The Design Of Control System Of The Plasma Power Supply For Sewage Treatment Based On DSP

With the developing of the society, the lack of water is becoming more and more serious. Because the pollution of water is serious, we need the most effective method to solve this problem. The plasma technology is a new technology to the wastewater treatment, it has three effects: high-octane, ozone oxidation, ultraviolet radiation decomposability. Because of the predominance of the plasma technology, this method is becoming the hotspot in the world recently. The principium of the plasma technology is that the plasma which is produced by electric field reacts with the contamination in the water.The plasma technology has three equipments:high voltage power supply,the control system of the power supply and reactor.The power supply is used for the production of the plasma.The reactor adopts the line board configuration.This paper introduces a noval,high-frequency and high-voltage AC+DC power supply.This power supply makes corona-discharging FGD apply in the industry.The AC+DC power supply produces effective and steady streamer at a broad range.DC spreads cation and free radical to a broad range and enhances the efficiency of the plasma technology.AC makes the discharge stronger and increases the energy density and free radical quantity in the reactor.The power supply is the most important equipment in the waste water, so the control system of the power supply is very important.This paper is mainly study on the control system. The system is designed on the TMS320LF2407.The control system uses integral separation PID controlling algorithm to control the SCR pulse circuit for adjusting the DC output and changes inverter switching circuit to change the AC power frequency to change circuit resonant state.It has a Liquid Crystal Display(LCD) module to display the real-time state variables and keyboard to setup the voltage,the current and PID paramaters.The control system can communication with a computer with a computer following the RS232 protocol,an intelligent interface is designed to remotely control the plasma power by Visual Basic 6.0.