Upgrade and refurbishment methodologies apply to Gibraltar Electric Authority’s power distribution system project

Abstract

This paper describes the choice in the project methodologies and taken to integrate the refurbishment and upgrades of the Gibraltar Electricity Authority HV grid and substations with clear limitations in the possible impacts.GEA has decide to strongly invest on refurbishment, replacement and upgrade of the actual Distribution grid to improve it efficiency and reliability.As introduction a brief description of the original GEA grid and the main project’s constraints and how this has influence the grid architecture design and the project management choices.In the second part, the authors present how the optimized replacement plan for the various substations and the implementation strategy has been finalized using grid simulation tools and evaluating each choice impact on the global project and future stages. The integration of the refurbished and new parts is detailed and how these new architectures (loop management, substation design, adaptive automation schemes, ...) and features (protection functions and settings, , partial Generation management, ...) and architectures have impacted the existing parts is also detailed with the respect of the continuity of service and the minimization of the environmental impact.The third part presents the methodologies of Tests in the factories and on Site and explain the capabilities given to GEA to define the priority of evolutions based on GEA grid constraints and requirements.As conclusion, some GEA project key features and lessons are briefly explored and described with some potential impact on the future GEA grid.