WO2013004681A2

WO2013004681A2 - Electrical external shielding for an electrical high-voltage connector, as well as electrical connecting unit

Info

Publication number: WO2013004681A2
Application number: PCT/EP2012/062878
Authority: WO
Inventors: Thilo Simonsohn
Original assignee: Tyco Electronics Raychem Gmbh
Priority date: 2011-07-04
Filing date: 2012-07-03
Publication date: 2013-01-10
Also published as: AU2012280375A1; ES2468115A2; GB2506813A; DE102011078612B3; ZA201400841B; WO2013004681A3; GB201401562D0; ES2468115R1; RU2598898C2; RU2014103579A; GB2506813B

Abstract

The present invention relates to an electrical external shielding (20) for an electrical high-voltage connector (10), particularly for mean-voltage applications in the electrical high-current range comprising a separate shield cover (200) which is configured in such a way that the shield cover (200) may be provided on the outside of the electrical high-voltage connector (10). The invention further relates to an electrical connecting unit (1) for distributing electrical energy for - as the case may be, preferably SF₆-gas-insulated - mean-voltage applications, internal applications, external applications in the high-current range comprising an electrical high-voltage connector (10) and an electrical external shielding (20) provided above or on it, the electrical external shielding (20) being configured according to the invention.

Description

Electrical external shielding for an electrical high-voltage connector, as well as electrical connecting unit

The present invention relates to an electrical external shielding for an electrical high-voltage connector, particu^¬ larly for mean-voltage applications in the high-current range. The present invention further relates to an electrical connecting unit for a distribution of electric energy for - as the case may be, preferably SF₆-gas-insulated - mean- voltage applications, internal or external high-current ap^¬ plications, comprising an electrical high-voltage connector and an electrical external shielding according to the inven^¬ tion .

Establishing electrical connections and sealing ends for mean- and high-voltage cables for high-current applications, e.g. by means of electrical connecting units, requires con^¬ siderable experience of a technician as well as precise han^¬ dling of the accessories and of the cable. The various manu^¬ facturers of accessories continually strive to develop mate^¬ rials, methods and products so that the setting-up of the connections and terminations for such cables only requires average manual skills and thus less mounting errors may occur apart from the setting-up procedure involving less time. In general, the manufacturer's developmental endeavours are such that current cable accessories for high voltages, i.e. elec- trie voltages of more than 1 kV, are based on standardized, custom-made components which are shrunk to, slid on or pressed on the prepared cables.

The problem with electric high voltages is that a conven- tional electrical isolator may become an electric conductor, whereby electrical leak currents and flashovers as well as corona discharge and ozone harmful to human health may occur. Thus, in the case of mean and high-voltage applications, even the most simple components have a critical significance which essentially contributes to the operating safety of said ap^¬ plication and to preventing damage. Thus, due care must be taken in the case of cable connections that neither air in^¬ clusions nor holes and/or imperfections occur in critical parts of the connection or, respectively, of the respective connecting units. Moreover, a concentration of electrical flux lines in boundary areas of the cable have to be avoided and potential electric discharges such as corona or spark discharges have to be taken into account.

Moreover, environmental interests have to be considered, wherein an electrical insulation of the cable must not be overtaxed by too strong electrical fields, as this may lead to fires in the vicinity. Due care must be taken particularly with respect to an effective and steadily reliable ground connection for a shielding of the cable and other metallic armouring and screens, whereby the penetration of moisture has to be prevented durably and safely. Moreover, electrical connections between the participating connecting units are to be installed which are effective and durably safe over the years, whereby uncovered electrical connections and bare metal parts have to be insulated and sealed off in order to prevent electric flashovers and breakdowns.

