SE1000113A0

SE1000113A0 - A cable termination arrangement

Info

Publication number: SE1000113A0
Application number: SE1000113A
Authority: SE
Inventors: Bohlin Åke; Svahn Jörgen; Ming Li
Original assignee: Abb Research Ltd
Priority date: 2010-02-05
Filing date: 2010-02-05
Publication date: 2010-02-12
Also published as: SE1000113L

Description

10 The object of the invention is achieved by means of the cable terrnination arrangement according to the invention, characterised in that, in said part in which there is a spacing between the outer periphery of the cable and the inner periphery of the insulator, there is provided at least one support element that beats against the outer periphery of the cable and against the inner periphery of the insulator and holds the cable in a predetermined position in relation to the insulator. Thereby, misalignment of the cable, and consequently disturbances of the ﬁeld distribution around the cable, is avoided. Preferably, the hollow volume of the insulator is cylindrical, and the cable is held in a central position in said volume, such that the longitudinal central axes of the insulator and the cable are coaxial and identical. 10 The object of the invention is achieved by means of the cable terrnination arrangement according to the invention, characterized in that, in said part in which there is a spacing between the outer periphery of the cable and the inner periphery of the insulator, there is provided at least one support element that beats against the outer periphery of the cable and against the inner periphery of the insulator and holds the cable in a predetermined position in relation to the insulator. Thereby, misalignment of the cable, and consequently disturbances of the distribution eld distribution around the cable, is avoided. Preferably, the hollow volume of the insulator is cylindrical, and the cable is held in a central position in said volume, such that the longitudinal central axes of the insulator and the cable are coaxial and identical.

According to one embodiment, the support element presents at least two radial struts, each strut extending between the outer periphery of the cable and the inner periphery of the insulator.According to one embodiment, the support element presents at least two radial struts, each strut extending between the outer periphery of the cable and the inner periphery of the insulator.

According to one embodiment, said struts extend generally in a radial direction perpendicular to the longitudinal direction of the cable. Thereby, the support element is generally disc-shaped or flat.According to one embodiment, said struts extend generally in a radial direction perpendicular to the longitudinal direction of the cable. Thereby, the support element is generally disc-shaped or flat.

According to another ernbodiment, the struts extend with a sloping direction relative to the longitudinal direction of the cable. It is preferred that the support element is cone shaped as a consequence of the design of said struts. This design provides much longer interface between the support element and a ﬂuid inside the hollow room of the insulator than a disc-shaped support element. An interface between the support element and a ﬂuid, such as oil, in the hollow space of the insulator is almost parallel to the equal-potential lines in the area, i.e. Es along the interface is low. Therefone, the field distribution of the termination is only slightly affected by introduction of the support element.According to another ernbodiment, the struts extend with a sloping direction relative to the longitudinal direction of the cable. It is preferred that the support element is cone shaped as a consequence of the design of said struts. This design provides much longer interface between the support element and a ﬂ uid inside the hollow room of the insulator than a disc-shaped support element. An interface between the support element and a ﬂ uid, such as oil, in the hollow space of the insulator is almost parallel to the equal-potential lines in the area, i.e. Es along the interface is low. Therefone, the field distribution of the termination is only slightly affected by the introduction of the support element.

According to one embodiment, the termination arrangement comptises at least two support elements. Thereby, an improved stability and a ñrmer holding of the cable is achieved.According to one embodiment, the termination arrangement comptises at least two support elements. Thereby, an improved stability and an ñrmer holding of the cable is achieved.

It is preferred that the support element presents one or more openings that permit a ﬂuid inside the insulator to pass through the support element in a longitudinal direction of the insulator. Permission for a ﬂuid to pass the support element in the longitudinal direction is preferred since enclosure of the ﬂuid in separated rooms might result in different conditions in such rooms and less good performance of the ﬂuid in total.It is preferred that the support element presents one or more openings that permit a ﬂ uid inside the insulator to pass through the support element in a longitudinal direction of the insulator. Permission for a ﬂ uid to pass the support element in the longitudinal direction is preferred since enclosure of the ﬂ uid in separated rooms might result in different conditions in such rooms and less good performance of the ﬂ uid in total.

