Research on the Extinguishing Peak Characteristics of Air Arc in the Model Extinguishing Chamber

In order to investigate the waveform changes of arc voltage before zero crossing in the arc extinguishing chamber, this paper constructed a model of the arc extinguishing chamber for arc ignition experiments. The experiment collects and records the arc voltage waveforms using an oscilloscope and captures the dynamic characteristics of the arc during the experiment with a high-speed camera. The experiment is conducted under two conditions: free arcing and applying an external magnetic field. In the case of free arcing, by varying the input current levels, it is found that the appearance of the extinguishing peak is not simply proportional to the current level; if an extinguishing peak occurs, the arc shape extends towards the outlet in a “ <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\Lambda$</tex> “pattern. Under the condition of an external magnetic field, changing the input current level results in the constant existence of arc extinguishing peak; and the lower the current level, the higher the extinguishing peak. In addition, under the condition of an external magnetic field, the influence of different outlet sizes on the waveform of arc voltage was investigated. Additionally, under the external magnetic field condition, the study explores the effect of different exhaust port sizes on the arc voltage waveform. Experimental results indicate that with larger exhaust ports, the stable arcing voltage and extinction voltage values are slightly higher than those with smaller exhaust ports. Through analysis, it is concluded that the observed variations in arc voltage waveforms are collectively influenced by factors such as temperature, airflow field, and magnetic field.