References of "Guerard, Suzanne"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailAeolian vibration on power-line conductors, evaluation of actual self damping
Guérard, Suzanne ULg; Godard, bertrand; Lilien, Jean-Louis ULg

in IEEE Transactions on Power Delivery (2011), 26(4), 2118-2122

Aeolian vibrations of power lines are induced by Von Karman vortex shedding. Without dampers, the amplitude of vibration very much depends on conductor self damping, which may be very low. The purpose of ... [more ▼]

Aeolian vibrations of power lines are induced by Von Karman vortex shedding. Without dampers, the amplitude of vibration very much depends on conductor self damping, which may be very low. The purpose of this paper is to show measurements of these vibrations carried out by a new experimental device which is able to perform continuous measurements in the full range of frequencies and amplitudes. In this paper, 550 hours of continuous recording on four different conductors placed in similar conditions is detailed. An evaluation of self damping power, based on observations is proposed. [less ▲]

Detailed reference viewed: 61 (19 ULg)
Full Text
Peer Reviewed
See detailPower Line conductors self damping : a new approach.
Guérard, Suzanne ULg; Lilien, Jean-Louis ULg

in Proceedings of the 9th International Symposium on Cable Dynamics (2011, October)

Up to now, self damping data generally comes from dynamic tests performed on test spans which length is of the order of some tens of meters. Those tests rely on the assumption that the conductor self ... [more ▼]

Up to now, self damping data generally comes from dynamic tests performed on test spans which length is of the order of some tens of meters. Those tests rely on the assumption that the conductor self damping changes the amplitude of incident and reflected travelling wave. In other words, there are no standing wave within a vibrating conductor and in practice, the amount of self damping is deduced from measurements of vibration amplitudes at adjacent “false vibration nodes”. The corresponding measurements require lots of dexterity and accuracy. This paper investigates the possibility of deducing the self damping properties of power line conductors from a series of tests performed quasi statically on a short prestressed conductor sample. Data recorded by Godinas [1] on 4 m long prestressed conductor samples has been used as an input (the conductors used are made of aluminium alloy, type AMS). This data was obtained by applying a cyclic quasi-static bending moment in the middle of the conductor sample and recording the corresponding strains. The experiment was reproduced at several prestress levels. A mining and analysis of this data has been performed so that in a first time the relationship between moment and curvature can be adequately defined. Then the corresponding internal work has been computed analytically (per integration). Finally a formulation for the self damping per unit length is proposed as a function of the antinode amplitude of vibration, frequency, conductor tension, bending stiffness, mass per unit length plus a special parameter called “b”. The latter parameter has the dimension of energy [J]. The corresponding results are found to be consistent with those deduced from the widely used “power law”, using Noiseux’s exponents [2, 3]. Also, a simplified version of the formula shows that the sensitivity of the self damping to the vibration amplitude, frequency and tension is comparable to that found by others authors using another self damping measurement technique [1], but with the difference that in this case, the exponents for frequency, amplitude and tension are integers, fully justified by the physics behind the phenomenon of damping. [less ▲]

Detailed reference viewed: 55 (4 ULg)
Full Text
Peer Reviewed
See detailOriginal real-time observations of aeolian vibrations on power-line conductors
Godard, Bertrand; Guérard, Suzanne ULg; Lilien, Jean-Louis ULg

in IEEE Transactions on Power Delivery (2011), 26(4), 2111-2117

Aeolian vibrations of power lines are induced by Von Karman vortex shedding. Vortex shedding is characterized by vibration frequencies in the approximate range of 3-100 Hz (sometimes higher) and by ... [more ▼]

Aeolian vibrations of power lines are induced by Von Karman vortex shedding. Vortex shedding is characterized by vibration frequencies in the approximate range of 3-100 Hz (sometimes higher) and by amplitudes that can reach conductor diameter for the lower range of frequencies, under very slow to medium wind speed (0.5 m/s to about 7 m/s). Conductor vibration causes localized bending, which may cause fatigue failure of the conductor strands. The amplitude of vibration very much depends on conductor self damping, which may be very low. The purpose of this paper to show measurements of these vibrations carried out by a new experimental device (developed by the authors), which is able to perform continuous measurements in the full range of frequencies and amplitudes. A statistical overview of measurements is presented and Lifetime is estimated. [less ▲]

Detailed reference viewed: 50 (18 ULg)
Full Text
Peer Reviewed
See detailVIBRATIONS OF A SHORT SPAN, COMPARISON BETWEEN MODELIZATION AND MEASUREMENTS PERFORMED ON A LABORATORY TEST SPAN
Guérard, Suzanne ULg; Lilien, Jean-Louis ULg; Van Dyke, Pierre

