Brushless synchronous machines with wound-field excitation using SMC core designed for HEV drives

This paper presents drive performance possibilities of two types of brushless synchronous machine with wound-field excitation using SMC core for HEV applications. Both proposed machines have no brush or slip ring, but one uses a small amount of rare-earth magnet, it is called as hybrid excitation motor (HEM). The other has no magnet and employs only wound-field excitation. The structures and the basic working principles for both machines are overviewed. The design target is the motor with maximum power more than 123 kW and maximum power density more than 3.5 kW/kg. The performance analyses of the designed machines based on 3D-FEA show that both machines almost meet the target requirements. Some comparisons of the motor performances between both machines is provided. Finally, for HEM, some experimental results using a test machine are demonstrated.