Electronic pole changing-based induction motor control system and control method thereof

Abstract

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.

Dependencies are inferred from the claim text.