Gas-insulated electrical apparatus comprising carbon dioxide, heptafluoroisobutyronitrile and a high content of oxygen

Patent metadata

Field	Value
Publication number	US-12176162-B2
Application number	US-202118001445-A
Country	US
Kind code	B2
Filing date	Jun 10, 2021
Priority date	Jun 11, 2020
Publication date	Dec 24, 2024
Grant date	Dec 24, 2024

Abstract

The present application concerns a medium- or high-voltage equipment including a leaktight enclosure in which there are located electrical components and a gas mixture for providing electrical insulation and/or for extinguishing electric arcs that are likely to occur in the enclosure, the gas mixture including heptafluoroisobutyronitrile, carbon dioxide, and a high content of oxygen.

First claim

We claim:

1. A medium- or high-voltage equipment including a leaktight enclosure in which there are located electrical components and a gas mixture for providing electrical insulation and/or for extinguishing electric arcs that are likely to occur in said enclosure, the gas mixture comprising heptafluoroisobutyronitrile, carbon dioxide and oxygen, wherein oxygen presents a molar percentage equal to or higher than 26%, in said gas mixture.

2. The equipment according to claim 1 , wherein oxygen in said gas mixture presents a molar percentage lying in a range of 28% to 50%.

3. The equipment according to claim 2 , wherein said gas mixture comprises:
from 40 mol % to 70 mol % of carbon dioxide,
from 2 mol % to 10 mol % of heptafluoroisobutyronitrile, and
from 28 mol % to 50 mol % of oxygen.

4. The equipment according to claim 1 , wherein oxygen in said gas mixture presents a molar percentage lying in range of 30% to 50%.

5. The equipment according to claim 4 , wherein said gas mixture comprises:
from 40 mol % to 68 mol % of carbon dioxide,
from 2 mol % to 10 mol % of heptafluoroisobutyronitrile, and
from 30 mol % to 50 mol % of oxygen.

6. The equipment according to claim 1 , wherein said gas mixture comprises:
from 40 mol % to 72 mol % of carbon dioxide,
from 2 mol % to 10 mol % of heptafluoroisobutyronitrile, and
at least 26 mol % of oxygen.

7. The equipment according to claim 1 , wherein part of the electrical components arranged inside the enclosure of said equipment is covered by solid insulating layers.

8. The equipment according to claim 1 , wherein said equipment is a gas-insulated electrical transformer, an overhead or buried gas-insulated line, a set of busbars for transporting or distributing electricity, an element for connection to other equipment in a network, or a connector/disconnector.

9. The equipment according to claim 1 , wherein said equipment presents a minimum pressure of 7.5 bars (i.e. 7500 hPa) absolute and a nominal pressure of 8.5 bars (i.e. 8500 hPa) absolute.

10. An use of a gas mixture comprising heptafluoroisobutyronitrile, carbon dioxide and oxygen, as a gas for electrical insulation and/or for electric arc extinction in medium- or high-voltage equipment, in which part of the equipment may further be covered with a solid insulating layer, wherein oxygen presents a molar percentage equal to or higher than 26%, in said gas mixture.

Assignees

• General Electric Technology Gmbh
• Ge Infrastructure Technology Llc

Inventors

• Kieffel Yannick
• Leguizamon Cabra Diana
• Maksoud Louis
• Berteloot Thomas

Classifications

• H02B13/055 Primary

  Features relating to the gas · CPC title

• H01H2033/566

  Avoiding the use of SF6 · CPC title

• H01B3/56 Primary

  gases · CPC title

• H01H33/22 Primary

  Selection of fluids for arc-extinguishing · CPC title