Vector control and experimental verification of magnetically modulated motor for HEV application

Vector control of a magnetically modulated motor (MMM) is described in this paper. The structure of the motor is rather different from a standard permanent magnet synchronous motor (PMSM) because it has two rotors with two different mechanical output shafts, i.e., an outer magnetic-flux modulator and an inner PM rotor. There have been several studies on an electromagnetic field analysis and an optimum design of the motor, but investigation on the vector control using a real machine is still unexplored. Therefore, the paper discusses the vector control algorithm of the MMM and experimentally examines control performance of the mechanical output power delivered by the two rotors, using a prototype machine. Several experimental tests have been conducted under some driving modes, assuming a hybrid electric vehicle (HEV) application. It has been verified that the control algorithm discussed in the paper makes it possible to control the two rotor output power as well as the stator input power like a conventional planetary-gear-based HEV, including the motoring and regenerating modes.