WO2007147755A1 - A device for electric field control - Google Patents

A device for electric field control Download PDF

Info

Publication number
WO2007147755A1
WO2007147755A1 PCT/EP2007/055770 EP2007055770W WO2007147755A1 WO 2007147755 A1 WO2007147755 A1 WO 2007147755A1 EP 2007055770 W EP2007055770 W EP 2007055770W WO 2007147755 A1 WO2007147755 A1 WO 2007147755A1
Authority
WO
WIPO (PCT)
Prior art keywords
layer
conducting
insulating layer
triple point
resistive
Prior art date
Application number
PCT/EP2007/055770
Other languages
French (fr)
Inventor
Radim Lichy
Original Assignee
Abb Technology Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Abb Technology Ltd filed Critical Abb Technology Ltd
Priority to CA2653452A priority Critical patent/CA2653452C/en
Priority to CN200780020595.5A priority patent/CN101461110B/en
Priority to JP2009515827A priority patent/JP5512264B2/en
Priority to US12/305,956 priority patent/US8476526B2/en
Publication of WO2007147755A1 publication Critical patent/WO2007147755A1/en
Priority to US13/757,042 priority patent/US20130153267A1/en

Links

Classifications

    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02GINSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
    • H02G15/00Cable fittings
    • H02G15/08Cable junctions
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02GINSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
    • H02G15/00Cable fittings
    • H02G15/02Cable terminations
    • H02G15/06Cable terminating boxes, frames or other structures
    • H02G15/064Cable terminating boxes, frames or other structures with devices for relieving electrical stress
    • H02G15/068Cable terminating boxes, frames or other structures with devices for relieving electrical stress connected to the cable shield only
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02GINSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
    • H02G15/00Cable fittings
    • H02G15/08Cable junctions
    • H02G15/10Cable junctions protected by boxes, e.g. by distribution, connection or junction boxes
    • H02G15/103Cable junctions protected by boxes, e.g. by distribution, connection or junction boxes with devices for relieving electrical stress
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02GINSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
    • H02G15/00Cable fittings
    • H02G15/08Cable junctions
    • H02G15/18Cable junctions protected by sleeves, e.g. for communication cable
    • H02G15/184Cable junctions protected by sleeves, e.g. for communication cable with devices for relieving electrical stress
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K1/00Printed circuits
    • H05K1/02Details
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49002Electrical device making
    • Y10T29/4902Electromagnet, transformer or inductor
    • Y10T29/49071Electromagnet, transformer or inductor by winding or coiling
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49002Electrical device making
    • Y10T29/4902Electromagnet, transformer or inductor
    • Y10T29/49073Electromagnet, transformer or inductor by assembling coil and core
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49002Electrical device making
    • Y10T29/49082Resistor making
    • Y10T29/49087Resistor making with envelope or housing
    • Y10T29/49096Resistor making with envelope or housing with winding
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49002Electrical device making
    • Y10T29/49117Conductor or circuit manufacturing

