Power cable connection components, power cable connection structure, and power cable connection method
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- SUMITOMO ELECTRIC INDUSTRIES LTD
- Filing Date
- 2022-09-06
- Publication Date
- 2026-05-11
Smart Images
Figure 0007856530000001 
Figure 0007856530000002 
Figure 0007856530000003
Abstract
Description
Technical Field
[0001] The present disclosure relates to components for connecting power cables, a connection structure of power cables, and a method for connecting power cables.
Background Art
[0002] Patent Documents 1 and 2 disclose a solid-insulated busbar for connecting between power equipment. This solid-insulated busbar includes a conductor, a terminal connected to an end of the conductor, an insulating layer covering the outer periphery of the conductor, and a connection opening formed at an end of the insulating layer. The insertion region of a bushing provided in the power equipment is fitted into the connection opening. The connection opening is a recess formed by the insulating layer. The terminal is exposed within the connection opening. By inserting the bushing into the connection opening, the terminal and a conductor lead-out bar passing through the bushing are connected.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Patent Document 2
Summary of the Invention
Problems to be Solved by the Invention
[0004] For example, in a power facility where a gas-insulated switchgear (GIS) and a transformer are connected by a solid-insulated busbar, if either the GIS or the transformer fails, it is desirable to disconnect the solid-insulated busbar and connect the remaining healthy GIS or transformer to a replacement transformer or GIS using a power cable. In this way, by bypassing to a replacement power device with a power cable, it is possible to continue operation. In this case, since a power cable is connected to the power device instead of the solid-insulated busbar, a power cable connection component is required to connect the power cable to the bushing of the power device.
[0005] One of the objectives of this disclosure is to provide a power cable connection component that allows for easy connection of power cables to power equipment. Another objective of this disclosure is to provide a power cable connection structure comprising the above-mentioned power cable connection component. Yet another objective of this disclosure is to provide a method for connecting power cables using the above-mentioned power cable connection component. [Means for solving the problem]
[0006] The power cable connection component of this disclosure is a power cable connection component for connecting a power cable to a bushing provided on a power device, comprising a cylindrical connection member, a terminal portion provided at the end of the power cable, and a connection terminal, wherein the connection member has a cylindrical portion made of an insulating material and a first connection port and a second connection port opening at both ends of the cylindrical portion, respectively, the terminal portion has a first insertion region that fits into the first connection port, the first insertion region has an internal electrode connected to the cable conductor of the power cable and an insulating portion covering the internal electrode, the bushing has a second insertion region that fits into the second connection port, the second insertion region has a lead conductor and an insulating bushing covering the lead conductor, and the connection terminal connects the internal electrode and the lead conductor with the first insertion region fitted into the first connection port and the second insertion region fitted into the second connection port. [Effects of the Invention]
[0007] The power cable connection component of this disclosure allows for easy connection of power cables to power equipment. [Brief explanation of the drawing]
[0008] [Figure 1] Figure 1 is a schematic diagram showing the configuration of a power cable connection structure according to an embodiment. [Figure 2] Figure 2 is a schematic cross-sectional view showing an example of a connecting member provided in a power cable connection component according to the embodiment. [Figure 3] Figure 3 is a schematic partial cross-sectional view showing an example of a terminal portion provided in a power cable connection component according to an embodiment. [Figure 4] Figure 4 is a schematic diagram showing an example of a connection terminal provided in a power cable connection component according to the embodiment. [Figure 5] Figure 5 is a schematic diagram showing another example of a connection terminal provided in a power cable connection component according to the embodiment. [Figure 6] Figure 6 is a schematic diagram showing an example of the use of a power cable connection component according to the embodiment. [Figure 7] Figure 7 is a schematic diagram showing another example of the use of the power cable connection component according to the embodiment. [Modes for carrying out the invention]
[0009] [Description of Embodiments in this Disclosure] First, the embodiments of this disclosure will be listed and described.
[0010] (1) A power cable connection component according to an embodiment of the present disclosure is a power cable connection component for connecting a power cable to a bushing provided on a power device, comprising a cylindrical connection member, a terminal portion provided at the end of the power cable, and a connection terminal, wherein the connection member has a cylindrical portion made of an insulating material and a first connection port and a second connection port opening at both ends of the cylindrical portion, the terminal portion has a first insertion region that fits into the first connection port, the first insertion region has an internal electrode connected to the cable conductor of the power cable and an insulating portion covering the internal electrode, the bushing has a second insertion region that fits into the second connection port, the second insertion region has a lead conductor and an insulating bushing covering the lead conductor, and the connection terminal connects the internal electrode and the lead conductor with the first insertion region fitted into the first connection port and the second insertion region fitted into the second connection port.
[0011] The power cable connection component of this disclosure allows for easy connection of a power cable to power equipment. According to the power cable connection component of this disclosure, the first insertion area of the terminal portion and the second insertion area of the bushing are fitted into the first and second connection ports of the connection member, respectively. As a result, the first and second insertion areas are held facing each other in the axial direction of the connection member. The axial direction of the connection member is from the first connection port to the second connection port. With the internal electrode of the first insertion area and the lead conductor of the second insertion area aligned with each other in the axial direction, the connection terminal connects the internal electrode and the lead conductor.
[0012] (2) In the power cable connection component described in (1) above, the cylindrical portion may be made of silicone rubber.
[0013] The configuration of (2) above can improve the breakdown characteristics at the contact interfaces between each of the first insertion region and the second insertion region and the cylindrical portion. The cylindrical portion made of silicone rubber has good adhesion to the above regions and it is easy to ensure a stable surface pressure at the contact interfaces with the above regions. Therefore, even if the surface pressure at the contact interface is low, each of the above regions easily adheres to the cylindrical portion, and it is easy to maintain good breakdown characteristics at the contact interface.
