MODULE AND SYSTEM FOR BUILDING A VOLTAGE DIVIDER FOR SENSING A VOLTAGE

Abstract

The invention relates to a module (1) for building a voltage divider for sensing a voltage of an inner conductor of a high or medium voltage power conductor, wherein the module comprises: —at least one discrete impedance element (3), —a first connector (5) and a second connector (6), wherein the second connector is adapted to be mechanically and electrically connected with a connector identical to the first connector of a further module for building the voltage divider according to the invention, and wherein the first connector is adapted to be mechanically and electrically connected with a connector identical to the second connector of a further module for building the voltage divider according to the invention, —wherein the at least one impedance element is electrically connected with the first and the second connector, and —wherein the module further comprises mechanical fixing (21) means for fixing the module to a high or medium voltage power conductor.

Claims

1. A module (1) for building a voltage divider for sensing a voltage of an inner conductor of a high or medium voltage power conductor, the module comprising at least one discrete impedance element (3), a first connector (5) and a second connector (6), wherein the second connector is adapted to be mechanically and electrically connected with a connector identical to the first connector of a further module for building the voltage divider according to the invention, and wherein the first connector is adapted to be mechanically and electrically connected with a connector identical to the second connector of a further module for building the voltage divider according to the invention, wherein the at least one impedance element is electrically connected with the first and the second connector, and wherein the module further comprises mechanical fixing means (21) for fixing the module to a high or medium voltage power conductor.

2. The module according to claim 1, wherein the module (1) comprises two or more discrete impedance elements (3) that are electrically connected in series as to be operable as a voltage divider for sensing a voltage of an inner conductor of the high or medium voltage power conductor.

3. The module according to claim 1 or 2, wherein the module (1) comprises a printed circuit board (2) carrying the at least one discrete impedance element (3).

4. The module according to any of the preceding claims, wherein the module (1) comprises an encapsulation body (8), in which the at least one discrete impedance element (3) as well as the first and the second connector (5, 6) are encapsulated such that the first and the second connector are accessible from the outside of the module.

5. The module according to claim 4, wherein the module (1) comprises an additional housing (20) enclosing the encapsulation body (8) such that the first and the second connector (5, 6) are accessible from the outside of the module (1).

6. The module according to claim 5, wherein the additional housing (20) and/or the encapsulation body (8) comprises the mechanical fixing means for fixing the module to a high or medium voltage power conductor.

7. The module according to claim 5 or claim 6, wherein the additional housing (20) and/or the encapsulation body (8) comprises a receiving space (21) for receiving a section of the high or medium voltage conductor such that the additional housing and/or the encapsulation body surrounds the high or medium voltage power conductor.

8. The module according to any of the claims 5 to 7, wherein the additional housing (20) and/or the encapsulation body (8) comprises the shape of a termination skirt.

9. The module according to any of the preceding claims, wherein the discrete impedance elements (3) comprise one or more resistors, and/or one or more capacitors, and/or one or more inductances.

10. The module according to any of the preceding claims, wherein the discrete impedance elements (3) are arranged in the module (1) as a straight chain or as a z-shaped chain.

11. A module (1) according to any of the preceding claims in combination with a second module (1) according to any of the preceding claims, wherein the two modules are mechanically and electrically connected with each other such that their discrete impedance elements (3) are electrically connected in series as to be operable as a voltage divider for sensing a voltage of an inner conductor of the high or medium voltage power conductor.

12. A system for building a voltage divider for sensing a voltage of an inner conductor of a high or medium voltage power conductor, the system comprising: at least one module (1) for building a voltage divider for sensing a voltage of a high or medium voltage power conductor according to any of the claims 1 to 10, at least one high or medium voltage end module (30) providing an electrical connection from one of the first or second connectors (5, 6) of the module and the high or medium voltage power conductor (11), and at least one low voltage end module (40) providing a low voltage impedance element (3) and an electrical connection to ground or low voltage.

