The Design And Study Of VVVF Power Supply Based On DSP

With modern technology, the rapid development of power electronics, the applications of VVVF power supply are being used increasingly in many fields.At the same time all aspects of performance of variable-frequency power supply has also made increasing demands. A good variable-frequency power output waveform requires not only excellent dynamic and static performance, but also strong adaptability with the load.The emergence of high-performance DSP controllers makes variable-frequency power supply to all-digital control a reality. Digital control system has zhe advantages of integrated high anti-interference capability, flexible control, advanced control algorithms can be realized and easy real-time control. Using DSP as the the core of DC-AC inverter control, you can easily use the software flexibly and accurate on-line control and fault detection. Thus, the design of digital control power supply has become the trend.This topic is for the actual project of variable-frequency transformer power supply.lt discusses the MC56F8346DSP chip as the control unit in the design of inverter transformer power supply. Paper first introduces the topology and the theory of variable-frequency power supply, and the design of the main circuit of the AC-DC-AC single-phase voltage source inverter, and the control circuit with core of MC56F8346DSP. Then paper studies three kinds of SPWM digital generation algorithm based on the analysis of the principle of SPWM control technique, and the output harmonic and characteristics were analyzed. The main part of this paper is the overall software and hardware design of variable-frequency power supply. The hardware design is made up of the design of overall structure of the system and the design of selection of individual modules and parameters, which includes the design of rectifier and filter circuit, inverter circuit, driving circuit, LC low-pass filter and other external circuit, and the parameters of the power device were selected. The software design of the control system consists of the given of the voltage and frequency, data calculation program, the sampling of output voltage and current, PID regulator, SPWM output, and several other components. Finally, the output waveform is given, and to be analysed,through the experiment and debug of the prototype.