Optimal Maintenance Scheduling of Transmission Assets in the Brazilian Electric System

An electric utility has as an objective to guarantee the continuity and quality of the service provided. In order to enforce an increase in the quality of service, the ANEEL (Portuguese for The Brazilian National Electric Energy Agency) introduced penalties in contracts with public electricity transmission utilities in case transmission facilities are taken out of service due to accidents, failures or scheduled maintenance. Traditional maintenance approaches to electric power transmission systems are based on actions taken periodically. Although these approaches aim to improve the performance of these systems, usually they do not accurately assess the impact of maintenance actions on their reliability related to the resources employed, as well as the resulting legal penalties. This paper proposes an approach for addressing this problem based on reliability/cost to find the best strategies for performing maintenance on electric power transmission equipment (assets), with a mathematical model that provides a feasible maintenance calendar while respecting the constraints of the electrical system operation. The proposed method consists of a combination of a constructive heuristic with dynamic programming, to find the best solutions for a given planning horizon.