Research On The Asynchronous Motor Vector Control

As a result of the limitation of direct-current speed control modulation and thesuperiority of alternating speed control modulation and the unceasing development ofcomputer technology and electric power electronic device, the frequency conversion velocitymodulation technology of asynchronous motor is in the rapid development. The rapiddevelopment of microcomputer technology, the continous improvement of the computerrunning speed and the execution speed of instruction have made it possible that complexalgorithm carries on the true-time operation and execution by using computers. After theapplication and development in the past 10 years, the frequency conversion velocitymodulation performance of asynchronous motor has surpassed the direct current velocitymodulation system.At present, the asynchronous motor velocity modulation, vector control and direct torquecheck etc. are in detailed studies. This papar discusses the modulation method ofasynchronous motor, which has the advantages of superior dynamic and low-speedperformanc and wide velocity modulation scope.This paper analyzes and elaborates the mathematical model establishment of theasynchronous motor. It has established the mathematical models of asynchronous motors indifferent coordinate system and has shown that the model characteristics of the asynchronousmotor is a nonlinear system with more than one variables.This paper points out the process of implementing vector transformation and explainshow to work in pairs in the mathematical models of asynchronous motors in turns whileelaborating the vector control principles in asynchronous motor. It introduces thecomputational method of rotor flux linkage and designed the visualizer for rotor flux linkage.This paper analyzes the working principles of magnetic flux regulator, torqueregulator and RPM control and has designed all of them. Taking DSP as the control core, ithas also designed the hardware of the vector controlling system in the asynchronous motorand has written the software program.It has applied the SIMULINK tool software in MATLAB to carry on the simulation to the controlling system of magnetic closed loop vector and to give the simulation result and theanalysis of the result.