[0014] (3) In the component for connecting a power cable of (1) or (2) above, the shape of the terminal portion may be L-shaped.
[0015] The configuration of (3) above can change the direction of the power cable extending from the terminal portion with respect to the bushing so as to be orthogonal.
[0016] (4) In the component for connecting a power cable of any one of (1) to (3) above, each of the first connection port and the second connection port may have a tapered surface whose inner diameter becomes smaller toward the middle portion of the cylindrical portion.
[0017] The configuration of (4) above makes it easy to fit the first insertion region and the second insertion region into the first connection port and the second connection port respectively. Furthermore, since the first connection port and the second connection port have tapered surfaces, it is easy to make the surface pressure at the contact interfaces between each of the first insertion region and the second insertion region and the cylindrical portion appropriate and uniform.
[0018] (5) In the component for connecting a power cable of (4) above, each of the first insertion region and the second insertion region may have a tapered surface whose outer diameter becomes smaller toward the respective tips.
[0019] The configuration of (5) above makes it easy to adhere each of the first insertion region and the second insertion region to the cylindrical portion. Since each of the above regions has a tapered surface according to the shape of each of the first connection port and the second connection port, it is easy to make the surface pressure at the contact interfaces between each of the above regions and the cylindrical portion appropriate and uniform.
[0020] (6) The power cable connection structure according to the embodiment of the present disclosure comprises a bushing provided on a power device, a power cable connected to the bushing, and a power cable connection component described in any one of (1) to (5) above.
[0021] The power cable connection structure of this disclosure, by including the power cable connection components of this disclosure, allows for easy connection of power cables to power equipment.
[0022] (7) A method for connecting a power cable according to an embodiment of the present disclosure is a method for connecting a power cable to a bushing provided on a power device, comprising the steps of: preparing a power cable connection component according to any one of (1) to (5) above; preparing a power cable with the terminal portion attached to the end of the power cable; attaching the connection terminal to the internal electrode of the first insertion region in the terminal portion or to the lead conductor of the second insertion region in the bushing; fitting the first insertion region into the first connection port of the connecting member; and fitting the second insertion region into the second connection port of the connecting member.
[0023] The power cable connection method disclosed herein allows for easy connection of power cables to power equipment by using the power cable connection components disclosed herein. The terminals attached to the ends of the power cables may be done on-site or in advance at the factory. If power cables with pre-attached terminals are provided, on-site terminal attachment work can be eliminated. Since on-site terminal attachment work is not required, the effort required for on-site work can be reduced.
[0024] [Details of the embodiments of this disclosure] Specific examples of power cable connection components, power cable connection structures, and power cable connection methods according to the embodiments of this disclosure will be described below with reference to the drawings. The same reference numerals in the drawings indicate the same or corresponding parts. Hereinafter, "power cable connection components" may be referred to as "connection components." However, the present invention is not limited to these examples, and is intended to include all modifications within the meaning and scope of the claims as shown, and equivalents thereof.
[0025] <Power cable connection parts> Referring to Figures 1 to 5, the connecting component 1 according to the embodiment will be described. Figure 1 shows the state in which the power cable 100 is connected to the power equipment 200 by the connecting component 1, that is, the power cable connection structure 10 according to the embodiment. The connecting component 1 is a group of components for connecting the power cable 100 to the bushing 210 provided on the power equipment 200. As shown in Figures 1 to 4, the connecting component 1 comprises a connecting member 2, a terminal portion 3, and a connecting terminal 4. The following will primarily refer to Figure 1 and first describe the power cable 100 and power equipment 200. Then, the connecting member 2, terminal 3, and connection terminal 4 that constitute the connecting component 1 will be described in detail.
[0026] <Power Cable> The power cable 100 has a cable conductor 101. The power cable 100 shown in Figure 1 has, in order from the center, a cable conductor 101, an internal semiconducting layer (not shown), an insulating layer 102, an external semiconducting layer 103, a shielding layer 104, and a sheath 105. The power cable 100 can be any known power cable. For example, the power cable 100 is a cross-linked polyethylene insulated sheathed cable (CV cable). The power cable 100 in this embodiment is a high-voltage cable of 66kV or higher. The conductor size of the power cable 100, i.e., the nominal cross-sectional area of the cable conductor 101, is, for example, 80 mm². 2 600mm or more 2 The following applies:
[0027] The end of the power cable 100 is stripped in sections, exposing the cable conductor 101, insulating layer 102, outer semiconducting layer 103, and shielding layer 104 in that order from the tip. A terminal fitting 110 is attached to the tip of the exposed cable conductor 101. A stress cone 120 is attached to the outer periphery of the exposed insulating layer 102. The stress cone 120 is in contact not only with the outer surface of the insulating layer 102 but also with a portion of the outer surface of the exposed outer semiconducting layer 103. The stress cone 120 mitigates the electric field concentration that occurs at the end of the power cable 100.
[0028] <Power equipment> The power equipment 200 is equipment installed in power facilities such as substations or power receiving facilities. The power equipment 200 is, for example, a switchgear or a transformer. The power equipment 200 shown in Figure 1 is a gas-insulated switchgear (GIS) 200G. The power equipment 200 is housed in a casing 201.
[0029] (Bushing) The power equipment 200 includes a bushing 210 to which the power cable 100 is connected. The bushing 210 is provided on the power equipment 200 so as to penetrate the wall surface of the housing 201. In this embodiment, the bushing 210 penetrates the side surface of the housing 201. The bushing 210 shown in Figures 1 and 4 is a GIS bushing 210G provided on the GIS200G. As shown in Figures 1 and 4, the bushing 210 has a second insertion region 220. The second insertion region 220 is located on the outside of the housing 201 of the bushing 210. The second insertion region 220 is fitted into the second connection port 22 of the connecting member 2 shown in Figure 2. The connecting member 2 will be described later. The second insertion region 220 includes a lead conductor 211 and an insulating bushing 212 that covers the lead conductor 211.
