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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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Measurement and Analysis of Impulse Grounding Impedance for UHV Transmission Tower
2018 IEEE International Conference on High Voltage Engineering and Application (ICHVE), 2018In this paper, application of a portable instrument to gain impulse grounding impedance (IGI) characteristics for grounding device (GD) of ultra-high-voltage (UHV) 1000 kV transmission towers is introduced. The test currents of 8/20 $\mu$ s and 10/350 $\mu$ s were chosen as the injection signal sources to the grounding device respectively, while the ...
W. R. Si +4 more
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Measurement of transfer impedance under impulse conditions
1987The measurement of the transfer impedance of a screened coaxial cable using a low-power sinusoidal current has the disadvantage that the saturation effects which occur in the ferromagnetic screen are not reproduced. The authors describe a method for measuring the impedance using a source of current pulses with a magnitude of a few hundred amperes.
Blech, P., Dijamatovic, Y., Ianoz, M.
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Fundamental Considerations and Impluse Impedance of Grounding Grids
IEEE Transactions on Power Apparatus and Systems, 1981The impulse impedance of a grounding grid must be known for determining its performance while discharging impulse currents to ground if problems concerning lightning protection and transients under ground faults are to be accurately analysed. This paper out-lines the basic concepts required for this study, analyses the equivalent circuit ,21]of a ...
R. Verma, D. Mukhedkar
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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 ...
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The impulse grounding impedance computation in HVDC transmission line tower
2013 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC), 2013Electromagnetic field and circuit theory combined is applied to calculate the impulse grounding impedance in HVDC transmission line towers in this paper. The mutual inductance of conductor segments are taken into account. At the same time, the images of the self resistance and mutual inductance are considered for the different medium (soil and air ...
Li Tian-wei, Xiang Yang, Zhao Yu-ming
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Research on Field Test of Impulse Grounding Impedance for Small Substation
2018 International Conference on Smart Grid and Electrical Automation (ICSGEA), 2018In this paper, application of a portable instrument to obtain impulse grounding impedance (IGI) characteristics for grounding grid of small substation is introduced. The test currents of 8/20 µs, 10/350 µs and 30/80 µs were chosen as the injection signal sources to the grounding grid respectively with simultaneous measurement of the response ...
Si Wen-Rong +5 more
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Achievements in the Measurement of Tower-footing Impulse Impedance of Transmission Lines
2018 34th International Conference on Lightning Protection (ICLP), 2018This paper presents results obtained from field measurements of tower-footing impulse impedance carried out in real transmission lines. Tests were performed using an impulsive voltage generator, measuring the ground potential rise and the impressed current to determine the impulsive grounding impedance.
Silverio Visacro +2 more
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Calculation of the voltage on earth impedance caused by lightning impulse current
Archiv für Elektrotechnik, 1988In case of lightning stroke into a tower the impulse current behaviour of the ground is of great importance. A simplified model for estimation the lightning performance of grounding electrodes has been evaluated. Based on field theory the inductive character of the earthing impedance is explained.
G. Tevan, K. Petri
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2023 IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting (USNC-URSI), 2023
Fernando Albarracin +3 more
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Fernando Albarracin +3 more
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