Sistema de avaliação da confiabilidade dielétrica de cabos isolados de alta tensão baseado em descarga parcial como módulo de digital shadow

Abstract

The evaluation of the dielectric reliability of medium and high voltage power cables is a very important procedure for the prevention of failures and operational continuity in industrial environments. Insulation degradation, driven by mechanisms such as thermal aging, moisture penetration, and localized defects, manifests itself early through partial discharges, whose systematic monitoring and interpretation make it possible to anticipate critical conditions before asset failure. In this context, the present work proposes a methodology for evaluating the dielectric reliability of medium and high voltage cables from the monitoring of partial discharges, designed to operate as the dielectric evaluation module within a Digital Shadow architecture aimed at the management of electrical assets. The methodology is organized in a sequential pipeline of five steps: (i) signal acquisition by means of sensors (either in offline or online regimes), (ii) separation of signals from partial noise discharges, by hierarchical clustering by Ward's method, (iii) evaluation of dielectric severity by fuzzy logic, (iv) estimation of the cable state in the Weibull reliability curve, through a degradation model and (v) weighting adjustments by the signal quality index and final evaluation by condition ranges based on IEEE Std 400.3 and CIGRE TB 841 guidelines. These methodological procedures, when added together, aim to qualify the reliability of the cable based on its discharge signals. This set must work within the concept of "Digital Shadow", receiving data from the sensors installed in the physical world, processing it and producing, at its end (usually in a cloud system) a coherent physical indication of the state of the (insulation) of the cable under monitoring.