Model Reference Adaptive Control For Dynamically Synchronized Feed Between Two Linear Servo Position Loops

A kind of new control tactics: Decoupling control and Model reference adaptive control (MRAC) is proposed in this paper. The paper is the project named "Theory of Dynamic Precision synchronization Traverse and Research of Realization Methods for Linear Servo Dual Position Loops System (No-50075057)" as the background, which is supported by National Natural Science Foundation of ChinaDrive directly by linear permanent magnet synchronous AC motor, the controlled plant eliminates middle drive parts and avoids the effects of the mechanical transmission chains from rotary motions to linear ones. And LPMSM using high energy permanent magnet has strong electromagnetism thrust, lower cost, small electrical time constant and rapid response etc. Using linear permanent magnet synchronous AC motors as driving parts in gantry-moving type milling machine is first proposed in this paper, to bring their high-speed dynamic response ability into play for further realizing rapid synchronism.Decoupling control method is applied to the gantry-moving type milling machine synchrodrive in this paper. Two servo system outputs are coupled by mechanism framework. They are traversed as same speed instruction and have no direct-coupled connection on electrical parameters. As payload disturbances acting on the two motors can't be noncoincidental, the motor speeds change with the payloads of two motors, and cause position asynchronies. In order to return to the synchronous state, through changing the mechanism position asynchronies into electrical control variables. It is resumed synchronous state by control variable decoupling.A new adaptive control technology is first proposed in this paper and applied to the synchrodrive. For Gantry-moving type machining center servo system, in order to restrain the machine coupling influencing dual motors system, an adaptive decoupling control technology is first presented in this paper, and through feedforward decoupling; the dual linear motors controller's parameters will be modified by the feedback. The synchronous control caused bythe feedback resulting from the adaptive control law will keep synchronism with dual motors in position for realized synchrodrive.The results of simulations indicate that the proposed schemes have the advantages of rapid response, strong robustness, and low synchronous error. It means a lot for improving the synchronization precision of automatic control machine tool.