3MV多级多通道缩比开关自击穿特性

Self-breakdown characteristics of 3 MV multi-channel multi-stage reduced-model switch

通过短接电极间隙,开展了3MV多级多通道缩比开关不同间隙级数和单独触发间隙的自击穿特性分析,结果表明:自击穿电压随电极间隙距离不是线性增加,与Bradley经验公式存在差距。采用Ansoft软件模拟了实验开关不同级数的电场分布,得到不同级数开关电场分布的不均匀系数。结合缩比开关自击穿实验数据、Bradley经验公式和电场分布不均匀系数,在Bradley经验公式中加入开关作用时间因素和电场不均匀系数,得到一个Bradley外推公式,能较好地反应多级多通道气体开关的自击穿电压,使3MV实际开关自击穿电压理论值与实验值误差减小到5%。

The static characteristics of 3 MV multi-stage multi-channel closing switch（MMCS） should be defined.The self-breakdown characteristics of the MMCS with different number of gap stages and the trigger gap were studied by reducing the number of electric gap stages.The results indicate that the self-breakdown voltage varies nonlinearly with the gap distance,which deviates from the theoretical value obtained by Bradley empirical formula.The static electric field strengths of multiple gaps in series were calculated by using Ansoft program.By analyzing the experimental data,electric field uniformity coefficient and Bradley empirical formula,a new Bradley extrapolation formula was obtained,which can better reflect the self-breakdown voltage of MMCS and reduce the discrepancy between experiment and theory.The relative error was reduced to 5% by using the Bradley extrapolation formula.