Device and method for monitoring rooms equipped with high-voltage apparatuses

Patent metadata

Field	Value
Publication number	US-9513204-B2
Application number	US-201514638712-A
Country	US
Kind code	B2
Filing date	Mar 4, 2015
Priority date	Sep 4, 2012
Publication date	Dec 6, 2016
Grant date	Dec 6, 2016

Abstract

A monitoring device for determining the concentration of a dielectric insulation fluid such as a perfluoroketones in a room housing at least one high-voltage electrical apparatus and being accessible by humans essentially without modifying the room conditions, for example the room being a part of an air-insulated substation, with the monitoring system including one or more sensors for determining an emission and/or absorption of the dielectric insulation fluid molecules at at least one wavelength or wavelength band of the electromagnetic wave spectrum.

First claim

The invention claimed is:

1. A system for monitoring a concentration of molecules present in a dielectric insulation medium in a room housing at least one medium voltage or high voltage electrical apparatus and being accessible by humans, comprising:
a monitoring device including at least one radiation sensor and a radiation source;
the monitoring device determining, via the at least one radiation sensor, in a non-local manner an averaged concentration-dependent electromagnetic property of the molecules present in the dielectric insulation medium at at least one wavelength or wavelength band of the electromagnetic wave spectrum, the dielectric insulation medium being an organic fluorine compound;
wherein the monitoring device determines the concentration of the molecules of the organic fluorine compound and monitors, in-situ, a dielectric strength of the dielectric insulation medium inside the room;
a controller, that is part of or connected to the monitoring device, controlling the dielectric strength of the dielectric insulation medium inside the room, the controller designed to detect, from the monitoring device, a fault concentration outside an allowed concentration range of the molecules in the room and to automatically initiate mitigating measures in response to changes in the concentrations of the dielectric insulation medium, the mitigating measures including injection of the dielectric insulation medium into the room, and
a supply system, including a reservoir and a nozzle, connected to the controller for a controlled injection of the dielectric insulation medium into the room.

2. The system of claim 1 , wherein the monitoring device is adapted to determine as the concentration-dependent electromagnetic property an emission and/or an absorption and/or a transmission and/or a scattering by the molecules.

3. The system of claim 1 , wherein the monitoring device determines
the concentration of the molecules, that are part of a dielectric insulation component C1 other than air or that provide to the dielectric insulation medium a dielectric strength greater than the dielectric strength of air, or
the concentration of such molecules, that are not part of a background gas present in the dielectric insulation medium, and that are not any one of the group consisting of: nitrogen, oxygen carbon dioxide, or
the concentration of such molecules that originate from chemical transformation of the dielectric insulation medium under arcing or ageing or chemical reactions in the room, or
the concentration of a partly fluorinated or fully fluorinated compound of an olefine, an alkane, a ketone or polyketone, an ether or polyether, and any mixtures thereof, or
the concentration of a partly fluorinated or fully fluorinated fluoroketone comprising exactly 5 or exactly 6 or exactly 7 or exactly 8 carbon atoms and any mixtures thereof.

4. The system of claim 1 , the monitoring device having a spectral sensitivity higher by a factor of at least 2 for the molecules to be monitored, the molecules to be monitored being molecules of a perfluoroketone, than for molecules of a background gas present in the dielectric insulation medium.

5. The system of claim 4 , the monitoring device having the spectral sensitivity higher by a factor of at least 10 for the molecules to be monitored, the molecules to be monitored being molecules of the perfluoroketone, than for the molecules of the background gas present in the dielectric insulation medium.

6. The system of claim 1 ,
wherein the at least one wavelength or wavelength band is in a spectral range of 200 nm to 20000 nm, or
wherein the at least one wavelength or wavelength band is in at least one of the spectral ranges: 200 nm to 400 nm, 1850 nm to 1950 nm, and 5000 nm to 20000 nm.

7. The system of claim 1 ,
wherein the sensor has sensing means for measuring an averaged emission and/or an averaged absorption and/or an averaged transmission by the molecules along a length in the room, the length being larger than a size of a door for accessing the room by a human or larger than a quarter length or even a half length of the room, and/or
wherein the sensor has sensing means that are arranged at two or more locations inside the room such that a transmission distance for electromagnetic radiation to be monitored is provided between the locations for sensing an averaged concentration of the molecules along the transmission distance between the locations, wherein the transmission distance extends along a length in the room, the length being larger than a size of a door of the room or larger than a quarter length or even half length of the room.

8. The system of claim 1 , wherein the sensor has sensing means that are arranged in the room at opposing or adjacent walls or at a ceiling or a floor of the room, such that a collimated beam of electromagnetic radiation is transmitted across a free-space part or a full length of the room, or
wherein the monitoring device comprises optical elements, including the radiation source, the at least one radiation sensor, a beamsplitter, and a mirror, that are arranged at different locations such that a collimated beam of electromagnetic radiation is transmitted across a free-space part or a full length of the room.

9. The system of claim 1 , wherein the sensor has sensing means, that are permanently installed in the room and/or that are arranged in an eye-safe region of the room and/or that are arranged in a region of the room that is not accessible by up-right walking humans.

10. The system of claim 1 , wherein the sensor has sensing means, that are arranged in regions of above-average field strengths in the room and/or that are arranged along non-encapsulated components of the electrical apparatus.

11. The system of claim 1 ,
wherein the at least one radiation sensor includes several sensors being arranged along a length in the room for monitoring an average of the concentration of the molecules, the length being larger than a size of a door for accessing the room by a human or larger than a quarter length or even a half length of the room, or
wherein the at least one radiation sensor includes an optical fiber arranged within the room to be monitored, wherein the optical fiber includes at least one active section at which a beam in the optical fiber interacts with the surrounding dielectric insulation medium, the dielectric insulation medium being a gas.

12. The system of claim 1 , the controller designed to detect a fault concentration below a minimal threshold concentration of the molecules for a given operational state of the electrical apparatus, and to automatically initiate mitigating measures in response to a deviation of the detected fault concentration from the minimal threshold concentration of the molecules.

13. The system of claim 1 ,
wherein a or the controller is connected to a temperature sensor monitoring the temperature of the room at more than one location, and/or
wherein the controller is connected to a supply system for a controlled injection of the molecules into the room.

14. The system of claim 1 ,
wherein the monitoring device is adapted to the room to monitor an average, being a spatially continuous average and/or a sampling-point average, of the concentration of the molecules, which are present in the dielectric insulation medium in the room, along an averaging path length in the room,
wherein the averaging path length is of the order of a dimension of the room, or of a dimension of a door for accessing the room by a human, or of a dimension of the at least one medium-voltage or high-voltage electrical apparatus.

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Assignees

• Paul Thomas Alfred
• Kramer Axel
• Ingold Mathias
• Abb Technology Ag

Inventors

• Paul Thomas Alfred
• Kramer Axel
• Ingold Mathias

Classifications

• H02B13/055

  Features relating to the gas · CPC title

• G01N15/06 Primary

  Investigating concentration of particle suspensions (by weighing G01N5/00; investigating sedimentation of particle suspensions G01N15/04; investigating individual particles G01N15/10) · CPC title

• H01H33/563

  comprising means for monitoring the density of the insulating gas · CPC title

• G01N21/31

  Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry {(G01N21/72 takes precedence)} · CPC title

• G01N21/3504 Primary

  for analysing gases, e.g. multi-gas analysis · CPC title