[0030] <Lead conductor> The lead conductor 211 is a rod-shaped body. The lead conductor 211 is made of a conductive material selected from, for example, copper and aluminum. In this embodiment, the material of the lead conductor 211 is aluminum. The shape of the lead conductor 211 is a round rod. The tip of the lead conductor 211 is locally thickened. A portion of the lead conductor 211 extends into the inner region located inside the housing 201 in the bushing 210. The tip of the lead conductor 211 is located outside the housing 201. The end of the lead conductor 211, away from the tip, is located inside the housing 201. The lead conductor 211 is connected to the power equipment 200 within the housing 201. The tip of the lead conductor 211 is led out to the outside of the housing 201 through the insulating bushing 212.
[0031] <Insulating bushing> The insulating bushing 212 is a cylindrical body through which the lead conductor 211 passes. A portion of the insulating bushing 212, like the lead conductor 211, extends to the inner region of the bushing 210. The portion of the insulating bushing 212 that covers the tip of the lead conductor 211 is located outside the housing 201. The portion of the insulating bushing 212 that covers the end of the lead conductor 211 away from the tip is located inside the housing 201. The insulating bushing 212 electrically insulates the lead conductor 211 from the housing 201. The insulating bushing 212 is made of an insulating material selected from, for example, resin and porcelain. In this embodiment, the insulating bushing 212 is formed by molding resin onto the outer circumferential surface of the lead conductor 211. The material of the insulating bushing 212 is epoxy resin.
[0032] The insulating bushing 212 is attached to the housing 201 so as to penetrate the wall surface of the housing 201. In other words, a part of the insulating bushing 212 is located inside the housing 201. The insulating bushing 212 in this embodiment has a flange portion 212f. The flange portion 212f is provided between both ends of the insulating bushing 212. The flange portion 212f protrudes radially from the outer circumferential surface of the insulating bushing 212. This radial direction is outward from the central axis of the insulating bushing 212. In this embodiment, a mounting portion 202 is provided on the wall surface of the housing 201. The insulating bushing 212 is supported by the housing 201 by attaching the flange portion 212f to this mounting portion 202. The flange portion 212f is fastened to the mounting portion 202 by bolts.
[0033] In this embodiment, the second insertion region 220 has a tapered surface 220t, as shown in Figure 4, with an outer diameter that decreases towards the tip of the second insertion region 220. The outer circumferential surface of the second insertion region 220 is formed in the shape of a frustocone. The tip of the second insertion region 220 is the end furthest from the power equipment 200. The taper angle of the tapered surface 220t is, for example, 4° or more and 7° or less. The taper angle of the tapered surface 220t refers to the angle between the central axis of the second insertion region 220 and the tapered surface 220t. The inner region of the bushing 210 also has a tapered shape with an outer diameter that decreases towards the inside of the housing 201.
[0034] (Connecting component) The connecting member 2 is one of the components that make up the connecting part 1. Here, the connecting member 2 will be described mainly with reference to Figure 2, and with reference to Figures 1 and 3 as appropriate. The connecting member 2 is a cylindrical component. The connecting member 2 has a cylindrical portion 20 and a first connecting port 21 and a second connecting port 22. Figure 2 is a longitudinal cross-sectional view of the connecting member 2 cut along the central axis of the cylindrical portion 20. In this embodiment, the shape of the connecting member 2 is cylindrical.
[0035] <Cylindrical part> The cylindrical portion 20 is made of an insulating material. The insulating material is, for example, resin or rubber. The rubber constituting the cylindrical portion 20 is, for example, silicone rubber or ethylene propylene rubber (EP rubber). In this embodiment, the cylindrical portion 20 is made of rubber. Specifically, the cylindrical portion 20 is made of silicone rubber. The shape of the cylindrical portion 20 is cylindrical.
[0036] The connecting member 2 of this embodiment has an internal semiconducting layer 20i on the inner circumferential surface of the cylindrical portion 20, and an external semiconducting layer 20o on the outer circumferential surface of the cylindrical portion 20. The internal semiconducting layer 20i and the external semiconducting layer 20o mitigate electric field concentration in the cylindrical portion 20. The internal semiconducting layer 20i is provided on the inner circumferential surface of the cylindrical portion 20, between both ends of the cylindrical portion 20. As shown in Figure 1, the internal semiconducting layer 20i is provided at a position corresponding to the outer circumference of the connecting terminal 4, with the first insertion area 31 and the second insertion area 220 fitted into the first connection port 21 and the second connection port 22, respectively. The external semiconducting layer 20o is provided so as to cover the entire length of the outer circumferential surface of the cylindrical portion 20. The internal semiconducting layer 20i and the external semiconducting layer 20o of this embodiment are made of semiconducting rubber. Semiconducting rubber is rubber to which a conductive filler has been added in order to impart semiconductivity. Specifically, the inner semiconducting layer 20i and the outer semiconducting layer 20o are made of silicone rubber containing a conductive filler.