Definitions

  • the present invention relates to a device for controlling an electric field at a high voltage component, said device comprising a resistive layer adapted, for field controlling purposes, to be arranged along a said component and which at one end is adapted to be electrically connected to a live high voltage part of the component and, at its other end, adapted to be electri- cally connected to ground potential, an insulating layer arranged on said resistive layer and extending outside thereof from said one end towards said other end while ending by a tapering field controlling geometry without reaching at a distance to said other end, as well as a semi-conducting or conducting layer arranged on the insulating layer and extending outside thereof past the end of the insulating layer towards said other end of the resistive layer, so that said resistive layer, said insulating layer and said semi-conducting or conducting layer meet at a triple point at said end of the insulating layer.
  • the high voltage component may carry an alternating voltage or a direct voltage, and it may for instance be a high voltage cable, in which the device may be used in a cable joint or a cable termination.
  • Other high voltage components are also conceivable, such as bushings in switchgears and vacuum breakers.
  • a device of this type is known through for instance WO 00/74191 A1 .
  • a device of this type is used for distributing the electric field where this is crucial and by that avoiding electric field concentrations and damaging of different type of equipments, such as cables.
  • the electric potential between the live part and ground is distributed by means of a material with a suitable resistance forming said resistive layer.
  • the device when using known electric field control devices of the type defined in the introduction for voltages above a determined limit, which is depending on the material used for the different layers, the device will be damaged limiting the use of such a device with respect to the level of said high voltage. It has turned out that the device will be damaged in the region of said triple point, where the insulating layer, the semi-conducting or conducting layer and the resistive layer meet.
  • This object is according to the invention obtained by providing such a device in which said resistive layer and said insulating layer are close to said end of the insulating layer designed so that the interface between these two layers ends in said triple point by making an angle to said semi-conducting or conducting layer of 60°-120°.
  • said angle of said interface strongly influences the behaviour of the materials in said triple point, and that considerably higher voltages may be taken by these materials without damaging the device in this region by selecting said an- gle within said interval thanks to the advantageous extension of the equipotential lines in the resistive layer and the insulating layer close to said triple point.
  • This also means that for a given voltage level less material may be used for said resistive layer while still being able to take the voltage, which results in a considerable reduction of costs, since this field controlling material is expensive.
  • This angle is preferably obtained by the new approach to work and shape the resistive field controlling layer at said triple point.
  • the resistive layer and said insulating layer are close to said end of the insulating layer designed so that said interface therebetween ends in said triple point by making a said angle to said semi-conducting or conducting layer of 70°-1 10°, advantageously 80°-100°, and preferably 85°-95°. It has been found that it is in most cases with respect to the stresses on said triple point most favourable to have said angle close to 90°, but angles within said intervals may be chosen for ease of manufacturing or other reasons while still giving the desired result with respect to preventing damage in the region of the triple point.
  • said insulating layer ends in the extension thereof from said one end to- wards said other end by a substantially sharp edge forming a transversal surface continuing into the resistive layer for forming a step in said resistive layer and making this thinner in the direction towards said other end for obtaining said angle in said triple point.
  • a device of this type is easy to manufacture and re- suits in comparatively small waste of the expensive field controlling material of said resistive layer.
  • said resistive layer has a recess in the region of said triple point receiving an end portion of said insulating layer for obtaining said angle in said triple point.
  • said resistive layer has a tip-like elevation in the region of said triple point with the tip ending in said triple point and having said insulating layer on one side thereof and said semi-conducting or conducting layer on the other side thereof for obtaining said angle in said triple point.
  • Such a tip-like elevation may be manufactured while very reliably defining said angle to the value desired, but the manufacturing thereof will result in a greater waste of said field controlling material than for the two previous embodiments.
  • said superimposed resistive layer, insulating layer and semi-conducting or conducting layer form a sleeve for receiving said high voltage component with the resistive layer being the innermost layer of the sleeve.
  • the device is adapted to control electric fields at high voltage components having an alternating voltage or a direct voltage on said live high voltage part, and it is adapted to control electric fields for high voltages being above 1 kV, above 50 kV, above 100 kV, 130 kV-400 kV, 200 kV-400 kV or 250 kV-350 kV.
  • the invention is the more interesting the higher the voltage is, although it may also be favourable for voltages being low in this context, which means for instance in the order of 10 kV.
  • the invention is especially applicable to voltages in the region of 100 kV-400 kV, for which damage of the region of said triple point constitutes an obstacle to raising the voltage further in for instance high volt- age cable joints or cable terminations.
  • the invention also relates to a cable joint for joining two high voltage DC-cables or AC-cables provided with a device for electric field control according to the invention, as well as a cable termination for terminating a high voltage DC-cable or AC-cable provided with a device for electric field control according to the invention.
  • a device for controlling an electric field of this type since they are often sensitive parts of a large power transmission system, in which there is an ongoing attempt to raise the voltages for reducing power losses.
  • the invention also relates to a method for manufacturing a device for controlling an electric field comprising the following steps: the resistive layer is wound around a carrier in a number of sub-layers and then ground to the desired shape, the insulat- ing layer is then wound outside the resistive layer in a number of sub-layers and then ground to the desired shape, and the semiconducting or conducting layer is wound in sub-layers outside the insulating layer and the resistive layer, and the resistive layer and/or the insulating layer are in the previous steps ground for obtaining said angle in said triple point.
  • Fig 1 is a cross-section view of a cable joint provided with an electric field control device according to an embodiment of the present invention
  • Fig 2-4 are enlarged simplified cross-section views of a part of electric field control devices according to different embodiments of the invention in the region of said triple point
  • Fig 5 and 6 are views of the embodiments according to fig 2 and 4 illustrating the extension of the equipotential lines in the case of a high voltage on a cable connected to the cable joint
  • Fig 5 and 6 are views of the embodiments according to fig 2 and 4 illustrating the extension of the equipotential lines in the case of a high voltage on a cable connected to the cable joint
  • Fig 7 is a simplified view illustrating a cable termination provided with an electric field control device according to an embodiment of the invention.
  • a cable joint 1 is shown in cross-section in fig 1 .
  • This cable joint has an inner resistive layer 2 with electric field controlling properties adapted to be arranged along a cable 3 and to be at one end 4 connected to a live high voltage part of the cable and at it's other end 5 electrically connected to ground potential by being connected to the outer semi-conducting sheath of the cable.
  • An insulating layer 6 is arranged outside the resistive layer and extend towards said other end 5 while ending by a tapering field controlling geometry 7 without reaching and at a distance to this end 5.
  • a semi-conducting or conducting layer 8 is arranged outside the insulating layer and extend past the end of the insulating layer towards said other end 5 of the resistive layer, so that the resistive layer, the insulating layer and the semi-conducting or the conducting layer meet at a triple point 9 at said end 10 of the in- sulating layer.
  • the material of the different layers 2, 6 and 8 may for example be EPDM-rubber or silicone rubber with different additives giving the different layers the properties desired.
  • a deflector 1 1 having nothing to do with the present invention is arranged in the region of the end of a live part of the respective cable for protection against discharges and the like.
  • the appearance of the resistive layer 2, the insulating layer 6 and the semi-conducting or conducting layer 8 in the region of said triple point 9 is shown by an enlargement A.
  • the live part or conductor 12 and the insulating layer or sheath 13 as well as the outer semi-conducting sheath 14 of the cable have been shown here, and in this figure and fig 3 and 4 only a half of one end of the cable joint is shown in cross-sec- tion.
  • Fig 3 is a view similar to fig 2 of an embodiment differing from the embodiment according to fig 2 by the fact that here a recess 20 has been created in said resistive layer close to the triple point 9 and this recess receives an end portion 21 of the insu- lating layer 6 for obtaining a said angle close to 90°.
  • Fig 4 shows how said angle in said triple point is instead obtained by providing the resistive layer with a tip-like elevation 17 with a tip defining said triple point with the insulating layer and the semi-conducting or conducting layer arranged on each side of said tip.
  • Fig 5 and 6 illustrates how the equipotential lines 18 will extend very smoothly in the region of said triple point 9 thanks to the appearance of this triple point with the angle between said interface 16 and said semi-conducting or conducting layer 8 close to 90°, such as 70-1 10°.
  • the voltages of said live part of the cable may be increased considerably with respect to cable joints according to the prior art without causing damage of the cable joint in the region of the triple point 9.
  • Fig 7 illustrates a cable termination 19 having an electric field control device according to the present invention, and parts of this device corresponding to such of the device according to fig 1 have been provided with the same reference numerals with addition of a prime. Said triple point is also crucial for the strength of such a cable termination, and the design of the different layers in connection with this triple point results in the same advantages as described above for a cable joint.

