JP2018527873A - Change joint - Google Patents

Abstract

The modified joint connects the oil-filled cable and the solid insulated cable and includes a connector, a glass fiber tube (210), a pre-made joint body (108, 228) and a copper housing (106). A glass fiber tube (210) surrounds the end of the oil-filled cable (102, 220). A pre-made joint body (108, 228) surrounds the first deflector (214), the second deflector (215) and the high voltage (HV) electrode (316). To form the outermost layer of the modified joint (100, 200), the copper housing (106) surrounds a pre-made joint body. Changed joints, including pre-made joint bodies, are smaller in size, but the time to connect the two types of cables using the changed joint is reduced.

Description

  The present invention relates to a change joint for connecting an oil-filled cable and a solid insulated cable.

  Oil-filled high voltage power cables have been used since the 1920s and their performance is very satisfactory. Solid insulated power cables have been developed since the 1980s and are gradually being replaced by oil-filled cables. Various modification joints are used to connect oil-filled cables and solid insulated cables. Using conventional useful modification joints for connecting oil-filled cables and solid insulated cables may not be easy and efficient.

  In view of the requirement to efficiently connect these two types of power cables, an improved modified joint is desired.

FIG. 1 illustrates a modified joint according to one embodiment. FIG. 2 shows a longitudinal view of a modified joint according to one embodiment. FIG. 3 shows a pre-made joint body of a modified joint according to one embodiment. FIG. 4 shows a modified joint glass fiber tube according to one embodiment.

  One embodiment is a modified joint that connects an oil-filled cable and a solid insulated cable. The modified joint includes a connector, a glass fiber tube, a pre-made joint body and a copper housing. The connector secures the end of the oil-filled cable and the end of the solid insulated cable to form a modified joint core. The glass fiber tube capped with a metal cap at the first end is inserted into the end of the oil-filled cable at the second end, and surrounds the end of the oil-filled cable inside the change joint. A pre-made joint body surrounds the first deflector at the tapered first end and surrounds the second deflector at the tapered second end and surrounds the high voltage (HV) electrode in the middle section. The copper housing surrounds a pre-made change body to form the outermost layer of the change joint.

  Other embodiments are discussed herein.

  Embodiments relate to instruments and methods for connecting oil-filled cables and solid-insulated cables including pre-made joint bodies and modified joints including glass fiber tubes. The glass fiber tube acts as an insulator to separate the oil-filled cable from the pre-made joint body and other parts of the modified joint.

  Paper insulated oil-filled cables have been used as high-voltage power cables since the 1920s, and the performance of oil-filled cables has been sufficiently satisfied. Users have faced difficulties in using oil-filled cables due to complicated technology, high skill demands to connect oil-filled cables, and oil leaks after prolonged extended use periods . In the case of an oil leak, continuous pumping of oil to ground is necessary to maintain operation of the oil-filled cable. This causes environmental pollution.

  Solid insulation cables have been gradually replaced by oil-filled cables since the 1980s, as attaching solid insulation cables is simpler and user friendly. In this respect, production facilities for oil-filled cables are also decreasing. Oil-filled cables are now being used for excessively high voltage cables or submarine cables with voltage loads that gradually exceed 220 kV.

  The service life of power cables ranges from 30 to 50 years or more, and oil-filled cables are still operating satisfactorily, so if a healthy circuit using oil-filled cables is scrapped, it is a waste of resources right. For this reason, a modified joint was developed to connect existing oil-filled cables and newly installed solid insulated cables.

In general, the structure of a conventional change joint is as follows. Stop joint technology for oil-filled cables with two insulators on the back inside the container;
2.2 Pre-manufactured joint technology for solid insulated cables that use epoxy resin elements to connect different types of cables and require a compression unit and stress cone on one side and a paper stress cone on the oil-filled cable side.
3. A straight connection with an O-ring is used to prevent the oil forming the oil-filled cable from separating and penetrating into the solid insulated cable side.

  Conventional change joints are large and cumbersome, and the use of conventional change joints to connect these two types of cables is complex and time consuming.

