Hybrid Excitation Synchronous Motor control with a new flux weakening strategy

Permanent magnet synchronous motors (PMSM) have been developed for numerous applications due to their attractive features especially after the development of rare earth permanent magnet materials as NdFeB or SmCo. However, the magnets on the rotor accentuate the thermal constraints and limit the high speed operation. To eliminate these drawbacks, a new Switching Flux Synchronous Motor with Hybrid Excitation (SFSMHE) is developed. With the hybrid excitation (coil and magnet), we have an extra degree of flexibility and hence an improved torque-speed characteristics to meet HEV operating constraints. This paper deals with a new method of a torque control and flux weakening of SFSMHE, for electric/hybrid vehicles traction drive conditions. The principles, control structures, simulation and experimental results are given.