Landscapes

  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Insulation, Fastening Of Motor, Generator Windings (AREA)
  • Cable Accessories (AREA)
  • Control Of Eletrric Generators (AREA)

Abstract

A device for controlling an electric field at a high voltage comp o n e n t comprises a resistive layer (2) for field control, an insul a t i n g layer (6) arranged on said resistive layer and a semi-cond u c t i n g or conducting layer (8) arranged on the insulating layer. The three layers meet at a triple point (9) where the insulating layer ends. The interface between the resistive layer and the ins u l a t i n g layer makes in said triple point an angle to said semi-c o n d u c t i n g or conducting layer of 60° - 1 2 0° .

Description

A device for electric field control
TECHNICAL FIELD OF THE INVENTION AND PRIOR ART
The present invention relates to a device for controlling an electric field at a high voltage component, said device comprising a resistive layer adapted, for field controlling purposes, to be arranged along a said component and which at one end is adapted to be electrically connected to a live high voltage part of the component and, at its other end, adapted to be electri- cally connected to ground potential, an insulating layer arranged on said resistive layer and extending outside thereof from said one end towards said other end while ending by a tapering field controlling geometry without reaching at a distance to said other end, as well as a semi-conducting or conducting layer arranged on the insulating layer and extending outside thereof past the end of the insulating layer towards said other end of the resistive layer, so that said resistive layer, said insulating layer and said semi-conducting or conducting layer meet at a triple point at said end of the insulating layer.
The high voltage component may carry an alternating voltage or a direct voltage, and it may for instance be a high voltage cable, in which the device may be used in a cable joint or a cable termination. Other high voltage components are also conceivable, such as bushings in switchgears and vacuum breakers.
A device of this type is known through for instance WO 00/74191 A1 . A device of this type is used for distributing the electric field where this is crucial and by that avoiding electric field concentrations and damaging of different type of equipments, such as cables. The electric potential between the live part and ground is distributed by means of a material with a suitable resistance forming said resistive layer. By combining the resistive field control and a geometrical field control obtained through said insulating layer the risk of harmful charges building up and of high stresses upon said component, such as a cable, arising at rapid changes of the voltage thereof, is reduced with respect to such a device having only a resistive field control through a said resistive layer.
However, when using known electric field control devices of the type defined in the introduction for voltages above a determined limit, which is depending on the material used for the different layers, the device will be damaged limiting the use of such a device with respect to the level of said high voltage. It has turned out that the device will be damaged in the region of said triple point, where the insulating layer, the semi-conducting or conducting layer and the resistive layer meet.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an electric field control device of the type defined in the introduction which may be used for higher voltages than such electric field control devices already known without being damaged.
This object is according to the invention obtained by providing such a device in which said resistive layer and said insulating layer are close to said end of the insulating layer designed so that the interface between these two layers ends in said triple point by making an angle to said semi-conducting or conducting layer of 60°-120°.
It has been found that said angle of said interface strongly influences the behaviour of the materials in said triple point, and that considerably higher voltages may be taken by these materials without damaging the device in this region by selecting said an- gle within said interval thanks to the advantageous extension of the equipotential lines in the resistive layer and the insulating layer close to said triple point. This also means that for a given voltage level less material may be used for said resistive layer while still being able to take the voltage, which results in a considerable reduction of costs, since this field controlling material is expensive. This angle is preferably obtained by the new approach to work and shape the resistive field controlling layer at said triple point.
According to an embodiment of the invention the resistive layer and said insulating layer are close to said end of the insulating layer designed so that said interface therebetween ends in said triple point by making a said angle to said semi-conducting or conducting layer of 70°-1 10°, advantageously 80°-100°, and preferably 85°-95°. It has been found that it is in most cases with respect to the stresses on said triple point most favourable to have said angle close to 90°, but angles within said intervals may be chosen for ease of manufacturing or other reasons while still giving the desired result with respect to preventing damage in the region of the triple point.
According to another embodiment of the invention said insulating layer ends in the extension thereof from said one end to- wards said other end by a substantially sharp edge forming a transversal surface continuing into the resistive layer for forming a step in said resistive layer and making this thinner in the direction towards said other end for obtaining said angle in said triple point. A device of this type is easy to manufacture and re- suits in comparatively small waste of the expensive field controlling material of said resistive layer.
According to another embodiment of the invention said resistive layer has a recess in the region of said triple point receiving an end portion of said insulating layer for obtaining said angle in said triple point. According to another embodiment of the invention said resistive layer has a tip-like elevation in the region of said triple point with the tip ending in said triple point and having said insulating layer on one side thereof and said semi-conducting or conducting layer on the other side thereof for obtaining said angle in said triple point. Such a tip-like elevation may be manufactured while very reliably defining said angle to the value desired, but the manufacturing thereof will result in a greater waste of said field controlling material than for the two previous embodiments.
According to another embodiment of the invention said superimposed resistive layer, insulating layer and semi-conducting or conducting layer form a sleeve for receiving said high voltage component with the resistive layer being the innermost layer of the sleeve.
