Propagation characteristics of impulse creepage discharge in a parallel‐plane gap with a protruding point in transformer oil

The propagation characteristics of the creepage discharge in a parallel-plane electrode gap with a protruding point in transformer oil are observed and investigated in detail under an impulse voltage application by using a high-speed schlieren optical technique and an LED current measurement system. Streamer-like density changes appeared from the protruding point tip of one high-voltage plane electrode and propagated to the other grounded plane electrode. In the present paper, the effect of the arrangement of a barrier insulator and the electric field direction on the propagation of the creepage discharge is discussed. © 1998 Scripta Technica, Electr Eng Jpn, 124(2): 1–7, 1998