Nonlinear interference control method and control system for permanent magnet linear synchronous motor

Abstract

The invention discloses a nonlinear interference control method and a nonlinear interface control system for a permanent magnet linear synchronous motor (PMLSM). According to the control method, an online estimated compensating voltage value ud of a wavelets neural network (WNN) is added on the basis of up+uf of the conventional composite feedforward proportional differential control, and the sum of up, uf and ud is used as the control voltage U(t) of a stator of the PMLSM, namely the control voltage U(t) is equal to up+uf+ud. The WNN is a three-layer forward network, and ud is the sum of omega1psi1, omega2psi2, ..., omegajpsij, ..., and omegampsim. A learning signal of the WNN is an output value of a proportional differential controller. The control system comprises a digital signal processing controller, a power driving module connected with the stator of the PMLSM, and a rotor displacement sensor arranged on the PMLSM. The WNN is used for effectively compensating interference such as PMLSM thrust fluctuation and frictional force and errors of a fixed parameter model, and tracking accuracy can be improved by more than 2.7 times; and the control system can be implemented by universal hardware, and is convenient to popularize and use.

Description

(1) Technical field [0001] The invention relates to the technical field of intelligent control of permanent magnet synchronous linear motors, in particular to a control method for nonlinear interference of permanent magnet synchronous linear motors, which is estimated by wavelet neural network for the torque fluctuation nonlinear interference peculiar to permanent magnet synchronous linear motors and control system. (2) Background technology [0002] Unlike rotating motors, permanent magnet linear synchronous motors (Permanent Magnet Linear Synchronous Motor, PMLSM) do not require any intermediate conversion mechanism, directly converting electrical energy into mechanical energy, and thus have the advantages of simple structure, high precision, high speed and low maintenance. It has broad application prospects in the fields of robots, semiconductor manufacturing, high-precision CNC machine tools and X-Y drive equipment. However, due to its linear structure and the lack of i...

AI Technical Summary

Problems solved by technology

The control method combining adaptive feedforward control with PID control or PD control, by analyzing the frequency spectrum of the error signal, obtains the main harmonics contained in the thrust fluctuation, and implants a "trojan horse" method in the feedforward compensation to reduce The impact of thrust fluctuations on the system has a good control effect, but when this method uses off-line Fourier analysis of the error signal, only the frequency domain information of the interference can be obtained without any time domain information, so it is still not completely accurate. Realize online estimation and compensation of interference

Images