Observer-based Control Research For Permanent Magnet Synchronous Motor

Permanent magnet synchronous motor(PMSM) has the characteristics of high power density, simple structure, high reliability, flexible control, and large torque.. In recent years, with the success of research about high performance permanent magnetic materials and the application of the power electronic technology as well as the development of advanced control theory and technology, the permanent magnet synchronous motor in electric vehicles, robot control, new energy wind power generation and many other aspects wins the widely used. The traditional permanent magnet synchronous motor(PMSM) utilize the installation of sensor and the current table to obtain the information of the motor speed and current. However, the installation of these devices makes permanent magnet synchronous motor's costs is increased, but also make its reliability is reduced, and system of internal and external environmental conditions limit the use of sensor. Therefor, an control method of permanent magnet synchronous motor based on observer is presented in this paper.The main work is as follows.1. LMI-based observer design for permanent magnet synchronous motor.According to the mathematical model of permanent magnet synchronous motor in d-q coordinate system, the sufficient conditions for the asymptotic stability of the full order observer error dynamic system are given based on the Lyapunov method and the stability principle of the control theory. In addition, to obtain the stability conditions based on LMI, the proposed design method is extended to the design of a nonlinear system with reduced-order observer. By numerical simulation experiments,the effectiveness of the method is verified.2. Observer-based sliding mode control for permanent magnet synchronous wind generator. For the mathematical model of the chaotic state permanent magnet synchronous wind power generator in d-q coordinate system, the full dimensional Luenberger observer is constructed to obtain the dynamic error equation. Further, the observer and sliding mode control are combinedly designed, and the design of the system controller is realized by using the sliding mode control theory. According to the Lyapunov stability theory, a stable sufficient conditions for the system are obtained. At last, the effectiveness of the proposed method is verified by numerical simulation experiments.3. Observer-based backstepping control for permanent magnet synchronous motor. According to the mathematical model of permanent magnet synchronousmotor in d-q coordinate system, the Luenberger observer is constructed by using permanent magnet q synchronous motor stator shaft current. Then, use the linear matrix inequality(LMI) processing technique to obtain the motor speed and the estimated value of the d axial current. Further, the closed-loop system controller is designed by using the backstepping control principle to realize the high precision tracking of the desired output signal. At last, the effectiveness of the proposed method is verified by numerical simulation experiments.