A control device and method for reducing commutation torque ripple of brushless DC motor

Abstract

The invention relates to a control device and method for reducing the commutation torque ripple of a brushless direct-current motor and belongs to the permanent magnet motor control field. According to the control device and method of the invention, phase current of the stator of the brushless direct-current motor and the output signals of a Hall sensor are detected, so that an advance angle calculation module is built; and the advance commutation angle of the brushless direct-current motor is adjusted in real time under different rotation speeds and load states, so that the intersection time point of turning on phase current and turning off phase current in commutation can be consistent with the intersection time point of corresponding counter electromotive forces, and therefore, the commutation torque ripple can be decreased. The control device and method of the invention do not rely on motor parameters, do not require complex formula calculation and can effectively reduce the commutation torque ripple.

Description

technical field [0001] The invention relates to an advance angle control strategy and a realization method of a brushless DC motor, belonging to the field of permanent magnet motor control. Background technique [0002] Brushless DC motors have the advantages of high power density, high torque-to-current ratio, and simple structure. In recent years, with the improvement of the performance of permanent magnets, brushless DC motors have been more and more widely used in industrial production. [0003] The ideal back EMF waveform of the brushless DC motor is a trapezoidal wave, which is controlled by a 120° conduction mode, and a constant torque can be generated when a square wave current is passed. But in reality, due to the existence of winding inductance, it takes a certain amount of time for the current to rise and fall, and the current value cannot quickly drop from the steady-state value to 0 or rise from 0 to the steady-state value, which will lead to an obvious problem ...

AI Technical Summary

Problems solved by technology

[0011] The purpose of the present invention is to solve the problem in the prior art that the torque ripple cannot be eliminated by controlling the current slope of the on-phase and off-phase to be consistent, and to provide a method for reducing the commutation torque ripple of the brushless DC motor through the advance angle control Control device and method

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