Retrospective of electric machines for EV and HEV traction applications at general motors

This paper presents a retrospective of electric motor developments in General Motors (GM) for electric vehicle (EV), hybrid electric vehicle (HEV), plug-in hybrid electric vehicle (PHEV), and fuel cell electric vehicle (FCEV) production programs. This paper includes i) the progression of electric motor stator and rotor design methodologies that gradually improved motor torque, power, and efficiency performance while mitigating for noise, ii) Heavy rare earth (HRE) mitigation in subsequent design to lower cost and supply uncertainty, iii) Design techniques to lower torque ripple and radial force to mitigate noise and vibration issues. These techniques are elaborated in details with design examples, simulation and test data.