Patents Assigned to GEC Alsthom T & D Balteau
  • Patent number: 6127817
    Abstract: An electro-optic voltage sensor comprises a voltage divider connected to an electric line and to ground and having two insulative compartments separated by an intermediate electrode connected to a Pockels cell. The intermediate electrode supplies to the Pockels cell a reduced voltage derived from the voltage supplied by the electric line to the voltage divider. Each insulative compartment comprises a homogeneous dielectric block with a thickness dependent on the division ratio of the voltage divider. The electro-optic voltage sensor has a very high safety level vis a vis the risk of strong short-circuits combined with mechanical and thermal stability guaranteeing great accuracy of operation and great reliability without special maintenance requirements.
    Type: Grant
    Filed: June 5, 1998
    Date of Patent: October 3, 2000
    Assignee: GEC Alsthom T&D Balteau
    Inventor: Denis Chartrefou
  • Patent number: 5890096
    Abstract: The unconventional measurement transformer for protection and/or measurement equipment of a three-phase electricity grid delivers digital information representative of a voltage or of a current of an electricity line by making use of optical sensors that are provided in sufficient number to achieve a certain amount of redundancy in the measurement paths. The output paths of the optical sensors are processed by digital processing means to validate said voltage or current digital information by a majority vote. Advantage is taken of features specific to three-phase high voltage and to the performance of such optical sensors to reduce the number of optical sensors required in an unconventional measurement transformer to obtain a degree of redundancy.
    Type: Grant
    Filed: November 5, 1996
    Date of Patent: March 30, 1999
    Assignee: GEC Alsthom T & D Balteau
    Inventors: Denis Chatrefou, Jean-Francois Mironneau, Philippe Delbos
  • Patent number: 5886265
    Abstract: An optical vibration sensor includes a built-in blade provided with a system for reflecting light, a system for directing light onto the reflecting system, system for collecting the light reflected by the reflecting system and a system for analyzing the intensity and/or the frequency and/or the phase of the reflected light. The blade forms an integral part of an appropriately cut block.
    Type: Grant
    Filed: February 21, 1997
    Date of Patent: March 23, 1999
    Assignee: GEC Alsthom T & D Balteau
    Inventor: Denis Chatrefou