百kV/cm场强下SF6气体开关纳秒脉冲击穿场强和时延经验公式

百kV/cm高场强纳秒脉冲条件下，采用J. C. Martin经验公式估算SF₆气体击穿场强时，估算值与实验结果差异显著。为了进一步指导高场强脉冲气体开关设计，为开关工作状态调节提供依据，借鉴经典击穿场强经验公式形式建立了百kV/cm场强下SF₆气体开关纳秒脉冲击穿场强和时延与实验参数之间的关系，基于实验数据拟合形成了修正系数的击穿场强和时延经验公式。研究表明，百kV/cm场强和纳秒脉冲条件下脉冲电压斜率对开关击穿特性有重要影响，击穿场强与击穿时延相互关联。百ns至μs脉冲与几十ns脉冲气体放电机理的区别引起放电过程中击穿时延组成发生变化，导致了经典击穿场强经验公式估算值与实验结果的显著差异。修正系数的击穿经验公式可为电磁脉冲模拟器输出开关提供更为精确的工程设计依据。

Empirical formula of breakdown electric field and time delay for SF6 gas switch under nanosecond pulse and hundreds of kV/cm electric field

There are significant differences between the calculation results and experimental results by using J. C. Martin empirical formula to estimate the breakdown electric field for hundreds of kV/cm electric field and nanosecond pulse. To improve the design of pulsed gas switch and adjustment of working conditions, the relationships between the breakdown electric field and time delay and the experimental parameters based on the classical empirical formula is established. The empirical formula of breakdown electric field and time delay for SF₆ gas switch under nanosecond pulse and hundreds of kV/cm electric field is presented. It is indicated that the slope of pulse will affect the breakdown characteristics of nanosecond pulse in high electric field and the breakdown electric field is correlated with the breakdown time delay. The differences between the calculation results and experimental results are caused by the experimental conditions. The fitting expression of empirical formula can give more guidance for the design of output switch in the electromagnetic pulse simulator.