Electric motor with active hysteresis-based control of winding currents and/or having an efficient stator winding arrangement and/or adjustable air gap

摘要

An electric motor is provided with active hysteresis-based control of winding current. The motor has an efficient stator winding arrangement, as well as at least one adjustable air gap. Also provided is a stator, windings and air gap adjustment mechanism, as well as a method and system for controlling the torque produced by the motor using active hysteresis-based control of the motor's winding currents. The stator has its windings distributed among arc sections, the windings in each arc section being associated with only one phase of the motor. The hysteresis-based control of winding current is active in that a bandwidth or spread of the hysteresis band is adjusted depending on at least one of several selectively determined factors. The motor and its associated components are particularly well-suited for use in an electrically powered vehicle, as well as in hybrid vehicles using both electric power from a battery and electric power derived from a fuel-burning engine. A current detector is provided for generating outputs indicative of current flowing through each of three phase windings in a motor, based on detected magnitudes of current flowing through only two of the phase windings. Also provided is a discharge device for discharging residual voltage on a power bus of an electric vehicle.