Method for detecting position of rotor of permanent magnet motor

Abstract

The invention provides a method for detecting the position of a rotor based on counter potentials of a permanent magnet motor, aiming at overcoming the defects that the traditional methods for detecting the position of the rotor are complex and depend on motor parameters. The method is characterized by after filtering alpha axis counter potential and beta axis counter potential in an alpha-beta coordinate system of the permanent magnet motor, calculating the position of the rotor after phase shifting, and obtaining the actual position of the rotor according to the influence of the predetermined filtering frequency and the predetermined number of filtering times on the phase of the rotor. The method has the following beneficial effects: various spurious signals in the counter potential calculation results can be effectively eliminated to remain the actual signals, thus the estimated position of the rotor is more accurate and stable; and the estimated position of the rotor dispenses with additional check or correction under the condition that the important motor parameters are obviously changed or the range of the motor parameters can be only roughly determined, thus greatly improving the robustness of an observer and being convenient for engineering application and implementation.

Description

technical field [0001] The invention relates to the technical field of motor control, in particular to a method for detecting the rotor position of a permanent magnet motor. Background technique [0002] The permanent magnet motor needs to detect the position of the rotor to realize the commutation of the winding during operation. This is the basis for controlling the permanent magnet motor. The accuracy of the rotor position detection of the permanent magnet motor directly affects the control effect of the permanent magnet motor. Due to the high failure rate of the rotor position sensor, which will reduce the reliability of the entire system, the detection of the permanent magnet motor rotor position has transitioned from sensor detection to sensorless estimation. [0003] In the prior art, in the control method of position sensorless permanent magnet motor, many methods have been proposed to estimate the position and speed of the motor rotor, for example: [0004] 1. ...

AI Technical Summary

Problems solved by technology

[0006] 3. Kalman filter method, the algorithm is complex and the parameters are difficult to adjust;

[0007] 4. Neural network method; the estimation method is relatively complicated, which makes the adjustment of the structure and the design of the parameters more difficult

[0008] In short, the above methods either rely heavily on the motor parameters, and once the motor parameters change greatly (such as air-conditioning compressors, etc.), it will cause a large error in the estimation of the rotor position; or the algorithm is complicated, and the parameter adjustment is complicated and difficult. Very susceptible to external conditions, poor adaptability

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