Precisely assessing plasma parameters holds paramount importance in investigating the arc extinguishing mechanism of semi-sealed splitter plate DC circuit breakers, refining the configuration of splitter plates, and optimizing the overall structural design of circuit breakers. Based on the principle of the Langmuir probe, a double probe diagnostic method is proposed to investigate the air arc plasma in the opening process of a DC circuit breaker. The diagnostic circuit of the probes is designed, and three sets of double probes are arranged to trace the evolution of the plasma density during the opening process. The research reveals that the plasma center density, measured by the diagnostic system during the opening process of the DC circuit breaker, is about 10²² m⁻³–10²³ m⁻³. This density is compared with the diagnostic results obtained by other methods, confirming the accuracy of the Langmuir double probe for plasma measurements in the DC circuit breaker. The study also revealed an exponential decay behavior of electron density along the radial direction of the arc. A mathematical model was employed to describe this phenomenon, establishing a relationship between the distribution of electron density and arc current.

中文翻译：

---

半密封分流板直流断路器电弧的参数表征

精确评估等离子体参数对于研究半密封分流板直流断路器的灭弧机理、完善分流板的配置以及优化断路器的整体结构设计具有重要意义。基于Langmuir探针原理，提出了一种双探针诊断方法来研究直流断路器分闸过程中的空气电弧等离子体。设计了探针的诊断电路，并布置了三组双探针来跟踪打开过程中等离子体密度的演变。研究表明，诊断系统在直流断路器分闸过程中测得的等离子体中心密度约为10 ²² m ^-3 –10 ²³ m ^-3。将此密度与其他方法获得的诊断结果进行比较，确认朗缪尔双探头在直流断路器中进行等离子体测量的准确性。该研究还揭示了电子密度沿电弧径向的指数衰减行为。采用数学模型来描述这种现象，建立电子密度分布和电弧电流之间的关系。