13. The system according to claim 12, wherein the number of modules (1) for building a voltage divider for sensing a voltage of a high or medium voltage power conductor according to claims 1 to 10 can be selected according to the application in that the sensor is used.

14. The system according to claim 12, wherein the low voltage end module (40) may provide an electrical connection to earth potential and at least one signal output.

15. A high or medium voltage grid with a high or medium voltage power conductor comprising at least one module for building a divider for sensing a voltage according to any of the claims 1 to 10.

16. A high or medium voltage grid with a high or medium voltage power conductor comprising a system for building a voltage divider for sensing a voltage according to any of the claims 12 to 14.

Description

[0044] The invention will now be described in more detail with reference to the following Figures exemplifying particular embodiments of the invention:

[0045] FIG. 1 a three dimensional schematic view of a module for building a voltage divider for sensing a voltage of an inner conductor of a high or medium voltage power conductor according to the invention;

[0046] FIG. 2 a three dimensional schematic view of a termination skirt with a module for building a voltage divider for sensing a voltage of an inner conductor of a high or medium voltage power conductor according to the invention;

[0047] FIG. 3 a three dimensional view of a high or medium voltage cable end with partially removed outer layers;

[0048] FIG. 4 a three dimensional view of the high or medium voltage cable of FIG. 3 with an insulation tube;

[0049] FIG. 5 a three dimensional view of the high or medium voltage cable of FIGS. 3 and 4 with a first termination skirt with a module for building a voltage divider for sensing a voltage of an inner conductor of a high or medium voltage power conductor according to the invention;

[0050] FIG. 6 a three dimensional view of the high or medium voltage cable of FIGS. 3 to 5 with the first termination skirt pushed onto the isolation tube and a second termination skirt;

[0051] FIG. 7 a three dimensional view of the high or medium voltage cable of FIGS. 3 to 6 with three termination skirts pushed onto the insolation tube;

[0052] FIG. 8 a three dimensional view of the high or medium voltage cable of FIG. 7 with a high or medium voltage end module and a low voltage end module (system for building a voltage divider for sensing a voltage of an inner conductor of a high or medium voltage power conductor according to the invention) and

[0053] FIG. 9 an electrical circuit diagram of the system for building a voltage divider for sensing a voltage of an inner conductor of a high or medium voltage power conductor according to the invention.

[0054] Herein below various embodiments of the present invention are described and shown in the drawings wherein like elements are provided with the same reference numbers.

[0055] FIG. 1 shows a three dimensional schematic view of a module 1 for building a voltage divider for sensing a voltage of an inner conductor of a high or medium voltage power conductor according to the invention. The module 1 comprises a support 2, for example a printed circuit board, with a plurality of discrete impedance elements 3. The plurality of discrete impedance elements 3 are electrically connected in series as to be operable as a voltage divider for sensing a voltage of an inner conductor of a high or medium voltage power conductor. The electrical connections 4 between the discrete impedance elements 3 are realised with conductive traces 4 on the support 2. The impedance elements 3 are arranged in an s-shaped or zig-zag shaped manor on the printed circuit board 2.

[0056] The module 1 further comprises a first connector 5 and a second connector 6. Both connectors 5 and 6 are electrically connected with the discrete impedance elements via conductive traces 7 on the support 2.

[0057] The second connector 6 is adapted to be mechanically and electrically connected with a connector identical to the first connector 5 of a further module for building a voltage divider according to the invention. The first connector 5 is adapted to be mechanically and electrically connected with a connector identical to the second connector 6 of a further module 1 for building a voltage divider according to the invention. This enables to build a chain of modules 1 according to the invention, wherein the discrete impedance elements of the modules will be electrically connected in series as to be operable as a voltage divider for sensing a voltage.

