Apparatus and method for dynamically cooling a cable termination

Claim 2

A dynamic cable termination cooling system, comprising an electric pothead having stress controlling insulation about the cable conductor, an outer insulator about said insulation, and a low field strength region, relative to other regions of the pothead, located radially between the outer surface of said insulation and the inner surface of said outer insulator and extending generally along the length of the pothead, a flow passage within said pothead disposed entirely within said low field strength region for approximately the axial length of said stress controlling insulation and containing an insulating dielectric liquid, and means for providing an essentially closed loop for circulation of the dielectric liquid through said flow passage, said means including heat transfer means for cooling said dielectric liquid and a pump for circulating said liquid about the loop, through said flow passage and heat transfer means, said loop generally confining the circulation of the dielectric liquid to said low field strength region of the pothead for flow through said pothead along the length of the stress controlling insulation regions thereof.

Claim 3

The system of claim 1 wherein said pothead includes an annular capacitor stack concentrically arranged about said stress controlling insulation, and said flow passage is disposed in a gap between the radially outer surface of said stack and the bore wall of said outer insulator.

Claim 4

The system of claim 2 wherein said flow passage is cylindrical about the pothead axis and formed by the annulas of the gap between said outer surface of the capacitor stack and said insulator bore wall, said circulating means comprising means for conducting the dielectric liquid in only one axial direction through said passage.

Claim 5

The system of claim 1 wherein said circulating means comprises a return duct, one end of said return duct being coupled to said passage at the normally high voltage end of said pothead and the other end of said return duct being coupled to said heat transfer means, and said return duct being dispOsed external to said pothead.

Claim 6

The system of claim 4 wherein said return duct comprises an insulator column.

Claim 7

The system of claim 1 wherein said pothead comprises a hollow body section at the normally grounded end thereof adjacent an end of said outer insulator, said liquid circulating means being coupled to said body section for flowing the dielectric liquid therethrough, and a manifold disposed between said body section and said flow passage to promote a uniform flow through said passage.

Claim 8

The system of claim 6 wherein said pothead comprises an additional manifold at the other end of said flow passage to promote a uniform flow through said passage.

Claim 9

The system of claim 6 wherein said flow passage comprises a plurality of separate ducts, and said manifold comprises means for passing flow in one axial direction in one of said ducts and in the opposite direction from another of said ducts.

Claim 10

The system of claim 6 wherein said pothead comprises an additional manifold at the other end of said ducts for receiving the dielectric liquid flow in one axial direction and discharging the dielectric liquid flow in the opposite axial direction through respective ones of said ducts.

Claim 11

The system of claim 1 wherein said liquid circulating means comprises filtering means for maintaining the dielectric qualities of said insulating liquid.

Claim 12

The system of claim 1 for use with an insulating liquid filled pipe-type cable system, comprising means communicating between said pothead body and the pipe cable system for maintaining the insulating liquid under a pressure approximately equal to that of the liquid within the pipe.

Claim 13

The system of claim 1 wherein said circulation loop is confined generally to said cable termination.

Claim 16

The method of claim 13 wherein said pothead comprises stress controlling insulation and an outer insulator, and said recirculating insulating liquid is passed between the stress controlling insulation and the outer insulator of said pothead.

Claim 17

The method of claim 14 wherein the insulating liquid is circulated through said pothead in only one axial direction.

Claim 18

The method of claim 15 wherein the insulating liquid is fed into said pothead at its normally grounded end and discharged from said pothead at its normally high voltage end.

Claim 19

The method of claim 14 wherein the insulating liquid is circulated through said pothead in opposite axial directions.

Claim 20

The method of claim 17 wherein half of the total insulating liquid flow is in each axial direction, and the insulating liquid is fed into and discharged from said pothead at its normally grounded end.

