Transmission system expansion planning with consideration of N-1 security constraints

This paper presents a heuristic method for solving transmission system expansion problems (TSEP) with consideration of N-1 security constraints. The method is divided into two phases. An initial plan is established in the first phase by a search process which is based on a modified simplex method and sensitivity indices. The second phase starts from the initial plan and performs the local search in the defined neighborhood. Additionally, reconstruction of the new lines on the existing right of ways, which is one of the interesting issues of TSEP in the urban area, is taken into account. The proposed method provides very satisfactory results compared with others.