EP-4738410-A1 - AN ELECTRIC ARC INTERRUPTION ARRANGEMENT

EP4738410A1EP 4738410 A1EP4738410 A1EP 4738410A1EP-4738410-A1

Abstract

An electric arc interruption arrangement (100) comprising: a chamber (110) having an inlet (112) facing towards an arc zone (107), an electrically insulating and movable barrier (108) arranged to move from a first position to a second position, wherein in the second position the electrically insulating and movable barrier (108) splits the arc zone (107) and is positioned at least partly in the chamber, a resiliently deformable seal (114) arranged in a side wall in the chamber to contact and seal against the electrically insulating and movable barrier in its second position to interrupt an arc path between two electrical contacts (104, 106).

Inventors

MANNEKUTLA, James
VIERTEL, Julia
NOHLERT, Johan
ERIKSSON, THOMAS
Becerra, Marley
BERGAMINI, ALESSIO

Assignees

ABB SCHWEIZ AG

Dates

Publication Date: 20260506
Application Date: 20241029

Claims (15)

An electric arc interruption arrangement (100) comprising: a chamber (110) having an inlet (112) facing towards an arc zone (107), an electrically insulating and movable barrier (108) arranged to move from a first position to a second position, wherein in the second position the electrically insulating and movable barrier (108) splits the arc zone (107) and is positioned at least partly in the chamber, a resiliently deformable seal (114) arranged in a side wall in the chamber to contact and seal against the electrically insulating and movable barrier in its second position to interrupt an arc path between two electrical contacts (104, 106).
The electric arc interruption arrangement according to claim 1, wherein the resiliently deformable seal comprises a base end (120) supported in the side wall and a free end (122) configured to protrude into the chamber.
The electric arc interruption arrangement according to claim 2, wherein the free end is movable relative the base end.
The electric arc interruption arrangement according to any one of claims 2-3, wherein the resiliently deformable seal comprises a gas pocket (126) between the free end and the base end configured such that a gas pressure build up in the gas pocket cause the free end (122) to move in the chamber (110).
The electric arc interruption arrangement according to claim 4, wherein the motion of the electrically insulating and movable barrier into the chamber cause the pressure build up in the gas pocket.
The electric arc interruption arrangement according to any one of the preceding claims, comprising multiple resiliently deformable seals at different distances into the chamber from the inlet.
The electric arc interruption arrangement according to any one of the preceding claims, wherein the seal has a substantially U-shaped portion.
The electric arc interruption arrangement according to any one of the preceding claims, wherein the seal comprises an inclined surface (136) configured to engage with the barrier when it moves towards the second position.
The electric arc interruption arrangement according to any one of the preceding claims, wherein the chamber and the barrier are tubular and the seal is annular.
The electric arc interruption arrangement according to any one of the preceding claims, wherein the seal is arranged in an opening in the side wall of the chamber, the opening comprising an inner groove (140) in which a fixing portion (142) of the seal is mounted to fixate the seal.
The electric arc interruption arrangement according to any one of the preceding claims, wherein the seal in configured to reshape to its initial shape when the barrier has moved back to its first position.
The electric arc interruption arrangement according to any one of the preceding claims, wherein the resiliently deformable seal is made from a polymeric material.
The electric arc interruption arrangement according to claim 12, wherein the polymeric material has arc-quenching properties and is configured to withstand the temperature during arc-quenching..
The electric arc interruption arrangement according to any one of the preceding claims, wherein the movable barrier is configured to push the arc into the chamber.
The electric arc interruption arrangement according to any one of the preceding claims, wherein the electrically insulating and movable barrier is configured with a tapered leading edge (138) that gradually engages with the seal.

Description

Field of the Invention The present invention relates to an electric arc interruption arrangement. Background Electrical switching devices, such as circuit breakers and disconnect switches, are widely used in power distribution and electrical systems to control and interrupt electrical currents. These electrical switching devices are importantly able to interrupt fault currents and protect the electrical system from damage caused by overcurrent or short circuits. During the interruption of high fault currents, an electric arc forms between the contacts of the electrical switching device. This arc can generate significant heat and damage the components of the switching device if not properly controlled or extinguished. Summary In view of the above-mentioned and other drawbacks of the prior art, it is an object of the present invention to provide an electric arc interruption arrangement that at least partly alleviates the deficiencies with prior art. According to a first aspect of the invention, there is provided an electric arc interruption arrangement comprising: a chamber having an inlet facing towards an arc zone, an electrically insulating and movable barrier arranged to move from a first position to a second position, wherein in the second position the electrically insulating and movable barrier splits the arc zone and is positioned at least partly in the chamber, a resiliently deformable seal arranged in a side wall in the chamber to contact and seal against the electrically insulating and movable barrier in its second position to interrupt an arc path between two electrical contacts. The present invention is at least partly based on the realization of a seal that squeezes the arc against the insulating barrier to cut off the arc. Furthermore, the resilient deformable seal provides for compensating for the gap between the insulating barrier and the side wall in the chamber even in the event of minor erosion of the seal or insulating barrier due to natural material losses. The resilient deformable seal provides for an efficient seal between the movable insulating barrier and the side wall of the chamber, even considering that the insulating barrier is movable relative to the side wall. The arc zone is the area or volume or location where the arc is formed and from which the electrically insulation barrier pushes the arc into the chamber. The seal may be arranged in an opening which may be a groove or trench that accommodates the seal. Part of the seal can protrude into the chamber such that it contacts the electrically insulation barrier when it moves in the chamber. The seal may equally well be stacked with side wall partitions that jointly form an outer side wall of the chamber In one embodiment, the resiliently deformable seal comprises a base end supported in the side wall and a free end configured to protrude into the chamber. The free end is movable relative to the base end which is fixated in in the side wall of the chamber, for example in an opening of the side wall. The free end flexes into the chamber. This advantageously provides for an efficient seal that can account for erosion in the chamber and/or the electrically insulation barrier. That motion of the flexing may be in a radially inwards direction in a cylindrical geometry of the chamber. In one embodiment, the resiliently deformable seal may comprise a gas pocket between the free end and the base end configured such that a gas pressure build-up in the gas pocket cause the free end to move into the chamber. When the movable electrically insulating barrier moves into and push the arc into the chamber and reaches the height where the seal is located, the free end of the seal partially blocks a gap on the side of the electrically insulating barrier. The pressure build-up in the gas pocket pushes the free end towards the electrically insulating barrier to close the gap. Advantageously, the seal take advantage of the pressure gradient in the chamber to seal against the electrically insulating barrier, providing for a self-activated seal. In other words, the motion of the electrically insulating and movable barrier into the chamber advantageously causes the pressure build up in the gas pocket which consequently cause the seal to close the gap. In one embodiment, the electric arc interruption arrangement may comprise: multiple resiliently deformable seals at different distances into the chamber from the inlet. In this way, a more efficient sealing is provided. The seals may be arranged in parallel at different distances into the chamber. In one embodiment, the seal has a substantially U-shaped portion. In one embodiment, the seal may comprise an inclined surface configured to engage with the electrically insulating barrier when it moves towards the second position. The inclined surface provides for more controlled force transfer between the seal and the electrically insulating barrier that reduces the risk of damaging the seal and instead pushin