  One embodiment includes a simplified approach of using a specially designed pre-made joint body that covers both oil-filled cables and solid insulated cables. In one embodiment, the modified joint, including the pre-made joint body, is reduced in size while reducing the time to connect the two types of cables using the modified joint.

  In one embodiment, the pre-made joint body can control the electric field inside the modified joint. In other embodiments involving the use of pre-made joint bodies, the main parts of the modified joint can be factory tested and such a test routine is similar to other XLPE cable joints. Therefore, the reliability of the change joint installation is greatly improved.

  According to an embodiment aspect, the length of the modified joint is significantly reduced. According to one embodiment, the modified joint is about half as long as a conventional modified joint. According to one embodiment, the mounting of the change joint is simple and fast.

  According to one embodiment, the modified joint passes an internal development high voltage alternating current (HVAC) test at the required 132 kV voltage level under thermal cycling and impact.

  One embodiment includes a system in which an oil-filled cable is connected to a solid insulated cable. The system includes a solid metal connector, a cavity insulator, an electric field controller, a silicone rubber joint body, and a copper sleeve. The solid metal connector fixes the end of the oil-filled cable and the end of the solid insulated cable to form a core. The cavity insulator connects to the solid metal connector at the first end and is inserted into the end of the oil-filled cable at the second end, and the cavity insulator concentrically surrounds the end of the oil-filled cable inside the system. The electric field controller concentrically surrounds the cavity insulator and solid metal connector and controls the electric field within the system. The silicone rubber joint body concentrates the electric field controller. The copper sleeve is concentric and surrounds the silicone rubber joint body.

  In one embodiment, the electric field controller includes a first deflector that is concentrically enclosed within a silicone rubber joint body. The first deflector concentrically surrounds the cavity insulator at the first end of the silicone rubber joint body.

  In other embodiments, the electric field controller includes a second deflector that is concentrically enclosed within the silicone rubber joint body. The second deflector concentrically surrounds the cavity insulator at the first end of the silicone rubber joint body.

  In one embodiment, the electric field controller includes a high voltage (HV) electrode that concentrically surrounds the core.

  In one embodiment, the electric field controller concentrically surrounds the first end of the cavity insulator.

  According to an embodiment aspect, the cavity insulator is made of glass fiber.

  In one embodiment, the system includes a T-shaped intermediate flange and a bottom flange. For securing to a copper sleeve having a cavity insulator, a T-shaped intermediate flange and a bottom flange are disposed at the first end of the copper sleeve and abut against the second end of the cavity insulator.

  In one embodiment, the cavity insulator is secured to the silicone rubber joint body with epoxy resin at the second end of the cavity insulator.

  FIG. 1 illustrates a modified joint 100 that connects an oil-filled cable 102 and a solid insulated cable 104 according to one embodiment. The portion of the change joint 100 where the change joint 100 connects to the oil-filled cable 102 is encased by a copper housing 106 as shown in the embodiment of FIG. In this way, some elements of the change joint 100 required for connection with the oil-filled cable are not shown in FIG. The copper housing 106 forms the outermost layer of the change joint 100 and protects the change joint 100 from insulation. In one embodiment, the copper housing 106 surrounds the entire modified joint.

  In one embodiment, the oil-filled cable has a voltage load of at least 110 kV. According to an embodiment aspect, the oil-filled cable has a voltage load of 132 kV.

  In one embodiment, the solid insulated cable is made of cross-linked polyethylene (XPLE) and has a voltage load of at least 110 kV. According to an embodiment aspect, the solid insulated cable has a voltage load of 132 kV.

  The modified joint 100 includes a deflector 110 that is located directly around the portion of the pre-made joint body 108 and solid insulated cable 104 that are narrowed at both ends, directly below the copper housing 106. The pre-made joint body 108 is made of a sufficiently tensioned elastic material so that it can provide support for the change joint 100 without using a support element such as a compression unit within the change joint 100.

  According to an embodiment aspect, the pre-made joint body 108 is made of silicone rubber. According to another embodiment, the pre-made joint body 108 is made of ethylene-propylene rubber (EPR).

  According to one embodiment, the modified joint 100 passes an internal development high voltage alternating current (HVAC) test at the required 132 kV voltage level under thermal cycling and impact.

