A posteriori decision analysis based on Resonance Index and NSGA-II applied to the capacitor banks placement problem

This paper proposes a new methodology based on the use of Resonance Index (RI) analysis as a posteriori decision-making procedure to check solutions of the optimization algorithm NSGA-II against resonance, when applied to the capacitor banks placement problem in radial distribution systems. Most of existing methodologies approach harmonic resonance in the referred problem through the inclusion of constraints in the optimization procedure with respect to the harmonic distortion indexes THD and IHD. However, monitoring only these two parameters is not sufficient to identify specific problems on capacitor banks due to harmonic resonance. To demonstrate this point, a RI analysis using the resonant chart was performed considering a 34-bus radial system. Also, the proposed a posteriori analysis is compared with the one that includes directly RI as a constraint in the optimization procedure, demonstrating that the proposed approach has a better performance with respect to computational time.