Publications de Pierre Zweiacker

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In this paper we present and discuss measurements of electric (vertical and radial) and magnetic fields from leaders and return strokes associated with lightning strikes to the 100 m tall Gaisberg tower in Austria obtained in 2007 and 2008. The fields were ...

The rising part of the current waveform observed when discharging an electrostatically charged person or test generator shows some phenomena which have not been explained satisfactorily. This paper describes an attempt to understand these effects using both experimental and numerical simulation. A special rotating system to simulate a defined, variable closing speed of contact has been built. The length of the arc is also measured and it can be shown that a strong correlation between arc-length and rising s

Reports detailed measurements of flux flow velocity-performed by direct observation with the magneto-optical technique-and electrical resistance in high purity polycrystalline rectangular lead and indium plates subjected to a transverse magnetic field Ha. The measurements illustrated flux flow resistance in the intermediate state and tested the basic flux flow concept governed by the following relations between the average electric field in the superconductor E, the velocity of the magneti

Experimental data characterizing indoor electric and magnetic fields radiated by power line communication (PLC) systems and used for the calculation of a local transfer function (coupling factor) are presented. It is shown that the indirect determination of electric field using magnetic field measurements and assuming a plane wave approximation may result in an underestimation of the electric field. Additionally, it is shown that the radiated field magnitudes vary significantly as a function of the position

The paper presents the characteristics of a system suitably developed to measure lightning current waveforms on the Santis Tower in Switzerland. The paper first describes the configuration of the system then presents the characteristics of the measurement ...

We propose to investigate the effect of electromagnetic fields on the moss Physcomitrella patens, and on the nematode Caenorhabditis elegans in the range of 900 MHz - 1 GHz. Physcomitrella patens is a plant whose developmental biology and genetics is well known and the nematode Caenorhabditis elegans has been completely sequenced and this organism has been and is still the most well known chordate as far as genetics, developmental and behavioural biology are concerned.

This paper examines the responses of four different types of shielded conduits to a direct lightning strike. The conduits are buried in the ground and run between two shielded enclosures, one of which is struck by lightning. An induced current flows on the conduit and this induces a voltage on the inner wires within the shield. Using a simple resistive model, this voltage is estimated and the effectiveness of the shielding provided by the various conduits is determined. A key element in the calculations is

Recent advances in the application of nontraditional methods and procedures for offline diagnosis and online monitoring of new and service-aged power transformers are discussed. Advanced offline methods are based on the main operational stresses (electrical, mechanical, thermal) and on typical failure modes: measurement of polarisation and depolarisation currents, electrical detection of partial discharges and measurement of the transfer function. A pilot installation of an online monitoring system on a str

A transmission-line type of EMP simulator, consisting of two conductors with a central parallel plate region has been designed, fabricated and tested. It has been named SEMIRAMIS-I, which stands for Simulateur Electromagnetique a Impulsion Raide pour des Mesures Industrielles et Scientifiques. This simulator can be energized by either a CW or a transient pulse source. Testing was performed with ELGAL's EM-103 pulser (20 kV-100 kV, 7-9 ns risetime, 150 ns FWHM). The desired working volume is about 3 m long×1

A bounded wave transmission line ENP simulator which achieves a very good confinement of the field inside its volume is described. Results of field mapping in free space and inside a shielded room are presented. These measurements have shown that the field decays very rapidly outside the structure, making it possible to use the antenna without disturbing its environment. It was also shown that when the simulator is used inside a Faraday cage, the reflections from the walls of the room do not produce signifi

In order to achieve control of HV cables after repair or preventive maintenance measurements should be performed on the installed cables. The authors present numerical studies on the wave reflection in the cable using the EM transients program. They show the present promises and limits of the method of partial discharge reflectometry

Experiments were carried out on high purity Pb to investigate the flux flow velocity and resistivity. A magnetooptical technique was used

Pierre Zweiacker

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Lightning Electromagnetic Fields at Very Close Distances Associated with Lightning Strikes to the Gaisberg Tower

The correlation of rising slope and speed of approach in ESD tests

Flux flow velocity and resistivity measurements in the intermediate state

Indoor radiated emission associated with power line communication systems

A system for the measurements of lightning currents at the Säntis Tower

INFLUENCE OF HF ELECTROMAGNETIC FIELDS ON THE DEVELOPMENT AND THE MOLECULAR BIOLOGY OF THE MOSS PHYSCOMITRELLA PATENS AND THE NEMATODE CAENORHABDITIS ELEGANS

Estimates of lightning-induced voltage stresses within buried shielded conduits

Development and application of new condition assessment methods for power transformers

SEMIRAMIS: an asymmetrical bounded wave EMP simulator with a good confinement inside the transmission line

A medium size NEMP radiation system used in a shielded room

Distortion of electric and magnetic fields from lightning due to close-by metallic structures

Measurement of Lightning Currents Using a Combination of Rogowski Coils and B-Dot Sensors

In situ control of HV cables during commissioning test operation or preventive maintenance using partial discharge reflectometry

Measurement of lightning currents using a combination of Rogowski coils and B-Dot sensors

Effect of Nearby Buildings on Electric and Magnetic Fields from Lightning

Effect of Nearby Buildings on Electromagnetic Fields from Lightning

Flux flow velocity and resistivity measurements in the intermediate state

First Direct Lightning Current Measurements on the Newly Instrumented Säntis Tower in Switzerland

Current Waveforms Associated with Positive Flashes Recorded on the Säntis Tower in Summer 2010

Instrumentation of the Säntis Tower for Lightning Current Measurement