Impulse Breakdown and Power-Frequency Partial Discharge Inception Voltages of Insulating Liquids

Test procedures used in power-frequency and impulse tests on dielectric liquids are discussed in the paper, The voltage stress relative to a given test procedure is represented as a combination of a certain number of "elementmentary stresses". Then, on the basis of rather simple theoretical consideraticons, the partial discharge inception (or breakdown) probability related to the test procedure is expressed as a function of the probability associated with the "elementary stress". In this way, the effects of the test procedure on the results are made evident and new possibilities for analysis of dielectric test results are open. Partial discharge and impulse test results are reported and analyzed following this approach.