Electrical high-voltage connectors for mean- and high-voltage applications such as shielded (angular) plugs, adapter (plug) connectors and cable terminations comprise an electrical screen as an external shielding of the high-voltage connector or, respectively, of its connector body, the screen being provided externally and in most cases sputtered or sprayed on. In some applications, as the case may be, additional me^¬ tallic housings may be utilized into which the high-voltage connector may be inserted. It is the object of such high- voltage connectors to have an electrically sufficiently con^¬ ductive outer layer on the isolating connector body which un- der the respective environmental conditions roughly retains its properties, particularly an electrical resistance, over the entire period of use. Such periods of application usually amount to many years up to several decades.

Some specific regional demands to such external screens con^¬ sist in the screen having to withstand up to 80 A over a du^¬ ration of approximately 30 min during the occurrence of a ground fault. In view of such challenge, it is preferable to have a thick and electrically low-resistive outer screen on the high-voltage connector which may hardly be realized by means of sputtered-on screens. In this context, a metal hous^¬ ing is the means of choice. Moreover, sputtered-on screens, which are, however, mechanically more robust than sprayed-on screens, significantly increase the costs of the high-voltage connector since the material as well as a manufacturing proc^¬ ess to be used take a comparatively long time and are conse^¬ quently expensive. Moreover, disposal costs have to be taken into account which are also expensive for sputtered-on screens since the disposal of such materials or, respec^¬ tively, composites is complex.

Moreover, in the emergency of a ground fault, it is desirable to refit already installed high-voltage connectors in such a way that e.g. the above demands to current strength and time duration are met. Metal housings are in general an alterna^¬ tive to inmoulded and sputtered-on external screens; however, being heavy cast or formed components, these may only guaran^¬ tee a low laminar contact with the connector body of the high-voltage connector due to their mechanical rigidness. For this reason, a durable connection with good electrical con^¬ ductivity has to be implemented in this case which signifi^¬ cantly increases the mounting costs apart from the already high costs for a metal housing. Furthermore, the smallest a- chievable wall thicknesses of metal housings are over- dimensioned for such applications. Due to the demanded high endurance limits, electrical high- voltage connectors have to be resistant to the chemicals which may be present in the respective environment as well as to mechanical stress, which particularly concerns the outer screen. This is particularly a problem in the case of thin, i.e. inter alia sprayed-on screens. Furthermore, the manufac^¬ turing of a high-voltage connector should involve small cycle times and the high-voltage connector itself should be low in weight. Moreover, the high-voltage connector should pass what is referred to as a nail test, i.e. make sure that the high- voltage connector does not erroneously appear to be function^¬ ing after a defect.

It is thus the object of the invention to provide an electri- cal connecting unit or, respectively, an electrical high- voltage connector which provides an inexpensive and/or im^¬ proved alternative for connecting units or, respectively, high-voltage connectors having e.g. inmoulded or sputtered-on external screens. Furthermore, an inexpensive alternative for metal housings is to be provided, said alternative providing a higher mechanical flexibility than metal housings. Further^¬ more, it is the object to be solved by the invention to pro^¬ vide a possibility of refitting an already assembled connect^¬ ing unit or, respectively, an already integrated high-voltage connector with regard to high ground fault demands without having to disassemble it. Furthermore, a disadvantage de^¬ scribed above preferably with reference to a respective ap^¬ plication is to be avoided by means of the invention. The object of the present invention is solved by means of an electrical external shielding for an electrical high-voltage connector, particularly for mean-voltage applications in the high-current range, according to claim 1; and by means of an electrical connecting unit for distributing electric energy for - as the case may be, preferably SF₆-gas-insulated - mean-voltage applications, internal or external applications in the high-current range, according to claim 9. Advantageous embodiments, additional features and/or advantages of the in^¬ vention may be derived from the dependent claims and the fol^¬ lowing description. The electrical external shielding according to the invention comprises a shield cover configured, designed or composed in such a way that the shield cover may be provided on the out^¬ side of an electrical high-voltage connector for high elec^¬ tric currents. The electrical connecting unit according to the invention comprises an electrical high-voltage connector and an electrical external shielding according to the inven^¬ tion provided above or on it. In this context, the high- voltage connector may comprise an external shielding which is preferably configured as a screen deposited, particularly sprayed-on or sputtered-on, on an electrically insulating connector body of the high-voltage connector. Other methods for depositing such a screen configured as an external connector-body shielding may of course be used. As an alternative to the prior art, a more inexpensive prod^¬ uct is provided according to the present invention. The cost reduction is a result of providing an alternative to a thick, sputtered-on screen, wherein the high-voltage connector itself does not have to comprise any electrical screen or only a thin electrical screen on an outer surface. As a result, short cycle times and lower disposal costs than in the case of high-voltage connectors having a sputtered-on screen may be achieved during manufacturing. The external shielding according to the invention is suitable for refitting all in- stalled and uninstalled high-voltage connectors. Particu^¬ larly, it is possible by means of the embodiments of the pre^¬ sent invention to carry out a refit without disassembling already installed high-voltage connectors. The electrical shield cover or, respectively, external shielding according to the invention has a considerably lower weight than a metal housing and allows for a tightly fitting contact with the high-voltage connector. A material suitable for the preferably at least partially flexible shield cover may be any desired electrically conductive material. More^¬ over, electrically non-conductive materials may be used, wherein in such a case the shield cover has to be provided with an electrical screen on the outside, within or on the inside. If use is in this context made of metal conductors such as a shielding braid, the shield cover comprises superb properties for transporting high electric currents and thus meets the demands of a ground fault. The design of the shield cover may be adapted to any desired high-voltage connectors; of course, use may also be made of a universal design suit^¬ able for a plurality of high-voltage connectors.