  FIG. 2 shows a modified joint 200 that connects the oil-filled cable 202 and the solid insulated cable 204 as in the embodiment. The change joint 200 has a tapered shape at both ends, and has a cylindrical shape. The modified joint 200 includes a connector 206, a glass fiber tube 210, a high voltage (HV) electrode 212, a first deflector 214, a second deflector 215, and a pre-made joint body 216. The copper housing 218 serves as the outermost layer of the change joint 200.

  In one embodiment, the oil-filled cable end 220 includes a head section 220A and a tail section 220B. In other embodiments, the end of the solid insulated cable 222 includes a head section 222A and a tail section 222B.

  Connector 206 includes oil-filled cable end 220 and solid-insulated cable end 222 to form a modified joint core so that oil-filled cable 202 mechanically and electrically connects to solid-insulated cable 204. Secure to.

  In one embodiment, oil-filled cable connector 230 connects oil-filled cable end 220 and connector 206 so that oil-filled cable 202 securely connects to connector 206. The uneven support tube 232 is fitted into the oil-filled cable conductor 230 in order to maintain the oil path inside the oil-filled cable 202. In one embodiment, the concavo-convex support tube 232 is made of stainless steel.

  The glass fiber tube 210 is capped with a connector 206 at the first end 252. The glass fiber tube 210 is inserted at the second end 254 onto the oil-filled cable end 220 and surrounds the oil-filled cable 220 end. In one embodiment, the glass fiber tube 210 is secured to the pre-made joint body 216 at the second end 254 with epoxy resin. The glass fiber tube 210 separates the oil-filled cable 220 from the change joint 200 and prevents oil inside the oil-filled cable 202 from spilling and leaking to the change joint 200. In one embodiment, the glass fiber tube 210 is oil-coated for the pre-made joint body 216 to protect the pre-made joint body 216 from any oil contact that may leak from the oil-filled cable 202. Acts as a barrier. According to an embodiment aspect, the glass fiber tube 210 has a cylindrical shape.

  According to one embodiment, the oil-filled cable 202 is impregnated by the paper roll 260 and wound by the paper stress cone 262 at the top of the paper roll 260. Paper stress cone 262 provides additional insulation to oil-filled cable 202.

  The HV electrode 212 is made of a semiconductor material and surrounds the modified joint core. The first end of the glass fiber tube 252 is also wound by the HV electrode 212. The HV electrode 212 controls the electric field within the change joint 200 so that the change joint 200 functions properly at all voltage loads and so that the change joint 200 can withstand a longer service life.

  The first deflector 214 is made of a semiconductor material and is located at a first end 226 of a joint body made in advance. The first deflector 215 has a tapered head section that wraps snugly around the glass fiber tube 210 and opens outward toward the center of the modified joint 200 to ensure a uniform distribution of the electric field.

  The second deflector 215 is made of a semiconductor material and is located at the second end 228 of the joint body made in advance. The second deflector 215 also has a tapered head section that tightly wraps around the end 222 of the solid insulated cable and opens outward toward the center of the modified joint 200 to ensure a uniform distribution of the electric field. ing.

  The joint body 216 made in advance is made of an elastic material having sufficient tension, and is tapered at both ends. A pre-made joint body 216 surrounds the first deflector 214 at the tapered first end 226 and the second deflector 215 at the tapered second end 228, respectively. The HV electrode 212 is entirely embedded and is enclosed within a pre-made intermediate section of the joint body 216.

  According to an embodiment aspect, the pre-made joint body 216 is made of silicone rubber. In other embodiments, the pre-made joint body 216 is made of ethylene-propylene rubber (EPR).

  The copper housing 218 surrounds the entire change joint and provides mechanical protection to the change joint 200 to form the outermost layer of the change joint 200. In one embodiment, the inner surface of the copper housing 218 is entirely covered by a cable wrap insulator 266.

  In one embodiment, the change joint 200 includes a cable packing retainer 264 that connects to the first end 250 of the copper housing and surrounds the tail section 220B at the end of the oil-filled cable. The cable packing retainer 264 seals the end of the oil-filled cable 220 and prevents water vapor from entering the end of the oil-filled cable 220. In another embodiment, the cable packing retainer 264 includes two cylindrical connecting tubes 244A-244B disposed on both sides of the cable packing retainer 264.