According to another embodiment of the invention the device is adapted to control electric fields at high voltage components having an alternating voltage or a direct voltage on said live high voltage part, and it is adapted to control electric fields for high voltages being above 1 kV, above 50 kV, above 100 kV, 130 kV-400 kV, 200 kV-400 kV or 250 kV-350 kV. The invention is the more interesting the higher the voltage is, although it may also be favourable for voltages being low in this context, which means for instance in the order of 10 kV. The invention is especially applicable to voltages in the region of 100 kV-400 kV, for which damage of the region of said triple point constitutes an obstacle to raising the voltage further in for instance high volt- age cable joints or cable terminations.
The invention also relates to a cable joint for joining two high voltage DC-cables or AC-cables provided with a device for electric field control according to the invention, as well as a cable termination for terminating a high voltage DC-cable or AC-cable provided with a device for electric field control according to the invention. These are two preferred uses of a device for controlling an electric field of this type, since they are often sensitive parts of a large power transmission system, in which there is an ongoing attempt to raise the voltages for reducing power losses.
The invention also relates to a method for manufacturing a device for controlling an electric field comprising the following steps: the resistive layer is wound around a carrier in a number of sub-layers and then ground to the desired shape, the insulat- ing layer is then wound outside the resistive layer in a number of sub-layers and then ground to the desired shape, and the semiconducting or conducting layer is wound in sub-layers outside the insulating layer and the resistive layer, and the resistive layer and/or the insulating layer are in the previous steps ground for obtaining said angle in said triple point.
Further advantages as well as advantageous features of the invention will appear from the following description.
BRIEF DESCRI PTION OF THE DRAWINGS
With reference to the appended drawings, below follow a specific description of embodiments of the invention cited as examples.
In the drawings:
Fig 1 is a cross-section view of a cable joint provided with an electric field control device according to an embodiment of the present invention,
Fig 2-4 are enlarged simplified cross-section views of a part of electric field control devices according to different embodiments of the invention in the region of said triple point, Fig 5 and 6 are views of the embodiments according to fig 2 and 4 illustrating the extension of the equipotential lines in the case of a high voltage on a cable connected to the cable joint, and
Fig 7 is a simplified view illustrating a cable termination provided with an electric field control device according to an embodiment of the invention.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
A cable joint 1 is shown in cross-section in fig 1 . This cable joint has an inner resistive layer 2 with electric field controlling properties adapted to be arranged along a cable 3 and to be at one end 4 connected to a live high voltage part of the cable and at it's other end 5 electrically connected to ground potential by being connected to the outer semi-conducting sheath of the cable.
An insulating layer 6 is arranged outside the resistive layer and extend towards said other end 5 while ending by a tapering field controlling geometry 7 without reaching and at a distance to this end 5.
A semi-conducting or conducting layer 8 is arranged outside the insulating layer and extend past the end of the insulating layer towards said other end 5 of the resistive layer, so that the resistive layer, the insulating layer and the semi-conducting or the conducting layer meet at a triple point 9 at said end 10 of the in- sulating layer. The material of the different layers 2, 6 and 8 may for example be EPDM-rubber or silicone rubber with different additives giving the different layers the properties desired.
A deflector 1 1 having nothing to do with the present invention is arranged in the region of the end of a live part of the respective cable for protection against discharges and the like. The appearance of the resistive layer 2, the insulating layer 6 and the semi-conducting or conducting layer 8 in the region of said triple point 9 is shown by an enlargement A. This corre- sponds to the embodiment shown in fig 2, which will now be described. The live part or conductor 12 and the insulating layer or sheath 13 as well as the outer semi-conducting sheath 14 of the cable have been shown here, and in this figure and fig 3 and 4 only a half of one end of the cable joint is shown in cross-sec- tion. It is shown how the insulating layer 6 ends by a substantially sharp edge forming a transversal surface 15 continuing into the resistive layer while making this thinner in the direction towards said other end 5. This result in an angle made by the interface between the resistive layer 2 and the insulating layer 6 to said semi-conducting or conducting layer 8 in said triple point of close to 90° resulting in the advantages described above. This geometry may be easily obtained by grinding the resistive layer and the insulating layer after having been wound as described above.
Fig 3 is a view similar to fig 2 of an embodiment differing from the embodiment according to fig 2 by the fact that here a recess 20 has been created in said resistive layer close to the triple point 9 and this recess receives an end portion 21 of the insu- lating layer 6 for obtaining a said angle close to 90°.
Fig 4 shows how said angle in said triple point is instead obtained by providing the resistive layer with a tip-like elevation 17 with a tip defining said triple point with the insulating layer and the semi-conducting or conducting layer arranged on each side of said tip.
Fig 5 and 6 illustrates how the equipotential lines 18 will extend very smoothly in the region of said triple point 9 thanks to the appearance of this triple point with the angle between said interface 16 and said semi-conducting or conducting layer 8 close to 90°, such as 70-1 10°. This means that for a given material and thickness of the resistive layer the voltages of said live part of the cable may be increased considerably with respect to cable joints according to the prior art without causing damage of the cable joint in the region of the triple point 9.
Fig 7 illustrates a cable termination 19 having an electric field control device according to the present invention, and parts of this device corresponding to such of the device according to fig 1 have been provided with the same reference numerals with addition of a prime. Said triple point is also crucial for the strength of such a cable termination, and the design of the different layers in connection with this triple point results in the same advantages as described above for a cable joint.
The invention is of course not in any way restricted to the embodiments described above, but many possibilities to modifications thereof would be apparent to a person with ordinary skill in the art without departing from the basic idea of the invention as defined in the appended claims.

