Research On Drive Control And Algorithm Of Permanent Magnet Synchronous Motor

With the coming of the era of innovation,the constantly emerging of various kinds of theory,the technologies such as vector control,direct torque control magnetic field orientation gradually mature.Permanent Magnet Synchronous Motor has been paid more attention by researchers in the motor and control system fields.With the continuous improvement of Permanent Magnet Synchronous Motor control system performance,it has gradually been widely used in industrial,transportation,national defense and other fields.It is gradually replacing dc motor control system,and become the mainstream of the development of the control system.The main work of this thesis is on raising the stability and robustness of the permanent magnet synchronous servo system.The main contents of the paper are as follows:First,based on the permanent magnet synchronous motor drive control system,the basic principle and method of vector control are analyzed,and the mathematical model of permanent magnet synchronous motor is established.On this basis,the vector control scheme of Permanent Magnet Synchronous Motor is discussed,and the motor vector control structure diagram is given.The main structures of the hardware parts of the control system are introduced.Principles and realization of the main functional blocks of these two parts are illuminated.On the basis of the hardware experimental platform,the software is programmed with C language.Two close loop vector control with feedback of speed and current are realized.And the software program flow chart is given.Second,the adaptive PID controller: In the case of PID parameters and control system matching PID controller can achieve good control effects,but when the system parameters are uncertain or unknown,the PID parameters need to be continuously optimized.In this paper,the adaptive algorithm combined with the classical PID algorithm is applied to permanent magnet synchronous motor control system.Through the hardware experiment contrast,the composite PID controller canachieve a higher control precision.Third,the sliding mode variable structure controller based on a new hybrid reaching law: To improve the motor speed delay can effectively improve the operation efficiency of the motor.In this paper,On the basis of sliding mode variable structure control based on the exponential reaching law,a new reaching law is designed by combining the exponential reaching law and constant speed reaching law.The two laws are applied to permanent magnet synchronous motor control system.Comparing the control results,the speed delay and speed error of Permanent Magnet Synchronous Motor based on the new sliding mode variable structure controller are reduced by double.Fourth,the Model Reference Inverse Linear Quadratic optimal current controller based on extended Kalman filter: MR-ILQ can realize the nonlinear state feedback of the system,at the same time,realize the decoupling of d and q axis and the global linearization,so that the robustness and tracking performance of the motor control system can be further improved.But the motor has the problems that low speed operation is not smooth,the noise is big.In order to solve these problems,the extended Kalman filter was applied to current estimate,which was used to constitute the MR-ILQ optimal current controller based on the extended Kalman filter.The experimental results show that the controller can effectively solve the problems of motor running at low speed.Fifth,the Current predictive controller based on extended Kalman filter: Classic PID control is easy to appear problems such as lag,oscillation,and predictive control can realize fast track of command signal without overshoot,the extended Kalman filter has the advantages of the estimation and filtering,which can reduce the dependence of the predictive control on the mathematical model parameters of the control object.Experiments show that the improved method has realized the fast tracking of the command signal without overshoot,and the dynamic and static performance has been improved,the characteristics of the motor at low speed are also improved.