Research on dynamic characteristics of arc under electrode relative motion

Abstract

The relative motion of the electrodes is a typical feature of sliding electrical contact systems. The system fault caused by the arc is the key problem that restricts the service life of the sliding electrical contact system. In this paper, an arcing experimental platform that can accurately control the relative speed and distance of electrodes is built, and the influence of different electrode speeds and electrode distances on arc motion characteristics is explored. It is found that there are three different modes of arc root motion: single arc root motion mode, single and double arc roots alternating motion mode, and multiple arc roots motion mode. The physical process and influence mechanism of different arc root motion modes are further studied, and the corresponding relationship between arc root motion modes and electrode speed is revealed. In addition, to further explore the distribution characteristics of arc temperature and its influencing factors, an arc magnetohydrodynamic model under the relative motion of electrodes is established, and the variation law of arc temperature under the effect of different electrode speeds and electrode distances is summarized. Finally, the influence mechanism of electrode speed and electrode distance on arc temperature, arc root distance, and arc root speed is clarified. The research results enrich the research system of arc dynamic characteristics in the field of sliding electrical contact, and provide theoretical support for restraining arc erosion and improving the service life of the sliding electrical contact system.