Salient pole type permanent magnet synchronous motor position sensor-free control method and device

Abstract

The invention discloses a salient pole type permanent magnet synchronous motor position sensor-free control method and device. The method includes the following steps that: when a salient pole type permanent magnet synchronous motor operates in a high-speed operation mode, voltage and phase current at the motor end are acquired and are transformed into voltage and current under an alpha-beta coordinate system, so that a counter electromotive force can be estimated, and therefore, a rotor angular position can be obtained; when the salient pole type permanent magnet synchronous motor operates in a low-speed or zero-speed mode, symmetrical three-phase high-frequency rotating voltage is injected into a stator winding; rotor position information can be obtained through the interaction of the symmetrical three-phase high-frequency rotating voltage and the salient poles of the motor; and the rotor angular position or the rotor position information are substituted into a weighted equation of a linking algorithm, so that current rotor position and speed can be estimated. The control method of the invention is not only suitable for high speed, but also suitable for low speed and zero speed, and can increase the reliability of motor driving.

Description

technical field [0001] The invention relates to the technical field of motors, in particular to a position sensorless control method for a salient pole permanent magnet synchronous motor. Background technique [0002] Since the 1980s, supporting technologies such as modern motor technology, modern power electronics technology, microelectronics technology, control technology and computer technology have developed rapidly, and the development of AC servo control technology has made great progress. more reasonable. Due to the high efficiency, small size and small torque ripple of the permanent magnet synchronous motor, the permanent magnet synchronous motor has become a development trend of the motor servo system. However, synchronous motors usually include mechanical position sensors (encoders, tachogenerators) to implement position-based control algorithms. Such sensors have problems such as installation, cable connection, failure, etc., and affect system reliability and lim...

AI Technical Summary

Problems solved by technology

However, although the implementation of this method based on fundamental wave excitation is simple, it cannot be detected at zero or low speed because the back EMF is too small, so it is only suitable for high-speed operation

In addition, these methods in the related art need to use the fundamental voltage and current signals to calculate the rotor position and speed, resulting in sensitivity to changes in motor parameters and poor robustness

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