EPRI Transmission Line Reference Book : wind-induced Conductor Motion.

Book published by EPRI - second edition (2009)

This book summarize worldwide knowledge on power line conductor wind-induced movements, including :- aeolian vibrations; - Fatigue of Overhead conductors; - Galloping; - bundle conductor oscillations ... [more ▼]

This book summarize worldwide knowledge on power line conductor wind-induced movements, including :- aeolian vibrations; - Fatigue of Overhead conductors; - Galloping; - bundle conductor oscillations; - overhead fiber optic cables; - other motions. [less ▲]

Evaluation of power line cable fatigue parameters based on measurements on a laboratory cable test span

in Lilien, Jean-Louis (Ed.) EIght International symposium on Cable Dynamics, ISCD 2009 (2009)

The present paper describes experiments carried out on IREQ laboratory cable test bench. Test span arrangement is a 63.15m cable span with termination ends designed so as to minimize energy dissipation. A ... [more ▼]

The present paper describes experiments carried out on IREQ laboratory cable test bench. Test span arrangement is a 63.15m cable span with termination ends designed so as to minimize energy dissipation. A shaker provides a vertical alternating force to the conductor. During the experiments, a maximum of information on mode shape is collected: location of nodes, antinode amplitude of vibration, relative displacement at 44.5, 89, and 178mm from the last point of contact with the metallic clamp. Several configurations are studied: span equipped with an homogeneous steel cable, span equipped with an ACSR Crow conductor, sometimes in combination with other equipments such as a vibration damper or a local mass, to investigate how the presence of such devices impacts conductor vibrations. It results from these experiments an interesting comparison of two widely used fatigue indicators, the relative displacement Yb 2 (also called “bending amplitude”) and fymax (the product of antinode amplitude of vibration by frequency). Also, collected data gives indirect information on conductor variable bending stiffness. [less ▲]

Modélisation numérique des courants et tensions de contact dans des habitations

in Actes de 6ème conférence européenne sur les méthodes numériques en électromagnétisme (NUMELEC 2008) (2008, December)

Un modèle d’installation électrique d’habitation avec une ligne à haute tension est développé avec la méthode "Partial Element Equivalent" (PEEC). Cette étude a pour but de déterminer l’existence des ... [more ▼]

Un modèle d’installation électrique d’habitation avec une ligne à haute tension est développé avec la méthode "Partial Element Equivalent" (PEEC). Cette étude a pour but de déterminer l’existence des courants et tensions induits dans une maison et d’évaluer leur amplitude. Ensuite, nous caractérisons l’influence d’un réseau d’habitations et du type de prise de terre sur ceux-ci. Cette partie du travail nous permet d’obtenir un ensemble de facteurs influençant le niveau des courants induits. Ce papier montre qu’il est possible de déterminer des configurations pour minimiser ces courants dans un réseau d’habitations. [less ▲]

Effects of extremely low frequency electromagnétic fields (ELF) on human beings. An electrical engineer viewpoint.

in Revue d'électricité et d'électronique industrielle - tijdschrift voor elektriciteit en industriele elektronika (2008), 3

Since the early seventies, potential health risks from Extremely Low Frequency (ELF) exposure (50 Hz) have been extensively treated in the literature (more than 1000 references registered by WHO1, 2007 ... [more ▼]