According to yet another embodiment, the insulator is filled with an electrically insulating ﬂuid in the region in which said spacing exists between the outer periphery of the cable and the inner periphery of the insulator. Preferably, said ﬂuid comprises oil or a gel. The ﬂuid has an electrically insulating function and also contributes to the cooling of the cable. It should also be mentioned that, preferably, the support element is made of an electrically insulating material, preferably a polymer.According to yet another embodiment, the insulator is filled with an electrically insulating ﬂ uid in the region in which said spacing exists between the outer periphery of the cable and the inner periphery of the insulator. Preferably, said ﬂ uid comprises oil or a gel. The ﬂ uid has an electrically insulating function and also contributes to the cooling of the cable. It should also be mentioned that, preferably, the support element is made of an electrically insulating material, preferably a polymer.

Further features of the present invention will be presented in the following detailed description of preferred embodiments.Further features of the present invention will be presented in the following detailed description of preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS The cable termination arrangement of the invention will now be described more in detail with reference to the annexed drawing, on which: Fig. la is a cross section of a tertnination arrangement according to the invention, Fig. lb is a cross section according to I-I in tig. la, Fig. 2a is a cross section of a terntination arrangement according to a second embodiment of the invention, Fig. 2b is a cross section according to II-II in ñg 2a, Fig. 3a is a cross section of a terinination arrangement according to a third embodiment of the invention, Fig. 3b is a cross section according to III-HI in ñg. 3a, Fig. 4a is a cross section of a termination arrangement according to a fourth embodiment of the invention, Fig. 4b is a cross section according to lV-IV in ﬁg. 4a, Fig. Sa is a cross section of a termination arrangement according to a ﬁfth embodiment of the invention, and Fig. Sb is a cross section according to V-V in ﬁg. Sa.LETTER DESCRIPTION OF THE DRAWINGS The cable termination arrangement of the invention will now be described more in detail with reference to the annexed drawing, on which: Fig. 1a is a cross section of a tertnination arrangement according to the invention, Fig. 1b is a cross section according to I-I in fig. la, Fig. 2a is a cross section of a terntination arrangement according to a second embodiment of the invention, Fig. 2b is a cross section according to II-II in ñg 2a, Fig. 3a is a cross section of a terinination arrangement according to a third embodiment of the invention, Fig. 3b is a cross section according to III-HI in ñg. 3a, Fig. 4a is a cross section of a termination arrangement according to a fourth embodiment of the invention, Fig. 4b is a cross section according to IV-IV in ﬁ g. 4a, Fig. Sa is a cross section of a termination arrangement according to a ﬁ fth embodiment of the invention, and Fig. Sb is a cross section according to V-V in ﬁ g. Sa.

DETAILED DESCRIPTION OF THE INVENTION Figs. la and lb present a ﬁrst embodiment of the cable termination arrangement according to the invention. The arrangement comprises an elongated hollow insulator l provided with sheds 2 as is well known within this field of technology. A cable 3 extends through the insulator l in the longitudinal direction of the latter. Apart from the end regions in which the cable 3 enters and exits the insulator l, and in which the cable 3 is held by the insulator l, there is spacing between the inner periphery of the insulator l and the outer periphery of the cable 3. The spacing is filled with oil or with a gel for the purpose of providing electric insulation and for promoting cooling of the cable 3.DETAILED DESCRIPTION OF THE INVENTION Figs. la and lb present a first embodiment of the cable termination arrangement according to the invention. The arrangement comprises an elongated hollow insulator l provided with sheds 2 as is well known within this field of technology. A cable 3 extends through the insulator l in the longitudinal direction of the latter. Apart from the end regions in which the cable 3 enters and exits the insulator l, and in which the cable 3 is held by the insulator l, there is spacing between the inner periphery of the insulator l and the outer periphery of the cable 3. The spacing is filled with oil or with a gel for the purpose of providing electrical insulation and for promoting cooling of the cable 3.

In the region in which there is spacing between the inner periphery of the insulator and the outer periphery of the cable there is provided a support element 4. The support element 4 hears on the outer periphery of the cable 3 and on the inner periphery of the insulator, thereby ñxing the position of the cable 3 in relation to the insulator 1 and pieventing misalignment of the cable 3. As a consequence of the provision of the support element, the cable 3 is held in coaxial relationship with the insulator 1. In other words, the cable 3 is prevented from being bent due to its own weight, which might otherwise be the case if the arrangement is placed in any other than vertical position.In the region in which there is spacing between the inner periphery of the insulator and the outer periphery of the cable there is provided a support element 4. The support element 4 hears on the outer periphery of the cable 3 and on the inner periphery of the insulator, thereby ñxing the position of the cable 3 in relation to the insulator 1 and pieventing misalignment of the cable 3. As a consequence of the provision of the support element, the cable 3 is held in coaxial relationship with the insulator 1. In other words, the cable 3 is prevented from being bent due to its own weight, which might otherwise be the case if the arrangement is placed in any other than vertical position.

