High voltage electric power feed-through apparatus

Abstract

Counter effecting of local corona discharges by inside metallization of ceramic penetrator for high pressures, high temperatures and high electric voltages.

1 . An electrical feed-through apparatus for preventing or substantially reducing partial corona discharges, PD, in penetrators for high voltage supply for underwater facilities, the apparatus comprising:
 a flange of a first thickness and having an opening providing a passage between first and second oppositely located sides of said flange,   an elongated tube of a solid, electrically insulating material, and of a first length greater than said first thickness, being positioned in said passage, with first and second parts of said tube protruding from respective ones of said first and second sides of said flange,   first and second attachment sleeves positioned on said tube and being attached to respective ones of said first and second parts of said tube, at a distance from respective first and second ends of said tube, and being attached to respective ones of said first and second oppositely located sides of said flange,   an elongated electrical conductor of a second length greater than said first length, and being positioned in a lumen of said tube with first and second parts of said conductor protruding from respective ones of said first and second parts of said tube, and   a third attachment sleeve being positioned on said conductor and being attached to one of said first and second parts of said conductor, at a distance from a respective one of a first and second end of said conductor, and being attached to a respective one of a first and second end of said tube,   wherein at least a part of an inward surface of said lumen is supporting a layer of a first electrically conducting material, and the apparatus further comprising,   an electrically conducting means adapted to for establishing an electrically conducting path between said conductor and said layer of said first electrically conducting material.   
     
     
         2 . The electrical feed-through apparatus according to  claim 1 , wherein a diameter of a part of said conductor being positioned within said lumen is smaller than a diameter of said lumen so as to provide a gap between an outer surface of said conductor and an inward surface of said lumen. 
     
     
         3 . The electrical feed-through apparatus according to  claim 1 , wherein said layer of said first electrically conducting material is a layer 
     
     
         4 . The electrical feed-through apparatus according to  claim 1 , wherein said electrically conducting means is constituted by said third attachment sleeve comprising a second electrically conducting material. 
     
     
         5 . The electrical feed-through apparatus according to  claim 1 , wherein said electrically conducting means is constituted by a resilient electrical conductor positioned in a gap between an outer surface of said the conductor and an inward surface of said lumen. 
     
     
         6 . The electrical feed-through apparatus according to  claim 1 , wherein said layer of said a first electrically conducting material is provided on a longitudinal portion of said inward surface of said lumen, said longitudinal portion extending axially between about the points of attachment to said tube of said first and second attachment sleeves, respectively. 
     
     
         7 . The electrical feed-through apparatus according to  claim 1 , wherein said layer of said first electrically conducting material is provided on a longitudinal portion of said inward surface of said lumen, said the longitudinal portion extending axially beyond the points of attachment to said tube of said the first and second attachment sleeves but not entirely to ends of said tube. 
     
     
         8 . The electrical feed-through apparatus according to  claim 1 , comprising an end cap having a passage for said conductor, and being positioned at a second end of said tube located oppositely to a first end of said tube at which said third attachment sleeve is located. 
     
     
         9 . The electrical feed-through apparatus according to  claim 1 , wherein at least one of said first and second attachment sleeves is sealingly attached to said respective one of said first and second parts of said tube, and sealingly attached to said respective one of said first and second oppositely located sides of said flange, and
 said third attachment sleeve is sealingly attached to said one of said first and second parts of said conductor, sealingly attached to said respective one of a first and second end of said tube.   
     
     
         10 . An electrical feed-through apparatus for preventing or substantially reducing partial corona discharges, PD, in penetrators for high voltage supply for underwater facilities, the apparatus comprising
 a flange of a first thickness and having an opening providing a passage between first and second oppositely located sides of said flange,   an elongated tube of a solid, electrically insulating material, and of a first length greater than said first thickness, being positioned in said passage, with first and second parts of said tube protruding from respective ones of said first and second sides of said flange,   first and second attachment sleeves positioned on said tube and being attached to respective ones of said first and second parts of said tube, at a distance from respective first and second ends of said tube, and being attached to respective ones of said first and second oppositely located sides of said flange,   an elongated electrical conductor of a second length greater than said first length, and being positioned in a lumen of said tube with first and second parts of said conductor protruding from respective ones of said first and second parts of said tube, and   a third attachment sleeve being positioned on said conductor and sealingly being attached to one of said first and second parts of said conductor, at a distance from a respective one of a first and second end of said conductor, and being sealingly attached to a respective one of a first and second end of said tube, and   an end cap seal having a passage for said conductor, and being positioned in said lumen at a second end of said tube located oppositely to a first end of said tube at which said third attachment sleeve is located   wherein a space between an inward surface of said lumen and said conductor is filled with an electrically insulating liquid being resistant to high voltage breakdown.