大气压空气中同轴介质阻挡放电微放电特性

Analysis of Microdischarge Characteristic of Coaxial Dielectric-barrier Discharge in Atmospheric Air

为了更好的利用和研究介质阻挡放电技术,探讨了研究较少的同轴介质阻挡等离子体反应器的放电特性。因该类反应器2个介质阻挡层结构不一致,导致微放电行为在高频高压电源的正弦波电压的正、负半周内特点不同。研究从其放电的等效电路模型,流注放电击穿机理,以及在大气压空气中的放电实验等方面进行。结果表明,大气压下放电间隙8mm反应器时,放电电流波形在外加电源电压的正负半周期内不对称;分别呈现出明显的“似辉光放电”和“丝状放电”特点,单个微放电电流脉冲宽度约50ns,与外加电源电压极性和频率无关。

The study about discharge equivalent circuit model, streamer electrical breakout mechanism, and discharge experiment at atmospheric air shows that, because of the difference of the structure of the reactor＇s two dielectric barriers, microdischarge behavior of a coaxial dielectric-barrier plasma reactor is different in the positive and negative half period of the applied AC sine waveform voltage of the high frequency high voltage power supply. For a reactor of fixed discharge gap-8mm in atmospheric air, its discharge circuit waveform is anisomerous in the positive and negative half period of the applied AC sine waveform voltage, microdischarge behavior shows a obvious characteristics of ＂pseudo glow discharge＂ in the positive half period of applied AC sine waveform voltage, while in the negative half period it shows a obvious characteristics of ＂filamentary discharge＂; pulse width of a single microdischarge current waveform is about 50 ns, which is independent of the polarity, amplitude and frequency of the applied AC voltage.