The support element 4 is made of a dielectric material such as a polymer. In this first embodiment it comprises an inner ring 5 hearing on the outer periphery of the cable 3, an outer ring 6 hearing on the inner periphery of the insulator 1, and a plurality of struts 7 extendin g from the inner ring 5 to the outer ring 6. The support element 4 is generally disc-shaped. Accordingly, the struts 7 extend in a direction perpendicular to the longitudinal direction of the cable 3 and of the insulator 1. The support element 4 is located approximately half way between the en points in which the cable 3 is held by the insulator 1. There can be provided an engagement means formed by a small heel 12 on the inner periphery of the insulator 1 against which the support element hears and by which the support element is prevented from being displaced in the longitudinal direction of the cable 3.The support element 4 is made of a dielectric material such as a polymer. In this first embodiment it comprises an inner ring 5 hearing on the outer periphery of the cable 3, an outer ring 6 hearing on the inner periphery of the insulator 1, and a plurality of struts 7 extendin g from the inner ring 5 to the outer ring 6. The support element 4 is generally disc-shaped. Accordingly, the struts 7 extend in a perpendicular direction to the longitudinal direction of the cable 3 and of the insulator 1. The support element 4 is located approximately half way between the en points in which the cable 3 is held by the insulator 1. There can be provided an engagement means formed by a small heel 12 on the inner periphery of the insulator 1 against which the support element hears and by which the support element is prevented from being displaced in the longitudinal direction of the cable 3.

Figs. 2a and 2b show a second embodiment of the cable termination arrangernent according to the invention. This embodiment differs from that in figs. la and lb in that the support element 8 has a different design. The support element 8 presents an inner ring 9 hearing on the outer periphery of the cable 3, an outer ring 10 hearing on the inner periphery of the insulator l, and struts 11 extending from the inner ring 9 to the outer ring 10. The rings 9, 10 are displaced in relation to each other in the longitudinal direction of the cable 3. The struts 11 extend in a sloping direction relative to the longitudinal direction of the cable 3. Accordingly, the support element 8 has a conical shape. The support element 8 is located approximately half way between the end points in which the cable 3 is held by the insulator 1. As in the first embodiment there can be provided an engagement means formed by a small heel 12 on the inner periphery of the insulator 1 against which the support element 8 hears and by which the support element is prevented from being displaced in the longitudinal direction of the cable 3 Figs. 3a and 3b show a third embodiment, which differs from that in figs. 2a and 2b in that the support element 13 is of somewhat larger outer diameter and is located in another position along the cable 3 and is supported by a stress cone 15 provided on the outer periphery of the cable 3 instead of by any heel or the like provided on the inner periphery of the insulator 1.Figs. 2a and 2b show a second embodiment of the cable termination arrangernent according to the invention. This embodiment differs from that in figs. la and lb in that the support element 8 has a different design. The support element 8 presents an inner ring 9 hearing on the outer periphery of the cable 3, an outer ring 10 hearing on the inner periphery of the insulator l, and struts 11 extending from the inner ring 9 to the outer ring 10. The rings 9, 10 are displaced in relation to each other in the longitudinal direction of the cable 3. The struts 11 extend in a sloping direction relative to the longitudinal direction of the cable 3. Accordingly, the support element 8 has a conical shape. The support element 8 is located approximately half way between the end points in which the cable 3 is held by the insulator 1. As in the first embodiment there can be provided an engagement means formed by a small heel 12 on the inner periphery of the insulator 1 against which the support element 8 hears and by which the support element is prevented from being displaced in the longitudinal direction of the cable 3 Figs. 3a and 3b show a third embodiment, which differs from that in figs. 2a and 2b in that the support element 13 is of somewhat larger outer diameter and is located in another position along the cable 3 and is supported by a stress cone 15 provided on the outer periphery of the cable 3 instead of by any heel or the like provided on the inner periphery of the insulator 1.

Figs. 4a and 4b show a fourth ernbodiment, according to which there are provided two support elements of a design oorresponding to the design of the support element 8 shown in ñgs. 2a and 2b. In fact the embodiment corresponds to that in tig. 2a, but comprises a further support element 14 the inner ring of which is arranged opposite to and adjacent the inner ring 9 of the first support element 8. By the provision of this further support element 14 a more stable and finn holding of the cable 3 is achieved.Figs. 4a and 4b show a fourth ernbodiment, according to which there are provided two support elements of a design oorresponding to the design of the support element 8 shown in ñgs. 2a and 2b. In fact the embodiment corresponds to that in tig. 2a, but comprises a further support element 14 the inner ring of which is arranged opposite to and adjacent the inner ring 9 of the first support element 8. By the provision of this further support element 14 a more stable and finn holding of the cable 3 is achieved.

