FR2692411A1 - Sulphur hexa:fluoride gas insulated switchgear housed in enclosure - has through wall bushing with gas pressure greater than switchgear gas pressure - Google Patents

Abstract

The SF6 switchgear (1) is contained within a building (2). The gas in the switchgear is at a pressure P1. Connections are made through the wall of the building to a bushing (3) having an internal gas pressure P2 greater than P1. Between the bushing (3) and the switchgear (1) and inside the enclosure (2) is an SF6 gas filled chamber (4) whose gas pressure P3 is equal to or greater than the bushing gas pressure P2. USE/ADVANTAGE - Provides simple device for counteracting pressure loss due to temperature differences.

Description

ARMORED STATION WITH CROSSING UNDER COLD ENVIRONMENT
The invention relates to an armored crossing station in a cold environment. It concerns the installation of covered armored substations in relatively cold regions.

More precisely, it consists of an armored substation housed in a heated enclosure or which is naturally brought to a temperature higher than the outside temperature, the dielectric gas of which is at pressure P1 and the crossing of which, the dielectric gas of which is at pressure P2 greater than P1, is external
Given the large temperature difference between the outside and inside of the enclosure, despite the seals, the higher pressure dielectric gas from the crossing tends to flow into the shielded station whose gas is under pressure lower.

 The present invention proposes, by a particularly simple arrangement, to avoid this passage of gas.

 To do this, in accordance with the invention, a chamber filled with dielectric gas at a pressure P3 equal to or greater than the pressure P2 is interposed between the outlet of the crossing and the inlet of the station inside the enclosure. crossing.

 According to a preferred arrangement, in the case of a station whose dielectric gas is SF6 and whose passage contains a mixture of SF6 and nitrogen, the chamber is filled with SF6.

 The invention is set out below with the aid of a drawing representing only a preferred embodiment.

 The figure shows a view of an armored post according to the invention.

 This shielded station 1 is housed in a heated enclosure 2, for example at 25 "C. It contains a dielectric gas preferably SF6 at a pressure P1 of the order of 3.5 bars.

The crossing 3, whose dielectic gas is at a pressure
P2 higher than P1, is outside at a temperature which can go for example up to -50 "C. Preferably, this gas is a mixture of SF6 and nitrogen at partial pressures of 3 bars and therefore total pressure of 6 bars.

 Is interposed between the outlet of the crossing 3 and the entry of the station 1 inside the enclosure 2 a chamber 4 filled with dielectric gas at a pressure P3 equal to or greater than the pressure P2 of the crossing 3, preferably this gas is SF6 at a pressure for example of 6 bars.

 The chamber 4 forms a kind of plug which by the pressure of SF6 prevents the passage of the gas mixture at 6 bars from the crossing 3 to the shielded station 1, where the SF6 is at 3.5 bars. Optionally, a pressure measuring device can be mounted on the chamber 4 in order to monitor any variation thereof.

Claims (2)

 1) Armored substation (1) housed in an enclosure (2) whose dielectric gas is at a pressure P1 and whose bushing (3), whose dielectric gas is at a pressure P2 greater than P1, is external, characterized in that 'is interposed between the outlet of the bushing (3) and the inlet of the station (1) inside the enclosure (2) a chamber (4) filled with dielectric gas at a pressure P3 equal to or greater than the pressure P2 of the bushing (3).  2) Station according to claim 1 in which the dielectric gas is SF6 and in which the bushing (3) contains a mixture of SF6 and nitrogen characterized in that the chamber (4) is filled with SF6.