Large Gantry Machining Center Dual Linear Synchronous Motor Drive Control Technology

With the continuous improvement of requirement for precise parts, it's urgent to need CNC machine tools of high-speed and high-precision, gantry machining center is fully functional, has high machining accuracy, and can work out parts of micron or even nano, but it has many technical problems, double linear motor synchronous control of gantry machining center is the key one to realize high-speed and high-precision.In transmission strategy, the paper adopt permanent magnet synchronous linear motor to replace the traditional "rotary motor+ball screw", the permanent magnet synchronous linear motor can avoid the effects of the mechanical transmission chains from rotary motions to linear ones, and has strong electromagnetism thrust, lower cost, small electrical time constant and rapid response etc., which becomes the one of the executive machines in the high-precision and micro-feed servo system.In control method, in order to realize double linear motors synchronous control of gantry machining center, the paper adopt active disturbance rejection control (ADRC) to replace the traditional PID controller, ADRC is a new type of digital control technique in which system model is not relied on, the algorithm in ADRC is simple, fast without overshoot, and the identification of accuracy is precise, the capabilities of tracking and anti-parameter disturbances are strong. Meanwhile, the paper adopt fuzzy PID to replace the feedback controller. Compared with traditional PID, fuzzy PID does not depend on mathematical model of the object and has good robustness.Finally, the control strategy based on PID, based on ADRC and based on ADRC+fuzzy PID are simulated respectively by MATLAB software, the simulation results verify the control strategy based on ADRC+ fuzzy PID can get better control effect, synchronization error is low, and has good robustness.