Claims

Claims
1 . A device for controlling an electric field at a high voltage component (3), said device comprising
• a resistive layer (2) adapted, for field controlling purposes, to be arranged along a said component and which at one end (4) is adapted to be electrically connected to a live high voltage part (12) of the component and, at its other end (5), adapted to be electrically connected to ground potential,
• an insulating layer (6) arranged on said resistive layer and extending outside thereof from said one end towards said other end while ending (10) by a tapering field controlling geometry without reaching and at a distance to said other end, as well as
• a semi-conducting or conducting layer (8) arranged on the insulating layer and extending outside thereof past the end of the insulating layer towards said other end of the resistive layer, so that said resistive layer, said insulating layer and said semi-conducting or conducting layer meet at a triple point (9) at said end of the insulating layer,
characterized in that said resistive layer (2) and said insulating layer (6) are close to said end of the insulating layer designed so that the interface (16) between these two layers ends in said triple point by making an angle to said semi-conducting or conducting layer (8) of 60°-120°.
2. A device according to claim 1 , characterized in that said resistive (2) layer and said insulating layer (6) are close to said end of the insulating layer designed so that said interface (16) therebetween ends in said triple point (9) by making a said angle to said semi-conducting or conducting layer (8) of 70°-1 10°, advantageously 80°-100°, and preferably 85°-95°.
3. A device according to claim 1 or 2, characterized in that said insulating layer (6) ends in the extension thereof from said one end (4) towards said other end (5) by a substantially sharp edge forming a transversal surface (15) continuing into the resistive layer (2) for forming a step in said resistive layer and making this thinner in the direction to- wards said other end for obtaining said angle in said triple point (9).
4. A device according to claim 1 or 2, characterized in that said resistive layer (2) has a recess (20) in the region of said triple point (9) receiving an end portion (21 ) of said insulating layer (6) for obtaining said angle in said triple point.
5. A device according to claim 1 or 2, characterized in that said resistive layer (2) has a tip-like elevation (17) in the region of said triple point (9) with the tip ending in said triple point and having said insulating layer (6) on one side thereof and said semi-conducting or conducting layer (8) on the other side thereof for obtaining said angle in said triple point.
6. A device according to any of the preceding claims, characterized in that said superimposed resistive layer (2), insulating layer (6) and semi-conducting or conducting layer (8) form a sleeve for receiving said high voltage component with the resistive layer being the innermost layer of the sleeve.
7. A device according to any of the preceding claims, charac- terized in that it is adapted to control electric fields at high voltage components having an alternating voltage or a di- rect voltage on said live high voltage part, and that it is adapted to control electric fields for high voltages being above 1 kV, above 50 kV, above 100 kV, 130 kV-400 kV, 200 kV-400 kV or 250 kV-350 kV.
8. A cable joint for joining two high voltage DC-cables or AC- cables, characterized in that it is provided with a device for electric field control according to any of claims 1 -7 at each end thereof.
9. A cable termination for terminating a high voltage DC-cable or AC-cable, characterized in that it is provided with a device for electric field control according to any of claims 1 -7.
10. A method for producing a device for controlling an electric field according to any of claims 1 -7, characterized in that it comprises the following steps:
a) the resistive layer (2) is wound around a carrier in a num- ber of sub-layers and then ground to the desired shape, b) the insulating layer (6) is then wound outside the resistive layer in a number of sub-layers and then ground to the desired shape, and c) the semi-conducting or conducting layer (8) is wound in sub-layers outside the insulating layer (6) and the resistive layer (2), and that the resistive layer (2) and/or the insulating layer (6) are in step a) and b) ground for obtaining said angle in said triple point.
PCT/EP2007/055770 2006-06-12 2007-06-12 A device for electric field control WO2007147755A1 (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
CA2653452A CA2653452C (en) 2006-06-21 2007-06-12 A device for electric field control
CN200780020595.5A CN101461110B (en) 2006-06-21 2007-06-12 A device for electric field control, cable joint, cable terminator and method for producing the device
JP2009515827A JP5512264B2 (en) 2006-06-21 2007-06-12 Devices for electric field control
US12/305,956 US8476526B2 (en) 2006-06-21 2007-06-12 Device for electric field control
US13/757,042 US20130153267A1 (en) 2006-06-12 2013-02-01 Device for electric field control

