TY  - JOUR
T1  - Field Problems of Distance Relays with Combined Single/Double
Circuit Transmission Lines
AU - A. Kawady, Tamer AU - M.A. Sowilam, Gamal AU - A. Shalwala, Raed 
JO  - Journal of Engineering and Applied Sciences
VL  - 15
IS  - 2
SP  - 415
EP  - 420
PY  - 2020
DA  - 2001/08/19
SN  - 1816-949x
DO  - jeasci.2020.415.420
UR  - https://makhillpublications.co/view-article.php?doi=jeasci.2020.415.420
KW  - Parallel lines
KW  -distance relays
KW  -frequency dependent parameters
KW  -EMTP
KW  -MATLAB
KW  -networks
AB  - Parallel transmission lines are characterized with a significant increase in the mutual coupling effects
among the different phases of the coupled line segments raising remarkable errors for impedance-based
protection equipment in particular. Owing to these situations, the total line impedance of each phase of the
associated line may significantly change resulting from the mutually reflected impedances from the other
phases. Thus, double line segments, when combined to single circuit ones, can significantly lead to have a
deviated measured fault impedance from those parameters that are adjusted during the relaying setting stage.
This may, accordingly, cause remarkable errors for distance protection algorithms in the field leading to
unnecessary tripping or delayed fault clearing. In this study, the impact of the combination of single and double
overhead line segments on the performance of distance relaying function is thoroughly investigated. This
investigation is carried out using the Electro-Magnetic Transient Program (EMTP) using distributed parameter
line modeling. The accuracy of the developed simulation is validated as compared with a recorded fault case
for a 400 kV combined single/double line from the field. This corroborated the correctness and the accuracy
of the constructed model. The relay enabled functions and setting are collected and realized in the MATLAB
environment. This research is essential for visualizing the core of the problems of these transmission networks
with distance function and can consequently help to realize a practical and reliable distance relaying for such
lines.
ER  -