The Research And Design Of AC-Motor Variable-Frequency Adjusting-Speed System Based On DSP

Vector control system of induction motor is based on vector coordinate transformation theory, motor unification principle and energy conversion. The stator current is decomposing two DC parts which orientated as the rotator magnetic field and controlled respectively by transforming coordinate. So magnetic flux and torque are decoupled. It controls the asynchronous motor as a synchronous way.Using digital signal processor (DSP), TMS320LF2407, which is special for motor control ,we develop a suit of speed-adjustable, speed-reliable and highly effective induction drive based on FOC principle. Realization of the main circut and the control circut is described. At the same time, a new Pulse Width Modulation (PWM) named Space Vector Pulse Width Modulation (SVPWM) method is introduced which is more effective.Based on hardware design, this paper also illustrated both algorithm and software design. Not only it introduced the main program and suspended program, but also how each model of SVPWM program worked. More importantly, this paper developed a new method of calculation of flux linkage, which ensures the accuracy and efficiency of Park transform. The results shows that can be used to control the motor successfully.