Claim 21

A dynamic cable termination cooling system comprising: a high voltage pothead having an outer cylindrical insulator and inner stress controlling insulation within said outer insulator disposed about a central conductor defining the axis of the pothead, terminal means disposed at one end of said insulator and electrically connected to said central conductor, a hollow conductive body affixed to the other end of said insulator and disposed about said conductor in insulated relation thereto, means for providing a liquid-tight seal at the entrance of said conductor to said body and between said one end of said insulator and said terminal means, a liquid flow passage located between said insulation and said outer insulator, said Passage communicating at said other end of said insulator with the interior space defined by said terminator body, and means coupled to one end of said passage and to said body for defining a loop for circulating an insulating liquid therethrough, said loop being generally confined to said cable termination and including said passage and body, heat transfer means for removing heat from said liquid, and a pump for circulating said liquid about said loop.

Claim 22

A dynamic cable termination cooling system comprising: a high voltage pothead having an outer cylindrical insulator and inner stress controlling insulation within said outer insulator disposed about a central conductor defining the axis of the pothead, terminal means disposed at one end of said insulator and electrically connected to said central conductor, a hollow conductive body affixed to the other end of said insulator and disposed about said conductor in insulated relation thereto, means for providing a liquid-tight seal at the entrance of said conductor to said body and between said one end of said insulator and said terminal means, a liquid flow passage located between said insulation and said outer insulator, said Passage communicating at said other end of said insulator with the interior space defined by said terminator body, and means coupled to one end of said passage and to said body for defining a loop for circulating an insulating liquid therethrough, said loop being generally confined to said cable termination and including said passage and body, heat transfer means for removing heat from said liquid, and a pump for circulating said liquid about said loop.

Claim 23

The system of claim 19 wherein said means comprises means for maintaining the dielectric qualities of said insulating liquid.

Claim 24

A dynamic cable termination cooling system comprising: a high voltage pothead having an outer cylindrical insulator and inner stress controlling insulation within said outer insulator disposed about a central conductor defining the axis of the pothead, terminal means disposed at one end of said insulator and electrically connected to said central conductor, a hollow conductive body affixed to the other end of said insulator and disposed about said conductor in insulated relation thereto, means for providing a liquid-tight seal at the entrance of said conductor to said body and between said one end of said insulator and said terminal means, a liquid flow passage located between said insulation and said outer insulator, said passage communicating at said other end of said insulator with the interior space defined by said terminator body, cooling means coupled to one end of said passage and to said body for circulating an insulating liquid through said passage and body, said cooling means including a pump and heat transfer means for removing heat from said liquid, means for dividing said liquid flow passage into a plurality of separate axial ducts, and manifold means for causing the insulating liquid to flow in one axial direction in one of said ducts and in the opposite axial direction in another of said ducts.

Claim 25

A dynamic cable termination cooling system comprising: a high voltage pothead having an outer cylindrical insulator and inner stress controlling insulation within said outer insulator disposed about a central conductor defining the axis of the pothead, terminal means disposed at one end of said insulator and electrically connected to said central conductor, a hollow conductive body affixed to the other end of said insulator and disposed about said conductor in insulated relation thereto, means for providing a liquid-tight seal at the entrance of said conductor to said body and between said one end of said insulator and said terminal means, a liquid flow passage located between said insulation and said outer insulator, said passage communicating at said other end of said insulator with the interior space defined by said terminator body, cooling means coupled to one end of said passage and to said body for circulating an insulating liquid through said passage and body, said cooling means including a pump and heat transfer means for removing heat from said liquid, means for dividing said liquid flow passage into a plurality of separate axial ducts, and manifold means for causing the insulating liquid to flow in one axial direction in one of said ducts and in the opposite axial direction in another of said ducts.

Claim 26

The system of claim 21 wherein said manifold means comprises a first manifold disposed between said hollow pothead body and selected ones of said ducts to permit liquid flow toward said one end of said passage, and a second manifold disposed at said one end of said passage to permit liquid flow toward said body through selected others of said ducts.

Claim 27

The system of claim 22 wherein said first manifold comprises means for receiving the liquid flow from said selected other of said ducts and discharging the same into said body.

