Method for controlling operation of non-radial displacement sensor of bearingless permanent magnetic synchronous motor

Abstract

The invention discloses a method for controlling the operation of a non-radial displacement sensor of a bearingless permanent magnetic synchronous motor. According to the method, firstly, a nonlinear mathematical model between radial displacement of a rotor and currents of a torque winding, voltage of a suspension winding, currents of the suspension winding and an angle of the rotor; then a multi-core least squares support vector machine is built by the adoption of linear combination of a polynomial kernel function, an index kernel function and a radial base kernel function; preprocessing and normalization are carried out on collected input data and collected output data, the multi-core least squares support vector machine is trained and adjusted, and a weight coefficient and a threshold value of the support vector machine are determined; a radial displacement prediction module of the multi-core least squares support vector machine is connected to the bearingless permanent magnetic synchronous motor in series; a displacement controller is designed, and the non-radial displacement sensor of the bearingless permanent magnetic synchronous motor can be controlled. A mechanical displacement sensor and an interface circuit of the mechanical displacement sensor of a prior system are removed, cost of the system is lowered, high-speed and ultra high-speed operation performance of the system is improved, and high adaptability, robustness and fault tolerance are achieved.

Description

technical field [0001] The invention relates to an operation control method for a bearingless permanent magnet synchronous motor without a radial displacement sensor based on a multi-core least squares support vector machine, which is suitable for high-performance control of the bearingless permanent magnet synchronous motor and belongs to the technical field of electric drive control equipment. Background technique [0002] The bearingless permanent magnet synchronous motor stacks the magnetic levitation control winding that generates radial force and the stator torque winding of the permanent magnet synchronous motor. By controlling the current of the torque winding and the levitation winding, the motor rotation and the stable levitation of the rotor are realized at the same time. Bearingless permanent magnet synchronous motors have the characteristics of no lubrication, no wear, no mechanical noise, etc., and can be used in biochemical and medical fields such as vacuum tec...

AI Technical Summary

Problems solved by technology

[0005] The current non-radial displacement sensor technology of bearingless permanent magnet synchronous motor mainly adopts the high-frequency excitation signal injection method, which uses the motor torque to control the mutual inductance of the winding and the suspension winding, or the relationship between the self-inductance and displacement of the suspension winding, and detects the relationship between the two ends of the suspension winding. Differential voltage is used to estimate radial displacement. This method has defects such as high-frequency signal extraction and complicated signal filtering process.

Due to the continuous injection of high-frequency voltage signals of a certain amplitude, it will have a certain impact on the fundamental voltage

The second is to use the observer method to estimate the radial displacement of the rotor. This type of method needs to establish an accurate mathematical model, but the bearingless motor itself is a complex system that is difficult to accurately model. At the same time, in the actual operation of the motor, there are parameter perturbations, Unmodeled dynamics such as sudden load changes and magnetic saturation and iron loss, these uncertain factors will cause model mismatch

Therefore, this method has defects such as low estimation accuracy, sensitivity to motor parameter changes, and poor robustness.

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