Thermal modelling of switched flux permanent magnet machines

This paper presents the electromagnetic loss and thermal modelling of a switched flux permanent magnet (SFPM) machine. A 2D finite element method is first used to calculate the stator and rotor iron losses as well as PM eddy current losses. Then, 3-D thermal modelling has been performed for analysing the temperature distribution within the SFPM machine, the calculated power losses have been applied to different machine components as heat sources to predict the temperature distributions throughout the SFPM machine. A prototype of 50 kW SFPM machine has been used for thermal tests under both open-circuit and on-load conditions. Good agreement between measured and simulated results has been achieved.