Mixture of hydrofluoroolefine and hydrofluorocarbide to improve the internal ARC resistance in medium and high voltage electric apparatus

Patent metadata

Field	Value
Publication number	US-9293280-B2
Application number	US-201314370378-A
Country	US
Kind code	B2
Filing date	Mar 14, 2013
Priority date	Mar 16, 2012
Publication date	Mar 22, 2016
Grant date	Mar 22, 2016

Abstract

The invention relates to the use of a mixture of a hydrofluoroolefin and a hydrofluorocarbon, optionally combined with another fluorinated gas, as an electrical insulation medium and/or an electric arc extinguishing medium in a medium-voltage electrical apparatus. The invention also relates to a medium- or high-voltage electrical apparatus in which such a mixture provides electrical insulation and/or electric arc extinguishing.

First claim

The invention claimed is:

1. A method of extinguishing electrical arcs, comprising:
providing a gas medium to extinguish the electrical arcs,
wherein the gas medium comprises at least one hydrofluoroolefin with three carbon atoms and one hydrofluorocarbon.

2. The method according to claim 1 , wherein the hydrofluoroolefin is trans-1,3,3,3-tetrafluoro-1-propene, 2,3,3,3-tetrafluoro-1-propene or 1,2,2,5-pentafluoro-1-propene.

3. The method according to claim 1 , wherein the hydrofluorocarbon is 1,1,1,2,3,3,3-heptafluoropropane, pentafluoroethane or 1,1,1,2-tetrafluoroethane.

4. The method according to claim 1 , wherein the gas medium further comprises a fluoroketone.

5. The method according to claim 1 , wherein the gas medium further comprises a dilution gas, wherein said dilution gas is air, oxygen, carbon dioxide or a mixture thereof.

6. The method according to claim 1 , wherein partial pressure of the hydrofluorocarbon and of the hydrofluoroolefin in the gas medium is chosen as a function of a minimum temperature of an apparatus so as not to create a liquid phase according to Raoult's law at a minimum temperature of use of the apparatus.

7. The method according to claim 6 , wherein the apparatus is a high or medium voltage electrical substation.

8. The method according to claim 6 , wherein the minimum temperature (T min ) is −30° C., −25° C., −15° C. or 0° C.

9. The method according to claim 4 , wherein the fluoroketone is decafluoro-2-methylbutan-3-one.

10. A medium voltage electrical apparatus comprising:
a sealed chamber containing electrical components; and
a gas medium, wherein the gas medium comprises a hydrofluoroolefin with three carbon atoms and a hydrofluorocarbon.

11. The electrical apparatus according to claim 10 , wherein
the hydrofluoroolefin is trans-1,3,3,3-tetrafluoro-1-propene, 2,3,3,3-tetrafluoro-1-propene, or 1,2,2,5-pentafluoro-1-propene, and
the hydrofluorocarbon is 1,1,1,2,3,3,3-heptafluoropropane, pentafluoroethane, or 1,1,1,2-tetrafluoroethane.

12. The electrical apparatus according to claim 10 , wherein the gas medium further comprises a dilution gas.

13. The electrical apparatus according to claim 12 , wherein the dilution gas is air, oxygen, carbon dioxide, or a mixture thereof.

14. The electrical apparatus according to claim 10 , wherein the hydrofluoroolefin and the hydrofluorocarbon are present in the gas medium with proportions defined according to Raoult's law so as not to create a liquid phase at a minimum temperature of use of the apparatus.

15. The electrical apparatus according to claim 10 , wherein said electrical apparatus is an electrical transformer with gas insulation, a line with gas insulation for transporting or distributing electricity or a connecting/disconnecting electrical apparatus.

16. The method according to claim 2 , wherein the hydrofluorocarbon is 1,1,1,2,3,3,3-heptafluoropropane, pentafluoroethane or 1,1,1,2-tetrafluoroethane.

17. The method according to claim 16 , further comprising adding a dilution gas to the gas medium, wherein the dilution gas is air, oxygen, carbon dioxide or a mixture thereof, and
wherein partial pressure of the hydrofluorocarbon and of the hydrofluoroolefin in the gas medium is chosen as a function of a minimum temperature of an apparatus so as not to create liquid phase according to Raoult's law at a minimum temperature of use of the apparatus.

18. The electrical apparatus according to claim 13 , wherein said electrical apparatus is an electrical transformer with gas insulation, a line with gas insulation for transporting or distributing electricity or a connecting/disconnecting electrical apparatus.

19. The electrical apparatus according to claim 15 , wherein the hydrofluoroolefin and the hydrofluorocarbon are present in the gas medium with proportions defined according to Raoult's law so as not to create liquid phase at a minimum temperature of use of the apparatus.

Assignees

• Schneider Electric Ind Sas

Inventors

• Piccoz Daniel
• Maladen Romain
• Ferreira Da Costa Manuel

Classifications

• H01B3/56

  gases · CPC title

• H01H33/22 Primary

  Selection of fluids for arc-extinguishing · CPC title

• H01H2033/566

  Avoiding the use of SF6 · CPC title

• H01H33/562

  Means for avoiding liquefaction or for disposing of liquefaction products · CPC title

• H02B13/055

  Features relating to the gas · CPC title