Acoustic noise generated by air power reactor in open-air substation

in european transaction on electrical power (2006), 16(3, May-JUN), 297-310

Air core reactor generates disturbing noise in its environment. This paper is evaluating the noise generated by air-core reactor both by analytical and numerical methods. Detailed analysis is done on a ... [more ▼]

Air core reactor generates disturbing noise in its environment. This paper is evaluating the noise generated by air-core reactor both by analytical and numerical methods. Detailed analysis is done on a test case to evaluate why some discrepancies may occur between actual results and simulated ones. Trends to limit noise are also evaluated. [less ▲]

Overhead power lines real time monitoring : a future trend ?

Conference given outside the academic context (2005)

general overview of ampacity problem in power lines

Array of microsystem for live monitoring of high voltage power lines

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

How to use microsystems placed on power lines environment.

Short-circuit mechanical effects on outdoor HV substations with wide bundling.

in Conférence Internationale des grands réseaux électriques à haute tension - CIGRE (2004, August)

This paper presents results of a research project investigating the mechanical effects of short-circuit currents in high-voltage substations with conductor bundles. The experimental part was performed on ... [more ▼]

This paper presents results of a research project investigating the mechanical effects of short-circuit currents in high-voltage substations with conductor bundles. The experimental part was performed on two set-ups, called "100 kV arrangement" and "400 kV arrangement". Those two set-ups differed in the height of the crossarm, the phase-to-phase distance and the conductor sag. Additional parameters which were varied in the course of the experiments included the level and duration of the short-circuit current, the type and number of the spacers used and the bundle spacing. Various forces in the flexible busbar and the supporting structure were recorded during the tests and the stiffness as well as the eigenfrequency of the portals used for supporting the conductors were determined. The test results were evaluated with respect to the maxima of the pinch force, the tensile force and the drop force. They are presented and compared with existing assumptions and calculation methods. The results of this project shall enable IEC standardization committees and CIGRE working groups to carry on with their intended studies and establish a comprehensive method of calculating the mechanical effects in substations with bundle conductors. [less ▲]

Limiting windstorm effects on tower by the « low drag » cable

(2004, August)

Hurricane winds affect the flow around electrical conductor in a way that it may reach the critical (Drag crisis) and postcritical states. It is thus important to introduce the cable aerodynamic drag as ... [more ▼]

Hurricane winds affect the flow around electrical conductor in a way that it may reach the critical (Drag crisis) and postcritical states. It is thus important to introduce the cable aerodynamic drag as Reynolds-dependent when calculating the response of the power transmission line under hurricane. To represent the respective wind loading on cable, the turbulent, spatially non-uniform wind model is used. In order to assess the behaviour and cyclic fatigue loads under hurricane conditions of different transmission line conductors, the time response analyses were done. Results of comparative study of the smooth cable AERO-Z and classical multistrand cable, including the percentage of load reduction offered to supporting structure, are presented. [less ▲]

Wake-Induced Vibration in Power Transmission Line. Parametric study

in Flow Induced Vibration - FIV 2004 (2004, July)

The paper discusses some aspects of modeling the wake-induced vibrations of the bundle conductors in transmission lines. The wake coupling between subconductors is modeled with the modified Simpson’s ... [more ▼]

The paper discusses some aspects of modeling the wake-induced vibrations of the bundle conductors in transmission lines. The wake coupling between subconductors is modeled with the modified Simpson’s approach. In order to apply this model to the analysis of power transmission line (PTL), a modal representation of a span could be used. In present paper we study how application of Dynamic Reduction (Component Mode) technique may improve such analysis under finite-element approach. The present paper, to extent of authors’ knowledge, is the first where Component Mode method application is discussed to study the subspan oscillation. Finally, bundled conductors’ susceptibility to wake-induced vibrations is illustrated on an exemplary twin-bundle, three-subspan model. Effects of bundle parameters (initial subconductor spacing, frequency ratio, subconductor mass), and the means to account them when applying the component mode method are discussed. [less ▲]

Hurricane Simulation on Power Transmission Line

in Proceedings of the 5th International Conference on Cable Dynamics (2003, September)

The hurricane winds are characterized by high speeds, at which the « drag crisis » regime of flow around cable is achievable. That is why, in the calculation of the wind-induced movement of the overhead ... [more ▼]

The hurricane winds are characterized by high speeds, at which the « drag crisis » regime of flow around cable is achievable. That is why, in the calculation of the wind-induced movement of the overhead transmission line during hurricane, it is important to represent the cable aerodynamic drag as Reynolds-dependent. In order to assess the behaviour and fatigue resistance of the transmission line conductor under hurricane conditions, the Reynolds-dependent drag coefficient was introduced in the SAMCEF Mecano finite-element software. To represent the hurricane wind loading, the turbulent, spatially non-uniform wind model was used. Results of comparative study of the smooth cable AERO-Z and the classical multistrand cable, including the percentage of load reduction offered to supporting structure, are presented. [less ▲]

The mechanical effects of short-circuit currents in open air substations (Part II)

Book published by CIGRE (2002)

This book is a companion book of teh CIGRE brochure N° 105 (1996) on the same subject. It evaluates short-circuit mechanical effects and corresponding design loads in substation. It includes both rigid ... [more ▼]

This book is a companion book of teh CIGRE brochure N° 105 (1996) on the same subject. It evaluates short-circuit mechanical effects and corresponding design loads in substation. It includes both rigid and flexible bus-bars, Ac and DC network. It is divided in two volumes, the second one is giving numerous data and tests results of short-circuit. The first volume is detailing methods (simplified, medium and advanced ) to solve these problems. [less ▲]

Wind turbines turbulence effects on cable structures in their vicinity

in Proceedings of the ISCD 2001 (2001, May)

Actual wind turbines size can be as large as 80 meters diameter (1 MW and over). Behind the wind turbines, mean wind speed is sensibly reduced (approximately 50%) and turbulence severely increased. The ... [more ▼]

Actual wind turbines size can be as large as 80 meters diameter (1 MW and over). Behind the wind turbines, mean wind speed is sensibly reduced (approximately 50%) and turbulence severely increased. The spectral density power of disturbed wind can be assumed similar to classical wind but centred on the rotational speed of the motor. Due to classical speed and shape of wind turbine, corresponding key frequency for disturbed wind is close to one Hz. Any structure in the vicinity of wind turbine can be disturbed by the new wind spectrum created by the turbine, thus existing most of the time for wind speed up to 25 m/s. Cable structure, f.e. overhead lines, have clearly 1 Hz in their first modal shapes. This make them very sensible to buffeting due to the disturbed wind induced by the turbine. Due to continuous excitation, most of the year, fatigue may occur near clamping point and extra damping may be required as well as minimum distance from the wind turbine may be recommended. The anchoring tower (whose first eigenfrequency is generally close to 1 Hz for high voltage lines) will also be affected. This paper will present some simulations of overhead lines disturbances induced by wind turbine in their vicinity. The power spectral density of wind behind the turbine will be deduced from classical spectra of Davenport, but with adaptation due to the rotation of the turbine. Effects on cable will be shown and tentative recommendations of damping as well as clearances from the turbine will be suggested. [less ▲]

Calculation of spacer compression for bundle lines under short-circuit.

in IEEE Transactions on Power Delivery (2000), 15(N°2), 839-845

Short-circuit tests results and proposal of a new method to improve Manuzio formula on bundle conductors spacer compression.