Novel integrated motor design that supports phase and pole changes using multiphase or single-phase inverters

To reduce energy consumption, a novel motor system was proposed using two individual current control technologies involving (1) a multiphase inverter and (2) a single-phase inverter. The multiphase inverter technology comprised two sets of three-phase windings connecting two three-phase inverters. Each set of coils connecting the three-phase inverters formed a rotating field. The two windings allowed the resultant field to generate a rotating field of eight or four poles. In contrast, the single-phase inverter technology connected each coil to a single-phase inverter circuit to control individual current vectors. Motor systems capable of changing their pole and phase operate at higher efficiencies over a wide range of speeds. The single-phase inverter technology additionally reduced torque ripple and vibration by controlling the current of each coil independently. For the multiphase inverter technology, results from both simulation and experimental tests confirmed that the motor is capable of changing the pole and phase during rotation. Experimental test results also confirmed that the single-phase inverter technology reduced iron loss in a motor by 50% during pole change.