A Study Of Sliding Mode Control For Permanent Magnet Synchronous Motor

In order to realize the high precision speed closed loop control of permanent magnet synchronous motor, usually adopts a mechanical type position sensor for measuring the rotor position and speed, but high resolution position or velocity sensors increase the cost of the system, limiting the driving device in harsh environment applications. Sensorless control has the advantage of reducing hardware complexity and cost, reducing the drive size, obtained better noise performance and high reliability, and easy maintenance. Therefore, the research of speed sensorless permanent magnet synchronous motor control has become a hot issue in the study of system.Chattering is the outstanding obstacle for the application of variable structure control, in order to improve the chattering, in exponential reaching law control is designed based on the variable exponent reaching law. The simulation results show that the control method effectively weaken the control system chattering, improves the normal motion segment quality. In order to improve the speed sensorless permanent magnet synchronous motor control system based on the parameter variations and load disturbances robustness, the sliding mode variable structure control is introduced to the model reference adaptive system, proposed a kind of speed identification method based on the variable structure MRAS of the permanent magnetic synchronous motor. The simulation results show that, the method has good dynamic and static performance, has higher estimation accuracy compared with the traditional MRAS, the parameter variations and load disturbances has stronger robustness. The main work of this paper are as follows:1. Analysis of the permanent magnet synchronous motor vector control principle, based on the current decoupling control of permanent magnet synchronous motor vector control system, is established based on voltage space vector pulse width modulation vector control system, using MATLAB/SIMULINK simulation to the system, the control scheme is verified by the feasibility. 2.Discusses the sliding mode variable structure control sliding mode controller and the basic principle and the basic design method of sliding mode variable structure control, according to the inherent chattering problem, introduce the reaching law control, is presented based on the variable exponent reaching law control of permanent magnet synchronous motor vector control system, the simulation results verify the effectiveness of the proposed control strategy.3.Based on the mathematical model of PMSM and Popov super stability law, design a model reference adaptive control for permanent magnet synchronous motor sensorless speed estimation scheme, select the appropriate adaptive law,based on this, the sliding mode variable structure control strategy is introduced, puts forward a variable structure model reference adaptive control strategy, simulation results validate the feasibility and validity of the solution.4. Summary of the full text, and then put forward on the sensorless control speed estimation and further establish and improve the experimental platform.