Construction And Realization Of Permanent Magnet Synchronous Motor's Controller Based On Equivalent Input Disturbance Estimator

The permanent magnet synchronous motor (PMSM) has become the mainstream of AC servo system recently. It has a very good low-speed performance, achieves a weak magnetic high-speed control, broadens the scope of the system's speed, and adapts to the requirements of high performance servo drive. With the high performance and lower prices of permanent magnet material, its application in the field of automation industrial production will become more and more widely. At the same time, PMSM is a nonlinear, structure varying and multiple states object. Because of the uncertain disturbance(for instance, the load, the internal parameters of the electrical disturbance), the high-precision motor control becomes more difficult. This paper approach a new method called equivalent input disturbance estimator to estimate the uncertain disturbance when motors are running, and then design the controller to suppress interference.Firstly, the structure of PMSM is introduced and its mathematical model of dq reference coordinates is presented. And then translate it to linear model based on the method of direct feedback linearization. Secondly, based on the structure of linear model, an equivalent input disturbance estimator combines the state observer and low-pass filter is designed. And then through the optimal control theory we design the parameters of estimator, through nonlinear control methods design controllers. Extended Kalman Filter(EKF) estimator is added to the structure of PMSM with equivalent input disturbance estimator. The rotor speed can be estimated based on the stator currents and stator voltages according to the proposed EKF. Based on Matlab/Simulink, the entire system simulation model is established. The simulation results of a PMSM system with equivalent input disturbance estimator demonstrate that the estimate of unknown disturbance is valid, what's more, the controller can bate the disturbance to ensure output track exception strictly. Thirdly, Based on dSPACE, a high-performance PMSM control system for the experimental program is designed. The experimental results proved the feasibility of this servo system.