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP06115839.0 2006-06-12
EP06115839A EP1870975B1 (en) 2006-06-21 2006-06-21 A device for electric field control

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US13/757,042 Continuation US20130153267A1 (en) 2006-06-12 2013-02-01 Device for electric field control

Publications (1)

Publication Number Publication Date
WO2007147755A1 true WO2007147755A1 (en) 2007-12-27

Family

ID=36694356

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2007/055770 WO2007147755A1 (en) 2006-06-12 2007-06-12 A device for electric field control

Country Status (8)

Country Link
US (2) US8476526B2 (en)
EP (1) EP1870975B1 (en)
JP (1) JP5512264B2 (en)
CN (1) CN101461110B (en)
AT (1) ATE476775T1 (en)
CA (1) CA2653452C (en)
DE (1) DE602006015937D1 (en)
WO (1) WO2007147755A1 (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101902024A (en) * 2008-12-09 2010-12-01 Abb研究有限公司 Flexible joint with resistive field grading material for HVDC cables and method for connecting same to HVDC cables
US8525025B2 (en) 2010-05-21 2013-09-03 Abb Research Ltd. High voltage direct current cable termination apparatus
US8609987B2 (en) 2010-05-21 2013-12-17 Abb Research Ltd. High voltage direct current cable termination apparatus
US8754329B2 (en) 2010-05-21 2014-06-17 Abb Research Ltd. High voltage direct current cable termination apparatus
US8946552B2 (en) 2010-05-21 2015-02-03 Abb Research Ltd. High voltage direct current cable termination apparatus
US9263875B2 (en) 2011-07-05 2016-02-16 Abb Research Ltd. Device for electric field control
EP3034561A1 (en) 2014-12-19 2016-06-22 ABB Technology AG A method of manufacturing a high-voltage DC cable joint, and a high-voltage DC cable joint.
WO2018228897A1 (en) 2017-06-16 2018-12-20 Benestad Solutions As High voltage wet-mate connection assembly

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102008009333A1 (en) * 2008-02-14 2009-08-20 Lapp Insulator Gmbh & Co. Kg Field-controlled composite insulator
EP2026438A1 (en) * 2008-05-26 2009-02-18 ABB Research LTD A cable connection electric field control device, and a cable connection arrangement provided therewith
DE202009018068U1 (en) 2009-06-02 2010-12-23 Solon Se solar module
EP2854247B1 (en) 2013-09-27 2016-12-28 Siemens Aktiengesellschaft Method for manufacturing a conductor part
US9306340B2 (en) * 2013-12-13 2016-04-05 General Electric Company System and method for sub-sea cable termination
KR102386760B1 (en) 2014-11-26 2022-04-14 엘에스전선 주식회사 Joint for High-Voltage Direct Current
CN108233321A (en) * 2018-02-26 2018-06-29 国网江西省电力有限公司电力科学研究院 A kind of integral prefabricated rubber insulators of cable
CN108962515B (en) * 2018-06-21 2022-04-29 深圳市沃尔核材股份有限公司 High-voltage bushing and cable terminal with uniform electric field function
DE102018116416A1 (en) * 2018-07-06 2020-01-09 Nkt Gmbh & Co. Kg coupling sleeve
JP2022002424A (en) * 2018-09-28 2022-01-06 住友電気工業株式会社 Rubber unit, cable connection structure, manufacturing method of rubber unit and manufacturing method of cable connection structure
EP3719372B1 (en) * 2019-04-02 2023-06-07 Crompton Technology Group Limited Electrical isolator
EP3799239A1 (en) * 2019-09-27 2021-03-31 Siemens Aktiengesellschaft Electrical conductor arrangement

