A Hybrid Metaheuristic Method for the Planning of Medium-voltage Power Distribution Systems

The cost pressure on the electric distribution companies has increased after the liberalization of electricity markets. Network efficiency analysis becomes important. Distribution companies carry out network efficiency analysis through benchmarking for the internal controlling. Regulatory authorities use efficiency analysis to check the use of system fees. Today a lot of assets in German distribution systems will reach the end of the useful lifetime within the next twenty years, therefore restructure and renewal measures will be necessary in the coming years. “Green Field” based long-term distribution system planning can provide a reference network for network efficiency analysis and an objective network for the restructure. It is known that the planning problem is a NP-hard combinatorial optimization problem and is normally formulated as a non-linear mixed integer-programming problem. To solve the problem efficiently, we propose a metaheuristic method, which combines guided local search and large neighborhood search. Results of test case show that the proposed hybrid metaheuristic method can provide a high-quality solution of a medium-size problem requiring only some minutes and is therefore especially suitable for efficiency analysis.