Aumento da fiabilidade através da reconfiguração da linha DL14 de 66 KV da EDM – divisão de transporte sul

Abstract

In electric power transmission systems, service continuity and operational flexibility are fundamental requirements to ensure supply reliability. The 66 kV DL14 transmission line, which connects the Matola 275 Substation to the Boane Substation and supplies the LIMAK and Matola Rio substations through T-branch derivations, presents significant operational limitations. Periodic maintenance activities at the Matola 275 and Boane substations, as well as fault occurrences along the line, require the complete shutdown of the line, affecting service availability and operational safety. In this context, the present work proposes the reconfiguration of the existing T-branch points into an Input and Output configuration, aiming to improve selectivity and operational flexibility. The solution includes the technical sizing of switching panels and protection equipment suitable for the 66 kV voltage level, as well as the verification of rated currents, short-circuit levels and protection coordination according to applicable standards. The adopted methodology was based on bibliographic research, analysis of the technical data provided by EDM, assessment of the existing configuration, and the execution of electrical sizing calculations, including a comparative evaluation between the current and the proposed arrangements. The new configuration allows the isolation of only the affected span during maintenance interventions, avoiding total shutdowns of the DL14 line and reducing the impact on the supplied substations. It is concluded that the proposed solution increases the reliability and operational flexibility of the DL14 line, enabling maintenance activities without complete disconnection and contributing to improved performance of the transmission network in the Southern Region of Mozambique.