Wound Rotor Salient Pole Synchronous Machine Drive for Traction Application

A drive based on a Wound Rotor Synchronous Machine (WR-SM) is proposed as traction system of electric vehicles. The main features of the proposed drive system are the capability to generate high torque at very low speed without excessive overload of the stator windings and to operate theoretically at constant power until unlimited speed. The analysis of the control strategy, performed using a space vector approach in the d-q plane, has been firstly developed by means of a linear model of the machine and then it has been extended to non linear operating conditions. The effectiveness of the proposed drive system has been verified by experimental tests.