Study Of The Ac Motor Speed Control System Based On Fpga

From the20th century, frequency speed control can be applied to majority situations of electric drive. Because it is convenient for controlling the position variation and variable speed running of mechanical drive. Frequency speed control can significantly improve high efficiency of techniques and quality of products due to the independence of speed change on mechanical part, and it also can save more energy than former constant speed running, making great contribution to our national economy.FPGA(Field Programmable Gate Arrays)is a new type of IC(Integrated Circuit)in recent year. It has advantages of compactness, economy, high speed, low consumption, full integration and good applicability. It is easy to be developed and be maintained. So this type of apparatus was developed and applied in more and more fields. The technology of adjusting speed accuracy and working efficiency of AC induction electromotor receive considerable progress.In the paper, the hardware design scheme of AC variable frequ ency control system based on FPGA is proposed, the hardware platf orm consisting of FPGA,DSP minimum, current measurement circuit, speed and position measurement circuit is established, the PCB is f ulfilled and then the system is debugged. In addition, the principle of SVPWM is introduced in detail, and the implementation method based-on FPGA is mainly studied. According to its arithmetic, the SVPWM is divided into six modules, sector calculation, calculation the time of application of each basic vector, over-modulation contro1, SVPWM time generation, modulation wave generation and pulse generation respectively. The design, simulation and validation for ea ch module are first engaged in, and then the whole system is simul ated and validated, the PWM waveform is finally tested on the desi gned hardware platform.At last, the open-loop variable frequency test is experimented on the motor, the motor operates normally and the current in the stator is sine wave, the results indicate valid function of the SVPWM, and the expected requirements are achieved. With the short development cycle, flexible transplant and ability to embed to other system in the form of IP core, the SVPWM implemented using FPGA will be much valuable in application.