流注的产生和传播是空气间隙击穿中一个重要的物理过程,研究低气压下流注的产生和传播过程有助于理解空气间隙的击穿放电,对高海拔地区输电线路及输变电设备的设计和运行有着重要的意义。在可调节气压湿度的有机玻璃罐中,利用“三电极”结构,应用光电倍增管测量了不同气压湿度下,流注传播概率和平均传播速度随平板间电场强度的变化。通过数据拟合得到了流注稳态传播电场和相对空气密度以及湿度之间的经验公式。建立流体模型,对流注传播的动力学特性进行了仿真计算,得到的流注稳态传播电场及平均传播速度和实验测量得到的结果吻合得很好。结果表明:流注的传播场强随湿度、气压的增大而增大;在相同的电场强度下,流注平均传播速度随湿度、气压的增大而减小。利用仿真计算模型计算得到流注传播过程中的各个参数,分析了流注传播动力学特性随气压湿度变化的机制。
The streamer generation and propagation is a significant physical process during air gap breakdown. Research on streamer generation and propagation process under the low air pressure is helpful for understanding the process of air gap breakdown, which also has important significance on design and operation of transmission lines and equipments at high altitude area. In the paper, it was measured in a cylindrical chamber made of organic glass that the variation of the streamer propagation probability and average propagation velocity with electric field between parallel plates at different air pressure and humidity through photomultipliers in three-electrode arrangement. An empirical equation was obtained for explaining the relationship between streamer stability propagation field and relative air density, humidity. The simulation on streamer dynamics was carried out through fluid model. The obtained streamer stability propagation field and average propagation x;elocity from numerical computation was close to the experimental results. It was found that streamer stability propagation field increased with the rise of air pressure or humidity. The average propagation velocity decreased with the rise of air pressure or humidity under the same electric field. The mechanism of variation of streamer dynamics with pressure and humidity was obtained through the analysis on various parameters in the process of streamer propagation, which were calculated by the numerical simulation model