Aplicação do método de Murray na pré-localização de falhas em cabos isolados em Redes de Média Tensão

Abstract

With the increase in the number of solar and wind farms, there has also been an increase in their constituent infrastructure, such as the underground medium-voltage grid. Due to the higher reliability of this type of network and the nature of the farm, the installation of overhead lines becomes unfeasible, as they would lead to a decrease in the farm's production. However, underground grids present their own challenges, as locating faults along their path is significantly more difficult. In use for over a century, the Murray bridge method is one of the most widespread methods for locating faults in underground sections. However, new modern methods have emerged in recent decades, highlighting the limitations of the Murray method. To perform a comparative analysis, the methodology used consisted of a review of the constitution of insulated cables and the current technical standards. Following this, a critical analysis of the Murray method was conducted, comparing it to modern methods to verify its relevance in the current scenario. Additionally, the accuracy of the method was demonstrated through a practical example. At the end of the thesis, it is concluded that, despite its classic limitations, technological modernizations ensure that the Murray method remains a relevant and safe tool in the arsenal of fault location for power systems.