Evaluation of Lightning-Induced Voltage on Overhead Lines With Nonlinear Load Using the Scattering Theory

2012 ◽  
Vol 27 (1) ◽  
pp. 317-324 ◽  
Author(s):  
Hamed Janani ◽  
Rouzbeh Moini ◽  
Seyed Hossein H. Sadeghi
Keyword(s):  
Scattering Theory ◽  
Induced Voltage ◽  
Nonlinear Load ◽  
Overhead Lines

scholarly journals Full-Wave Analysis of Field-to-Line Coupling Effects Using 1D FDTD Method under Exciting Source with Different Bandwidths

2014 ◽  
Vol 2014 ◽  
pp. 1-8
Author(s):  
Qi Zhang ◽  
Bihua Zhou ◽  
Jianbao Wang ◽  
Cheng Gao
Keyword(s):  
Fdtd Method ◽  
Line Length ◽  
Maximum Energy ◽  
Stratified Medium ◽  
Induced Voltage ◽  
Coupling Effects ◽  
Absorbing Boundary ◽  
Bell Laboratory ◽  
Overhead Lines ◽  
Line Coupling

With the aim to analyze field-to-line coupling effects based on energy spectrum, parallel finite-difference time-domain (FDTD) method is applied to calculate the induced voltage on overhead lines under high-power electromagnetic (HPEM) environment. Firstly, the energy distribution laws of HEMP (IEC 61000-2-9), HEMP (Bell Laboratory), HEMP (Paulino et al., 2010), and LEMP (IEC61000-4-5) are given. Due to the air-earth stratified medium, both the absorbing boundary and the connecting boundary applied to scattering by finite-length objects are separately set in aerial and underground parts. Moreover, the influence of line length on induced voltage is analyzed and discussed. The results indicate that the half-peak width is wider with the increase of the line length. But the steepness of induced voltage on the overhead line is invariable. There is no further increase in the peak of induced voltage especially when the line length increases to be equivalent to the wavelength of the frequency bands with the maximum energy.

About safety when working on overhead lines under induced voltage to reduce electrical injuries

2020 ◽  
pp. 822-822
Author(s):  
O. S. Shcherbacheva ◽  
I. V. Korolev ◽  
D. A. Burdyukov
Keyword(s):  
Induced Voltage ◽  
Overhead Lines ◽  
Electrical Injuries

The basic requirements to ensure the safety of work under induced voltage are systematized, as well as recommendations to reduce electrical injuries when performing work on disconnected overhead lines under induced voltage are given

scholarly journals Determination of Electromagnetic Influence of 25 kV AC Electric Traction Network on 10 kV High-Voltage Overhead Line

2021 ◽  
Vol 2096 (1) ◽  
pp. 012078
Author(s):  
O V Zalesova
Keyword(s):  
High Voltage ◽  
Short Circuit ◽  
Electrical Equipment ◽  
Point Of View ◽  
Overhead Line ◽  
Induced Voltage ◽  
Operating Personnel ◽  
Overhead Lines ◽  
Traction Network ◽  
Electrified Railways

Abstract Electrified railways include a system of cable and overhead lines. An analysis of the operation of alternating current (AC) electrified railways sections shows that the value of the induced voltage caused by the operation of the traction network can significantly exceed the permissible level on adjacent disconnected high-voltage overhead lines. As a consequence, this leads to serious injuries to operating personnel, including deaths, failure of electrical equipment. From this point of view, 1x25 kV 50 Hz AC railway system networks are considered the most dangerous. The electromagnetic influence of the traction network of a double-track section of an AC railway on an adjacent 10 kV high-voltage overhead line for power supply of automatic block signalling is investigated in the offered paper. Emergency cases of traction network operation are considered: short-circuit situation and forced state. The calculations of short-circuit currents in the influencing inter-substation zone, as well as estimation of the induced voltage on the wires of the 10 kV disconnected high-voltage overhead line for various schemes of grounding, have been performed. The investigations were carried out on models built using the ATP-EMTP program.

Southern Hemisphere Seti Survey: Five Years of Project Meta II

1997 ◽  
Vol 161 ◽  
pp. 611-621
Author(s):  
Guillermo A. Lemarchand ◽  
Fernando R. Colomb ◽  
E. Eduardo Hurrell ◽  
Juan Carlos Olalde
Keyword(s):  
Southern Hemisphere ◽  
Scattering Theory ◽  
Galactic Plane ◽  
Narrow Band ◽  
Neutral Hydrogen ◽  
Sky Survey ◽  
Inertial Frames ◽  
Interstellar Scattering ◽  
Extraterrestrial Origin ◽  
Spectral Channels

AbstractProject META II, a full sky survey for artificial narrow-band signals, has been conducted from one of the two 30-m radiotelescopes of the Instituto Argentino de Radioastronomía (IAR). The search was performed near the 1420 Mhz line of neutral hydrogen, using a 8.4 million channels Fourier spectrometer of 0.05 Hz resolution and 400 kHz instantaneous bandwidth. The observing frequency was corrected both for motions with respect to three astronomical inertial frames, and for the effect of Earths rotation, which provides a characteristic changing signature for narrow-band signals of extraterrestrial origin. Among the 2 × 1013spectral channels analyzed, 29 extra-statistical narrow-band events were found, exceeding the average threshold of 1.7 × 10−23Wm−2. The strongest signals that survive culling for terrestrial interference lie in or near the galactic plane. A description of the project META II observing scheme and results is made as well as the possible interpretation of the results using the Cordes-Lazio-Sagan model based in interstellar scattering theory.

Dynamical Scattering in Electron Diffraction of wet Protein Crystals

1980 ◽  
Vol 38 ◽  
pp. 42-43
Author(s):  
B. B. Chang ◽  
D. F. Parsons
Keyword(s):  
Electron Diffraction ◽  
Scattering Theory ◽  
Protein Crystals ◽  
Electron Diffraction Data ◽  
Specimen Thickness ◽  
Major Question ◽  
X Ray ◽  
Scattering Effects ◽  
Diffraction Patterns ◽  
Acceleration Voltage

The significance of dynamical scattering effects remains the major question in the structural analysis by electron diffraction of protein crystals preserved in the hydrated state. In the few cases (single layers of purple membrane and 400-600 Å thick catalase crystals examined at 100 kV acceleration voltage) where electron-diffraction patterns were used quantitatively, dynamical scattering effects were considered unimportant on the basis of a comparison with x-ray intensities. The kinematical treatment is usually justified by the thinness of the crystal. A theoretical investigation by Ho et al. using Cowley-Moodie multislice formulation of dynamical scattering theory and cytochrome b5as the test object2 suggests that kinematical analysis of electron diffraction data with 100-keV electrons would not likely be valid for specimen thickness of 300 Å or more. We have chosen to work with electron diffraction patterns obtained from actual wet protein crystals (rat hemoglobin crystals of thickness range 1000 to 2500 Å) at 200 and 1000 kV and to analyze these for dynamical effects.

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