In this article, the sheath growth of the vacuum circuit breaker and its initial conditions of the calculation are introduced. The images of cathode spots distribution and waveforms of postarc current under different frequencies are obtained by medium- to high-frequency current breaking experiments. The quantitative relationship of $D$ and $di/dt$ with the variation of current frequency $f$ and current amplitude $I_{m}$ is obtained by fitting the data. The reasons for the change of postarc current parameters are reasonably explained by the analysis of equivalent circuit and plasma movement process. Combined with the continuous transition model (CTM) and its initial calculation conditions, the influence of the cathode spots distribution diameter $D$ and $di/dt$ after the current zero crossing on the sheath growth is analyzed. An initial postarc plasma density calculation model which is suitable for each current frequency is proposed which makes the calculation of the sheath growth more accurate, especially when applied to medium- to high-frequency current conditions.

中文翻译：

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考虑等离子体运动和分布的弧后鞘生长过程研究

本文介绍了真空断路器的护套生长及其计算的初始条件。通过中高频电流开断实验，得到了不同频率下阴极点分布和弧后电流波形的图像。的数量关系 $D$ 和 $di/dt$ 随着电流频率的变化 $f$ 和电流幅值 $I_{m}$ 是通过拟合数据获得的。通过等效电路和等离子体运动过程的分析，合理解释了弧后电流参数变化的原因。结合连续转变模型（CTM）及其初始计算条件，阴极光斑分布直径的影响 $D$ 和 $di/dt$ 在分析鞘生长上的电流过零之后。提出了适用于各电流频率的初始弧后等离子体密度计算模型，使鞘层生长的计算更加准确，特别是在应用于中高频电流条件时。