A Fuzzy-Logic Based Evolutionary Multiobjective Approach for Automated Distribution Networks Management

In this paper, a methodology to treat constrained scheduling problems based on the repeated application of a Fuzzy-Logic-based multiobjective algorithm is presented. The application domain is that of automated distribution systems management. In particular, the problem of voltage regulation and power losses minimisation is here considered. The classical formulation of the problem of optimal control of shunt capacitor banks and Under Load Tap Changers, ULTC, located at High Voltage/Medium Voltage (HV/MV) substations has been coupled with the optimal control of tie-switches and capacitor banks on the feeders of a large radially operated meshed distribution system with the aim of attaining minimum power losses and the flattening of the voltage profile. The considered formulation requires the optimisation of two objectives; therefore the use of adequate multiobjective heuristic optimisation methods is needed. The heuristic strategy used for the optimisation is an evolutionary algorithm in which the objectives formulation is based on fuzzy sets theory. After a brief description of the general problem of multiobjective optimisation in automated distribution networks management problems, the most recent papers on the topic are reported and commented. Then, the problem formulation and the solution algorithm are described in detail. Finally, test results on a large distribution system are reported. They demonstrate that the proposed formulation and approach are effective and feasible for finding a good dispatching schedule for the considered system.