According to the present invention, the electrical connecting unit or, respectively, the electrical high-voltage connector may be a mean-voltage connector, a basic connector/plug, a coupling connector/plug, a cable connector plug, a (shielded) plug, an adapter (plug) connector, a termination, a cable termination etc. for electrical high voltages, i.e. mean voltages and high voltages, which are, as the case may be, preferably configured for gas-proof applications. Fields of application of the connecting units are e.g. mean- or high- voltage applications, internal or external applications, par^¬ ticularly switch gears, switching devices, transformers, electric motors, disconnectors etc. In this context, the con^¬ necting unit or, respectively, the high-voltage connector may extend in a straight line or be configured angularly, wherein in the case of an angular embodiment, an angle of 90° is pre^¬ ferred. Correspondingly, the shield cover may have an I-, L-, T- or Y-shape.

In preferred embodiments of the invention, the at least par^¬ tially flexible electrical external shielding or, respec- tively, the shield cover comprises at least one closed sec^¬ tion in a circumferential direction and/or an open section in an axial direction. In this context, the shield cover may comprise an aperture in such a way that the shield cover may be slipped onto the high-voltage connector at least partially or at least in a section-wise manner with the aperture in front. Furthermore, the shield cover may comprise a plurality of shells and/or sleeves in such a way that the shells and/or sleeves may be positioned at or, respectively, on the high- voltage connector, wherein the shells and/or sleeves may preferably subsequently be joined to one another to result in an at least partially closed shield cover. In this context, the shells and/or sleeves are preferably configured in one material piece.

According to the invention, two shells associated with each other, particularly two unilaterally connected half-shells, of the shield cover may be connected to each other by means of mounting sections, particularly mounting strips. The mounting sections or, respectively, mounting strips are pref^¬ erably configured in such a way that they may be fixed to one another by means of one or a plurality of fastening means, particularly screws, bolts, rivets, clips and/or clamps.

Prior to and/or after assembly on the high-voltage connector, according to the invention the shield cover comprises at least one tube- and/or pipe-shaped section, wherein in the case of a plurality of tube- and/or pipe-shaped sections be- ing present, said sections are preferably in a direct fluid communication with one another, said fluid communication being filled by the high-voltage connector.

