Counter electromotive force detection device of motor and motor

Abstract

The invention discloses a counter electromotive force detection device of a motor and the motor. The device comprises a first detection unit which is configured to detect the U-phase counter electromotive force of the motor as a U-phase detection potential, a second detection unit configured to detect a back electromotive force of a V-phase of the motor as a V-phase detection potential, and a third detection unit configured to detect a back electromotive force of a W-phase of the motor as a W-phase detection potential; the first detection unit can be coupled with the second detection unit and the third detection unit to generate a neutral point potential of the motor as a reference potential so as to determine a commutation moment of the motor based on the reference potential according to the U-phase detection potential, the V-phase detection potential and the W-phase detection potential. According to the scheme, the counter electromotive force detection circuit is arranged, the counter electromotive force of the motor is detected through the counter electromotive force detection circuit, rotor positioning of the motor is achieved according to the counter electromotive force, and the rotor positioning difficulty of the brushless direct current motor is reduced.

Description

technical field [0001] The invention belongs to the technical field of motors, in particular to a back electromotive force detection device and a motor, in particular to a back electromotive force detection circuit and a motor (such as a permanent magnet brushless DC motor). Background technique [0002] The working principle of the brushless DC motor must have information related to the position of the rotor magnetic field to control the switching on or off of the power device in the inverter to realize the commutation of the stator winding. When the brushless DC motor commutates, it is necessary to detect the rotor position information, but the detection of the rotor position information is relatively difficult. [0003] In related solutions, the rotor position information of the brushless DC motor is directly detected by electromechanical or electronic sensors, such as Hall sensors and photoelectric sensors. The structure and control circuit of the square wave brushless...

AI Technical Summary

Problems solved by technology

[0006] The object of the present invention is to provide a back electromotive force detection device and a motor to solve the problem that the rotor positioning of the brushless DC motor is relatively difficult, and to achieve the purpose of detecting the back electromotive force of the motor by setting a back electromotive force detection circuit. Electromotive force, the rotor positioning of the motor is realized according to the counter electromotive force, and the effect of reducing the difficulty of rotor positioning of the brushless DC motor

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