Open AccessAn improved method for expressing the transient ground resistance of overhead transmission lines by exponential polynomial
Author(s) -
Liu Xin,
Wang Litong,
Yang Jiawei,
Yue Huiqing
Publication year - 2017
Publication title -
iet generation, transmission and distribution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.92
H-Index - 110
eISSN - 1751-8695
pISSN - 1751-8687
DOI - 10.1049/iet-gtd.2017.0215
Subject(s) - electric power transmission , transmission line , overhead (engineering) , exponential function , polynomial , transient (computer programming) , conductor , line (geometry) , mathematical analysis , convolution (computer science) , overhead line , mathematics , algorithm , computer science , electronic engineering , geometry , engineering , electrical engineering , telecommunications , operating system , machine learning , artificial neural network
In this study, a method is proposed for expressing the transient ground resistance of the overhead transmission lines (TLs) by the exponential polynomial. The relation of the poles due to the rational approximation of the ground resistance between the ground conductivity, permittivity and the line geometry is fully discussed. A concept of ‘normalise poles’ is introduced, which makes it very easy to evaluate the poles according to any ground conductivity, permittivity and line geometrical geometry. A new and easily programmed method is achieved which can overcome the uncertain error caused by the conventional vector fitting method when approximating the ground resistance. Based on this method, a recursive convolution can be achieved for analysing the multi‐conductor TLs system, so good efficiency can be obtained. Several examples are provided to demonstrate the validation of the proposed method for evaluating the transient ground resistance with different ground parameters and line geometry, and an application on calculating the lightning induced voltages of the overhead TLs system is also provided.