Fig. Sa and 5b shows a ﬁfth embodiment, which differs from that in ﬁg. 4a and 4b in that the outer rings, and not the inner rings, of the opposed support elements 8. 14 are turned towards each other. There is also a slight difference in the design of the support heel 12 on the inner periphery of the insulator 1.Fig. Sa and 5b shows a embodiment fth embodiment, which differs from that in ﬁ g. 4a and 4b in that the outer rings, and not the inner rings, of the opposed support elements 8. 14 are turned towards each other. There is also a slight difference in the design of the support heel 12 on the inner periphery of the insulator 1.

The support element 4, 8, 13, 14 in all embodiments present one or more openings 16 that permit a ﬂuid inside the insulator l to pass through the support elements 4, 8, 13, 14 in a longitudinal direction of the insulator 1.The support element 4, 8, 13, 14 in all embodiments present one or more openings 16 that permit a ﬂ uid inside the insulator l to pass through the support elements 4, 8, 13, 14 in a longitudinal direction of the insulator 1.

Claims

10 15 20 25 30 PATENT CLAIMS

1. A cable termination arrangement, comprising a hollow insulator (1) and a cable (3), said cable (3) extending through the insulator (l), and wherein the cable (3) extends with at spacing between its outer periphery and an inner periphery of the insulator (1) along at least a part of the length of the insulator (1), characterized in that, in said part in which there is a spacing between the outer periphery of the cable (3) and the inner periphery of the insulator (1), there is provided at least one support element (4, 8, 13, 14) that bears against the outer periphery of the cable (3) and against the inner periphery of the insulator (1) and holds the cable (3) in a predeterrnined position in relation to the insulator (l).

A cable termination arrangement according to claim l, characterized in that the support element (4, 8, 13, 14) presents at least two radial struts (7, 1 l), each strut extendiag between the outer periphery of the cable ( 3) and the inner periphery of the insulator (l).

A cable termination arrangement according to claim 2, characterized in that said struts (7) extend generally in a radial direction perpendicular to the longitudinal direction of the cable (3).

4. A cable tennination arrangement according to clam 2, characterized in that said struts (1 l) extend with a sloping direction relative to the longitudinal direction of the cable (3).

A cable termination arrangement according to claim 4, characterized in that the support element (4, 8, 13, 14) is cone shaped.

A cable termination arrangement according to claim 5, characterized in that it comprises at least two cone shaped support elements (8, 14). 10 15

A cable termination arrangement according to any one of claims 1-6, characterized in that the support element (4, 8, 13, 14) presents one or more openings that permit a ﬂ uid inside the insulator (1) to pass through the support element (4, 8, 13, 14) in a longitudinal direction of the insulator (l).

A cable termination arrangement according to any one of claims l-7, characterized in that the insulator (1) is filled with an electrically insulating ﬂ uid in the region in which said spacing exists between the outer periphery of the cable (3) and the inner periphery of the insulator (1).

9. A cable tennination arrangement according to claim 8, characterized in that said ﬂ uid comprises an oil or a gel.

A cable tertnination arrangement according to any one of claims l-9, characterized in that the cable (3) is a high voltage cable (3). 10 ABSTRACT A cable termination arrangement, comprising a hollow insu1ator (1) and a cable (3), said cable (3) extending through the insulator (1), and wherein the cable (3) extends with at spacing between its outer periphery and an inner periphery of the insulator (1) along at least a part of the length of the insulator (l). ln the part of the insulator (1) in which there is a spacing between the outer periphery of the cable (3) and the inner periphery of the insulator (1), there is provided at least one support element (4, 8, 13 , 14) that bears against the outer periphery of the cable (3) and against the inner periphery of the insulator (1) and holds the cable (3) in a predeterrnined position in relation to the insulator (1). (Fig. 1a) 10796EN Title: Cable termination device Summary: A cable termination device comprising a hollow insulator (1) and a cable (3), the cable (3) extending through the insulator (1), and the cable (3) extending with a space between its outer periphery and the inner periphery of the insulator (1) along at least a part of the length of the insulator (1). In the part of the insulator (1) where there is a space between its inner periphery and the outer periphery of the cable (3), at least one support element (4) is arranged which supports the outer periphery of the cable (3) and the inner periphery of the insulator (1) and holds the cable in a predetermined position relative to the insulator (1).