The shield cover may be configured in such a way that it may be assembled on a fully functional or, respectively, opera^¬ tional high-voltage connector or on an external connector- body shielding of the high-voltage connector or on an already operated or, respectively, installed high-voltage connector (retro-fit) . In this context, the shield cover is an external component which may be separated from the high-voltage con^¬ nector and preferably has a good electrical conductivity. Furthermore, the shield cover may comprise a plurality of in- dividual components which may be mechanically connected, glued and/or bonded to one another. Moreover, the shield cover may be an integrally configured component, particularly a materially integrally configured component, i.e. an inte- gral component .

The shield cover may be configured in such a way that one or a plurality of axial section (s) of the electrical high- voltage connector may in essence be entirely covered in a circumferential direction and/or generally covered in a lon^¬ gitudinal direction. In this context, it is preferable that an internal dimension of the shield cover is smaller in an unstressed, preferably unstretched, state than a correspond^¬ ing external dimension of the high-voltage connector. In this context, it is preferable that in essence all internal circumferential dimensions of the shield cover are smaller in an unstressed state than the corresponding external circum^¬ ferential dimensions of the high-voltage connector. Further^¬ more, essentially all axial dimensions of the shield cover may be smaller than the corresponding axial dimensions of the high-voltage connector. Furthermore, apart from a reduction factor, an internal contour of the shield cover is essentially similar to an outer contour of the high-voltage con^¬ nector .

In preferred embodiments of the invention, the shield cover comprises a layer with an electrically conductive layer, which may particularly be sprayed on, on its internal and/or external surface. Furthermore, the shield cover may comprise an electrically conductive shielding, particularly a prefera^¬ bly overmoulded or bonded shielding braid, which is prefera^¬ bly provided on the inner surface, within or at the outside surface of the shield cover. In particular by means of a shielding braid, high electric currents may durably be trans- mitted which in the case of a ground fault protects the elec^¬ trical high-voltage conductor and, as the case may be, the device or unit electrically connected thereto against damage. According to the present invention, the shield cover may comprise a grounding unit, particularly a grounding strap, a grounding eye or a grounding grommet . The grounding unit may be configured and/or provided at/in the shield cover in such a way that the grounding unit may be brought into electrical contact with a grounding unit of the connector body. In this context, the grounding unit of the shield cover may be con^¬ figured in such a way that it may be provided above the grounding unit of the connector body and thus, both compo^¬ nents may be grounded by means of one single shield or, re^¬ spectively, grounding line. The shield cover may be a con^¬ necting element which may be connected to a connecting ele^¬ ment of a second shield cover or of a second shield cover section of the same shield cover, the connecting elements be^¬ ing preferably configured in such a way that they engage in an electrically conductive connection. The second shield cover section may in this context be a component separate from the shield cover.

In preferred embodiments, the shield cover is a cast part, particularly an in ection-moulded part, which comprises a preferably elastic material, particularly a natural or a syn^¬ thetic polymer, preferably an elastomer. Correspondingly, the shield cover may comprise silicone, particularly silicone rubber, a rubber, particularly EPDM (ethylene propylene diene monomer), or a thermoplastic elastomer. In this context, the material of the shield cover may be an electrically conduc^¬ tive or an electrically non-conductive material. In the lat- ter case, the shield cover comprises a screen or a shielding braid. A layer thickness of the shield cover is preferably about 1 mm, about 2 mm, about 3 mm, about 4 mm, about 5 mm, about 6 mm or about 7 mm. In the following, the present invention will be described in more detail by means of embodiment examples in conjunction with the accompanying drawing. The schematic figures of the drawing show:

Fig. 1 a sectional lateral view of a connecting unit for

high-voltage and high-current applications comprising a sprayed-on screen as an external shielding;

Fig. 2 a lateral view of a first embodiment of a sectionally depicted external shielding according to the invention in a mounting position on a non-sectionally de- picted electrical high-voltage connector;

Fig. 3 in a view analogous to Fig. 2, a second embodiment of the external shielding according to the invention prior to arranging shells or, respectively, sections of the external shielding with regard to one another; Fig. 4 a front view of the external shielding of Fig. 3 sec^¬ tionally depicted in an area of the mounting unit of the external shielding and in a mounting position on the partially sectionally depicted high-voltage con^¬ nector ;

Fig. 5 a lateral view of a third embodiment of a sectionally depicted external shielding according to the invention in a mounting position on a non-sectionally depicted electrical base and coupling connector; and Fig. 6 a fourth embodiment of the external shielding accord- ing to the invention in a partially sectional lateral view, the external shielding being mounted on an electrical high-voltage connector.

