Evaluation of impedance parameters in transmission lines

Abstract

A more accurate and flexible grid analysis is achieved through an adaptive and dynamic calculation of line parameters. This is needed for future smart grid implementation. The primary objective of this thesis is to analyze the calculation of transmission line parameters. The impact certain assumptions have on the accuracy of line parameters and fault location algorithms are evaluated. In particular, the impact of the grounded shield wire assumption on the accuracy of fault location algorithms is analyzed. This implies that the impedance of towers be taken into consideration, rather than the simplification of a direct connection of the earth wire to ground. Secondly, the phenomenon of skin-effect is analyzed and evaluated in regards to a more accurate representation of line parameters and a minimization of parameter inaccuracy.