دانلود رایگان مقاله isi افزایش ولتاژ دراثر صاعقه و رعد و برق Surge voltages and currents lightning

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خلاصه ای از مقاله افزایش ولتاژ در اثر صاعقه و رعد و برق:
Surge voltages and currents into a customer due to nearby lightning



abstract
This paper presents experimental results of lightning surges incoming into a customer due to lightning to an antenna of the customer, a pole and a ground nearby the customer, and   briefly discusses lightning current distribution in the customer, a distribution line and a telephone line. Based on experimental results, modeling of each component is explained, and EMTP simulations are carried out. The ground voltage rise is represented by a mutual resistance between grounding electrodes. EMTP simulation results have been observed to agree qualitatively with the measured results, and it becomes possible to   investigate lightning surges and current distribution in a customer by an EMTP simulation. © 2008 Elsevier B.V. All rights reserved.

1. Introduction
Lightning overvoltages are important not only from the viewpoint
of insulation coordination of transmission systems but also
from the viewpoint of protection of customers’ equipments and
telecommunication systems. A number of disturbances of home
appliances due to the lightning have been informed [1–5]. In a survey
of the disturbances in a utility in Japan, nearly 100 disturbances
per year are found to be caused by the lightning.
This paper investigates experimentally an incoming path of
a lightning surge into a customer due to lightning nearby the
customer [6,7]. There exist four incoming paths: (1) low-voltage
distribution line (feeder) through a distribution pole, (2) telephone
line, (3) customer’s TV antenna and (4) grounding electrode of
a customer’s electrical equipment. A lightning strike to a distribution
line and an induced lightning voltage to the distribution
line result in the path (1). Similarly a lightning strike to a telephone
line and an induced lightning voltage result in the path
(2), and the same is applied to the path (3). A lightning strike to
a ground, a wood or a distribution pole nearby a customer results
in a ground potential rise (GPR) due to a lightning current flowing
into the ground [8,9]. The current causes a potential rise to a
grounding electrode of a customer’s equipment which is the path
(4).
Based on the measured results, modeling of electrical elements
related to the above paths for a lightning surge simulations are
developed, and EMTP simulations are carried out by the model. The
simulation results are compared with the measured results and the
accuracy of the modeling method is discussed.
2. Experiment of incoming surge into house
2.1. Experimental conditions
Kansai Electric Power Co. (KEPCO) has carried out a number
of experiments to investigate lightning currents flowing into a
house [6,7]. An impulse current representing a lightning current
is injected into an antenna, a distribution pole and a ground from
an impulse current generator (IG, maximum voltage 3 MV, maximum
current 40 kA). Fig. 1 illustrates an experimental setup. An
impulse current from 500 to 5000A is applied to:
(a) an antenna: Fig. 1(A);
(b) a distribution pole: Fig. 1(B);
(c) a structure nearby a house: Fig. 1(C);
(d) a messenger wire of a telephone line: Fig. 1(D).