Position sensor-free double closed-loop speed regulation control method for brushless DC motor

Abstract

A position sensor-free double closed-loop speed regulation control method for a brushless DC motor comprises the following steps: (1) initializing functional modules and peripherals; (2) opening AD (Analog-Digital) interruption and protection interruption; (3) detecting the start key of the motor, judging whether to start the motor, if yes, executing the next step, and if not, continuing to execute the step; (4) starting voltage detection, judging whether the voltage of a main circuit is larger than starting voltage, if yes, executing the next step, and if not, returning to the step (3); (5) entering a motor starting subprogram and beginning operating the motor; (6) entering a double closed-loop speed regulation subprogram, and regulating the rotational speed and the current of the motor according to voltage value; and (7) detecting a motor brake key, judging whether to press the key, if yes, entering a motor brake subprogram, and if not, returning to the step (3). The method provided by the invention overcomes the defects of larger size, low rotational speed accuracy and the like of the conventional motor controller, can accurately control different rotational speeds of the motor, and can simultaneously realize counter electromotive force zero-cross comparison position sensor-free reversing and Hall position signal reversing.

Description

technical field [0001] The invention relates to a control method of a DC brushless motor. In particular, it relates to a double-closed-loop speed regulation control method for a position sensorless DC brushless motor. Background technique [0002] With the rapid development of my country's industry, brushless DC motors have been widely used in automobiles, tools, industrial control, automation and aerospace, etc. Compared with traditional DC motors, brushless DC motors save mechanical The brush device is replaced by electronic commutation, which has reliable performance, never wears out, and has a low failure rate. The service life is about 6 times higher than that of the brush motor, and it has an incomparable leap in performance compared with the DC motor. It is the most ideal speed regulating motor today. The control system of the new brushless DC motor is a fusion of disciplines involving power electronics, electromechanics, automatic control, and material science. With ...

AI Technical Summary

Problems solved by technology

At present, most of the brushless DC motor speed controllers do not have a wide range of speed regulation, low precision, and large volume. For specific types of motors, traditional brushless DC motors contain Hall position sensors, which are provided to the motor as commutation information. The Hall sensor increases the cost of the motor and the size of the motor. The controller of the new DC brushless motor is developed by using the position sensorless control technology, and the position sensorless control technology is the research hotspot of the brushless motor.

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