Abstract
In this paper, a novel AC motor termed the flux-modulating synchronous machine (FMSM) is presented. The FMSM employs a doubly salient structure, and the armature and field windings are centrally wound around individual stator teeth. The rotor has neither permanent magnets nor windings. A 1.5-kW prototype machine with an outer-rotor configuration is newly designed and built to investigate the characteristics of the FMSM in a motor mode. The torque-generating mechanism is analyzed using a mathematical model of the FMSM, and experiments are conducted with a vector control system to confirm the validity of the theoretical analysis. The results show that the torque of the FMSM can be controlled by adjusting the armature and field currents, as in the DC motors.