Experimental Investigation of the Process of Arc Propagation over an Ice Surface

In this paper, some of the characteristics of an arc propagating over an ice-covered insulator surface were investigated. Special attention was paid to the arc root and channel characteristics. All experiments were performed on a simplified physical model to simulate real ice-covered insulators. From the obtained results, based on a set of time-resolved measurements of a surface discharge, some important characteristics, namely arc foot geometry and channel diameter were observed. Possible mechanisms controlling these variations are discussed. An empirical model, accounting for arc propagation pattern on an ice surface, is proposed. The paper contains a substantial amount of new material with a view of closing some major gaps in the present state of knowledge of ice surface flashover.