[0037] <First connection port, second connection port> The first connection port 21 and the second connection port 22 open at both ends of the cylindrical portion 20, respectively. As shown in Figure 1, the first insertion area 31 of the terminal portion 3 shown in Figure 3 is fitted into the first connection port 21. The terminal portion 3 will be described later. The second insertion area 220 of the bushing 210 described above is fitted into the second connection port 22. When the first insertion area 31 and the second insertion area 220 are fitted into the first connection port 21 and the second connection port 22, respectively, the respective areas of the first insertion area 31 and the second insertion area 220 are in close contact with the cylindrical portion 20. In this embodiment, the first connection port 21 and the second connection port 22 are formed symmetrically with respect to a center line that divides the cylindrical portion 20 in the axial direction. This axial direction is from the first connection port 21 to the second connection port 22. The first connection port 21 and the second connection port 22 are substantially the same shape and size. Note that "identical" here does not mean completely identical, but includes manufacturing tolerances. The statement that the first connection port 21 and the second connection port 22 are the same size means that the length and inner diameter of the first connection port 21 and the second connection port 22 are the same. The length of the first connection port 21 and the second connection port 22 is the length along the axial direction of the cylindrical portion 20. That is, the length of the first connection port 21 is the distance from the end face of the cylindrical portion 20 where the first connection port 21 opens to the center line. The length of the second connection port 22 is the distance from the end face of the cylindrical portion 20 where the second connection port 22 opens to the center line.
[0038] In this embodiment, the first connection port 21 and the second connection port 22 each have tapered surfaces 21t and 22t, respectively, whose inner diameter decreases towards the middle of the cylindrical portion 20. The inner circumferential surfaces of the first connection port 21 and the second connection port 22 are formed in a frustoconical shape. The taper angles of the tapered surface 21t of the first connection port 21 and the tapered surface 22t of the second connection port 22 are substantially the same. The taper angle of each tapered surface 21t and 22t refers to the angle made between the central axis of the cylindrical portion 20 and each tapered surface 21t and 22t. The taper angles of the tapered surfaces 21t and 22t are, for example, 4° to 7°.
[0039] The inner diameters of the first connection port 21 and the second connection port 22 are smaller than the outer diameters of the first insertion region 31 and the second insertion region 220, respectively, before the first insertion region 31 and the second insertion region 220 are fitted into the first connection port 21 and the second connection port 22, respectively. In this embodiment, since the cylindrical portion 20 is made of rubber, the first insertion region 31 and the second insertion region 220 can be fitted into the first connection port 21 and the second connection port 22 by the elastic deformation of the cylindrical portion 20. As shown in Figure 1, after the first insertion region 31 and the second insertion region 220 are fitted into the first connection port 21 and the second connection port 22, respectively, the inner diameters of the first connection port 21 and the second connection port 22 are expanded.
[0040] Furthermore, before the first insertion region 31 and the second insertion region 220 are fitted into the first connection port 21 and the second connection port 22, respectively, the taper angle of the tapered surface 21t is approximately the same as the taper angle of the tapered surface 31t of the first insertion region 31 shown in Figure 3. In this embodiment, the taper angle of the tapered surface 21t is slightly smaller than the taper angle of the tapered surface 31t. The difference between the taper angle of the tapered surface 31t and the taper angle of the tapered surface 21t may be, for example, 0.5° or more and 2.5° or less, and further 1° or more and 2° or less. Also, the taper angle of the tapered surface 22t is approximately the same as the taper angle of the tapered surface 220t of the second insertion region 220 shown in Figure 4. In this embodiment, the taper angle of the tapered surface 22t is slightly smaller than the taper angle of the tapered surface 220t. The difference between the taper angle of tapered surface 220t and the taper angle of tapered surface 22t may be, for example, 0.5° or more and 2.5° or less, and further 1° or more and 2° or less. In this embodiment, the taper angles of tapered surface 21t and tapered surface 22t are approximately 4°, while the taper angles of tapered surface 31t and tapered surface 220t are approximately 5°.
[0041] In addition, the connecting member 2 of this embodiment has flange plates 26f and 27f provided at both ends of the cylindrical portion 20. The flange plate 26f is positioned on the end face of the cylindrical portion 20 through which the first connection port 21 opens. The flange plate 27f is positioned on the end face of the cylindrical portion 20 through which the second connection port 22 opens. Each flange plate 26f and 27f is an annular body. The first connection port 21 and the second connection port 22 are not blocked by the flange plates 26f and 27f. The flange plates 26f and 27f are made of a metallic material selected from, for example, brass, aluminum alloy, and stainless steel.
[0042] As shown in Figure 1, the flange plate 26f is fixed to the flange portion 35f with the first insertion area 31 of the terminal portion 3 fitted into the first connection port 21. The flange plate 26f and the flange portion 35f are fastened together with bolts. The flange portion 35f will be described later. The flange plate 27f is fixed to the flange portion 212f described above with the second insertion area 220 of the bushing 210 fitted into the second connection port 22. The flange plate 27f and the flange portion 212f are fastened together with bolts.
[0043] The outer semiconducting layer 20o may be electrically grounded. For example, the outer semiconducting layer 20o may be electrically connected to the shielding layer 104 exposed at the end of the power cable 100. Normally, the shielding layer 104 of the power cable 100 is grounded. Therefore, the outer semiconducting layer 20o can be grounded by connecting it to the shielding layer 104 exposed by stripping the end of the power cable 100. The outer semiconducting layer 20o and the shielding layer 104 may be connected by, for example, a grounding wire (not shown). In this embodiment, the outer semiconducting layer 20o is in contact with the flange plates 26f and 27f. Therefore, either of the flange plates 26f and 27f may be connected to the shielding layer 104 by a grounding wire. In this case, the outer semiconducting layer 20o will be grounded by the electrical connection between the flange plate and the shielding layer 104.
[0044] (Terminal section) The terminal portion 3 is one of the components that make up the connecting component 1. Here, the terminal portion 3 will be explained mainly with reference to Figure 3, and with reference to Figure 1 and other figures as appropriate. The terminal portion 3 is provided at the end of the power cable 100. The terminal portion 3 has a first insertion area 31. The first insertion area 31 is fitted into the first connection port 21 of the connecting member 2 shown in Figure 2. The first insertion area 31 has an internal electrode 32 and an insulating portion 35.