Claim 28

A dynamic cable termination cooling system comprising: a high voltage pothead having an outer cylindrical insulator and inner stress controlling insulation within said outer insulator disposed about a central conductor defining the axis of the pothead, terminal means disposed at one end of said insulator and electrically connected to said central conductor, a hollow conductive body affixed to the other end of said insulator and disposed about said conductor in insulated relation thereto, means for providing a liquid-tight seal at the entrance of said conductor to said body and between said one end of said insulator and said terminal means, a liquid flow passage located between said insulation and said outer insulator, said passage communicating at said other end of said insulator with the interior space defined by said terminator body, cooling means coupled to one end of said passage and to said body for circulating an insulating liquid through said passage and body, said cooling means including a pump and heat transfer means for removing heat from said liquid, and a duct external to said pothead coupled between said one end of said flow passage and said heat transfer means.

Claim 29

A dynamic cable termination cooling system comprising: a high voltage pothead having an outer cylindrical insulator and inner stress controlling insulation within said outer insulator disposed about a central conductor defining the axis of the pothead, terminal means disposed at one end of said insulator and electrically connected to said central conductor, a hollow conductive body affixed to the other end of said insulator and disposed about said conductor in insulated relation thereto, means for providing a liquid-tight seal at the entrance of said conductor to said body and between said one end of said insulator and said terminal means, a liquid flow passage located between said insulation and said outer insulator, said passage communicating at said other end of said insulator with the interior space defined by said terminator body, cooling means coupled to one end of said passage and to said body for circulating an insulating liquid through said passage and body, said cooling means including a pump and heat transfer means for removing heat from said liquid, and a duct external to said pothead coupled between said one end of said flow passage and said heat transfer means.

Claim 30

The system of claim 24 wherein said pump discharges the cooled insulating liquid from said heat transfer means to said pothead body, and said external duct conducts the heated insulating liquid from said pothead to said heat transfer means.

Claim 31

The system of claim 24 wherein said external ducT comprises an insulator column.

Claim 32

A dynamic cable termination cooling system for use with an oil filled pipe-type cable system, comprising a high voltage pothead having an outer cylindrical insulator and inner stress controlling insulation within said outer insulator disposed about a central conductor defining the axis of the pothead, terminal means disposed at one end of said insulator and electrically connected to said central conductor, a hollow conductive body affixed to the other end of said insulator and disposed about said conductor in insulated relation thereto, means for providing a liquid-tight seal at the entrance of said conductor to said body and between said one end of said insulator and said terminal means, a liquid flow passage located between said insulation and said outer insulator, said passage communicating at said other end of said insulator with the interior space defined by said terminator body, cooling means coupled to one end of said passage and to said body for circulating an insulating liquid through said passage and body, said cooling means including a pump and heat transfer means for removing heat from said liquid, and means communicating between said pothead body and the pipe cable system to maintain the insulating liquid under a pressure approximately equal to that of the pipe cable oil.

Claim 33

A dynamic cable termination cooling system for use with an oil filled pipe-type cable system, comprising a high voltage pothead having an outer cylindrical insulator and inner stress controlling insulation within said outer insulator disposed about a central conductor defining the axis of the pothead, terminal means disposed at one end of said insulator and electrically connected to said central conductor, a hollow conductive body affixed to the other end of said insulator and disposed about said conductor in insulated relation thereto, means for providing a liquid-tight seal at the entrance of said conductor to said body and between said one end of said insulator and said terminal means, a liquid flow passage located between said insulation and said outer insulator, said passage communicating at said other end of said insulator with the interior space defined by said terminator body, cooling means coupled to one end of said passage and to said body for circulating an insulating liquid through said passage and body, said cooling means including a pump and heat transfer means for removing heat from said liquid, and means communicating between said pothead body and the pipe cable system to maintain the insulating liquid under a pressure approximately equal to that of the pipe cable oil.