An inverter-fed self-controlled 'brushless' DC series motor with the field winding in the DC link

The paper examines the basic operation of a self-controlled synchronous motor driven by a 3-phase MOSFET inverter with the field winding located in the DC link yielding series characteristics. A new approach to the analytical and experimental study of the drive with the switches conducting for both 120/spl deg/ and 180/spl deg/ is presented and typical results, both simulation and experimental, are shown and the performance characteristics compared. The effect of shifting the rotor position sensor is also studied in both cases. It is observed that the resulting drive system is simple, able to operate with reduced torque ripple and voltage spikes and the characteristics of the drive are well suited for traction/transit system and battery/flywheel energy storage systems.