Rotor position detection method of brushless DC motor based on single-phase inductance detection

Abstract

The invention relates to a brushless direct current motor rotor position detection method based on single-phase inductance detection. The brushless direct current motor rotor position detection methodincludes the following steps that a detection vector with the time duration being delta T1 is applied to a motor stator winding, the detection phase current is sampled at the beginning and end of vector application correspondingly, and the current change rate is obtained through subtraction of two values; a driving vector with the time duration being delta T2 is applied to the motor stator winding to drive a motor to run; induction energy is released slowly and the motor driving current is maintained by applying a circulation follow current vector in the remaining time of the control period;the variation trend of frac{d}{d<t>} is judged; and the execution steps are repeated continuously after a motor rotor passes through a switching point, and the motor rotor is switched to the next section after waiting for a delay at an electrical angle of 30 degrees.

Description

technical field [0001] The invention belongs to the technical field of motor control, and in particular relates to a method for detecting the rotor position of a brushless DC motor. Background technique [0002] Brushless DC motors have been widely used because of their simple structure, high operating efficiency, and convenient maintenance. Traditional brushless DC motors generally use three-phase six-state two-two conduction mode for drive control, and the rotor position sensor is required to detect six rotor position signals in one electrical cycle in order to commutate the windings. However, the installation of the rotor position sensor increases the size and cost of the motor, and the sensor signal is susceptible to environmental electromagnetic signal interference, which reduces the reliability of the system. Therefore, the research on sensorless rotor position detection technology has important theoretical research significance and application value. [0003] At pres...

AI Technical Summary

Problems solved by technology

The rotor position detection method based on the inductance method needs to inject the detection vector pulse, and the detection vector often has no driving effect or the driving effect is very poor, resulting in relatively poor performance of the motor speed and torque using this method; and the addition of the detection vector is prolonged. The control cycle is shortened, so that the detection accuracy will decrease with the increase of the motor speed

Images