直流48 V 回路における開離時アークの移動範囲と接点表面の曲率半径の関係

摘要

接点表面の曲率半径が異なるAg 接点を用いて、DC48V／6－24A の抵抗性負荷回路内で、開離時アークを発生させる・開離時アークの様子を高速度カメラで撮影し、その時の電圧・電流も同時に測定する．高速度カメラで撮影した開離時アークの画像から陰極輝点領域の挙動を解析する．その結果，接点接触時の回路電流と曲率半径の違いによって開離時アークの挙動に特徴的な変化があることが確認できた．また、曲率半径が大きい時にアーク継続時間が長くなる傾向が確認できた．%Break arc generated in a DC48V/6-24A resistive circuit using Ag contact that the radius of curvature of a contact surface differ. The appearance of the break arcs are taken with the high-speed camera, and the voltage and circuit current at that time were also measured simultaneously. The behavior of the cathode spot region was analyzed from the images of the break arc taken with the high-speed camera. As the results, we were able to confirm that there is characteristic difference in the behavior of the break arc by circuit current when contacts are closed and the radius of curvature. Moreover, when the radius of curvature was large, the tendency for arc duration to become long has been confirmed.