Observer-based Robust Stability Analysia And Controller Design Of PMSM

Permanent magnet synchronous motor(PMSM) with its simple structure, reliable operation, small size, low loss, high efficiency, has been widely used in CNC machine tools, electric vehicles, robots etc.. Research and analysis of high performance permanent magnet synchronous motor control system has important significance and application value. However, PMSM is a nonlinear system with multi variable, strong coupling, such as the existence of current coupling, saturation, system parameter perturbation and external disturbance and many other negative factors, which directly affects the performance of the control system to improve. According to the existing analysis on the survey of PMSM, the deeply analysis and design of PMSM control system is studied to further reveal the nature of the PMSM, provides a new way for the analysis and design of PMSM. The main research work and innovations are as follows:(1) For uncertain PMSM control system, the sufficient conditions for robust stability and stabilization of the system is proposed. On the basis of the deep analysis of PMSM mathematical models of different coordinates, with the number of parameter perturbation and external disturbance in PMSM system, the analytical solution based on the Laplace transform is presented. Then, using Gronwall-Bellman lemma to obtain sufficient conditions for asymptotic stability of the zero solution of the system. Furthermore, based on the Lyapunov stability theory, the linear matrix inequalities(LMI)-based stability condition is established by using matrix algebra transformation. Last, based on the above stability conditions, the robust state feedback controllers for PMSM uncertain system.(2) For uncertain PMSM system, a robust feedback control design method based on the state observer is devoleped. Considering the system parameter uncertainty, a design method of a full order observer is firstly proposed. The stability condition of closed-loop system is obtained by using the Lyapunov stability theory. Then, by using matrix singular value decomposition techniques, the stability condition is transformed into a tractable LMI condition. According to the stability condition, the observer-based feedback controller for permanent magnet synchronous motor is provided to realize the tracking control of motor speed.(3) For permanent magnet synchronous generator(PMSG) system, a chaotic control method is first devised by using the inverse system control theory and the method of internal model control. Then, the full-order and reduce-order fault observer are designed for PMSG uncertain fault model, respectively. dimension reduction fault observer design converges to the original system of all peacekeeping. Further, the actuator fault detection and fault reconstruction methods as well as the numerical algorithm are proposed for PMSG fault system.(4) For the speed tracking problem of PMSM system, by using the backstepping design method, a backstepping controller is first designed, which can accurately track the permanent magnet synchronous motor’s speed and current. As for not all the state can be measured, a sliding mode observer is then designed based on Lyapunov stability theorem. Since the sliding mode observer can be used to estimate the status of PMSM, the state observer will be applied to the backstepping controller, thus, to realize the tracking control of PMSM system. Finally, the uncertainty model with multiple unknown coefficients is established for PMSM system, where the number of pole pairs P is the only one parameter assumed known. With this uncertain PMSM system, an adaptive backstepping controller is also proposed as to realize the high precision control of PMSM system.