A fuzzy-based algorithm for shunt capacitor planning in a distorted power system

This paper presents a fuzzy-based algorithm for the placement and sizing of shunt capacitor banks in a harmonics-polluted distribution system. In the problem the objective function is the total system power loss and the capacitor installation cost, while the constraints are the rms voltage, the individual and total harmonic voltage distortion limits at each bus, and the limit of the available capacitor units to be placed. In the study the power loss index associated with each bus, the rms voltage, the individual and total harmonic voltage distortions at each bus, and the capacitor site suitability are modeled as fuzzy membership functions. A useful solution algorithm is then proposed to find the most suitable capacitor locations and corresponding sizes for an actual distribution network. Results obtained by the proposed approach are compared with those obtained by a traditional nonlinear programming method and a maximum sensitivity-based approach. Numerical experiences show that the proposed method yields favorable results for the capacitor planning problem.