In the following, the invention will be explained in more detail in conjunction with an angulate and shielded electrical high-voltage connector 10 (cf . Fig. 1) which, together with an external shielding 20 according to the invention (cf . Fig. 2 to 6), results in an electrical connecting unit 1 according to the invention. Here, Fig. 1 shows the high-voltage connec^¬ tor 10 suitable for up to 24 kV and 800 A in a detailed de^¬ piction, wherein the details have been omitted in the other Figs. 2 to 6. Of course, it is possible to transfer the in^¬ vention to other high-voltage connectors, as well (cf . abo^¬ ve) . The high-voltage connector 10 (cf . Fig. 1) comprises an elec^¬ trically insulating connector body 100 which is also referred to as a shielded plug part 100. The connector body 100 pref^¬ erably consists of a highly modified silicone rubber which is characterized by a high electrical stability, a high ductile yield as well as low flammability . The connector body 100 comprises a thin-walled, electrically conductive outer shell 110, which is referred to as connector body shielding 110, which is rigidly connected to the insulation of the high- voltage connector 10. Together with the internal electrically conductive parts of the high-voltage connector 10, it pro^¬ vides a controlled distribution of an electrical field of the high-voltage connector 10 and ensures that in case of a per^¬ son accidentally touching an energized contact, no danger will occur.

Presently, the connector body shielding 110 is configured as a shielding layer 110 sprayed on the connector body 100, the shielding layer 110 consisting of an electrically conductive silicone rubber. Of course, it is possible to use other shielding layers 110, even made of different materials, as the case may be. Preference is also made of inmoulded shield^¬ ing layers 100 by means of which a higher ampacity may be achieved, since such layers are thicker than sprayed-on shielding layers 110. Other methods for depositing the shielding layer 110 may of course be utilized. It is possible in the embodiments of the invention to entirely dispense with said shielding layer 100 and to merely use an electrically conductive external shielding 20 according to the invention. Furthermore, the connector body 100 comprises an internal connector body shielding 120 configured as an internal screen 120 , wherein said shielding 120 preferably consists of elec- trically conductive silicone rubber, as well. The internal connector body shielding 120 is configured as a Faraday cage 120 around a conductor contact 130, the Faraday cage 120 pre^¬ venting partial discharge together with the external shield- ing layer 110. The conductor contact 130 is preferably con^¬ figured as a screw cable lug 130 or a compression cable lug 130 comprising a shear-headed bolt for connecting aluminium- conductor 2 or copper-conductor high-voltage cables 2. A stress cone 140 located in a transitional area between a shielded and an unshielded area of the high-voltage cable 2 influences or, respectively, controls an electric field at a single wire shield edge of the high-voltage cable 2.

Moreover, the connector body 100 comprises a grounding unit 104 which is preferably configured as a grounding eye 104 and provides a grounding of the high-voltage connector 10. For this purpose, the grounding eye 104 is configured as a con^¬ necting point for a shield conductor 3. Within the connector body 100, an electrical contact unit 150 configured as a threaded 150 or a contact pin 150 is provided. A spring washer and a nut provide good electrical and mechanical con^¬ tact of the contact unit 150 to the conductor contact 130. Furthermore, the high-voltage connector 10 comprises a rear removable sealing plug 160 having a capacitive divider, wherein a capacitive checkpoint 162 may be used to ascertain whether a high-voltage conductor 10 or, respectively, a con^¬ tact implemented therewith is energized by a high voltage. An electrically conductive covering cap 170 serves as a shield^¬ ing and as a protective cap for of the sealing plug 160.

