Use of a mixture comprising a hydrofluoroolefin as a medium-voltage arc-extinguishing and/or insulating gas and medium-voltage electrical device comprising same

Patent metadata

Field	Value
Publication number	US-9491877-B2
Application number	US-201214130786-A
Country	US
Kind code	B2
Filing date	Jul 5, 2012
Priority date	Jul 5, 2011
Publication date	Nov 8, 2016
Grant date	Nov 8, 2016

Abstract

The invention relates to the use of a mixture comprising a hydrofluoroolefin, possibly associated with a dilution gas, as a gaseous electrical insulation and/or electrical arc extinguishing medium in substation medium-voltage electrical device.
It also relates to medium-voltage electrical device in which electrical insulation and/or electrical arc extinguishing is (are) performed by a gaseous medium comprising hydrofluoroolefin, possibly associated with a dilution gas.

First claim

The invention claimed is:

1. A process for electrically insulating and/or electrical arc extinguishing an electrical device having a sealed enclosure for containing electrical components in a gaseous medium under pressure, the process comprising:
selecting a minimum service temperature (T min ) of the electrical device;
selecting a hydrofluoroolefin with three carbon atoms and a dilution gas to be provided as a mixture in said enclosure such that said mixture having a global warming potential (GWP) lower than the global warming potential of the hydrofluoroolefin; and
providing said mixture in the sealed enclosure such that the hydrofluoroolefin is present in the mixture at a molar percentage (M HFO ) at least equal to 95% of the molar percentage M determined by the formula M=(P HFO /P mixture )×100, in which P mixture is a pressure of the mixture at 20° C. in the electrical device and P HFO is a pressure that at 20° C. is equivalent to the saturated vapour pressure (SVP) of the hydrofluoroolefin at said selected minimum service temperature (T min ) of the electrical device.

2. The process of claim 1 , wherein the hydrofluoroolefin is trans-1,3,3,3-tetrafluoro-1-propene (HFO-1234ze).

3. The process of claim 1 , wherein the hydrofluoroolefin is 2,3,3,3-tetrafluoro-1-propene (HFO-1234yf).

4. The process of claim 1 , wherein the dilution gas is selected from the group consisting of air, nitrogen, oxygen, carbon dioxide, and a mixture of these gases.

5. The process of claim 1 , wherein the hydrofluoroolefin molar percentage (M HFO ) is between 99% and 110% of the molar percentage M.

6. The process of claim 1 , wherein the selecting a minimum temperature (T min ) comprises selecting a temperature which ranges from −50° C. to 0° C.

7. The process of claim 1 , wherein the electrical device is a substation medium voltage electrical device.

8. The process of claim 1 , wherein the minimum service temperature (T min ) is selected from the group consisting of −50° C., −45° C., −40° C., −30° C., −25° C., −15° C., −10° C., −5° C., and 0° C.

9. A medium-voltage electrical device having a minimum service temperature (T min ), comprising:
a sealed enclosure in which electrical components are located together with a gaseous medium, under pressure, for providing electrical insulation and/or electric arc extinguishing within this enclosure,
wherein the gaseous medium is a mixture of a hydrofluoroolefin with three carbon atoms and a dilution gas such that the mixture has a global warming potential (GWP) lower than the global warming potential of the hydrofluoroolefin, and
a molar percentage (M HFO ) of the hydrofluoroolefin in the mixture is at least equal to 95% of a molar percentage M determined by the formula: M=(P HFO /P mixture )×100, in which P mixture is a pressure of the mixture at 20° C. in the electrical device and P HFO is a pressure that at 20° C. is equivalent to the saturated vapour pressure (SVP) of the hydrofluoroolefin at the minimum service temperature (T min ) of the electrical device.

10. The device according to claim 9 , wherein the hydrofluoroolefin is trans-1,3,3,3-tetrafluoro-1-propene (HFO-1234ze) or 2,3,3,3-tetrafluoro-1-propene (HFO-1234yf).

11. The device according to claim 9 , wherein the dilution gas is selected from the group consisting of air, nitrogen, oxygen, carbon dioxide, and a mixture of these gases.

12. The device according to claim 9 , wherein the hydrofluoroolefin molar percentage (M HFO ) is between 99% and 110% of the molar percentage M.

13. The device of claim 9 , which is a gas-insulated electrical transformer, a gas-insulated line for transporting or distributing electricity or an electrical connection/disconnection device.

Assignees

• Kieffel Yannick
• Girodet Alain
• Piccoz Daniel
• Maladen Romain
• Schneider Electric Ind Sas

Inventors

• Kieffel Yannick
• Girodet Alain
• Piccoz Daniel
• Maladen Romain

Classifications

• H05K5/06 Primary

  Hermetically-sealed casings {(specially adapted for small components H05K5/0095)} · CPC title

• H01H33/56

  Gas reservoirs · CPC title

• H01H2033/566

  Avoiding the use of SF6 · CPC title

• H01B3/56 Primary

  gases · CPC title

• B65B31/00

  Packaging articles or materials under special atmospheric or gaseous conditions; Adding propellants to aerosol containers · CPC title