Research On Speed-Sensorless Vector Control System For Asynchronous Motor

Along with the dramatic development of electronic technology and computer science, the speed regulation technology of alternating current machine has made considerable progress. The speed-sensorless vector control of asynchronous motor has become a focus gradually as an important approach direction in modern alternating current machine control.In this dissertation, based on the theory of speed-sensorless vector control system, the vector control system using model reference adaptive and speed adaptive rotor flux observer is simulated. To realize the designed system, necessary hardware and software are also schemed.Firstly, progress of control strategies of alternating current motor and speed-sensorless vector control technology in recent years is summarized, and the advantages and disadvantages of different strategies are enumerated and compared. Then,the principles of vector control, coordinate conversion and space vector pulse modulation (SVPWM) are expounded; Mathematical models of asynchronous motor in different coordinates are introduced. That offer theoretical foundation for further research on the speed-sensorless vector control system for asynchronous motor. Secondly, two kinds of speed-sensorless vector control system based on model reference adaptive system (MRAS) and full order speed adaptive rotor state observer are discussed. And the state observer, speed adaptive law, feedback gain matrix of second kind of vector control system are deduced in detail. Based on these ,the simulations of speed-sensorless vector control system based on model reference adaptive system and full order speed adaptive rotor state observer are realized in MATLAB/Simulink, and the simulation results are discussed and compared. Finally, the software and hardware based on TMS320F2810 to realize speed-sensorless vector control system for asynchronous motor are schemed.The results of the simulation show that the two kinds of speed-sensorless vector control systems for asynchronous motor are both effective and rational. The speed estimation of full order speed adaptive rotor state observer is more accurate than MRAS, because the error-corrected loop is used.