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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 Grounding Grids
IEEE Transactions on Power Apparatus and Systems / Technical Operations Committee, 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 ...
Jinjiang He
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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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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 ...
Guangning Wu
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Characterization of human joint impedance during impulsive motion
Journal of Electromyography and Kinesiology, 1993The objective of the present work is to make use of the limited existing information on human joint impedance and to supplement and refine it synthetically, by means of simulation. A modular concept was applied to the construction of a joint model. The basic module was an individual revolute joint which was constrained by four resistive elements.
M, Batman, R, Seliktar
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Reflection of impulses as a method of determining acoustic impedance
The Journal of the Acoustical Society of America, 1984An impulse technique has been developed which allows investigation of the reflection of acoustic transients at different angles from an impedance boundary. From measurements of the direct and reflected impulses, the complex surface impedance has been calculated from the ratio of the corresponding Fourier components.
A. J. Cramond, C. G. Don
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Issues Concerning Determination of Impulse Voltage, Current, and Impedance
IEEE Electromagnetic Compatibility Magazine, 2021The paper deals with satisfying the quasi-stationarity (or quasi-static) condition in studies of impulse quantities. The validity of the definition of voltage, current, and immittance is discussed. Examples are given regarding the electromagnetic compatibility issues when the quasi-stationarity condition is not met, thus the basic electric circuit ...
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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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