[0045] <Internal electrode> The internal electrode 32 is connected to the cable conductor 101 of the power cable 100. The internal electrode 32 is made of a conductive material selected from, for example, copper and aluminum. In this embodiment, the material of the internal electrode 32 is aluminum. The shape of the internal electrode 32 is a round bar. The tip of the internal electrode 32 is locally thickened. A connection terminal 4, shown in Figure 4, is connected to the tip of the internal electrode 32. The connection terminal 4 will be described later. As shown in Figure 1, with the first insertion area 31 and the second insertion area 220 fitted into the first connection port 21 and the second connection port 22 respectively, the tips of the internal electrode 32 and the lead conductor 211 face each other at the midpoint of the cylindrical portion 20. The internal electrode 32 and the lead conductor 211 are connected via the connection terminal 4. In this embodiment, as shown in Figure 3, a recess 32o is formed on the end face of the tip of the internal electrode 32. The first protrusion 41 of the connection terminal 4 is fitted into this recess 32o, thereby connecting the internal electrode 32 and the connection terminal 4.
[0046] The internal electrode 32 includes a conductor connection portion 33. The conductor connection portion 33 is located at the tip of the cable conductor 101 that is exposed from the end of the power cable 100. The cable conductor 101 is connected to the conductor connection portion 33. In this embodiment, as shown in Figure 3, an insertion hole 33o is formed in the conductor connection portion 33. The cable conductor 101 is connected to the conductor connection portion 33 by fitting a terminal fitting 110 provided at the tip of the cable conductor 101 into this insertion hole 33o. A multi-faceted contact, such as a multi-ram band (product name), is attached to the outer circumferential surface of the terminal fitting 110 (not shown). The conductor connection portion 33 in this embodiment is a short, round bar-shaped member. An insertion hole 33o is formed on the end face of the conductor connection portion 33 closest to the cable conductor 101. The end of the conductor connection portion 33 opposite to the end with the insertion hole 33o has a hemispherical shape. The internal electrode 32 is configured in an L-shape overall. The internal electrode 32 located in the first insertion region 31 extends outward from the central axis of the conductor connection portion 33.
[0047] <Insulation> The insulating portion 35 covers the internal electrode 32. The internal electrode 32 penetrates the center of the insulating portion 35. The insulating portion 35 is made of an insulating material selected from, for example, resin and rubber. In this embodiment, the material of the insulating portion 35 is epoxy resin. The insulating portion 35 includes a covering portion 36 that covers the end of the power cable 100. The covering portion 36 has a cable insertion hole 36o formed therein for inserting the end of the power cable 100. A stress cone 120 is placed inside the covering portion 36. The insulating portion 35 is configured in an L-shape overall. This is because the insulating portion 35 is provided to cover the outer circumference of the L-shaped internal electrode 32. In this embodiment, the insulating portion 35 is formed by molding resin onto the outer surface of the internal electrode 32.
[0048] The insulating portion 35 of this embodiment has a flange portion 35f. The flange portion 35f is fixed to the flange plate 26f of the connecting member 2 shown in Figure 2. The flange portion 35f is provided in a position facing the flange plate 26f with the first insertion area 31 fitted into the first connection port 21, as shown in Figure 1.
[0049] The first insertion region 31 in this embodiment has a tapered surface 31t whose outer diameter decreases towards the tip of the first insertion region 31. The outer circumferential surface of the first insertion region 31 is formed in the shape of a frustocone. The tip of the first insertion region 31 is the end furthest from the cable conductor 101. The taper angle of the tapered surface 31t is, for example, 4° or more and 7° or less. The taper angle of the tapered surface 31t refers to the angle between the central axis of the first insertion region 31 and the tapered surface 31t. In this embodiment, the first insertion region 31 is substantially the same shape and size as the second insertion region 220 of the bushing 210 shown in Figure 4. The first insertion region 31 and the second insertion region 220 being the same size means that the lengths and outer diameters of the first insertion region 31 and the second insertion region 220 are the same. Furthermore, the taper angles of the tapered surface 31t and the tapered surface 220t are also substantially the same.
[0050] In this embodiment, the shape of the terminal portion 3 is L-shaped. The L-shape of the terminal portion 3 means that the first insertion region 31 extends so as to intersect with the extension direction of the end of the power cable 100. The first insertion region 31 may also extend in a direction perpendicular to the extension direction of the end of the power cable 100, as shown in Figure 1. When the shape of the terminal portion 3 is L-shaped, the orientation of the power cable 100 extending from the terminal portion 3 to the bushing 210 can be changed to be perpendicular to it, as shown in Figure 1. Unlike this embodiment, the first insertion region 31 may be provided so as to extend in the extension direction of the end of the power cable 100. In this case, the shape of the terminal portion 3 is I-shaped.
[0051] (Connection terminals) The connection terminal 4 is one of the components that make up the connection component 1. Here, the connection terminal 4 will be explained mainly with reference to Figure 4, and with reference to Figure 1 and other figures as appropriate. The bushing 210 shown in Figure 4 is the GIS bushing 210G provided in the GIS 200G. The connection terminal 4 shown in Figure 4 is the GIS connection terminal 4G used in the GIS bushing 210G. As shown in Figure 1, the connection terminal 4 connects the internal electrode 32 and the lead conductor 211 with the first insertion area 31 fitted into the first connection port 21 and the second insertion area 220 fitted into the second connection port 22. The connection terminal 4 is made of a conductive material selected from, for example, copper and aluminum. In this embodiment, the material of the connection terminal 4 is copper.
