A New Method for Sub-Transmission Substation Expansion Planning via a Fuzzy Weighted Approach Applied to the Electrical and Geographical Properties of the Under Study Network

This paper presents a new solution approach to solve the sub-transmission substation expansion planning (SSEP) within large distribution networks. To do so, the SSEP is investigated based on a probability matrix which contains geographical and electrical features of the studied distribution network. The developed algorithm includes different electrical constraints and considers all prevalent cost indices. Possibility of supplying any of loads from each substation is calculated through the proposed method using membership matrix, modifying center of gravity theory and providing other heuristic approaches. Complexity of the problem is substantially reduced by means of the calculated probability matrix, and optimization process is carried out based on the introduced probability matrix.Detailed numerical results and comparisons presented in the paper show that the proposed approach could noticeably improve the quality of problem solutions and can be used as an effective tool for SSEP within actual distribution networks.