Multiobjective Optimization and Fuzzy Logic Applied to Planning of the Volt/Var Problem in Distributions Systems

This paper deals with integrated voltage and reactive power control (volt/var) for radial distribution feeders in planning issues, by means of the application of automatic voltage regulators (AVRs) banks and capacitors. A multiobjective genetic algorithm (SPEA2) improved using fuzzy logic is presented to solve the volt/var problem, since it is a combinatorial multiobjective optimization problem. The expert knowledge is taken into account via fuzzy logic in order to reduce the search space using voltage regulators in standard units. According to the multiobjective optimization fundamentals, an optimal solution ensemble is obtained, which concomitantly represents the solutions to both objectives, in such way that the operational restrictions of systems are satisfied. The algorithm is evaluated for a known 69-bus feeder in the literature of the subject. The obtained results demonstrate that the proposed method provides good concordance between the obtained solution and the Pareto front.