触头弧根瞬时电流密度的测量

电弧对触头表面的功率输入是影响触头侵蚀量的决定因素。为了深入了解电弧弧根功率输入过程,从而对侵蚀过程进行合理建模,有必要对触头弧根瞬时电流密度进行测量。本文对AgMeO材料的圆柱形触头在200～1800A峰值电流范围内,进行了半波正弦电流的开断试验,采用高速摄影技术和扫描电镜(SEM)微观照片两种方法测量,并分析了弧根直径及弧根瞬时电流密度与电流的关系,还对比了两种测试方法的差异。

Measurevment of Instantaneous Current Density in Arc Root

The energy input from the arc to the contact surface is a decisive factor on erosion of contact materials. In order to improve the modelling of the erosion process, it is imperative to measure the instantaneous current density on arc root. Breaking experiments with cylindrical AgMeO contacts were carried out in the current range from 200 to 1800A peak. Arc root diameters and apparent current densities were evaluated from high speed camera observations and SEM micrographs.