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0683557A1 (en) * 1994-05-19 1995-11-22 PIRELLI CAVI S.p.A. Production process for elastomer sleeves for covering electric cable joints and associated sleeve
WO2000074191A1 (en) * 1999-05-28 2000-12-07 Abb Ab Control of electric field at direct voltage
US20040099434A1 (en) * 2000-04-25 2004-05-27 Luca Balconi Method for protecting joints for electrical cables, protective coating for said joints and joints thus protected

Family Cites Families (33)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1585124A (en) * 1924-09-18 1926-05-18 Standard Underground Cable Co Canada Cable joint
US1987918A (en) * 1932-06-21 1935-01-15 Standard Underground Cable Co Canada Electrical conductor
NL83230C (en) * 1950-01-25
US2790842A (en) * 1955-10-03 1957-04-30 G & W Electric Speciality Co Insulator for high voltage cable terminator or bushing
US3051770A (en) * 1959-08-26 1962-08-28 Pirelli Normal joint for high tension cables and process of making the same
US3254150A (en) * 1961-07-24 1966-05-31 Westinghouse Electric Corp Electrical coils for refrigerating apparatus
US3297970A (en) * 1965-04-07 1967-01-10 Gen Electric Electrical coil and method of manufacturing
US4099021A (en) * 1970-04-24 1978-07-04 Amerace Corporation Method of splicing high voltage shielded cables and splice connector therefor
FR2265197B1 (en) * 1974-03-19 1977-10-07 Thomson Csf
US4034151A (en) * 1975-05-14 1977-07-05 Amerace Corporation Splice connector with internal heat transfer jacket
US4192964A (en) * 1978-05-11 1980-03-11 Burndy Corporation Modifiable stop element for cable connector assemblies
US4383131A (en) * 1978-09-14 1983-05-10 Raychem Limited Shielded electrical cable joints and terminations and sleeve and method for forming same
JPS5925520A (en) * 1982-07-28 1984-02-09 日立電線株式会社 Electric field alleviating cable terminating unit
JPS6154813A (en) 1984-08-24 1986-03-19 日立電線株式会社 Insulating connector of cable
JPS61185229A (en) 1985-02-13 1986-08-18 松下電器産業株式会社 Electromotive cooker
JPS61185229U (en) * 1985-05-10 1986-11-19
US4822952A (en) * 1985-08-21 1989-04-18 Cable Technology Laboratories, Inc. Electrical cable joint and electrical cable termination and methods of making same
US5107076A (en) * 1991-01-08 1992-04-21 W. L. Gore & Associates, Inc. Easy strip composite dielectric coaxial signal cable
DE19513618A1 (en) * 1995-04-10 1996-10-17 Rxs Schrumpftech Garnituren Cable muff for joining conductors of medium tension screened cable
JPH10201073A (en) 1997-01-08 1998-07-31 Fujikura Ltd Middle connection of power cable
JPH1141779A (en) 1997-07-18 1999-02-12 Furukawa Electric Co Ltd:The Connection part for cross-linked polyethylene insulated power cable
JPH1169593A (en) 1997-08-14 1999-03-09 Furukawa Electric Co Ltd:The Production of rubber stress cone
US6514608B1 (en) * 1998-07-10 2003-02-04 Pirelli Cable Corporation Semiconductive jacket for cable and cable jacketed therewith
US6501024B1 (en) * 1999-01-07 2002-12-31 Pirelli Cables (2000) Limited Termination for electrical cable
US6193743B1 (en) * 1999-02-18 2001-02-27 Intermedics Inc. Apparatus for manufacturing an endocardial defibrillation lead with multi-lumen lead body and method
US6524702B1 (en) * 1999-08-12 2003-02-25 Dow Global Technologies Inc. Electrical devices having polymeric members
EP1195872B1 (en) * 2000-10-05 2004-03-03 Nexans Cable joint with improved screen connection
JP3786857B2 (en) 2001-10-15 2006-06-14 株式会社フジクラ Plastic insulated power cable connection using pre-molded rubber insulation cylinder
WO2004040730A1 (en) * 2002-10-30 2004-05-13 Pirelli & C. S.P.A. Process for manufacturing the elastomeric sleeve of a joint for electrical cables and manufacturing apparatus thereof
JP2004274913A (en) 2003-03-10 2004-09-30 Exsym Corp Intermediate connection for power cable
JP4158904B2 (en) * 2003-04-18 2008-10-01 古河電気工業株式会社 Normal temperature shrinkable rubber unit
FR2883425B1 (en) * 2005-03-21 2007-05-04 Nexans Sa SYNTHETIC END OF ELECTRIC CABLE FOR CONTINUOUS VOLTAGE
US7634852B2 (en) * 2006-08-04 2009-12-22 General Electric Company Method for manufacturing liquid-cooled stator bars