[0052] In this embodiment, the connector 4 is attached to the lead conductor 211 in the second insertion region 220 of the bushing 210. The connector 4 is fixed to the end face of the tip of the lead conductor 211 by a bolt (not shown). The connector 4 in this embodiment also has a first protrusion 41. The first protrusion 41 is fitted into a recess 32o provided in the internal electrode 32. The first protrusion 41 is provided at the end of the connector 4 facing the internal electrode 32. Unlike this embodiment, the connector 4 can also be attached to the internal electrode 32 in the first insertion region 31 of the terminal portion 3 shown in Figure 3.
[0053] Figures 1 and 4 illustrate the case where connection terminal 4 is a GIS connection terminal 4G. Another example of connection terminal 4 will be explained with reference to Figure 5. The power equipment 200 shown in Figure 5 is a transformer 200T. The bushing 210 shown in Figure 5 is a transformer bushing 210T provided on the transformer 200T. To begin with, the configuration of the transformer bushing 210T in this embodiment will be explained. The configuration of the transformer bushing 210T is generally the same as the configuration of the bushing 210, i.e., the GIS bushing 210G, shown in Figures 1 and 4. In addition, in this embodiment, the second insertion region 220 of the transformer bushing 210T and the second insertion region 220 of the GIS bushing 210G are substantially the same shape and size. However, the transformer bushing 210T has a longer inner region located inside the housing 201 compared to the GIS bushing 210G. Furthermore, the trans bushing 210T has multiple folds formed on the outer circumference of the insulating bushing 212 in the inner region. In this embodiment, as shown in Figure 5, the trans bushing 210T has a recess 211o formed at the tip of the lead conductor 211 in the second insertion region 220.
[0054] The connector terminal 4 shown in Figure 5 is a transformer connector terminal 4T used in the transformer bushing 210T. Like the GIS connector terminal 4G shown in Figure 4, the transformer connector terminal 4T is fixed to the end face of the tip of the lead conductor 211 by a bolt (not shown). In this embodiment, the transformer connector terminal 4T has a second protrusion 42 in addition to the first protrusion 41 described above. The second protrusion 42 is fitted into a recess 211o provided in the lead conductor 211. With the second protrusion 42 fitted into this recess 211o, the connector terminal 4 is fixed to the lead conductor 211. The second protrusion 42 is provided at the end of the transformer connector terminal 4T that faces the lead conductor 211. As shown in Figure 5, when the lead conductor 211 has a recess 211o and the connector terminal 4 has a second protrusion 42, it is easy to adopt the configuration in which the connector terminal 4 described above is attached to the internal electrode 32. The second protrusion 42 is fitted into the recess 211o, making it possible to properly connect the lead conductor 211 and the connection terminal 4.
[0055] <Power cable connection structure> The power cable connection structure 10 according to the embodiment will be described with reference mainly to Figure 1. The connection structure 10 comprises a bushing 210 provided on the power equipment 200, a power cable 100 connected to the bushing 210, and a connecting component 1. The configurations of the power equipment 200, bushing 210, power cable 100, and connecting component 1 have been described in the embodiment of connecting component 1 described above, so a detailed description will be omitted here.
[0056] In the connection structure 10, the power cable 100 is connected to the bushing 210 of the power equipment 200 by the connecting component 1. The first insertion area 31 of the terminal portion 3 is fitted into the first connection port 21 of the connecting member 2, and the second insertion area 220 of the bushing 210 is fitted into the second connection port 22 of the connecting member 2. With the first insertion area 31 and the second insertion area 220 fitted into the first connection port 21 and the second connection port 22 respectively, the internal electrode 32 of the terminal portion 3 and the lead conductor 211 of the bushing 210 are connected via the connection terminal 4.
[0057] <How to connect power cables> The power cable connection method according to the embodiment will be described with reference to Figures 1 to 4 as appropriate. The power cable connection method according to the embodiment uses the connection component 1 described above. The power cable connection method comprises the following steps. Step a. Step of preparing connecting part 1. Step b. A step of preparing a power cable 100 with the terminal part 3 attached. Step c. The step of attaching the connection terminal 4 to the internal electrode 32 or lead conductor 211. Step d. The step of fitting the first insertion area 31 into the first connection port 21. Step e. The step of fitting the second insertion area 220 into the second connection port 22. The following describes each of the above steps. Note that the configurations of the power equipment 200, bushing 210, power cable 100, and connecting component 1 were described in the embodiment of connecting component 1 above, so a detailed explanation is omitted here.
[0058] (Step a) Step a is the step of preparing the connecting component 1. As shown in Figures 1 to 4, the connecting component 1 comprises a connecting member 2, a terminal portion 3, and a connecting terminal 4.
[0059] (Step b) Step b involves preparing a power cable 100 with terminals 3 attached to its ends, as shown in Figure 3. The attachment of terminals 3 to the ends of the power cable 100 may be done on-site or in advance at the factory. If a power cable 100 with terminals 3 already attached is prepared, the on-site attachment work of terminals 3 can be eliminated.
[0060] The terminal portion 3 is attached to the end of the power cable 100 as follows. The terminal portion 3 has an insulating portion 35 pre-formed on the internal electrode 32. First, the end of the power cable 100 is stripped in steps to expose the cable conductor 101. The end of the power cable 100 is inserted into the cable insertion hole 36o of the terminal portion 3, positioning the end of the power cable 100 within the covering portion 36, and the exposed cable conductor 101 is connected to the internal electrode 32 of the terminal portion 3. In this embodiment, after the cable conductor 101 is exposed, a terminal fitting 110 is attached to the tip of the exposed cable conductor 101. A multi-faceted contact is attached to the outer surface of the terminal fitting 110. Then, the terminal fitting 110 provided on the tip of the cable conductor 101 is fitted into the insertion hole 33o of the conductor connection portion 33.
