Research Sensorless Control Of Permanent Magnet Synchronous Motors

Permanent magnet synchronous motor as an application prospects, coupled with a strong, low energy consumption, high reliability and precision, etc.,has attracted more and more attention in the practical application and to use. In a real system, how to get the rotor information has become an important part of the control system. Due to the presence of the installation by installing the difficulties poor accuracy and system cost increase, and many other defects sensor on the rotor, so sensorless technology that used to get the motor rotor position information will become the next hot research. But most studies focus within a speed range. This applies mainly through the study of different stages of sensorless speed control method is proposed for the permanent magnet synchronous motor in the full range of composite sensorless control technology. The main contents are:(1) The space vector control algorithm implementation is studied in practical permanent magnet synchronous motor vector control system and the whole system is established.(2) Based on Salient features for buried type permanent magnet synchronous motor is estimated in the range of zero-speed and low-speed rotor position by rotating high frequency voltage injection method. Through detailed analysis of the estimation method and the principle of rotation of rotor position high frequency voltage injection method, established a sensorless vector control system based on rotating high frequency voltage injection method is established and further simulation analyzed.(3) The principle of sliding mode observer position detection is studied in high-speed permanent magnet synchronous motor and raises an improved sliding mode observer. Using saturation function replaces switching function and the feedback signal passes through Kalman filter in order to obtain high-precision rotor position information. At end, the entire control system simulation is verified.(4) Using hysteresis switching algorithm merges two kinds of speed stages for different sensor-fusion technology. Finally, this paper completes composite sensor-based control methods. Based on TI Introduces High Voltage Digital Motor Control experiment board, sliding mode observer is designed and applied to the actual system which validate the experimental results show that the design of the sliding mode observer in the system can be a good estimate of the actual position of the rotor.