Measurement and analysis of discharge current in dielectric barrier glow discharge at atmospheric pressure

Dielectric barrier discharge has become a hot issue in low temperature plasma research field because of wide prospect for its application in industry. In the present paper, an uniform glow discharge was realized in atmospheric pressure helium with a parallel planar dielectric barrier discharge device and an uniform plasma was generated in helium at atmospheric pressure. Electrical method was used to separate the discharge current from the total current signal and the waveform of discharge current could be obtained. The relations among the discharge current, applied voltage, gap voltage and wall charge during the uniform glow discharge were used to analyze the dynamical behavior of wall charges during their accumulation. The results show that the wall charges were mainly accumulated during the existence of discharge current pulse, while the quantity of wall charges continued to increase until the gap voltage changed its polarity after the disappearance of discharge current pulse, and finally the quantity of wall charges decreased until the next breakdown. These experimental results are important for the further study of wall charges' effect in the dielectric barrier glow discharge and its application in industry.