Research on current tails of non-conducting winding in doubly salient permanent magnet motor

For a 9kW, 12/8-pole flume-rotor doubly salient permanent magnet motor, working principles of its three-phase full-bridge inverter is first analyzed, with the single-chop control strategy. Then the theoretical analysis of non-conducting winding during every working region is given, which reveals that non-conducting winding that should have no current for every working region appears current tail. The appearance time, disappearance time and the value for current tails are deduced, and the influence of current tails on motor performance is illustrated. The influences of input voltage, back EMF, and load on current tails are analyzed when hall sensor positions are adjusted accurately or not accurately, with certification of experimental results. Finally, some conclusions are drawn.