  According to an embodiment aspect, the modified joint includes a cable packing retainer that connects to the second end of the copper housing and surrounds the tail section of the end of the solid insulated cable. The cable packing retainer seals the end of the solid insulated cable and prevents water vapor from entering the end of the solid insulated cable. In one embodiment, the cable packing press includes two connecting pipes disposed on both sides of the cable packing press.

  In one embodiment, the first lead shroud 236 is at the first end 238 of the modified joint so that the first lead shroud 236 sufficiently surrounds the cable packing retainer 264 and the oil-filled cable end 220. The taper end of the cable packing retainer 264 is fixed by the tail section 220B at the end. In this way, the change joint 200 securely seals the oil-filled cable end 220 at the change joint first end 238.

  In one embodiment, to secure the copper housing 218 to the glass fiber tube 210, a T-shaped intermediate flange 246 and a bottom flange 248 are disposed at the first end 250 of the copper housing and relative to the second end 254 of the glass fiber tube. Touch. According to an embodiment aspect, the intermediate flange 246 is made of H62 copper and the bottom flange 248 is made of copper.

  In one embodiment, the second lead shroud 240 is at the end of the solid insulated cable at the second end 242 of the modified joint so that the second lead shroud 240 sufficiently surrounds the copper housing 218 and the end 222 of the solid insulated cable. Secure the second end 268 of the copper housing with the tail section 222B of the section. In this way, the modified joint 200 securely seals the end 222 of the solid insulated cable at the second end 242 of the modified joint.

  In one embodiment, the copper blade 256 secures the second end 268 of the copper housing and the end of the solid insulated cable so that the modified joint 200 securely seals the end of the solid insulated cable 222 at the second end 242 of the modified joint. Of the tail section 222B at the second end 242 of the change joint. Copper blade 256 prevents water vapor from entering solid insulated cable 204.

  In one embodiment, the insulation ring 258 is attached to the change joint 200 at the second tapered end 228 of the pre-made change joint to provide separation of the cover connecting the oil-filled cable 202 and the solid insulation cable 204. According to an embodiment aspect, the insulating ring 258 is made of an epoxy material.

  In one embodiment, the layer of copper blades and taping 270 are attached around a pre-made intermediate section of joint body 216.

  FIG. 3 shows a pre-made joint body 300 for a modified joint according to one embodiment. For the sake of clarity, the oil-filled cable and the solid insulated cable are not described in this embodiment.

  The pre-made joint body 300 includes a first tapered end 302, a second tapered end 304, and a cylindrical intermediate body 306 sandwiched between the first tapered end 302 and the second tapered end 304.

  The first deflector 308 made of a semiconductor material is located at the first tapered end 302. In one embodiment, the first deflector 308 has a tapered head section 310 that tightly surrounds the glass fiber tube 312 and a tail section 314 that branches out from the head section 310. With this particular arrangement, the first deflector 308 ensures a homogeneous distribution of the electric field at the first end 302 of the pre-made joint body. According to an embodiment aspect, the 310 head section is around the first end 324 of the glass fiber tube.

  In one embodiment, the glass fiber tube 312 has a cylindrical shape.

  A high voltage (HV) electrode 316 is embedded in the intermediate body 306 and surrounds the end 312 of the glass fiber tube. According to an embodiment aspect, the HV electrode 316 surrounds the second end 326 of the glass fiber tube.

  The second deflector 318 is made of a semiconductor material and is located at the second tapered end 304. In one embodiment, the second deflector 318 has a data head section 320 and a tail section 322 that branches out from the head section 310.

  FIG. 4 shows a modified joint glass fiber tube 400 according to one embodiment. For the sake of clarity, the oil-filled cable is not described in this embodiment.

  The glass fiber tube 400 is cylindrical in shape and includes a first end 402 that connects to a connector 404 and a second end 406 that connects to a T-shaped flange 408. Within the modified joint, the T-shaped flange 408 and the connector 404 are secured to the glass fiber tube 400. According to an embodiment aspect, the glass fiber tube is a hollow insulator.