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

In the first part of the present paper, experiments carried out on IREQ laboratory cable test bench were described. One of the objectives of these experiments was to collect all the required data to ... [more ▼]

In the first part of the present paper, experiments carried out on IREQ laboratory cable test bench were described. One of the objectives of these experiments was to collect all the required data to validate the modelization of this cable test bench vibrating at its eigen frequencies. Conductor excitation was performed by a vibration shaker. In the present paper, the first modelization results are presented. The model used is a beam element model, with an average value of conductor bending stiffness. For certain of the simulations, some material damping was introduced through the use of a visco-elastic material. The vibration shaker is modelled by a harmonic force of adequate amplitude and location. The results obtained with this model put in evidence the impact of tension variations on such span length, which makes it difficult to obtain a resonance. Also, computed mode shapes are in good agreement with the reality, and time response of the model with a concentrated mass enabled us to reproduce some interesting observed phenomena. [less ▲]

Detailed reference viewed: 62 (6 ULg)
Full Text
Peer Reviewed
See detailEvaluation of power line cable fatigue parameters based on measurements on a laboratory cable test span
Guérard, Suzanne ULg; van dyke, Pierre; Lilien, Jean-Louis ULg

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 ▲]

Detailed reference viewed: 130 (8 ULg)
Full Text
Peer Reviewed
See detailAeolian vibrations on High Voltage Lines .Comparative self damping as evaluated on the field
Lilien, Jean-Louis ULg; Destiné, Jacques ULg; Gillis, Jean-Marie ULg et al

(2008, August)

New ways to measure continuously in real time, aeolian vibrations.

Detailed reference viewed: 129 (27 ULg)
Full Text
Peer Reviewed
See detailMicrosystem array for live high voltage lines monitoring
Lilien, Jean-Louis ULg; Guerard, Suzanne ULg; Godard, Bertrand ULg et al

(2006, August)

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

Detailed reference viewed: 72 (8 ULg)
Full Text
Peer Reviewed
See detailPower lines real time monitoring
Lilien, Jean-Louis ULg; Guerard, Suzanne ULg; Godard, Bertrand ULg et al

in Zamrik, Sam Y. (Ed.) Proceedings of the 11th ICPVT conference (2006, July)

How to access real time data of ampacity of power lines.

Detailed reference viewed: 68 (8 ULg)
Full Text
Peer Reviewed
See detailArray of microsystem for live monitoring of high voltage power lines
Renson, Luc ULg; Jamar, Claude ULg; Guérard, Suzanne ULg et al

in Proceedings of the 1st IOMAC (2005, April)

How to use microsystems placed on power lines environment.

Detailed reference viewed: 123 (14 ULg)
Full Text
See detailFinit element modelling of an asynchronous motor with one broken rotor bar, comparison with the data recorded on a prototype and material aspects
Guérard, Suzanne ULg; Gyselinck, Johan; Lecomte-Beckers, Jacqueline ULg

in Bulletin Scientifique de l'AIM (Association des Ingénieurs Electriciens sortis de l'Institut Electrotechnique Montefiore) (2005), 1

This work studies the problem of broken rotor bars in cage induction motors. To this aim, an induction machine from WEG Motors was modelled by means of the finite element method. The motor modelled is a ... [more ▼]

This work studies the problem of broken rotor bars in cage induction motors. To this aim, an induction machine from WEG Motors was modelled by means of the finite element method. The motor modelled is a 18.5 kW four-pole induction motor with a straight rotor cage. The field distribution and stator phase currents were computed for a motor without broken rotor bars and for a motor with one broken rotor bar. The computed stator phase currents were compared to the ones recorded on motors respectively no broken rotor bar and with one broken rotor bar. The FE model and an equivalent scheme of the motor permitted to show that the resistance of the rotor cage was higher than expected, considering only the temperature effect on the conductivity of the rotor bars. A metallurgic analysis of the aluminium alloy of two rotor bars revealed the presence of a very high density of silicon and silicon oxide inclusions, as well as the presence of shrinkages and cracks, which have a negative impact on both conductivity and mechanical strength. A corrected value of the rotor bar conductivity was used in the finite element model and led to a good agreement with the experimental results. The field perturbation associated with a broken rotor bar produces a concentration of flux near the bar ahead of the broken one, considering the counterclockwise direction of rotation of the rotor. This flux concentration results in higher current values and hence in higher stresses in the bar ahead of the broken one. [less ▲]

Detailed reference viewed: 86 (6 ULg)