Transmission Lines Impedance Fitting Using Analytical Impedance Equation and Frequency Response Analysis

Abstract

Rational function approximation is commonly used to fit the transmission line impedance over a wide frequency range. Nevertheless, it is computationally costly and challenging to implement in practical applications due to the high number of approximations required to fit the impedance curve for the high-frequency range. Therefore, a novel fitting method of multiconductor transmission line (MTL) based on the analytical impedance equation of a transmission line using the impedance frequency response measurement is presented in this paper. The proposed fitting method is a function of the transmission line length since it is based on the analytical impedance equation of a finite transmission line. Furthermore, the proposed model uses a constant set of equations and calculated parameters to fit the impedance frequency response for a wide range of frequencies. Moreover, the proposed model parameters are calculated using derived resonance equations and the impedance frequency response measurement. In addition, an algorithm is developed to further fit the proposed model to the impedance frequency response measurement of the transmission line. MTL impedance frequency response is measured using a real-time digital simulator (RTDS). To ensure the accuracy of the proposed model, a comparison between the proposed model and vector fitting (VF) is presented.

Modeling and Simulation of Coupled Power Transmission Line: A Systematic Approach

“…Lumped model is studied by Girona-Badia et al [15] who compared the accuracy and computation time of different models of synchronous generators, transmission lines, converters, wind turbines, and photovoltaic (PV) power plants using simulations of load connection, short circuits, generator and line disconnection. Medved' et al [16] studied the current effect on temperature and asserted that transmission current of 3000A could raised temperature to 80 0 C. Koksal et al [17]; Alharbi et al [18] developed a mathematical model of time and space dependent shunt parameters and time dependent series parameters in power transmission lines. For time-variable boundary solutions, first-order, second-order, and third-order difference techniques were used.…”