A system includes a motor having a plurality of windings, a rotor and a stator magnetically coupled to the rotor, a plurality of power inverters connected to respective windings, wherein the plurality of power inverters is configured to control currents of the plurality of windings, and a controller configured to determine an injection ratio of a high-order harmonic component to a fundamental component based on a performance index, and wherein the injection ratio for a magnetizing component is different from the injection ratio for a torque component at a same harmonic frequency.

An electrical system includes a multi-level traction power inverter module (TPIM), a polyphase electric machine, and a controller. The TPIM has multiple switching sets collectively operable for inverting a DC voltage on a DC voltage bus into an AC voltage on an AC voltage bus. The electric machine has (m) multiple electrical phases. Each of the (m) multiple electrical phases is connected to and driven by a respective one of the switching sets of the TPIM. The controller determines when the electric machine enters a predetermined partial-load region of operation, and, responsive to entry into the predetermined partial-load region, selectively deactivates a predetermined number (n) of the (m) multiple electrical phases. This is done via switching state signals to corresponding ones of the switching sets, with nm2.

A method includes adjusting currents of a plurality of windings of a motor through a plurality of power converters coupled to the plurality of windings so that the number of poles and the number of phases of the motor are dynamically adjustable, and injecting a plurality of high-order harmonic currents into the plurality of windings of the motor through controlling the plurality of power converters to improve a performance index of the motor.

A method includes adjusting currents of a plurality of windings of a motor through a plurality of power converters coupled to the plurality of windings so that the number of poles and the number of phases of the motor are dynamically adjustable, and injecting a plurality of high-order harmonic currents into the plurality of windings of the motor through controlling the plurality of power converters to improve a performance index of the motor.

A motor device includes a stator unit including a plurality of first slots, a rotor unit rotatable relative to the stator unit, a winding unit, and a transfer switch unit. The winding unit includes first and second windings installed in the first slots. Number of poles of the first winding is less than that of the second winding. The transfer switch unit is electrically connected to the first and second windings, and is controlled to allocate access to electricity to each of the first and second windings.

A motor device includes a stator unit including a plurality of first slots, a rotor unit rotatable relative to the stator unit, a winding unit, and a transfer switch unit. The winding unit includes first and second windings installed in the first slots. Number of poles of the first winding is less than that of the second winding. The transfer switch unit is electrically connected to the first and second windings, and is controlled to allocate access to electricity to each of the first and second windings.

A control apparatus is provided to control a rotating electric machine whose number of poles is switched from a pre-switching number of poles to a post-switching number of poles. The control apparatus includes a pre-switching control unit, a post-switching control unit and a transition control unit. The pre-switching control unit controls the torque generated by the machine before the switching of the number of poles. The post-switching control unit controls the torque generated by the machine after the switching. During a pole-number switching period, the transition control unit controls electric currents flowing in stator coils of the machine or voltages applied to the stator coils to make each magnetic pole formed with control by the pre-switching control unit not coincident with any magnetic pole formed with control by the post-switching control unit and having the same polarity as the magnetic pole formed with the control by the pre-switching control unit.

A control apparatus is provided to control a rotating electric machine whose number of poles is switched from a pre-switching number of poles to a post-switching number of poles. The control apparatus includes a pre-switching control unit, a post-switching control unit and a transition control unit. The pre-switching control unit controls the torque generated by the machine before the switching of the number of poles. The post-switching control unit controls the torque generated by the machine after the switching. During a pole-number switching period, the transition control unit controls electric currents flowing in stator coils of the machine or voltages applied to the stator coils to make each magnetic pole formed with control by the pre-switching control unit not coincident with any magnetic pole formed with control by the post-switching control unit and having the same polarity as the magnetic pole formed with the control by the pre-switching control unit.

The present invention relates to an electronic pole changing-based induction motor control system and a control method thereof. Such induction motor control system comprises an induction motor, an inverter and a DC power supply. The inverter is connected with the motor and the DC power supply respectively, for converting a direct current supplied by the DC power supply to an alternating current supplied to the motor. The motor comprises N three-phase windings (11, 12; 31, 32). The inverter comprises N inversion driving units (21, 22; 41, 42) and at least one control unit. Each inversion driving unit is connected with one three-phase winding. The control unit controls the inversion driving unit to generate a current of the three-phase winding connected thereto, and frequency, amplitude and phase of the current can be controlled by the control unit. The control unit alters current directions or phase angles of at least part of the three-phase windings according to a synchronous rotational speed of the motor, making N three-phase windings form at least two pole-pair numbers. The induction motor control system enhances the low-speed torque and broadens the speed governing operation range, thereby enhancing the control accuracy and operation efficiency, and simplifying a peripheral transmission mechanism.

The present invention relates to an electronic pole changing-based induction motor control system and a control method thereof. Such induction motor control system comprises an induction motor, an inverter and a DC power supply. The inverter is connected with the motor and the DC power supply respectively, for converting a direct current supplied by the DC power supply to an alternating current supplied to the motor. The motor comprises N three-phase windings (11, 12; 31, 32). The inverter comprises N inversion driving units (21, 22; 41, 42) and at least one control unit. Each inversion driving unit is connected with one three-phase winding. The control unit controls the inversion driving unit to generate a current of the three-phase winding connected thereto, and frequency, amplitude and phase of the current can be controlled by the control unit. The control unit alters current directions or phase angles of at least part of the three-phase windings according to a synchronous rotational speed of the motor, making N three-phase windings form at least two pole-pair numbers. The induction motor control system enhances the low-speed torque and broadens the speed governing operation range, thereby enhancing the control accuracy and operation efficiency, and simplifying a peripheral transmission mechanism.