Influence of barriers on the lightning and switching impulse strength of mean air gaps in point/plane arrangements

摘要: The influence of clean and polluted barriers on the breakdown voltage point/plane mean air gaps (30 to 200 cm) under lightning switching voltages is addressed. conditions existence flashover around barrier without surface discharge are determined. It shown that a insulating situated near electrode point, particularly at about 20% gap, leads significant increase in gap. This especially due channel elongation disruptive discharge. A with conductivity higher than 1.6 mu S leads, similar metallic barrier, decrease as compared barrier. simplified model estimate optimal position considering charge densities both its sides, presented. gives results good agreement experimental ones. >