The Research On Control Strategy Of Speed Control System Of Permanent Magnet Synchronous Generator

In recent years, AC driving system is widely applied in drive industry and becomes a mainstream in servo system. As the driving equipment in speed variable system, permanent magnet synchronous motor (PMSM) has the virtue of simple structure, small size, rapid response, precision, reliability and strong instantaneous overload capacity, and is widely used in high precision servo system, robots, numerical control machine, aerospace and so on. The main problem of the application of the PMSM is the high precision control in any environment. The research of the control strategy of the PMSM is of great scientific and practical importance.In this paper, the research status of control strategy and coordinate system conversion principles are briefly introduced and based on the introduction the dynamic model of the PMSM in the d-q coordinate system is presented. Through the analysis of some common methods and characteristic about the vector control, the speed loop and current loop control strategy of the PMSM is established.For the modeling uncertainties and exterior disturbances speed control of the PMSM, a linear active disturbance rejection control strategy of PMSM is proposed. Based on the design of the speed linear active disturbance rejection controller, the current linear active disturbance rejection controller is designed further, and the stability of the close loop system of the PMSM is analyzed. Computer simulation is done for the close loop system, and the simulation results show that active disturbance rejection controller performs well. Comparing with PI controller, active disturbance rejection controller reduces the steady-state error and improves the robustness of the close loop system.For the nonlinear and uncertainties speed control of the PMSM, an ESO based parameter self-tuning sliding-mode control strategy of PMSM is proposed. The reason of using sliding mode control in PMSM is for its appreciable features, such as design simplicity and robustness. To remove the disturbance impacts of switching gains, the ESO is used to estimate and compensate the disturbance. A parameter self-tuning strategy is proposed to adjust the switching gain, eliminating the chatting problem of PMSM, and improving dynamic performance of the closed-loop system. Simulation results show the effectiveness of the controller.