WO2022069332A1 - Appareil haute tension sous enveloppe et transformateur de courant pour l'appareil haute tension sous enveloppe - Google Patents

Appareil haute tension sous enveloppe et transformateur de courant pour l'appareil haute tension sous enveloppe Download PDF

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Publication number
WO2022069332A1
WO2022069332A1 PCT/EP2021/076157 EP2021076157W WO2022069332A1 WO 2022069332 A1 WO2022069332 A1 WO 2022069332A1 EP 2021076157 W EP2021076157 W EP 2021076157W WO 2022069332 A1 WO2022069332 A1 WO 2022069332A1
Authority
WO
WIPO (PCT)
Prior art keywords
coil
current transformer
current
voltage device
encapsulated high
Prior art date
Application number
PCT/EP2021/076157
Other languages
German (de)
English (en)
Inventor
Marina Helmig
Thomas Hilker
Henry JENICHEN
Dirk SCHRÄDER
Original Assignee
Siemens Energy Global GmbH & Co. KG
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 Siemens Energy Global GmbH & Co. KG filed Critical Siemens Energy Global GmbH & Co. KG
Publication of WO2022069332A1 publication Critical patent/WO2022069332A1/fr

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F38/00—Adaptations of transformers or inductances for specific applications or functions
    • H01F38/20—Instruments transformers
    • H01F38/22—Instruments transformers for single phase ac
    • H01F38/28—Current transformers
    • H01F38/30—Constructions
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
    • G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
    • G01R15/18—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using inductive devices, e.g. transformers
    • G01R15/181—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using inductive devices, e.g. transformers using coils without a magnetic core, e.g. Rogowski coils
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F5/00—Coils
    • H01F5/02—Coils wound on non-magnetic supports, e.g. formers
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02B—BOARDS, SUBSTATIONS OR SWITCHING ARRANGEMENTS FOR THE SUPPLY OR DISTRIBUTION OF ELECTRIC POWER
    • H02B13/00—Arrangement of switchgear in which switches are enclosed in, or structurally associated with, a casing, e.g. cubicle
    • H02B13/02—Arrangement of switchgear in which switches are enclosed in, or structurally associated with, a casing, e.g. cubicle with metal casing
    • H02B13/035—Gas-insulated switchgear
    • H02B13/0356—Mounting of monitoring devices, e.g. current transformers

