Research On Control Methods Of Servo System Based On Permanent Magnet Synchronous Motor

This paper mainly studied control methods of AC servo system, including common PI control, proximate time-optimal servomechanism(PTOS), composite nonlinear feedback(CNF) control, and a mode switching control(MSC) scheme based on PTOS and CNF. The structure of PI controller is simple and easy to implement, PTOS controller has a fast response time, the response overshoot of CNF control is small, and the response time and overshoot of MSC scheme are between PTOS’s and CNF’s respectively. This paper takes TMS320F28069 as the core chip of the overall control system, using permanent magnet synchronous motor(PMSM) as the system control object, designs a vector control system namely PMSM position servo system based on space vector pulse width modulation(SVPWM) technology. Furthermore, the paper has done a detailed theoretical research and practical exploration on control strategies and control methods of AC servo system.Firstly, the research situation and development trend of the control strategies for PMSM servo system are introduced in this paper, then SVPWM technology, vector control strategy, and PI, PTOS, CNF and MSC scheme are introduced in detail. Under MATLAB\Simulink, the PMSM servo system model has been built for the four control schemes respectively, simulation results verify that under PTOS, the system has the fastest response, under CNF the overshoot is small, while the response time and overshoot are between PTOS’s and CNF’s under MSC, then determining the research content and the main work of this paper.Secondly, On the basis of theoretical research and system simulation, this paper gives the software design processes and describes the principles of hardware platform for PMSM position servo system, and then for the problems encountering during the experiment, gives specific solutions.Finally, after each module programmed, this paper presented the test results of each module on the hardware platform based on TMS320F28069, ensuring the correctness and rationality of programming, and then all modules were integrated together to complete the building of position, speed and current three-closed loop. Debugging the servo system respectively for PI control, PTOS control, CNF control and MSC scheme, the experimental results obtained are consistent with the theoretical analysis and simulation results, verifying the correctness and reasonable of the overall system design, and laying a foundation for further research.