Automotive electric motors, generators, and actuator drive systems with reduced or no permanent magnets and innovative design concepts

The Special Issue of IEEE Transactions on Industrial Electronics, October 2014, discusses papers on electric vehicles (EV) and hybrid EVs (HEV) that are gaining increased attention due to environmental and energy concerns. At the heart of the drive system of these vehicles is the electric machine and drive. For these applications, high power density, high torque density, wide speed range, and efficiency are of primary importance. To meet these demands, interior-permanent-magnet (IPM) machines have been widely used. The motivation for this paper was to address the issue of position sensorless operation at zero or very small current values by increasing the saliency. Finite element analysis and laboratory results are provided to validate the performance of the new design. The paper puts the technology in context by addressing the related aspects of HEVs, such as the power split device and the hybridization index.