Streamer inception and propagation models for designing air insulated power devices

This paper focuses on simulation based dielectric design rules of air insulated medium voltage power equipment. After a brief overview on the classical dielectric designing procedure, we propose possible new concepts and present first experimental results on streamer inception and propagation affected by dielectric surfaces. For evaluation of the inception voltage we achieved a good experimental agreement for a path between electrodes where the tangential component of the electric (background) field approaches the maximum value. This new calculation method differs from the traditional one based on evaluation along field lines. The streamer propagation models investigated in this paper can be used for a prediction whether streamers can reach the opposite electrode.