A GIS-based approach for high-level distribution networks expansion planning in normal and contingency operation considering reliability

•GIS-based Mixed-Integer Linear programming (MILP) approach for DNs expansion planning.•Grouping secondary substations in primary substation clusters to obtain a cost-efficient, reliable, DN both in normal and in single contingency operating conditions.•Savings in terms of network extension reduction while maintaining a high level of reliability.•Proposed approach validates with real data. This paper presents a novel methodology for the Distribution Networks expansion planning based on Geographic Information Systems. The proposed methodology combines Delaunay Triangulation with a Mixed-Integer Linear Programming model in a 2-steps approach. Secondary substations are grouped in primary substation clusters, considering both normal and contingency operation. Topological and electrical constraints have to be fulfilled as well as a given level of reliability; the mathematical formulation includes feeder and substation constraints. The proposed methodology is expected to be only the first step of the whole network expansion planning. Hence, it has to be able to give macro information that planners can refine in the following steps of the planning process. A numerical case study on a real network illustrates the effectiveness of the proposed approach for the Distribution Network expansion planning problem.