Commissariat &#xc0; L'&#xc9;nergie Atomique Et Aux &#xc9;nergies Alternatives

Win Ms

Laurent Sommervogel

Josy Cohen

Marc Olivas

Luca Incarbone

Arnaud Peltier

A method uses at least: one line made up of at least two conductors insulated by a material whose insulation impedance depends locally on the temperature, the line running through the installation; a reflectometer periodically transmitting a reflectometry signal at one end of the line, the signal being propagated along the line, the reflectometer measuring the echoes received and comparing the amplitudes of the echoes with a given reference; a hot spot being detected when the amplitudes of a given number of successive echoes are greater than the given reference, the echoes being provoked by a local reduction of the value of the insulation impedance.

Method and device for detecting hot points in a facility, especially for detecting leaks in air ducts

A complete injection signal is provided having a digital spectrum formed from components weighted by a set of coefficients, in a preliminary step, the coefficients of the components included within a frequency band are attenuated resulting in an incomplete digital spectrum being obtained; in a next step, the analog signal composed from the incomplete digital spectrum is injected into the electrical line; in a next step, the echo corresponding to the injected signal is measured; in a next step, the digital spectrum of the echo is calculated; in a next step, the digital spectrum of the echo of the complete analog signal if the latter had been injected is estimated, the kcomponent of the estimated complete digital spectrum being equal to the kcomponent of the digital spectrum of the echo received multiplied by the ratio between the kcomponent of the digital spectrum of the complete injection signal over the kcomponent of the incomplete digital spectrum; in a next step, the measurement of the reflectogram of the line is obtained based on the estimated complete digital spectrum.

Reflectometry method and device for diagnosing cables in use

A method for automatically measuring physical characteristics of a cable, comprises at least the following steps: positioning on said cable of means for creating an artificial singularity; the injection, at a point of said cable, of an electrical test signal; acquisition of said signal reflected on the singularities that said cable includes so as to produce a first reflectogram; measurement, on said reflectogram, of the temporal position &#x394;t of the peak of the signal derived from its reflection on said artificial singularity; determination of the propagation velocity v=2x/&#x394;t of the signal in said cable from the temporal position &#x394;t and from the position x of said means for creating an artificial singularity on the cable.

Method and device for automatically measuring physical characteristics of a cable, in particular the propagation velocity

A method of testing a cable by distributed reflectometry, comprises: injecting into the cable a first periodic signal and a second periodic signal having the same number N of periods and the same number M of samples per period as the first signal; acquiring a measurement of the reflection, from impedance discontinuities of the cable, of each of said first and second signals; taking the average of said measurements of the reflection of at least one of said first or second signals over all of its periods to produce at least one reflectogram; determining the positions of faults in the cable on the basis of at least the reflectogram; the method being wherein each period of the second signal is injected into the cable with a delay or an advance which has an increasing predetermined absolute value for each successively injected period.

Growing community of inventors

Jouy en Josas, France

Laurent Sommervogel