Research On Multi Parameter Control Method Of Dielectric Barrier Discharge Power Supply

Plasma is the fourth state of matter,and its application prospect is very extensive.At present,plasma is produced by Dielectric Barrier Discharge(DBD)under atmosphere.The DBD requires high voltage AC power supply,and discharge effect correlates directly with voltage,frequency and waveform.Relatively speaking,The higher the voltage and the frequency,the better the effect of discharging,while the resonant frequency of the load also have a certain impact on the power efficiency.Based on this point,combined with the load characteristics of DBD,we developed a kind of power supply with adjustable voltage and automatic frequency tracking,which makes the active power of the power supply to achieve the maximum.This thesis focuses on the multi parameter control methods of DBD power supply,so that the parameters are always in the optimal state.This paper mainly includes the following aspects:(1)Topological design of power inverter circuit.According to the characteristics of capacitive load of DBD generator,using compensating inductance to constitute the resonant circuit.Based on the analysis and comparison of series parallel resonant circuit,finally,we select the series resonant as the main circuit structure of dielectric barrier discharge.(2)Design of control circuit.According to the selected series resonant circuit structure,using the PWM pulse width modulation control method to achieve an adjustable output voltage.Considering the load resonant frequency will change because of the outside world,a frequency tracking circuit based on phase locked loop(CD4046)is designed to improve the efficiency of the whole power supply.(3)Power circuit design.Power supply system mainly includes: input rectifier filter circuit,inverter circuit,control circuit,drive circuit,frequency tracking circuit,protection circuit,auxiliary power supply,etc.(4)Power result analysis.The experimental results show that the output voltage can be adjusted and automatic frequency tracking.The power supply is applied to the DBD generator,and the wave-forms of the important nodes are collected to verify the influence of the load on the frequency.