An investigation into the cumulative breakdown process of polymethylmethacrylate in quasi-uniform electric field under nanosecond pulses

作者：Zhao Liang^*; Su Jian Cang; Zhang Xi Bo; Pan Ya Feng; Wang Li Min; Fang Jin Peng; Sun Xu; Lui Rui

来源：Physics of Plasmas, 2013, 20(8): 082119.

DOI：10.1063/1.4818437

A group of complete images on the discharge channel developed in PMMA in quasi-uniform electric field under nanosecond pulses are observed with an on-line transmission microscope. The characteristics of the cumulative breakdown process are also generalized, which include initiating from the vicinity of the cathode, developing to the anode with a branch-like shape, and taking on a wormhole appearance when final breakdown occurs. The concluded characteristics are explained by referring to the conceptions of "low density domain" and "free radical" and considering the initial discharge channel as a virtual needle. The characteristics are helpful for designers to enhance the lifetime of insulators employed on a nanosecond time scale.

• 出版日期2013-8
• 单位西北核技术研究所