PLACEMENT AND SIZING OF PASSIVE FILTERS IN POWER SYSTEMS

Abstract

With wide spread proliferation of non-linear loads significant amount of harmonic currents are inserted into the power systems. Harmonic currents not only disturb load that are sensitive to wave form distortion, but also cause many undesirable effects on power system elements. As a result system wide solutions to harmonics become a growing concern. With keeping this in mind, harmonic load flow using current injection method is discussed here .a diode bridge is used to show the effect of harmonic. Further harmonic elimination using passive filter for third the harmonic is presented. In continuation with passive filter planning, a method has been proposed and analyzed for determining Optimal or near-optimal locations and sizes of single-tuned passive harmonic filters using existing capacitor busses in a power systems .And also at other buses. The objective of the harmonic filter planning is to control the system-wide voltage distortion, while individual/total harmonic voltage distortion limits at each network bus and the filter component bounds are considered as constraints. The solution methodology consists of two phases. In first phase an unconstrained optimization problem for placement of the filters based on sensitivity analysis. Subsequently used in the next phase, a constrained problem is formulated and is solved by function minimization. Test results show that the method is effective, and suitable for passive filter planning in power systems.