[0058] Finally, the module 1 according to the invention comprises an encapsulation body 8. The encapsulation body is dimensioned such that the first and the second connector 5 and 6 are still accessible from outside the encapsulation body such that they may be connected to another connector, e.g. from a further module 1. In the embodiment shown in FIG. 1 the encapsulation body 8 has a prismatic or box-shape. The encapsulation body 8 may have any other appropriate shape, such as for example a tubular shape. The encapsulation body 8 is made out of electrically insulating material. It may also be made out of a rigid material in order to protect the elements of the module 1 against mechanical and/or chemical impacts.

[0059] FIG. 2 is a three dimensional schematic view of a termination skirt 20 with a module 1 for building a voltage divider for sensing a voltage of an inner conductor of a high or medium voltage power conductor according to the invention. The skirt 20 comprises a flat ellipsoid shape or a disk shape with a through hole 21 in its middle. The through hole 21 is dimensioned and designed such as to receive a high or medium voltage power conductor. As can be seen in FIG. 2, the module 1 is embedded in the termination skirt 20 such that the two connectors 5 and 6 are accessible from the outside of the skirt 20 and may be mechanically and electrically connected with another connector, e.g. of a similar termination skirt 20 as shown in FIG. 2. Module 1 of FIG. 2 may also comprise a printed circuit board for carrying the impedance elements as well as an encapsulation body, over moulding the printed circuit board, as described above.

[0060] FIG. 3 is a three dimensional view of a high or medium voltage cable end of a high or medium voltage cable 10 with partially removed outer layers. The cable provides from the inside to the outside an inner high voltage or medium voltage conductor 11, a cable insulation 12 as well as a semi-conductive outer layer 13. Additional layers of the cable, like for example a cable sheath, are not shown in the drawing.

[0061] Moving further to FIG. 4, showing a three dimensional view of the end of the high or medium voltage cable 10 of FIG. 3 with an additional insulation tube 14 pushed over the inner conductor 11, the cable insulation 12 as well as the semi-conductive outer layer 13. The additional insulation tube 14 may comprise an inner field control layer (not shown in the drawing), for example a layer with a high permittivity and an outer insulation layer. The insulation tube 14 may be installed by a push on or a cold shrink installation.

[0062] FIG. 5 shows the high or medium voltage cable 10 of FIG. 4 together with the termination skirt 20 of FIG. 2. In order to install the termination skirt 20 on the additional insulation tube 14 of the high or medium voltage cable 10 either push on or cold shrink installation can be used. When a push on installation is used it may be necessary to apply an according grease on top of the additional insulation tube 14 to improve the sliding of the termination skirt 20 over the insulation tube 14. FIG. 6 shows the installed termination skirt 20 on the high or medium voltage cable 10 together if a second to be installed termination skirt 20. FIG. 7 shows the high or medium voltage cable 10 with three termination skirts 20. The termination skirts 20 are positioned over the additional insulation tube 14. They are mechanically and electrically connected with each other over the first and second connectors 5 and 6 of the module 1 for building a voltage divider for sensing a voltage according to the invention.

[0063] In FIG. 8 the high or medium voltage end module and the low voltage end module of the system for building a voltage divider for sensing a voltage of an inner conductor of a high or medium voltage power conductor are indicated. On top of the three termination skirts 20 the high or medium voltage end module 30 is indicated, which provides an electrical connection from the module 1 inside of the upper termination skirt 20 to the high or medium voltage cable conductor 11. On the lower side of the three termination skirts the low voltage end module 40 is indicated. It may provide a low voltage impedance. It is also possible, that the low voltage impedance element is integrated in the module 1 of the lower termination skirt 20. In this case the low voltage end module 40 comprises a connection to electrical ground and a signal output (not shown in the drawings). The signal output and the earth potential wires have to be installed on top of the semi-conductive layer 13 of the high or medium voltage cable 10 which has earth potential in order to avoid any discharges.

[0064] FIG. 9 is the electrical circuit diagram of the system for building a voltage divider for sensing a voltage of an inner conductor of a high or medium voltage power conductor shown in FIG. 8. From the top, the diagram shows the connection to the high or medium voltage conductor, the impedances for each of the three termination skirts, the signal output, the low voltage impedance as well as the connection to electrical ground.