Influence of the Insulation Defects Size on the Value of the Wire Capacitance

Abstract

The study focuses on detection of defects in the single-core electrical wire insulation by changing the linear capacity of the electric wire. Numerical simulation was performed to create defects that are difficult to implement in practice. In the study, models of the following defects were created: local thinning of the wire insulation, eccentricity, foreign inclusion in the wire insulation. During the study, the depth and length of the ‘local thinning’ defect in the wire insulation, the shift of the core center relative to wire the center, length and thickness of the ‘foreign inclusion’ defect were varied. As a result, absolute and relative values of the geometric dimensions of the defects that cause a significant change in the wire capacitance are revealed. A significant deviation of the capacitance is taken at the level of 5% deviation from the nominal value of the capacitance of a defect-free wire in accordance with the requirements of normative and technical documentation and the accuracy of device for in-process testing of the wire capacitance. The paper reports the results of the initial study. Further research is required to increase the reliability of the models used.