Uniform modeling for pole-phase modulation induction motors

A winding distributed function method is employed to propose an uniform model for conventional winding-based pole-phase modulation (PPM) induction machines (IM). Inductance matrices, voltage, flux linkages, mechanical dynamics, and torque equations are deduced. A prototype of both 9-phase with 4 poles and 3-phase with 12 poles is used to validate the built model, which is suitable for operation in 3-phase with 12 poles and 9-phase with 4 poles, separately; it also illustrates effective operation in pole-changing process, where both operating cases coexist. The simulated results verify the proposed model. It provides an effective approach to analyze and control this kind of motors, especially for the transient operation during pole-changing. Double vector control algorithms are developed to control the PPM IM, one for operation with 9-phase, and another for operation with 3-phase, with their different parameters and given rotor flux linkage. Moreover, only four current sensors are required even though there are nine winding currents, and torque share function ensures a constant torque during pole-changing. The simulated results verify the vector control based PPM IM drive.