The electrical external shielding 20 according to the inven^¬ tion (cf. Figs. 2 to 6) serves, as well as the external screen 110 of the connector body 100, for transporting surface charge, for field distribution and for electromagneti- cally shielding the high-voltage connector 10, and comprises a shield cover 200, a shield envelope 200, a shield jacketing 200, a shield coating 200, a shield sleeve 200, a shield cov- ering 200, a shield sheathing 200, a shield cladding 200 or a shield tube 200. In the following, reference will only be made to a shield cover 200, wherein the preferably electri^¬ cally conductive shield cover 200 comprises an unstable, par- ticularly a flexible, soft, more or less smooth, elastic, yielding and/or bendable material.

The shield cover 200 is preferably cast and particularly in^¬ jection-moulded. However, a textile, i.e. a flexible material consisting of a fibre composite is suitable as a material for the shield cover 200, as well, as long as the textile is suf^¬ ficiently electrically conductive at least on its surface and may be provided above the high-voltage connector 10. If a shielding braid 220 (cf . below) is used, the electrical con- ductivity of the textile may be dispensed with. According to the invention, the electrical external shielding 20 or, re^¬ spectively, the shield cover 200 is used in addition to or as an alternative for the external connector body shielding 110, the shield cover 200 enveloping the connector body 100 along its axial 12, 14 or, respectively, longitudinal sections 12, 14 in the circumferential direction. In this context, it is preferred that the corresponding longitudinal sections of the shield cover 200 be a little shorter than the axial sections 12, 14 of the connector body 100.

A shape of the electrical external shielding 20 or, respec^¬ tively, of the shield cover 200 thereby corresponds to a shape of the connector body 100 or, respectively, to a shape of the high-voltage connector 10. Presently, this is a shape approximating a "T" or, respectively, an "L". Other shapes, particularly a linear configuration of the shield cover 200, may of course be used, even if the connector body is not con^¬ figured linearly. In such a case, the shield cover 200 only covers an axial section 12, 14 of the high-voltage connector 10. Preferably, the shield cover 200 is configured in such a way that it must be stretched in order to fit over the corre^¬ sponding axial sections 12, 14 of the connector body. This guarantees a tightly fitting shield cover 200, the shield cover 200 enveloping the connector body 100 like a skin.

It is furthermore preferred that the shield cover 200 be con- figured in a closed (cf. Figs. 2, 5 and 6) or closable manner (cf. Figs. 3 and 4), apart from a lateral aperture for the grounding eye 104 of the connector body 100. In this context, the shield cover 200 itself consists, depending on the shape of the connector body 100, of short tube- or pipe-like sec- tions or, respectively, areas which are blended with one an^¬ other, i.e. are in a fluid communication with one another. At its respective ends, the shield cover 200 comprises apertures 206 from which the high-voltage connector 10 or, respec^¬ tively, its connector body 100 and the electrical high- voltage cable 2 may at least partially protrude if the exter^¬ nal shielding 20 is a in the high-voltage connector 10.

According to the embodiment of the invention depicted in Fig. 2, the shield cover 200 is, apart from the aperture for the grounding eye 104, closed at its circumference, wherein the shield cover 200 may be slipped over the high-voltage connec^¬ tor 10 or, respectively, its connecting housing 100 via one of its apertures 206. For this purpose, the shield cover 200 has to be sufficiently elastically ductile in order to tightly fit the connector body 100 in the assembled state. A mounting of the electrical external shielding 20 may be car^¬ ried out if the high-voltage connector 10 is e.g. not mounted at a unit. I.e. the external shielding 20 may be assembled during the manufacturing of the high-voltage connector 10 or later during disassembly of an implemented electrical connec^¬ tion to the high-voltage connector 10.

