A Sensorless Brushless DC Motor Commutation Error Correction Method Based on Neural Network Controller

Abstract

The invention relates to a neutral network controller-based method for correcting the commutation error of a sensor-free brushless direct-current motor. The method comprises the steps of extracting anelectromotive force (EMF) zero-crossing of the motor according to the line voltage difference of the motor and correcting the commutation error by adopting an adaptive neutral network controller. Themethod has high error convergence speed and strong adaptability for parameter perturbation and other influences. The neutral network controller comprises an input layer, a hidden layer and an outputlayer, wherein the input layer is used for receiving the error of phase EMF voltage difference and integral thereof to serve as two input nodes; and weighting factors W1 and W2 are respectively connected between the input layer and the hidden layer and between the hidden layer and the output layer, and the control performance of quickly converging error can be obtained by reasonably selecting thelearning rate of the controller. The stability condition of the closed-ring system can be obtained by analysis of the Lyapunov stability theory.

Description

technical field [0001] The invention relates to the technical field of brushless DC motors, in particular to a sensorless brushless DC motor rotor commutation error correction method based on a neural network controller, which is applicable to the fields of industry, aerospace control, etc., and realizes brushless DC without position sensors The motor is precisely commutated. Background technique [0002] Brushless DC motors are widely used in industry, robot industry, automobile, aerospace and military fields due to their advantages of high power density, high efficiency, high torque inertia ratio, and compact structure. Traditional brushless DC motors require position sensors to provide rotor position information to achieve accurate commutation control. However, the installation of position sensors not only increases equipment costs, but also puts forward higher requirements for the daily maintenance of the motor, and also reduces Overall system stability and reliability....

AI Technical Summary

Problems solved by technology

However, due to the influence of low-pass filtering, armature reaction and device delay, the commutation signal generated by the back EMF zero-crossing detection method will inevitably be accompanied by commutation errors

Although the error can be directly calculated or corrected by a PI controller, however, due to the strong nonlinearity of the motor, it may be affected by the back EMF harmonic coefficient, rotor speed and ambient temperature

If conventional controllers are used, error correction will be less effective in the presence of motor parameter disturbances

Images