Performance analysis of double-stator starter generator for the hybrid electric vehicle

In accordance with the installation characteristics of the starter generator (SG) system in the hybrid electric vehicle (HEV), a design of the flat structure double-stator permanent-magnet (PM) brushless electric machine is presented in this paper. Four feasible structure styles are introduced; the merits and the defects of each structure are analyzed and compared. Electromagnetic field finite-element method (FEM) and experimental research are applied to analyze the effects of the structure parameters on the performance of the double-stator PM brushless electric machine. When it works as a motor, a simulation analysis on the width of the rotor pole arc, the number of magnet poles, the length of the outer and inner air gap that affect the performance of the motor are done. When it works as a generator, the experiment results and the simulation analysis indicate that the existence of the inner stator greatly improves the generating capacity of the SG and solves the difficulty in adjusting the voltage of the PM generator.