For a ground connection, the shield cover 200 comprises a grounding unit 204 which may be configured as a grounding strap 204, a grounding eye 204 or a grounding grommet 204. A shield conductor 3 (not depicted in Figs. 2 to 5) may be electrically connected to said shield cover grounding 204. In embodiments of the present invention, the grounding unit 204 of the shield cover 200 may be provided adjacent to the grounding unit 104 of the connector body 100, a shared shield conductor 3 then grounding the electrical high-voltage con- nector 10 as well as the shield cover 200. In particular, the grounding unit 104 of the shield cover 200 may be configured and provided in such a way that it may be slipped over the grounding unit 104 of the connector body 100, which automati^¬ cally establishes an electrically conductive connection be- tween these components.

Figs. 3 and 4 depict another embodiment of the separate ex^¬ ternal shielding 20. Here, the individual axial sections 12, 14 of the shield cover 20 have been cut open longitudinally, wherein the steps necessary therefore have preferably been carried out at circumferential sections of the shield cover 200 directly adjacent to one another. In this embodiment, not all axial sections 12, 14 need to be cut open; it is entirely possible that a (partial) section is provided which is closed in the circumferential direction (not depicted) . By the proc^¬ ess of cutting open, shells 202, half-shells 202, sections 202 or areas 202 of the shield cover 200 result which are preferably integrally connected to one another at a side op^¬ posite to the corresponding cut. However, it is also possible to cut open the shield cover 200 at this position, as well, and to assemble the shield cover 200 at the high-voltage con^¬ nector 10 starting from two opposite sides (not shown) .

In order to arrange the shells 202 with regard to one an- other, the corresponding free circumferential longitudinal ends may e.g. comprise mounting sections 230 configured as mounting strips 230 which comprise one or a plurality of mounting units 232, particularly via apertures 232. By means of the mounting units 232, the two shells 202 may be arranged with regard to one another. Presently, this is done by fas^¬ tening means configured as screws 30, bolts 30, rivets 30 which are slid through coaxial via apertures 232. However, use may also be made of clips and clamps (not shown) or it is possible to bond two respective free circumferential longitu^¬ dinal ends of the shells 202. The embodiments according to Figs. 3 and 4 are particularly suitable for already mounted high-voltage connectors 10 since a mounting of such a shield cover 200 may be carried out without removing the high- voltage connector 10 from an existing connection.

Furthermore, the invention may be used for base 10 and cou- pling connectors 10, as shown in Fig. 5. Here, it is pre^¬ ferred that the two shield covers 200 of the base 10 and the coupling connector 10 are in electrically conductive contact with each other so that only one grounding unit 204 has to be provided. Said electrically conductive connection of the two shield covers 200 may e.g. be carried out by means of con^¬ necting elements 210, 212 which are in mechanical contact with one another. Such connecting elements 210, 212 may e.g. be straps 210, 212, a strap and a grommet (not shown) or parts of a latch (not shown, either) . Here, e.g. two straps 210, 212 which each comprise a via aperture may be electri^¬ cally and mechanically connected by means of a screw or a rivet .

Additionally or alternatively to its electrically conductive configuration, the shield cover 200 may comprise an electrically conductive shielding 220, as depicted in Fig. 6. Said shielding 220 may be provided on the inside or the outside of the shield cover 200; the shielding may also be located within the shield cover 200. In this context, the shielding 220 may be inserted in an injection mould for the shield cover 200, wherein the shield cover 200 is subsequently pro^¬ vided at/around the shielding 220. However, bonding to an outer or inner face of the shield cover 200 is conceivable, as well. Preferably, the shielding 220 is a shielding braid 220, a braided conductor 220 or a braiding. However, a configuration as an electrical screen 220 which is e.g. inter- nally or externally sprayed on, or individual electrical wires may be used, as well.

