Electrical cable limiting partial discharges

Patent metadata

Field	Value
Publication number	US-11948705-B2
Application number	US-202117466552-A
Country	US
Kind code	B2
Filing date	Sep 3, 2021
Priority date	Sep 4, 2020
Publication date	Apr 2, 2024
Grant date	Apr 2, 2024

Abstract

An insulated electrically conductive element (1) for the aerospace field, has an elongate electrically conductive element surrounded by at least two layers. The two layers are being an electrically insulating layer (4) surrounding the elongate electrically conductive element (2) and a first semiconductor layer (5) surrounding the electrically insulating layer (4). At least one of the layers has having at least one fluoropolymer.

First claim

The invention claimed is:

1. An insulated electrically conductive element limiting the occurrence of partial discharges, comprising:
an elongate electrically conductive element surrounded by a tri-layer insulation system comprising
at least one electrically insulating layer surrounding the elongate electrically conductive element,
at least a first semiconductor layer of a thickness e 1 surrounding said electrically insulating layer, and
a third layer, said third layer being a second semiconductor layer of a thickness e 2 surrounding the elongate electrically conductive element, and being placed between the elongate electrically conductive element and the electrically insulating layer, the first semiconductor layer, the electrically insulating layer and the second semiconductor layer constituting said tri-layer insulation system,
wherein said electrically insulating layer has a thickness the value of said thickness e i being determined according to the operating voltage U of the insulated electrically conductive element, the value of the electric field e max , and an inner diameter d 1 of the electrically insulating layer,
wherein the thickness e i of the insulating layer is determined according to a ratio of the operating voltage U to the diameter d 1 , such that the thickness e i simultaneously satisfies the following relationship:
ei ≥ d 1 2 [ exp ( U E max × d 1 2 ) - 1 ] and
the thickness el≥e 1+ e 2.

2. The element according to claim 1 , wherein the minimum value of the thickness e is determined according to a following relationship R1:

R
⁢

⁢
1

=

U

E
max

×

d
1

2

U being expressed in kilovolts (kV),
E max being the maximum value of the electric field that may be applied to the insulation layer and being expressed in kilovolts/mm, and
the diameter d 1 being expressed in millimetres (mm).

3. The element according to claim 1 , wherein the minimum value of the thickness e is determined according to a following expression E1:

E
⁢

⁢
1

=

exp
(

U

E
max

×

d
1

2

)

-
1

4. The element according to claim 1 , wherein the maximum value of the thickness e i is determined according to a following relationship R2:

R
⁢

⁢
2

=

3
×
U

E
max

×

d
1

2

5. The element according to claim 1 , wherein the maximum value of the thickness e i is determined according to a following expression E2:

E
⁢

⁢
2

=

exp
(

3
×
U

E
max

×

d
1

2

)

-
1

6. The element according to claim 1 , wherein the thickness e i satisfies the following relationship:

ei
≤

d
1

2

[

exp
(

3
×
U

E
max

×

d
1

2

)

-
1

]

7. The element according to claim 1 , wherein at least one of the insulation layer, the first semiconductor layer and the second conductor layer comprises at least one fluoropolymer.

8. The element according to claim 1 , wherein each of the insulation layer, the first semicondcutor layer and the second semicondcutor layer comprises at least one fluoropolymer.

9. The element according to claim 1 , wherein the fluoropolymer is chosen from the copolymers obtained from tetrafluorethylene monomer, and in particular polytetrafluorethylene (PTFE); fluorinated ethylene and propylene (FEP) copolymers such as, for example, poly(tetrafluoroethylene-co-hexafluoropropylene); perfluoroalkoxy alkane (PFA) copolymers such as, for example, perfluoro(alkyl vinyl ether)/tetrafluoroethylene copolymers; perfluoromethoxy alkane (MFA) copolymers; and ethylene tetrafluoroethylene (ETFE); or one of the mixtures thereof.

10. An electrically conductive cable, said electrically conductive cable comprising: at least one insul

Assignees

• Nexans

Inventors

• Hahner Thomas
• Rybski Patrick
• Charrier Dimitri
• Charmetant Adrien
• Lagomarsini Clara
• Mellouky Nabil
• Paixao Dantas Marcelo

Classifications

• H01B7/0208 Primary

  Cables with several layers of insulating material · CPC title

• H01B1/124

  Intrinsically conductive polymers · CPC title

• H01B9/027 Primary

  composed of semi-conducting layers · CPC title

• H01B7/02 Primary

  Disposition of insulation · CPC title

• H01B7/17

  Protection against damage caused by external factors, e.g. sheaths or armouring · CPC title