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0683557A1 (en) * 1994-05-19 1995-11-22 PIRELLI CAVI S.p.A. Production process for elastomer sleeves for covering electric cable joints and associated sleeve
WO2000074191A1 (en) * 1999-05-28 2000-12-07 Abb Ab Control of electric field at direct voltage
US20040099434A1 (en) * 2000-04-25 2004-05-27 Luca Balconi Method for protecting joints for electrical cables, protective coating for said joints and joints thus protected

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101902024A (en) * 2008-12-09 2010-12-01 Abb研究有限公司 Flexible joint with resistive field grading material for HVDC cables and method for connecting same to HVDC cables
US8525025B2 (en) 2010-05-21 2013-09-03 Abb Research Ltd. High voltage direct current cable termination apparatus
US8609987B2 (en) 2010-05-21 2013-12-17 Abb Research Ltd. High voltage direct current cable termination apparatus
US8754329B2 (en) 2010-05-21 2014-06-17 Abb Research Ltd. High voltage direct current cable termination apparatus
US8946552B2 (en) 2010-05-21 2015-02-03 Abb Research Ltd. High voltage direct current cable termination apparatus
EP2922164A1 (en) 2010-05-21 2015-09-23 ABB Research Ltd. A high voltage direct current cable termination apparatus
US9263875B2 (en) 2011-07-05 2016-02-16 Abb Research Ltd. Device for electric field control
EP3034561A1 (en) 2014-12-19 2016-06-22 ABB Technology AG A method of manufacturing a high-voltage DC cable joint, and a high-voltage DC cable joint.
US10250021B2 (en) 2014-12-19 2019-04-02 Nkt Hv Cables Gmbh Method of manufacturing a high-voltage DC cable joint, and a high-voltage DC cable joint
WO2018228897A1 (en) 2017-06-16 2018-12-20 Benestad Solutions As High voltage wet-mate connection assembly
US10916881B2 (en) 2017-06-16 2021-02-09 Benestad Solutions As High voltage wet-mate connection assembly

Also Published As

Publication number Publication date
EP1870975B1 (en) 2010-08-04
EP1870975A1 (en) 2007-12-26
CA2653452A1 (en) 2007-12-27
CA2653452C (en) 2014-09-30
JP5512264B2 (en) 2014-06-04
CN101461110B (en) 2011-08-24
US8476526B2 (en) 2013-07-02
DE602006015937D1 (en) 2010-09-16
CN101461110A (en) 2009-06-17
JP2009542173A (en) 2009-11-26
US20100288527A1 (en) 2010-11-18
ATE476775T1 (en) 2010-08-15
US20130153267A1 (en) 2013-06-20

Similar Documents

Publication Publication Date Title
US8476526B2 (en) Device for electric field control
US9263875B2 (en) Device for electric field control
JP2014518500A5 (en)
JP4778336B2 (en) Synthetic material end of DC electric cable
US8785780B2 (en) Electrical termination for extra high voltage
EP1188209B1 (en) Control of electric field at direct voltage
CN104756337B (en) Lightning protection device with insulated lead
US20190379198A1 (en) Multilayer stress control article and dry termination for medium and high voltage cable applications
JP2008535448A (en) Lightning strike current emission device
US9728305B2 (en) Apparatus for electric stress grading with wildlife guard for electrical power distribution equipment
JP4103259B2 (en) Lightning protection lead and lightning protection system
CA2821281A1 (en) Stress control device
JP5825874B2 (en) Termination part of power cable and assembling method of termination part
EP1056162A3 (en) Control of field at high voltage
US20160262373A1 (en) Active electrostatic wildlife guard for electrical power distribution equipment
CN109802351A (en) Dry type cable termination and CA cable assembly and its manufacture, assembling or improved method
WO2010149229A1 (en) An electrical cable
DE102011108391A1 (en) Arrangement for connecting ends of insulated leads of lightning protection system, has coupling piece that establishes electrical contact with semi-conductive or conductive cladding and current-carrying inner conductors of leads
JP3058547U (en) Lightning conductor
CA3082142A1 (en) Inductor to control transient currents during energized bond on

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 200780020595.5

Country of ref document: CN

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 07730092

Country of ref document: EP

Kind code of ref document: A1

DPE1 Request for preliminary examination filed after expiration of 19th month from priority date (pct application filed from 20040101)
WWE Wipo information: entry into national phase

Ref document number: 8874/DELNP/2008

Country of ref document: IN

WWE Wipo information: entry into national phase

Ref document number: 2653452

Country of ref document: CA

WWE Wipo information: entry into national phase

Ref document number: 12305956

Country of ref document: US

WWE Wipo information: entry into national phase

Ref document number: 2009515827

Country of ref document: JP

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 07730092

Country of ref document: EP

Kind code of ref document: A1