[0061] (Step c) Step c is the step of attaching the connection terminal 4 to the internal electrode 32 or the lead conductor 211. Specifically, step c is the step of attaching the connection terminal 4 to the internal electrode 32 in the first insertion region 31 of the terminal portion 3, or to the lead conductor 211 in the second insertion region 220 of the bushing 210. In this embodiment, as shown in Figure 4, the connection terminal 4 is attached to the lead conductor 211. The connection terminal 4 is attached to the lead conductor 211 by, for example, fastening with a bolt. Unlike this embodiment, the connection terminal 4 may be attached to the internal electrode 32.
[0062] (Step d) Step d is the step of fitting the first insertion area 31 into the first connection port 21 of the connecting member 2 shown in Figure 2. When fitting the first insertion area 31 into the first connection port 21, it is best to push the first insertion area 31 into the first connection port 21. In this embodiment, after fitting the first insertion area 31 into the first connection port 21, the flange plate 26f of the connecting member 2 and the flange portion 35f of the insulating portion 35 are fastened together with bolts.
[0063] (Step e) Step e is the step of fitting the second insertion area 220 into the second connection port 22 of the connecting member 2 shown in Figure 2. When fitting the second insertion area 220 into the second connection port 22, it is best to push the second insertion area 220 into the second connection port 22. In this embodiment, after fitting the second insertion area 220 into the second connection port 22, the flange plate 27f of the connecting member 2 and the flange portion 212f of the insulating bushing 212 are fastened together with bolts.
[0064] The order of step b, which involves preparing the power cable 100 with the terminal section 3 attached, and step c, which involves attaching the connection terminal 4, may be reversed. The order of step d, which involves fitting the first insertion area 31 into the first connection port 21, and step e, which involves fitting the second insertion area 220 into the second connection port 22, may be reversed or performed simultaneously.
[0065] By fitting the first insertion area 31 and the second insertion area 220 into the first connection port 21 and the second connection port 22, respectively, as shown in Figure 1, the internal electrode 32 and the lead conductor 211 can be connected via the connection terminal 4.
[0066] The connecting component 1, the power cable connection structure 10, and the power cable connection method of this embodiment provide the following effects.
[0067] The power cable 100 can be easily connected to the power equipment 200. With the connecting component 1, the first insertion area 31 of the terminal portion 3 and the second insertion area 220 of the bushing 210 are fitted into the first connection port 21 and the second connection port 22 of the connecting member 2, respectively. As a result, the first insertion area 31 and the second insertion area 220 are held facing each other in the axial direction of the connecting member 2. With the internal electrode 32 of the first insertion area 31 and the lead conductor 211 of the second insertion area 220 aligned with each other in the axial direction, the internal electrode 32 and the lead conductor 211 can be connected via the connecting terminal 4.
[0068] This configuration improves the dielectric breakdown characteristics at the contact interface between the first insertion region 31 and the second insertion region 220 and the cylindrical portion 20. In this embodiment, the cylindrical portion 20 is made of rubber. Furthermore, the inner diameter of the first connection port 21 and the second connection port 22 is smaller than the outer diameter of the first insertion region 31 and the second insertion region 220 before they are fitted into the first and second connection ports 21 and 22, respectively. When the first and second insertion regions 31 and 220 are fitted into the first and second connection ports 22, the cylindrical portion 20 is elastically deformed. As a result, the cylindrical portion 20 is in close contact with the first and second insertion regions 31 and 220, and surface pressure is applied to the contact interface between these regions and the cylindrical portion 20. This surface pressure at the contact interface improves the dielectric breakdown characteristics. In particular, when the cylindrical portion 20 is made of silicone rubber, it exhibits good adhesion to each of the above-mentioned regions, making it easy to secure a stable surface pressure at the contact interface with each of the above-mentioned regions. Therefore, even if the surface pressure at the contact interface is low, it is easy to maintain good dielectric breakdown characteristics at the contact interface.
[0069] The first insertion area 31 and the second insertion area 220 are easily fitted into the first connection port 21 and the second connection port 22, respectively. In this embodiment, the first connection port 21 and the second connection port 22 each have tapered surfaces 21t and 22t, respectively, where the inner diameter decreases towards the middle of the cylindrical portion 20. Since the inner diameter of the first connection port 21 and the second connection port 22 is larger closer to the end face of the cylindrical portion 20, the first insertion area 31 and the second insertion area 220 are easily fitted into them, respectively. In addition, because the first connection port 21 and the second connection port 22 each have tapered surfaces 21t and 22t, it is easy to make the surface pressure at the contact interface between each region of the first insertion area 31 and the second insertion area 220 and the cylindrical portion 20 appropriate and uniform.
[0070] Furthermore, the first insertion region 31 and the second insertion region 220 each have tapered surfaces 31t and 220t, respectively, with their outer diameters decreasing towards their respective ends. This makes it easier to bring the first insertion region 31 and the second insertion region 220 into close contact with the cylindrical portion 20. In addition, it makes it easier to ensure that the surface pressure at the contact interface between each of the above regions and the cylindrical portion 20 is appropriate and uniform.
[0071] 《Application》 Specific examples of the uses of the connecting component 1 of the embodiment will be explained with reference to Figures 6 and 7.
[0072] (For bypassing power equipment failures) An example of using the connecting component is when one of two power devices fails, and the remaining healthy power device is connected to a power cable to bypass the power supply to the replacement power device via the power cable. Figure 6 shows an example where, in a system of GIS200G and transformer 200T, transformer 200T fails, and the healthy GIS200G is connected to a replacement transformer (not shown) by a power cable 100. In this case, as shown in Figure 6, the power cable 100 is connected to the GIS bushing 210G of the GIS200G by the connecting component 1. A terminal part 3 is attached to the end of the power cable 100 that is connected to the GIS bushing 210G. Although not shown here, the end of the power cable 100 furthest from the GIS bushing 210G is connected to the transformer bushing of the replacement transformer. This furthest end of the power cable 100 is also connected to the transformer bushing by the connecting component.
