Evolution Strategies to Transmission Expansion Planning Considering Unreliability Costs

This paper presents a new methodology to solve transmission expansion planning (TEP) problems based on Evolution Strategies (ES), but other heuristics are also used to assist the search process. The TEP problem includes the search for the least cost solution, bearing in mind investments and interruption costs. Unreliability costs are considered through the index LOLC ? Loss of Load Cost. Moreover, the dynamic nature of the TEP is accounted for by the proposed methodology. Case studies on a small test and on a real sub-transmission network (CEMIG Company, Brazil) are presented and discussed.