Linear Motor Control Method And Experimental Research Based On PID

High-speed and high-precision motion platform is widely applied in high-endmanufacturing equipment, such as high-end CNC machining center, aerospacemanufacturing equipment, IC packaging equipment etc. With the development ofscience and technology comes higher requirements for high-end manufacturingequipment, which brings a greart challenge of the design for the high-speed andhigh-precision platform and its servo controller. Therefore, this thesis researched thehigh-speed and high-precision linear motor drive technology and its servo controlalgorithm for high-end manufacturing equipment, which is of important theoretical andpractical value to accelerate the development of high-end equipment manufacturingindustry of China.The system error compensation of the linear motor CNC system experimentalplatform was achieved in this thesis.This thesis focuses on the linear motor controlmethods based on PID. Feedforward Fuzzy PID control method was put forward, thesuperiority of which was successfully verified by doing experiments on the linear motorCNC system experimental platform. The main contents and results of this thesis are asfollows:(1) The structures and characteristics of high-speed precision platform driven bylinear motor were grasped, and the mathematical model of permanent magnetsynchronous linear motor was established. At the same time, the system error of linearmotor CNC system experimental platform caused by manufacturing and assemble wascompensated by using the piecewise linear error compensation model.(2) The feedforward fuzzy PID control method which is suitable for the linearmotor servo controller was proposed after the deep study of PID control method,feedforward PID control method and fuzzy PID control method.(3) The linear motor servo control system models based on the control methods ofPID, feedforward PID, fuzzy PID and feedforward fuzzy PID were respectivelyestablished by using MATLAB/SIMULINK software. The unit step response and thesinusoidal response experiments of these control methods were then conductedrespectively. The simulation results show that the feedforward fuzzy PID controlmethod has the advantages of fast response and high control accuracy, which are betterthan the other three control methods. (4) The linear motor servo control algorithms based on the PID, feedforward PID,fuzzy PID and feedforward fuzzy PID were designed and compiled, respectively, anddownloaded into the PMAC motion controller to control the linear motor. Theexperiments under the condition of changeable loads were performed by using theplatform controlled by those four control methods respectively. The results show thatthe feedforward fuzzy PID control method is independent on the precise control model,and could avoid static error, reduce the tracking error. And the feedforward fuzzy PIDcontrol method which could change the control parameters in real time according to theworking environment is of strong adaptability. The simulation and experiment resultshave good consistency with the theoretical analysis.