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Impulse Impedance Measurement Methodology in Space Restricted Locations
2019 International Symposium on Lightning Protection (XV SIPDA), 2019This paper presents the analysis results of field measurements of ground resistance and impulse impedance. First, the Current Derivative Method is presented, whose objective is to obtain the RLF steady-state ground resistance value from the transient impedance curve $Z(t)$.
Adroaldo Raizer +2 more
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Impulse Efficient Optimum Impedance Grounding Electrode Configuration for Lightning Transients
IEEE Transactions on Electromagnetic Compatibility, 2023As the simple grounding electrodes alone may not provide the required low impedance beyond the effective length, a new electrode configuration of optimum impedance is proposed for lightning transients.
Senthil Kumar A +2 more
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Impulse Impedance of Grounding Grids
IEEE Transactions on Power Apparatus and Systems, 1980A method and an empirical formula to calculate the inductance of square grounding grids fed at either centre or one of the corners is presented. Empirical formulae for the effective area and impulse coefficient for centre fed and corner fel square grids are determinel.
B.R. Gupta, B. Thapar
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Impulse Impedance of Buried Ground Wire
IEEE Transactions on Power Apparatus and Systems, 1980The performance of ground electrode under impulse currents must be known if problems concerning lightning protection and transients under ground faults are to be accurately analysed. This paper deals with such performance and establishes a simple analytical expression to determine the impulse impedance of a buried ground wire to a short impulse ...
R. Verma, D. Mukhedkar
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Discussion of Measurement Methods of Impulse Grounding Impedance
2018 34th International Conference on Lightning Protection (ICLP), 2018The grounding device is very important for lightning protection. However, it is difficult to measure the impulse grounding impedance because the impulse generator is cumbersome and dangerous compared with the device for power frequency test. At the same time it is difficult to generate a lightning current with a suitable waveform due to the inductance ...
Bo Zhang +5 more
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Variable Impedance Feed Structure for Impulse Radiating Antenna
2019 International Conference on Electromagnetics in Advanced Applications (ICEAA), 2019We present in this work, an alternative design for the TEM feeding structure of the Impulse Radiating Antenna (IRA). The variation here proposed consists of a set of TEM feeders whose impedance changes as a function of the radial distance measured from the focal point towards the parabolic reflector.
Felix Vega-Stavro +1 more
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Research on impulse impedance measurement for grounding device of transmission tower
2016 IEEE International Conference on High Voltage Engineering and Application (ICHVE), 2016For obtaining impulse impedance characteristics for grounding device of UHV 1000 kV transmission tower, a portable instrument is used as the incident wave source to the grounding device, which stably outputs a 8/20 μs standard lightning current with simultaneous measurement of the response transient voltage.
Si Wen-Rong +4 more
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Impulse impedance of rectangular grounding grids
IEEE Transactions on Power Delivery, 1992In an earlier work B.R. Gupta and B. Thapar (1980) presented the results of investigations and empirical formulae to evaluate the impulse impedance of square grounding grids. In the present work, the authors extend those investigations to the rectangular grounding grids.
B.R. Gupta, V.K. Singh
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Impulse Impedance Tests on Laboratory Model Earth Electrode
2005 Asia-Pacific Conference on Applied Electromagnetics, 2006The investigation was carried out with the purpose of obtaining more information about electric discharges in sandy media. A cylindrical setup was chosen for impulse testing of earth rods to simulate the voltage gradients in the field when lightning propagates to earth rod.
N.A. Idris, H. Ahmad, M.N. Isa
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Impulse impedance tests on laboratory model ground electrodes
IEE Proceedings - Generation, Transmission and Distribution, 2003Impulse impedance of vertical rods embedded in several soil types was determined by laboratory tests under four temperatures and four soil moisture contents with three different waveshapes of the applied impulse voltage. To avoid errors due to current spikes caused by soil ionisation, it is proposed that the impulse impedance be defined as the ratio ...
P. Chowdhuri
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