介质阻挡放电等效电容的测量与分析

Measurement and Analysis of Equivalent Capacitance in Dielectric Barrier Discharge

为深入理解放电机理并优化介质阻挡放电反应器设计,提高运行效率,介绍了通过Lissajous图形计算介质阻挡放电气隙等效电容Cg,电介质层等效电容Cd及负载电容的方法,通过实验研究了外加电压及气隙距离的变化对Cd、Cg和总电容C的影响。结果表明,给定介质厚度和电源频率时,随外加电压的增加,Cd逐渐增大,在相同的电压下,Cd随气隙距离的增加而减小;Cg随外加电压的增大而减小,在相同的电压下,Cg随气隙距离的增加也是减小的;C随外加电压先增大再减小,中间会达到一个最大值,相同电压下,随着气隙距离的增加,介质电容减小,而且,随着气隙距离加大,介质电容所能达到的峰值会减小。

In order to settle the match problem between dielectric barrier discharge （DBD） reactor and the DBD＇s power, a method of calculating the equivalent capacitance in dielectric barrier discharge by dint of Lissajous figure is introduced. The influences of change of applied voltage and gap distance on Cd （barrier capacitance）,Cg （gas gap capacitance） and C（load capacitance） were experimentally studied. The results show that when the barrier thickness and frequency are constant Ca will increase with the increase of voltage, at the beginning, the increased extent is big but turns small or even mild when the voltage reaches a certain value, and Ca will decrease with the increase of gap distance under the same voltage; Cg will decrease with the increase of voltage for the decrease of air dielectric constant, and it will decrease with the increase of gap distance under the same voltage. C will increase first and then decrease with the increase of voltage and will decrease with the increase of gap distance under the same voltage. The peak value of Cwill decrease with the increase of gap distance. So in order to improve the working efficiency of DBD reactor, most of the voltage applied to the reactor should be distributed to the gas Sap rather than the barrier. Choosing thin barrier with big value of dielectric constant and decreasing the gap distance or increasing the voltage can also reach the aim.