Since the early seventies, potential health risks from Extremely Low Frequency (ELF) exposure (50 Hz) have been extensively treated in the literature (more than 1000 references registered by WHO1, 2007). After 30 years of worldwide research, the major epidemiological output is the possible moderate increased risk (by a factor 2) of childhood leukaemia in case of a long exposure to an ambient magnetic flux density (B-field) higher than 0.4 μT. However, this fact has not been confirmed by in vivo and/or in vitro studies. Moreover it has not been validated by any adverse health biological mechanisms neither for adults nor for children. Nobody knows precisely what happens inside the body and what could be a hazardous health effect of the ELF fields at 50 Hz. International recommendations (ICNIRP2) are currently, for general public, not to exceed a B-field of 100 μT (50 Hz) and an E-field of 5 kV/m (50 Hz). The authors are looking for a signal generated in the biological process under electric interactions. Herein, a rough overview of typical values of ELF fields will be presented followed by a brief literature survey on childhood leukaemia and ELF. The potential carcinogenic effect of ELF would be linked to electrical disturbances in cell behaviour. The major concern linking childhood leukaemia and ELF is thus to determine the response of bone marrow cells under ELF fields.With that purpose, transmembrane potential will be targeted and linked to the E-field at that level. This paper is three-folded: First, the electric interactions between ambient ELF fields and the body are studied both qualitatively and quantitatively. Though no adverse health field threshold is defined, a minimum field level is fixed in order to discriminate inherent random noise, in agreement with NIEHS3. This is based on the fact that mechanisms become only plausible under field exposure above a certain strength. Different sources of internal E-field are analysed and classified according to their potential risk. Second, the hypothesis of contact current is detailed. Finally, key actions to undertake are highlighted. Based on the current state of the art and some authors’ own developments, this paper proposes simple low cost modifications of private electrical installations in order to annihilate the major source of potential effects of ELF. Particular emphasis is paid to the situation in Belgium as the authors are part of the BBEMG (see end note) and perform numerous measurements in Belgian residential homes. [less ▲]

New trends on real time measurement on power lines : application to ampacity, aeolian vibrations and others

Conference given outside the academic context (2008)

new trends in real time monitoring onpower lines using mycrosystems

A kinematic model for hysteretic dissipation of vibration energy for torsional damper and detuner.

in Lilien, Jean-Louis (Ed.) Proceedings of the 7th International Conference on Cable Dynamics (2007, December)

A description of the damping properties and model of a low frequency damper for power lines galloping.

State of the art of conductor galloping

Book published by CIGRE - document prepared by CIGRE Task Force B2.11.06 (2007)

Galloping is a low frequency, high amplitude wind induced vibration of both single and bundle conductors, with a single or a few loops of standing waves per span. Galloping has a major impact on the ... [more ▼]

Galloping is a low frequency, high amplitude wind induced vibration of both single and bundle conductors, with a single or a few loops of standing waves per span. Galloping has a major impact on the design of overhead lines, for both clearances and tower loadings. This book is giving an actualized state of the art of the phenomenon, the mechanisms and ways to control it. Based on observations in worldwide countries, new trends for galloping amplitudes and fatigue mechanisms associated are detailed. [less ▲]

Device, system and method for real-time monitoring of overhead power lines

in International Application published under the patent cooperation treaty (PCT) (2007)

Microsystem array for live high voltage lines monitoring

(2006, August)

The use of microsystems at very high electromagnetic fields on power lines to monitor movements.

Electrification Rurale. Vers une technique innovatrice pour l'Afrique.

in Revue d'electricité et d'électronique industrielle (2006), N°1-2006

In many developing countries , there are a lot of high voltage lines which cross many regions to supply electricity to the main towns or connect to networks the distanced electric substations . These ... [more ▼]

In many developing countries , there are a lot of high voltage lines which cross many regions to supply electricity to the main towns or connect to networks the distanced electric substations . These lines, used for supplying electricity to big towns, cross a lot of villages whose people broadly poor hope to be supplied with electricity without a suitable solution. However it seems very deplorable that the power conducted by these lines doesn’t profit to surrounding population. Unfortunately , for these villages , the use of classical substations is too expensive to the power distributors because of high cost of investment and production for these potential scattered consumers with the low demand of electricity. This paper presents the original solution settled in 2002 in one of the village located in Congo Brazzaville and continue to operate correctly in 2006. It is a new power transformer, based on the technique of SF6 measuring transformer, which is connected on one phase of the high voltage line 220kV and which produces the low voltage 230 V directly useful by the rural population. This prototype sample for the rural electrification has been designed to deliver a power of 50kVA. A cheap and robust system ! It requires a large popularization, mainly in sub saharian Africa that has got many such opportunities. Outside the role of bulk power transmission, the high voltage line is now also able to distribute a part of it. [less ▲]