激励器参数对纳秒脉冲表面滑闪放电特性影响

Effect of Actuator Parameters on Slide Discharge Characteristics Driven by Nanosecond Pulse

利用三电极激励器结构,通过纳秒脉冲叠加负直流激励方式产生表面滑闪放电。研究电极间距、阻挡介质材料及其厚度对纳秒脉冲表面滑闪放电电气及光学特性的影响,并分析基于三电极激励结构的表面介质阻挡放电模式转换规律。实验结果表明,不同电极间距下纳秒脉冲表面滑闪放电电压激发差值不同,随着电极间距增大,电压激发差值逐渐增大,而介质表面平均电场强度先增大后减小,电极间距为25mm时为最优值,能在较低的电压激发差值条件下产生较高能量。此外,表面滑闪放电在不同电极间距条件下均存在3种放电模式,随着激励器电压差值的增大,放电模式由典型表面介质阻挡放电逐渐转变为表面滑闪放电,并最终转变为火花放电。介电常数较低的阻挡介质材料沉积能量较多,而介质厚度对表面滑闪放电电压激发差值影响较小,但激励器厚度较小时消耗的功率相对较大,能量利用率较低,不利于获得大面积等离子体。

In this paper, a new three-electrode structure was applied to generate sliding discharge driven by a nanosecond pulse source and a negative DC source. The effects of the electrode gap, dielectric materials and dielectric layer thickness on the electrical and optical characteristics of sliding discharge were investigated. In addition, the discharge mode based on the three-electrode actuator was analyzed. The experimental results show that the voltage excitation values of sliding discharge are disparate at different electrode gaps. With the increase of electrode gap, the voltage excitation value increases gradually, while the average electric field intensity on the layer surface has the maximum value. There is an optimal value when electrode gap is 25 mm, which can form more energy at a lower voltage excitation value. Moreover, with the increase of electrode gap, the discharge mode changes from typical SDBD to sliding discharge, and finally to spark discharge. The barrier dielectric material with lower relative permittivity is able to deposit more energy. The dielectric layer thickness slightly affects the voltage excitation value of the sliding discharge but the consumed power, and the energy utilization efficiency is low with thin dielectric layer, which is unfavorable to obtain large-area plasma.