Gas insulated electrical equipment

Patent metadata

Field	Value
Publication number	US-9508507-B2
Application number	US-201314437932-A
Country	US
Kind code	B2
Filing date	Oct 17, 2013
Priority date	Dec 21, 2012
Publication date	Nov 29, 2016
Grant date	Nov 29, 2016

Abstract

Gas insulated electrical equipment includes: a metal enclosure having an insulating gas introduced therein; a conductor that is accommodated inside the metal enclosure and to which voltage is applied; and an insulating and supporting member insulating and supporting the conductor relative to the metal enclosure. The conductor is circumferentially covered with a dielectric film, and furthermore, a nonlinear resistance film provided on the dielectric film and having a nonlinear volume resistivity decreasing when the nonlinear resistance film is acted on by an electric field higher than a critical value.

First claim

The invention claimed is:

1. Gas insulated electrical equipment comprising:
a metal enclosure having an insulating gas introduced therein;
a conductor that is accommodated inside said metal enclosure and to which voltage is applied; and
an insulating and supporting member insulating and supporting said conductor relative to said metal enclosure,
said conductor having a circumferential surface on which is provided a dielectric film, and a nonlinear resistance film provided on said dielectric film and having a nonlinear volume resistivity decreasing when said nonlinear resistance film is acted on by an electric field higher than a critical value.

2. The gas insulated electrical equipment according to claim 1 , wherein said nonlinear resistance film is smaller in thickness than said dielectric film, and said nonlinear resistance film has a dimension in thickness smaller than a distance from an internal surface of said metal enclosure to a surface of said nonlinear resistance film.

3. The gas insulated electrical equipment according to claim 1 , wherein said nonlinear resistance film is provided to be constant in volume resistivity in an electric field equal to or lower than a testing electric field and decrease in volume resistivity in an electric field higher than said testing electric field, said testing electric field being an electric field acting on said nonlinear resistance film when a test voltage is applied to confirm whether said metal enclosure has any metallic particle therein.

4. The gas insulated electrical equipment according to claim 1 , wherein:
said nonlinear resistance film is formed of a binder resin used for providing said film, and a nonlinear resistance material; and
said binder resin has a major component identical to that of said dielectric film.

5. The gas insulated electrical equipment according to claim 1 , wherein said metal enclosure has an inner circumference covered with a dielectric film and a nonlinear resistance film provided on said dielectric film and having a nonlinear volume resistivity decreasing when said nonlinear resistance film is acted on by an electric field higher than a critical value.

6. The gas insulated electrical equipment according to claim 1 , wherein:
said conductor includes a horizontally disposed horizontal portion and a vertically disposed vertical portion; and
said dielectric film and said nonlinear resistance film are provided on said conductor only at said horizontal portion.

Assignees

• Mitsubishi Electric Corp

Inventors

• Yoshimura Manabu
• Miyamoto Takashi
• Kainaga Soichiro
• Mori Tsuyoshi
• Sadakuni Hitoshi

Classifications

• H01H2223/002

  sealed · CPC title

• H01H33/24

  Means for preventing discharge to non-current-carrying parts, e.g. using corona ring · CPC title

• H01H33/53

  Cases (for switchgear H02B1/26); Reservoirs, tanks, piping or valves, for arc-extinguishing fluid; Accessories therefor, e.g. safety arrangements, pressure relief devices · CPC title

• H02B13/065

  Means for detecting or reacting to mechanical or electrical defects · CPC title

• H02G5/06 Primary

  Totally-enclosed installations, e.g. in metal casings · CPC title