Optimal capacitor banks placement in distribution grids using NSGA II and Harmonic Resonance Chart

This paper proposes a procedure to obtain optimal capacitor banks placement in distribution grids that incorporates a resonance analysis to the resulting Pareto Front optimal solutions, to guarantee that the adopted solution does not cause dangerous voltage harmonic resonance for the electric system. A multiobjective optimization procedure based on the Non-Dominated Sorting Genetic Algorithm II (NSGA-II) technique is used to solve the problem of optimal placement and sizing of capacitor banks, considering voltage magnitude and total harmonic distortion constraints, producing a Pareto Front of optimal solutions. The resonance analysis is accomplished by using the harmonic resonance chart, as proposed in [1] to identify if the Pareto or other viable solutions can cause dangerous harmonic resonance. To test and validate the proposed methodology, a 34-bus radial distribution network was used considering typical non-linear loads as harmonic current sources. The obtained results were very effective which indicate the proposed procedure is very promising in obtaining solutions for this type of problem.