Implementation of the Extended Insulation Parameters Method for Physical Interpretation of Diagnostic Measurement Data

Abstract

The objective of this paper is to present a novel method to estimate the remaining lifetime of paper insulated lead covered (PILC) cables. It is based on a physical basis and will respect 25 different known diagnostic values. Usually, only certain single parameters, like the dissipation factor, have been used to estimate the condition of the cables up to now. By considering the global insulation system of the PILC cables, a more precise estimation of the ageing factor can be given. The extended insulation parameters (EIP) method involves the application of physical and measurable parameters, such as time constants, base capacitance, conductivity losses, polarization capacitance and losses, etc. These values are measured for new and aged cables and weighted according to their influence on the asset degeneration. Detailed information about the EIP method is given in the article, explaining how the individual parameters affect the degeneration. It also describes the basic principles of the lifetime estimation methods applied for the considered PILC cables.