Study On AC Servo Control System Based On The Sliding Mode Observer

In ac servo control system, usually position sensor is installed in the motor rotor shaft. But these sensors not only increase the cost of control system, and greatly reduce the stability and reliability of the control system. With the fast development of microelectronics technology, modern power electronic technology and modern control theory, sensorless technique has been widely used. This dissertation with sine wave driven permanent magnet synchronous motor for the execution of motor, using the vector control strategy and the method of sliding-mode observer, has researched and accomplished the sensorless vector control of drive and control of permanent magnet synchronous motor system based on sliding-mode observer.Firstly, dissertation introduces permanent magnet synchronous motor structure and the characteristic, deeply research the vector control theory of permanent magnet synchronous motor, and confirmed by vector control scheme of rotor field-oriented. Secondly, the dissertation in-depth analyzes the basic principle of the sliding mode variable structure control, combines with the mathematical model of permanent magnet synchronous motor, design for sliding-mode observer of estimating rotor position and velocity, aiming at chattering phenomena existing in the observer and the problem of the precision low of the speed calculation, paper put forward method to improved.On this basis, this dissertation established a servo control system of PMSM, what has position, velocity and current three closed loop. And using of MATLAB software built a simulation model of the whole control system, servo control system of based on the sliding-mode observer of PMSM is studied. At last, this dissertation selects digital signal processing chip of TI company TMS320F28335 as the core control chip, designs hardware circuit of PMSM driving control system, and introduces software program flowchart of the whole servo control system. Through the research of experiment platform shows that the experimental results agree with the simulational results well, basically achieved PMSM sensorless control.