Vacuum electrical breakdowns, also known as vacuum arcs, are a limiting factor in many devices that are based on application of high electric fields near their component surfaces. Understanding processes that lead to breakdown events may help mitigate their appearance and suggest ways for improving operational efficiency of power-consuming devices. Stability of surface performance at a given value of the electric field is affected by the conditioning state, i.e., how long the surface was exposed to this field. Hence, optimization of the surface conditioning procedure can significantly speed up the preparatory steps for high-voltage applications. In this article, we use pulsed dc systems to optimize the surface conditioning procedure of copper electrodes, focusing on the effects of voltage recovery after breakdowns and variable repetition rates as well as long waiting times between pulsing runs. Despite the differences in the experimental scales, ranging from ${10}^{-4}\mathrm{s}$ between pulses up to pulsing breaks of ${10}^5\mathrm{s}$, the experiments show that the longer the idle time between the pulses, the more probable it is that the next pulse produces a breakdown. We also notice that secondary breakdowns, i.e., those which correlate with the previous ones, take place mainly during the voltage recovery stage. We link these events with deposition of residual atoms from vacuum on the electrode surfaces. Minimizing the number of pauses during the voltage recovery stage reduces power losses due to secondary breakdown events, improving efficiency of the surface conditioning.

中文翻译：

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直流电压脉冲对Cu表面附近高真空电击穿的影响

真空电气击穿（也称为真空电弧）是许多设备中的限制因素，这些设备基于在其组件表面附近施加高电场的情况。了解导致故障事件的过程可能有助于减轻其外观，并提出提高耗电设备运行效率的方法。在给定的电场值下，表面性能的稳定性受调节状态的影响，即表面暴露于该电场的时间。因此，表面调节程序的优化可以显着加快高压应用的准备步骤。在本文中，我们使用脉冲直流系统来优化铜电极的表面处理程序，着重于击穿和可变重复率以及脉冲运行之间的较长等待时间之后的电压恢复效果。尽管实验规模有所不同，但从${10}^{-4}\mathrm{s}$ 在脉冲之间，直至 ${10}^5\mathrm{s}$实验表明，脉冲之间的空闲时间越长，下一个脉冲产生击穿的可能性就越大。我们还注意到，二次击穿，即与先前的击穿相关的，主要发生在电压恢复阶段。我们将这些事件与真空中电极表面残留原子的沉积联系起来。使电压恢复阶段的停顿次数最少，可减少由于二次击穿事件而导致的功率损耗，从而提高表面调节的效率。