Research Of High Frequency Response Fast Tool System Control Strategy Driven By Linear Motor

High performance fast tool linear servo system is the key technology for ultra-precisioncomputer numerical control(CNC) high speed machining of freeform optics surface, whichrequire linear motor servo tool system has better tracking ability for the high-frequencyperiodic input signal in CNC machining, and has a strong ability to inhibit the load disturbance.For this problem, the control strategies of the system under high frequency periodic signal isstudied. The main contents are as follows:First, a large amount of domestic and foreign literatures is accessed with in-depthunderstanding about the structural characteristics of the high frequency response fast toolsystem driven by linear motor, on this basis the mathematical model of permanent magnetlinear synchronous motor (PMLSM) that driven FTS is established, the disturbances caused bymultiple factors to linear servo is analysed.Then for FTS driven by PMLSM exist the ripple thrust disturbance, end effectdisturbance due to the motor itself and cutting force disturbance when processing andproblems of uncertainty disturbance, select to design the immune control strategy that hasrobustness and adaptability, at the same time for the FTS required the tracking accuracyproblems under high frequency short stroke periodic signal, designed the repetitive controller.This thesis combined the two methods, and designed a new type of immune repetitive controlmethod that combination not only the immune system has strong robustness and adaptabilityin the large disturbance and uncertainty environment, make the servo system has theadvantages of rapid response, simple design, but also combined with repetitive control for theperiodic signal of high frequency tracking performance. In the MATLAB environmentsimulation studyed for the FTS immune repeat feeding system, the simulation results showsthat: this control scheme can make linear servo FTS has better tracking control accuracy,strong resistance disturbance performance to high-frequency sinusoidal signal, having a fastresponse relative to square wave signal.Thirdly in order to further improve the tracking accuracy, speed and robustness of FTSdriven by linear servo system, the adaptive fuzzy sliding mode control of the system is studied.First, using adaptive fuzzy control method to fuzzy approximation the discontinuous controlamount of the traditional sliding model controller. At the same time the corresponding adaptive algorithm is designed to compensate for the lack of control amount of fuzzy controllaw, so as to effectively reduce chattering. Simulation results show that: algorithms used in theservo system can soluted the problem of high frequency tracking, has faster response speed,have strong robustness to load disturbances.