet Excited Motors with Advanced Rotor Cooling System

Heat dissipation determines the power density of electric motor drives. This paper discusses the influence of different rotor and stator cooling approaches to extend the operational limits of permanent magnet synchronous motors for automotive application. A thermal lumped parameter model as well as an electromagnetic finite element model of the traction drive are employed. The thermal model is parameterized utilizing test bench measurements. The enhancement of advanced cooling approaches on operational limits is compared i.e. application of phase change material., heat pipes., air gap cooling., direct lamination cooling., shaft cooling and direct winding head cooling.