[0073] The terminal portion 3 of this embodiment is L-shaped. Therefore, the orientation of the power cable 100 extending from the terminal portion 3 can be changed to be perpendicular to the GIS bushing 210G. As shown in Figure 6, even if the GIS bushing 210G and the transformer bushing 210T are facing each other and in close proximity, it is easy to install the power cable 100 so that it does not interfere with the GIS 200G or the transformer 200T.
[0074] (For shipment testing of power equipment) Another use case for the connecting component is in the shipping test of power equipment, where a power cable is connected to the power equipment and the power equipment is connected to the test device with the power cable. The shipping test is a voltage withstand test, etc. Figure 7 shows an example of connecting a GIS200G and an air terminal 300 for voltage withstand testing with a power cable 100. As shown in Figure 7, the power cable 100 is connected to the GIS bushing 210G of the GIS200G using the connecting component 1. The voltage withstand test is performed by applying power from the air terminal 300. The air terminal 300 is installed on a frame 350. A known type of air terminal 300 can be used. [Explanation of Symbols]
[0075] 1. Connecting parts 10 Connection Structure 2 Connecting members 20 Cylindrical part 20i internal semiconducting layer 20° Outer semiconducting layer 21 First connection port, 22 Second connection port 21t, 22t tapered surface 26f, 27f flange plate 3 Terminal section 31 First insertion area, 31t tapered surface 32 internal electrode, 32o recess 33 Conductor connection part, 33o Insertion hole 35 Insulation part 36 Covering portion, 36o Cable insertion hole 35f flange section 4 Connection terminals 4G GIS connection terminal, 4T transformer connection terminal 41 First protrusion, 42 Second protrusion 100 Power Cables 101 Cable conductor, 102 Insulation layer 103 Outer semiconducting layer, 104 Shielding layer, 105 Sheath 110 Terminal fittings, 120 Stress cone 200 Power equipment 200G GIS, 200T transformer 201 cabinet 202 Mounting section 210 Bushing 210G GIS bushing, 210T trans bushing 211 Lead conductor, 212 Insulating bushing 211o recess 212f Flange section 220 Second insertion area, 220t tapered surface 300 airborne terminals, 350 mounting units
Claims
1. A power cable connector component for connecting a power cable to a bushing provided in power equipment, A cylindrical connecting member, The terminal portion provided at the end of the aforementioned power cable, Equipped with connection terminals, The aforementioned connecting member is A cylindrical part made of insulating material, The cylindrical portion has a first connection port and a second connection port that open at both ends, The cylindrical portion has a flange plate positioned on the end face through which the first connection port opens, The aforementioned terminal portion is It has a first insertion area that fits into the first connection port, The first insertion region has an internal electrode connected to the cable conductor of the power cable and an insulating portion covering the internal electrode. The insulating portion has a flange portion that is fastened to the flange plate by bolts when the first insertion region is fitted into the first connection port. The aforementioned bushing is It has a second insertion area that fits into the second connection port, The second insertion region comprises a lead conductor and an insulating bushing that covers the lead conductor. The aforementioned connection terminal connects the internal electrode and the lead conductor with the first insertion area fitted into the first connection port and the second insertion area fitted into the second connection port. Components for connecting power cables.
2. A power cable connector component for connecting a power cable to a bushing provided in power equipment, A cylindrical connecting member, The terminal portion provided at the end of the aforementioned power cable, Equipped with connection terminals, The aforementioned connecting member is A cylindrical part made of insulating material, The cylindrical portion has a first connection port and a second connection port opening at both ends, The aforementioned terminal section is It has a first insertion area that fits into the first connection port, The first insertion region has an internal electrode connected to the cable conductor of the power cable and an insulating portion covering the internal electrode. The aforementioned bushing is It has a second insertion area that fits into the second connection port, The second insertion region comprises a lead conductor and an insulating bushing that covers the lead conductor. The aforementioned connection terminal connects the internal electrode and the lead conductor with the first insertion area fitted into the first connection port and the second insertion area fitted into the second connection port. The cylindrical portion is thicker in the middle section where the connecting terminals are located than at both ends, and its outer diameter decreases from the middle section towards both ends. Components for connecting power cables.
3. The power cable connection component according to claim 1 or claim 2, wherein the cylindrical portion is made of silicone rubber.
4. The power cable connection component according to claim 1 or claim 2, wherein the shape of the terminal portion is L-shaped.
5. The power cable connection component according to claim 1 or claim 2, wherein each of the first connection port and the second connection port has a tapered surface whose inner diameter decreases toward the middle of the cylindrical portion.
6. The power cable connection component according to claim 5, wherein each of the first insertion region and the second insertion region has a tapered surface whose outer diameter decreases toward its respective tip.
7. Bushings installed in power equipment, A power cable connected to the bushing, A power cable connection component according to claim 1 or claim 2, Power cable connection structure.
8. A method for connecting a power cable to a bushing provided on power equipment, A step of preparing the power cable connection component according to claim 1 or claim 2, A step of preparing the power cable by attaching the terminal portion to the end of the power cable, A step of attaching the connection terminal to the internal electrode of the first insertion region in the terminal portion, or to the lead conductor of the second insertion region in the bushing, The process of fitting the first insertion area into the first connection port of the connecting member, The process includes fitting the second insertion area into the second connection port of the connecting member. How to connect power cables.