中文摘要：

为研究介质阻挡放电（DBD）过程中等效电容的变化情况,利用高频高压电源,进行了大气压氦气介质阻挡单脉冲和多脉冲辉光放电试验,利用外施电压、回路电流计算得到放电Lissajous图形,并与直接测量的Lissajous图形进行了对比。确定了放电电流波峰和波谷在Lissajous图形上的对应位置,计算了放电截止和放电进行阶段气隙和介质的等效电容,分析了等效电容变化的原因,并且探讨了放电的物理过程。结果表明：计算得到的Lissajous图形与测量所得的Lissajous图形一致;介质等效电容在放电截止阶段保持不变,但在放电进行阶段随电流脉冲变化而变化,并且在电流峰值处最大;放电物理过程主要受到外施电压和介质表面电荷量的变化速率影响。

英文摘要：

In order to investigate the variation of equivalent capacitance during dielectric barrier discharge （DBD）, single pulse and multi-pulse discharges were obtained using a high-frequency power supply in atmospheric-pressure helium. By measuring applied voltage and loop current, Lissajous figures were calculated and compared with those which were directly measured. The equivalent capacitance of the gas gap and dielectrics during the discharging and cutting-off phases were calculated with the corresponding relationship between the peaks and valleys of current pulse and the points on Lissajous figures. The reasons of variation of the equivalent capacitance were analyzed, and the physical process of discharge was discussed. The results show that the equivalent capacitance can be studied by using calculated Lissajous figures instead of the measured ones. The equivalent capacitance keeps unchanged during the discharge cutting-off stage, but changes with current during the discharging stage and reaches its maximum at the peak point of current pulse. And the process of discharge is mainly affected by the changing rates of applied voltage and space charges.