  In one embodiment, the glass fiber tube 400 is inserted at the second end 406 into the end of the oil-filled cable (not shown).

  As used herein, a “change joint” is a cable joint that connects different types of cables or cables made of different materials. Examples of cables include, but are not limited to, oil-filled cables, cables with fluid or gas insulation materials, solid insulation cables and cross-linked polyethylene (XPLE) cables.

  As used herein, the term “oil” includes all types of fluids or viscous materials used in cable construction.

  As used herein, the term “tube” is not limited to objects having a circular cross section, but includes an elongated structure with cavities of any cross section.

  In order to control the electric field in the modified joint, the edges and / or surfaces of the deflector, insulating ring, pre-made joint body, and high voltage (HV) electrode are preferably round.

Claims (17)

It is a change joint that connects the oil-filled cable and the solid insulation cable,
The change joint includes a connector for fixing an end of the oil-filled cable and an end of the solid insulated cable to form a change joint core;
A glass fiber tube that is capped by the connector at a first end, inserted into the end of the oil-filled cable at a second end, and surrounds the end of the oil-filled cable inside the change joint;
A pre-made joint body surrounding the first deflector at the tapered first end, surrounding the second deflector at the tapered second end, and surrounding the high voltage (HV) electrode at the middle section;
A copper housing surrounding the pre-made joint body to form an outermost layer of the modified joint;
Change joint including. The modified joint according to claim 1, wherein the pre-made joint body is made of an elastic material. The modified joint of claim 1, wherein the first deflector includes a tapered head section surrounding the glass fiber tube at the first end of the pre-made joint body. The modified joint of claim 1, wherein the second deflector includes a tapered head section surrounding the end of the solid insulated cable at the second end of the pre-made joint body. The modified joint according to claim 1, wherein the HV electrode surrounds the modified joint core. The modified joint according to claim 1, wherein the HV electrode surrounds the first end of the glass fiber tube. The modified joint according to claim 1, wherein the glass fiber tube is fixed to the pre-made joint body with an epoxy resin at the second end of the glass fiber tube. A T-shaped intermediate flange disposed at a first end of the copper housing and in contact with the second end of the glass fiber tube;
A bottom flange disposed at a first end of the copper housing and in contact with the second end of the glass fiber tube;
The modified joint according to claim 1, wherein the T-shaped intermediate flange and the bottom flange are fixed to the glass fiber tube by the copper housing. The modified joint according to claim 1, wherein the glass fiber tube is hollow. A system for connecting an oil-filled cable and a solid insulated cable, the system comprising:
A solid metal connector for fixing the end of the oil-filled cable and the end of the solid insulated cable to form a core;
A cavity insulator connected to the solid metal connector at a first end, inserted into the end of the oil-filled cable at a second end, and concentrically surrounding the end of the oil-filled cable within the system;
An electric field controller that concentrically surrounds the cavity insulator and the solid metal connector and controls an electric field within the system;
A silicon rubber joint body concentrically surrounding the electric field controller;
A copper sleeve concentrically surrounding the silicone rubber joint body. The system of claim 10, wherein the electric field controller is concentrically enclosed within the silicone rubber joint body and concentrically surrounds the cavity insulator at a first end of the silicone rubber joint body. The electric field controller includes a second deflector that is concentrically enclosed within the silicone rubber joint body and concentrically surrounds the end portion of the solid insulated cable at a second end of the silicone rubber joint body. 10. The system according to 10. The system of claim 10, wherein the electric field controller includes a high voltage (HV) electrode concentrically surrounding the core. The system of claim 10, wherein the electric field controller concentrically surrounds the first end of the cavity insulator. The system of claim 10, wherein the cavity insulator is made of glass fiber. The system of claim 10, wherein the cavity insulator is secured to the silicon rubber joint body with an epoxy resin at the second end of the cavity insulator. A T-shaped intermediate flange disposed at a first end of the copper sleeve and in contact with the second end of the cavity insulator;
A bottom flange disposed at the first end of the copper sleeve and in contact with the second end of the cavity insulator;
With
The system of claim 10, wherein the T-shaped intermediate flange and the bottom flange are secured to the cavity insulator by the copper sleeve.

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