Such embodiments have superb electrical properties which are not subject to significant change even during long periods of time or will not deteriorate in such a way that the shield cover 200 becomes unusable. Particularly the use of a shield^¬ ing braid 220, e.g. of a copper net 220, sets up the shield cover 200 for high grounding demands. Such a shielding braid 220 comprises a certain ductility so that a shield cover 200 equipped with it may be slipped over a high-voltage connector 10. After mounting, the shielding braid 220 may be made to contract to result in a tightly fitting contact of the shield cover 200 and/or the shielding braid 220 with the high- voltage connector 10. The shielding braid 220 is connected to a shield conductor 3 (not shown) or, respectively, the indi^¬ vidual wires of the shielding braid 220 form the shield con^¬ ductor 3. A separate shield cover 200 according to the present inven^¬ tion is a one-piece or multi-part shield cover 200 which im^¬ proves the electrical properties of a high-voltage connector 10 being otherwise fully operable at least in the short run and preferably in the long run. I.e. in preferred embodiments of the invention, the shield cover 200 expands the electrical shielding properties of an external connector body shielding 110 of the high-voltage connector 10. If a multi-part shield cover 200 is used, the individual shells 202, half-shells 202, sections 202 and/or areas 202 may be bonded to one an- other and/or be mechanically connected to one another to re^¬ sult in the complete shield cover 200.

Claims

1. An electrical external shielding for an electrical high- voltage connector (10), particularly for mean-voltage appli^¬ cations in the electrical high-current range, comprising

a separate shield cover (200) configured in such a way that the shield cover (200) may be provided on the outside of the electrical high-voltage connector (10).

2. The electrical external shielding according to claim 1, the shield cover (200) comprising at least one closed section and/or at least one open section in a circumferential direc^¬ tion, the shield cover (200) particularly being a flexible shield cover (200) .

3. The electrical external shielding according to any one of the preceding claims, the shield cover (200) comprising an aperture (206) in such a way that the shield cover (200) may, aperture first, at least partially or at least in a section- wise manner be slipped over the high-voltage connector (10) .

4. The electrical external shielding according to any one of the preceding claims, the shield cover (200) comprising a plurality of shells (202) in such a way that the shells (202) may be positioned at or, respectively, on the high-voltage connector (10), wherein

the shells (202) may subsequently be joined to one an^¬ other to result in an at least partially closed shield cover (200) and at least a portion of the shells (202) are prefera^¬ bly configured in one material piece.

5. The electrical external shielding according to any one of the preceding claims, wherein two shells (202) of the shield cover (200) associated with each other may be connected to each other by means of mounting sections (230) provided thereon, wherein the mounting sections (230) are preferably configured in such a way that they may be fixed to one another by means of one or a plurality of fastening devices (30) .

6. The electrical external shielding according to any one of the preceding claims, wherein an internal dimension of the shield cover (200) is smaller in an unstressed state than a corresponding external dimension of the high-voltage connec^¬ tor (10), and/or

an axial dimension of the shield cover (200) of the ex^¬ ternal shielding (20) is smaller than a corresponding axial dimension of the high-voltage connector (10) .

7. The electrical external shielding according to any one of the preceding claims, wherein the shield cover (200) com^¬ prises a layer having an electrically conductive layer on its inner and/or on its outer face.

8. The electrical external shielding according to any one of the preceding claims, wherein the shield cover (200) com^¬ prises an electrically conductive shielding (220), particu^¬ larly a shielding braid (220), which is provided on the inner face, within and/or on the outer face of the shield cover (200) .

9. An electrical connecting unit for distributing electric energy for - as the case may be, preferably SF₆-gas-insulated - mean-voltage applications, internal applications or exter^¬ nal applications in the electrical high-current range com- prising

an electrical high-voltage connector (10) and an electri^¬ cal external shielding (20) provided above or on it, the electrical external shielding (20) being configured according to any one of the preceding claims.

10. The electrical connecting unit according to claim 9, the high-voltage connector (10) comprising an connector-body shi- elding (110) on its outer face, which

is preferably configured as a screen (110) deposited, and particularly sprayed or sputtered, onto an electrically insu^¬ lated connector body (100).