THERMOFLUCTUATION THEORY OF DESTRUCTION AND EVALUATION DURABILITY OF ELECTRICAL INSULATION OF SPE CABLES

Abstract

The article is devoted to research on the creation of a method for assessing the durability of
the main insulation of power cable lines based on the thermofluctuation theory of destruction of solids.
The features of breakdown development in homogeneous and inhomogeneous dielectrics are
considered. The problematic issues of insulating materials of power cable systems (PCS) are considered
on the basis of the development and development of non-destructive testing methods. The main
components that destroy the insulation of the PCS are installed. The thermofluctuation theory of
destruction and the evaluation of the durability of electrical insulation of power cables are described.
An analytical method is proposed for evaluating the processes of cellulose oxidation with the determination
of the most probable. The proposed approach to identifying the main processes of insulation
destruction allows us to present in more detail the prerequisites for the development of partial discharges
(PD) in isolation and to determine measures to minimize the processes leading to the destruction
of PCS insulation. The results of experiments on the study of the service life of the insulating
material of aged ends of a power cable in a thermal cabinet, to determine the aging criteria, are
presented. The experimental data are interpreted from the standpoint of the thermofluctuation theory.
The dependence of the increase in the temperature difference ΔT on the degree of wear of the electrical
insulating properties of the material is revealed and investigated, which makes it possible to predict
its resource. The thermofluctuation theory of the destruction of insulating materials caused by
the thermofluctuation rupture of chemical bonds and the evaluation of the durability of electrical
insulation of cables made of cross-linked polyethylene are considered. It is shown that, in order to
calculate the average energy of the monomeric link of various polymer materials, it is necessary to
know: the chemical formula of the monomeric link and the values of the binding energies. In the
work, the time before the breakdown of the main insulation of the PCS was determined under the
action of temperature. The model can be used in devices and systems for continuous diagnosis of
power cables according to temperature conditions.