Experimental and analytical studies on lightning surge characteristics of a buried bare wire

Abstract

SUMMARYLightning surge analysis is very important from the viewpoint of insulation design of transmission lines and substations. Lightning surge analysis has many parameters, which include lightning surge characteristics of transmission towers, back flashover phenomena at an arcing horn, characteristics of footing resistance, effects of corona wave deformation, characteristics of electromagnetic fields caused by lightning, and other parameters. This paper describes experimental and analytical studies on lightning surge characteristics of a buried bare wire. The measurement of the lightning surge characteristics of the buried bare wire is carried out under various experimental conditions. The experimental parameters controlled in these experiments include earth resistance, length of the buried bare wire, and waveform of the injected current. The measured results are compared with analytical results based on the theoretical study by Sunde. A comparison of the measured results with the analytical results shows good agreement.

Experimental and analytical studies on lightning surge characteristics of ground mesh

“…In such a case that the grounding resistance characteristics of the ground mesh are taken into consideration, the earth conductivity is the important parameter. For buried bare wires, it is known that the earth conductivity has a great effect on the steady-state grounding resistance, while the initial transient GPR is unaffected [15]. However, no evaluation as to whether these characteristics are observed in a ground mesh has been performed.…”

“…The author has already reported that the transient GPR characteristics in the buried bare wires can be reproduced using Sunde's theoretical equations [15]. Based on these theoretical equations, evaluation regarding an analytical model using EMTP is performed.…”

“…Considerable researches have been performed for a long time on the lightning surge characteristics in a ground mesh [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]. In particular, the theoretical analysis by Sunde [1] is well known, and calculation models using the Electro-Magnetic Transients Program (EMTP) based on the theoretical equations by Sunde have been proposed in recent years.…”

Transient response of grounding resistance associated with steady-state value

“…Equation (6) and Table 2 indicate the transient characteristic is determined by the ratio of the surge impedance and the steady-state grounding resistance. The surge impedance of grounding conductors is almost constant and about 100 n [7].…”