Detección de descargas parciales en una instalación eléctrica subterránea por medio de procesamiento digital de imágenes térmicas

Abstract

The installation of power cables must be considered a series of factors to ensure good performance in its operation and thus significantly improve the reliability of the system where it is located. During the installation, the use of specific accessories for connection to aerial systems or for connection of equipment is involved, such accessories are known as terminals and splices. According to the statistics, these accessories present 90% of the failures due to problems during their installation or its life, so it is necessary to carry out scheduled studies or monitoring of the operation of electrical installations in order to reduce risks and prevent installation failures. In the present work, an incipient fault detection method is presented, which is based on the analysis of thermographic images of the accessories (splices and terminals) of medium voltage in operation. The objective is to identify the area of a terminal in which there is an incipient failure due to partial discharges, which cannot be observed with a simple thermographic image, but rather requires a digital analysis and processing of the thermographic image in order to identify the point of failure where with digital image processing it is possible to extract information that is not perceived by the naked eye in an image obtained with a thermal imaging camera. The results obtained in the laboratory of faults previously established in an underground electrical installation model are presented.