Research And Design On Energy Feedback Device Based On PWM Inverter

With the flying development of power electronic technology, the outstanding breakthrough of pulse width modulation (PWM) and all digital control theory, as well as the progress of the power electronic device, the application of AC drive system induced more and more wide focus. Also the issue of its energy utilization ratio received people's more and more concerns. In actual projects in used, the energy feedback system can solve the energy utilization problem while the motor in its braking condition. To optimize the feedback power quality, this thesis has designed a SPWM current close-loop energy feedback braking equipment.This thesis has introduced the key technology firstly, such as the principle of the energy feedback equipment and SPWM key technology etc, and then introduced the basic principle of a novel Active Controllable Energy Feedback Device. It also analyzed the voltage adaptive control and current close-loop tracking control strategy. The author introduced the disadvantages of those baking methods in use, such as complicated circuit hardware, hard maintenance, and expensive costs low rate. We used dsPIC30F2010 with the real-time controlling ability and strong calculating ability; this paper designed a energy-feedback baking equipment. The core of the equipment is dsPIC30F2010 produced by Microchip Company. The circuit of hardware is simple mainly include power circuit, control circuit, detect circuit, protect circuit, and so on. The software realized various kinds of function, including SPWM comparison, AD converter of circuit and voltage, input capture, protect functions and the analysis of the effect of dead time by software. Necessarily, we used MATLAB/Simulink to simulate the device, proved the reliability of the device.The author has also got the perfect single-phase and three-phase waveform through the experimental system at last, which has proved the dependability of the theory. In fact, the experiment indicates that the device has notable energy-saving effect. It operates securely and reliably and possesses enormous value of popularization.