Results 151 to 160 of about 45,205 (189)
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The Tapered Impedance Half-Impulse Radiating Antenna
IEEE Transactions on Antennas and Propagation, 2021In this article, we introduce the tapered impedance half-impulse radiating antenna (TI-HIRA). This innovative version of the HIRA allows the direct connection of COTS, $50~\Omega $ generators to the antenna, without requiring external transformers and without using the large, blocking, plates that would be required in the traditional constant ...
Felix Vega +2 more
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Impulse Impedance Measurements of Lightning Protection Earthings
2019 IEEE PES GTD Grand International Conference and Exposition Asia (GTD Asia), 2019Lightning protection earthing systems should be tested at currents with time parameters similar to those of lightnings. A method and definition of a measured value of impulse impedance are introduced. The impulse impedance was determined by a quotient of voltage drop on the tested earthing to a value of current in measure circuit. The usefulness of the
T. Horchue +3 more
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Measurement of Impulse Grounding Impedance in Frequency Domain
2010 International Conference on Intelligent System Design and Engineering Application, 2010Impulse grounding impedance cannot be described as an absolute index, because it depends on the characteristic of the impulse current waveform, soil structure type and grounding system configuration, etc. This paper presents a test system to measure the impulse grounding impedance directly in time domain, moreover, calculated and defined in frequency ...
Wu Guangning
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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 ...
Jinjiang He
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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 $Z(t)$.
A Raizer
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A reduced-scale experimental study of tower impulse grounding impedance
2017 1st International Conference on Electrical Materials and Power Equipment (ICEMPE), 2017Lightning withstand level of the transmission line is directly affected by the value of the tower impulse grounding impedance. While it's difficult to obtain the tower impulse grounding impedance accurately as its nonlinearity under impulse current. Therefore the study of the tower impulse grounding impedance characteristics is significant to lightning
Jiangtao Li, Hui Cao, Zheng Zhao
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Impulse Impedance and Effective Area of Grounding Grids
IEEE Transactions on Power Delivery, 2021High values and uneven distribution of the transient ground potential rise (TGPR) at grounding grid conductors in cases of lightning can disrupt the system safety and reliability. To assess the transient performance of grounding grids under lightning currents, a parametric analysis was performed with a computer simulation of 13,978 cases of time-domain
Leonid Grcev, Blagoja Markovski
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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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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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Online Monitoring of the Cable Insulation State Based on the Impulse Impedance Spectrum
IEEE Transactions on Instrumentation and MeasurementPengfei Meng, Tengfei Li, Kai Zhou
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