Authors

Christophe Volat, Lionel Duvillaret, Frédéric Lecoche, Jean Dahdah, Gwenael Gaborit

Abstract

The possibility of perturbation-free electric-field mapping could give very helpful information concerning possible fault origins in electrotechnical installations during operation or during conception phases. For that purpose, we have developed ultra compact and fully dielectric pigtailed optical sensors for a simultaneous 2-components electric-field measurement. Made of high dielectric strength materials, these millimeter-size sensors can probe the transient temporal profiles of two electric field components inside an electric arc for instance. Their measurement dynamic covers the V/m up to MV/m electric-field strength range. The response of these optical sensors is flat from 30 Hz up to more than 10 MHz, giving a unique opportunity to make in situ diagnostics during a lightning shock wave inside electrotechnical installations. These sensors also exhibit a temperature-dependent free response and can be employed either in gazes or liquids like water or oil. Some electric-field mapping and in situ electric arc measurement will be presented during the conference.

Introduction

Diagnostics of faults in electrotechnical installations during operation or during conception phases remains a difficult challenge. Indeed, contactless characterization of the electrical signal can be required in order to avoid disturbance on the electrical device to be characterized. While antennas constitute a convenient technique to perform remote measurement of the radiated electric (E) field, their metallic constitution and the induced invasiveness limit the possibilities of high strength field measurement [1]. Electro-optic (EO) technique, based on the modification of a crystal indices by the electric field, is used from several decades to characterize guided or radiated electric field. The non-centrosymetric crystal has to be probed by a laser beam and an optical fibre cable is necessary to carry the optical wave and to develop remote and non-invasive EO sensors. Such pigtailed E-field transducers appear in the years 2000’s [2], [3], [4], [5], [6], [7]…

Reference

Electrical Insulation Conference (EIC), 2013 IEEE / 13642124 / 10.1109/EIC.2013.6554268 / 15 July 2013

I contact Kapteos for more information