Research On The Servo System Of PMSM Based On Active Disturbance Rejection Control Technology

Due to the small volume, high efficiency, strong reliability and wide range of application, permanent magnet synchronous motor (PMSM) has been widely applied in the industrial automation field. However, as an actuator for servo control system, it is a strong coupling, variable parameters and nonlinear controlled object. PMSM could easily bring the nonlinear and uncertain control problems to the system, which is the control problem of PMSM servo system. In this paper, the active disturbance rejection control (ADRC) technology is applied to solve the problems effectively, which inherits the idea of the classic PID "based on the error to eliminate the error," and adopts a nonlinear control method without depending on the mathematical model of controlled object. Thus the application of the ADRC technology can improve the anti-interference capability, the control precision, the dynamic and static performance, and the robustness characteristics of the PMSM servo system.In this paper, we describe the background and significance of the topic in the beginning. Then the research of the topic is established, by analyzing and studying the overview of the development of the servo system, and the studying status of the servo system of permanent magnet synchronous motor, control strategy and algorithm.Secondly, the mathematical model of PMSM is deduced in detail, and the vector control principle of PMSM is analyzed as well. The control method of id= 0 is chosen for the system to be decoupled, so the electrical excitation and torque of motor will be under the control of independent.Then, the specific mathematical model of active disturbance rejection controller is analyzed at length, after the brief description of the development and the superiority of ADRC. And the equations of state are built for the three links of tracking differentiator, extended state observer, nonlinear state error feedback control law, which they belong to the active disturbance rejection controller. According to the specific characteristics of them, we would respectively turn their parameters and give out their tuning method.Finally, we would design the PMSM servo system based on the active disturbance rejection controller, combined with the mathematical model of PMSM. By building the Simulink simulation model of the system, we separately study the dynamic performance, the tracking performance and the disturbance rejection performance. The results shows that the system owns accurate tracking ability, the good dynamic and the static performance, very strong anti-interference ability with the action of ADRC, which have been obtained as expected.