SF6 free gas insulated disconnector with limited arcing volume
A disconnector for a GIS, including a pair of permanent contacts, one fixed and the other one movable along an axis, called the axis of the disconnector, a pair of arcing contacts, one fixed and the other one movable, an insulating part located inside the fixed arcing contact, means for pressing the insulating part against a front surface of the movable arcing contact, and an insulating ring located at the outlet of the fixed arcing contact.
1 . A disconnector for a Gas-Insulated Substation (GIS), comprising:
a pair of permanent contacts, one fixed and the other one movable along an axis, called the axis of the disconnector;
a pair of arcing contacts, one fixed and the other one movable;
an insulating part located inside the fixed arcing contact, and a spring configured for pressing the insulating part against a front surface of the movable arcing contact;
an insulating ring located at an outlet of the fixed arcing contact; and
wherein, when the pair of arcing contacts separate, the pair of arcing contacts form, together with the insulating part and the insulating ring, a limited volume which contains a limited quantity of gas.
2 . The disconnector according to claim 1 , the insulating ring having an internal restriction.
3 . The disconnector according to claim 1 , the insulating ring having a V-shaped section in a plane containing the axis.
4 . The disconnector according to claim 3 , the insulating ring extending along the axis between a front face which faces the fixed arcing contact and an opposite back face and an opposite back face internal surface having a restriction between both ends.
5 . The disconnector according to claim 4 , the internal surface having a first slope which is inclined in a first direction from the front face to the restriction and then a second slope which is inclined in an opposite direction from the restriction to the back face.
6 . The disconnector according to claim 5 , the second slope being inclined with an angle comprised between 50° and 10° with respect to the axis of a circuit breaker.
7 . The disconnector according to claim 1 , a front end of the fixed arcing contact having a concave portion.
8 . The disconnector according to claim 1 , a front end of the fixed arcing contact having a stair step shape.
9 . The disconnector according to claim 1 , at least part of the insulating part located inside the fixed arcing contact having a shape of a disk or of a cylinder.
10 . A GIS comprising:
metal tank filled with a gas;
the disconnector according to claim 1 .
11 . The GIS according to claim 10 , the gas comprising SF 6 , or heptafluoroisobutyronitrile and/or heptafluoroisopropyl trifluoromethyl ketone (also named 2-butanone, 1,1,1,3,4,4,4-heptafluoro-3-(trifluoromethyl)-(CAS No 756-12-7)) and/or CO 2 and/or O 2 and/or N 2 and/or an oxygenated compounds, comprising both CO 2 and a fluorinated compound.
12 . A method for opening the disconnector of the GIS according to claim 10 , comprising:
moving the movable arcing contact and a movable main contact with respect to the fixed arcing contact and a fixed main contact, thereby opening the movable main contact and closing the pair of arcing contacts, and pressing the insulating part located inside the fixed arcing contact against a front surface of the movable arcing contact;
separating the pair of arcing contacts from each other, thereby triggering an arc between the pair of arcing contacts, in a volume limited by the pair of arcing contacts and by both the insulating part and the insulating ring.
13 . A disconnector for a Gas-Insulated Substation (GIS), comprising:
a pair of permanent contacts, one fixed and the other one movable along an axis, called the axis of the disconnector;
a pair of arcing contacts, one fixed and the other one movable;
an insulating part located inside the fixed arcing contact, and a spring configured for pressing the insulating part against a front surface of the movable arcing contact;
an insulating ring located at an outlet of the fixed arcing contact;
the insulating ring having an internal diameter equal to or smaller than, an internal diameter of the fixed arcing contact.
14 . A disconnector for a Gas-Insulated Substation (GIS), comprising:
a pair of permanent contacts, one fixed and the other one movable along an axis, called the axis of the disconnector;
a pair of arcing contacts, one fixed and the other one movable;
an insulating part located inside the fixed arcing contact, and a spring configured for pressing the insulating part against a front surface of the movable arcing contact;
an insulating ring located at an outlet of the fixed arcing contact;
the insulating part located inside the fixed arcing contact comprising a stopping member cooperating with a stopping member of the fixed arcing contact to block movement of the insulating part under action of the spring pressing the insulating part against a front surface of the movable arcing contact.