Effect of Temperature on the Breakdown Probability of Liquid Dielectrics

The effect of temperature on the probability of breakdown of mineral oil usinig power-frequency voltages has been investigated. Results of the breakdown probability are plotted on a Weibull distribuion and fit well in two straight lines intersecting at a certain transition point. This transition corresponds to a breakdown probability and a breakdown voltage which are temperat ure dependent. Results suggest that different breakdown initiating mechanisms may be simultaneously active, and the dominance of one of them on the other is responsible for the observed transition in the breakdown probability characteristics.