Research On Control Strategy For High Performance PMSM Servo System

Currently, most CNC machine ball-screw drive systems use permanent magnetsynchronous motor servo system. The essence of the ball-screw system is permanentmagnet synchronous motor servo position control system. Therefore, the servo systemperformance and is closely related to the performance of the ball-screw system.Studying of high-performance permanent magnet synchronous motor servo systemcontrol strategy, ball-screw system can improve the accuracy and efficiency of thecutting, this thesis studies this problem as follows:First of all, establishing PMSM mathemetical models in different coordinate.Analysis of the PMSM vector control programs and current control scheme, which canmeet the performance requirements of the ball-screw system. PMSM electricalparameters can influence the design of the mechanical current controller, speedcontroller and position controller, proposing synchronous motor parameter identificationscheme for the ball-screw system.Secondly, to reach a destiny of a good anti-load disturbance ability, this paperpresent a reduced-order torque observer to compensate in the current loop. Thereduced-order torque observer has more brief structure with the full-order torqueobserver. After using the current loop feed-forward compensation device, from theresult of the simulating and experiment, the speed fluctuation caused by load changingis greatly reduced.Thirdly, in order to solve the contradiction between response time and overshoot ofthe PID controller, proposing a PI-PD controller. In such a position servo system, thecontroller can be used in reducing the dynamic error and effectively improve the systemposition control accuracy.At last, building a high-performance32-bit microcontroller based on InfineonTC1767as the core platform for PMSM Servo System Control, compile the softwarecontrol algorithm to control the servo motor. The result of the experiment indicates thatthe control scheme could greatly enhance the robustness and disturbance rejection byusing the current loop feed-forward compensation scheme; PI-PD controller canimprove the positioning accuracy of the servo system, there is a good follow-upcharacteristics.