Nitinkumar R. Patel

Encoderless IPM traction drive for EV/HEV's

This paper presents an accurate and robust method of estimating rotor position for an IPM drive system for EV/HEV applications. The importance of position sensorless technique for electric propulsion drives has been highlighted in the present study. Stability and dynamic behavior of the position estimation is critical in real world applications. The paper provides experimental results, which demonstrate the excellent performance of the proposed control algorithm. The goal of this paper is to design, implement and successfully demonstrate a sensorless control algorithm for EV/HEV propulsion drive system which works over the entire torque-speed range including zero mechanical speed achieved by combining two rotor position estimation methods for low and high speed ranges.

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.