Definitions

  • the invention relates to a current transformer for encapsulated high-voltage devices and an encapsulated high-voltage device with the current transformer, the current transformer having at least one coil which is arranged around at least one current-carrying conductor, the at least one current-carrying conductor being arranged in an encapsulating housing.
  • High-voltage devices are designed for voltages in a two-digit kilovolt range up to a voltage range of a few hundred kilovolts, in particular 1200 kV, and for currents in the range of up to a few hundred kiloamperes.
  • High voltage devices include e.g. B. Switchgear with high-voltage circuit breakers, isolators, transformers, arresters, instrument transformers and/or bushings .
  • Switchgear are e.g. B. Outdoor switchgear and/or gas-I insulated switchgear, d . H . Gas-insulated switch gears, which as a live tank, i . H . at high voltage potential, with a switching unit in an I solator, such as. B. arranged in a ribbed ceramic, silicone and/or composite material insulator housing, or as a dead tank, d. H . are arranged with a switching unit in a grounded housing, in particular in the form of a boiler.
  • the measurement of electrical currents in encapsulated high-voltage devices is essential for the operation of the devices, in particular for monitoring, controlling and/or regulating.
  • Electric currents in the field of encapsulated high-voltage devices are z. B. measured with inductive plug-in current transformers, which are arranged around current-carrying conductors of the high-voltage device.
  • This current transformer type consists of a Toroidal core with secondary winding, which is arranged concentrically around the current-carrying conductor.
  • the toroidal core is made of high-quality sheet metal with high permeability and is provided with a corresponding secondary winding in particular.
  • Push-through current transformers have a high intrinsic weight and require a large installation space, are associated with high costs, in particular due to the toroidal core, and have frequency- and amplitude-dependent non-linearities.
  • the object of the present invention is to specify a current transformer for encapsulated high-voltage devices and an encapsulated high-voltage device with the current transformer, which solve the problems described above.
  • the task is to specify a current transformer for encapsulated high-voltage devices which is simple and inexpensive, has a low weight, does not require a toroidal core, which has no frequency and amplitude-dependent non-linearities, and which has a safe, permanent, non-destructive operation of the Allows high-voltage device with the current transformer.
  • the specified object is achieved according to the invention by a current transformer for encapsulated high-voltage devices with the features according to patent claim 1 and/or by an encapsulated high-voltage device according to patent claim 12 .
  • Advantageous configurations of the current transformer according to the invention for encapsulated high-voltage devices and/or the encapsulated high-voltage device according to the invention are specified in the dependent claims.
  • objects of the main claim with Features of subclaims and features of the subclaims can be combined with one another.
  • a current transformer according to the invention for encapsulated high-voltage devices comprises at least one coil which is arranged around at least one current-carrying conductor, the at least one current-carrying conductor being arranged in an encapsulating housing.
  • the at least one coil is designed or in the form of an air coil without a magnetic core. is an air coil without a magnetic core.
  • An air coil without a magnetic core i . H . an air coil without a magnetic core saves a toroidal core, has a lower weight compared to a coil with a magnetic core, is simple and inexpensive, and has no frequency- and amplitude-dependent non-linearities of a coil with a toroidal core.
  • the current transformer according to the invention with the air-core coil without a magnetic core is smaller in design than with coils with a magnetic core, is lighter and cheaper to purchase, the measurement has high linearity over the entire measuring range and there are no saturation effects. Furthermore, only low electrical losses occur even with high currents and no forces act on the measuring system, i . H . the current transformer, with which a significantly simplified constructive implementation of the measuring system is connected.
  • Identical coils can be used for the entire current measurement range from a few amperes to a few hundred kiloamperes, which also represents a cost-related advantage. Further advantages result from a lower risk potential for e.g. B. Maintenance personnel dealing with the current transformer and high-voltage device, especially during installation and maintenance. This enables safe, permanent, non-destructive operation of the high-voltage device with the current transformer.
  • the air coil without a magnetic core can be used in the manner of a Rogowski
  • Rogowski coils are simple and cost- to be produced inexpensively in large quantities and have the advantages described above.
  • the at least one coil can be arranged outside of the encapsulating housing. This enables simple maintenance without opening the encapsulating housing and space in the encapsulating housing is saved, which in particular saves costs and material.
  • the at least one coil can be arranged in a holder, in particular in a groove, which can be formed in the holder.
  • the arrangement of the at least one coil in a holder, in particular in a groove, enables precise spatial and permanent positioning of the at least one coil. This enables an exact, error-free measurement of the current through the current-carrying conductor with the current transformer or the at least one coil.
  • the mount can include a cover which in particular completely covers the at least one coil. This ensures permanent protection of the at least one coil in the holder, in particular against environmental influences, e.g. B. Weather influences allowed.
  • the holder can consist of an electrically non-conductive material, in particular plastic.
  • Plastic enables magnetic fields to be measured around a current-carrying conductor with a coil without measuring errors or adulterations .
  • the at least one coil can be circular, and the at least one current-carrying conductor can be arranged in the center of the circular shape, in particular with its longitudinal axis perpendicular to the plane of the circle. Precise positioning of the coil around the current-carrying conductor, in particular constant over time in a groove, with the current-carrying conductor at the center of the circular shape of the coil, enables error-free measurement and determination of the current flowing through the current-carrying conductor.
  • the encapsulating housing can include aluminum and/or consist of aluminum.
  • Aluminum does not distort the magnetic fields of the current-carrying conductor or only slightly, which means that an error-free or Substantially error-free measurement of the current through the current-carrying conductor is made possible by the magnetic field generated around the conductor and by the current induced in the coil by the field, with a coil outside the encapsulating housing.
  • the at least one coil can consist of a sheathed electrical conductor, in particular a copper conductor, in particular with a sheath made of electrically non-conductive plastic.
  • a sheathed electrical conductor i . H . lines or . Cables are easy and inexpensive to form or form into a coil. to wrap .
  • Copper conductor coils are well suited for electrical measurements, especially induced currents.
  • the at least one coil can be wound on a carrier, in particular a carrier made of electrically non-conductive material, in particular paper, plastic and/or Teflon.
  • a carrier made of electrically non-conductive material, in particular paper, plastic and/or Teflon.
  • the winding on a carrier is inexpensive and easily possible, and the carrier provides the winding with a permanent mechanical hold. Supports made of paper, plastic and/or Teflon do not falsify the induction and measurements of currents induced in conductors. This makes them well suited for use in current transformers with coils without a magnetic core.
  • Auxiliary units in particular at least one evaluation unit, an amplifier, and/or a power supply can be included in the current transformer according to the invention, in particular arranged in a housing in the form of a box and/or a cabinet, in particular arranged on and/or near the encapsulating housing, in particular with at least one cable connection of the at least one coil to the auxiliary units.
  • the auxiliary units enable measurement using the coil and evaluation, display and/or transmission of measurement results.
  • the arrangement in a housing outside the encapsulating housing enables simple, trouble-free evaluation and reading as well as transmission of measurement results, as well as easy maintenance of the auxiliary units.
  • An encapsulated high-voltage device comprises at least one current transformer as described above, in particular arranged outside of an encapsulating housing which is designed to be gas-tight and/or is filled with a switching gas, in particular SF 6 and/or clean air.
  • a switching gas in particular SF 6 and/or clean air.
  • a high-voltage circuit breaker can be included in the encapsulated high-voltage device, which can be connected to power generators, power consumers and/or power lines of a power grid by the at least one current-carrying conductor.
  • the encapsulated high-voltage device can be in the form of a gas-insulated switchgear, in particular a dead-tank gas-insulated switchgear.
  • Figure 1 shows a schematic of an encapsulated high-voltage device 1 with a current-carrying conductor in an encapsulating housing 5, on which a current transformer 9 are arranged according to the prior art with a toroidal core with a secondary winding and a current transformer 2 according to the invention with an air-core coil without a magnetic core, and
  • FIG. 2 the current transformer 2 of FIG.
  • FIG. 3 shows the current transformer 2 from FIG. 2, with the holder 6 without a cover 8 and the coil 3 arranged in a slot 7 .
  • the high-voltage device 1 is z. B. designed as a switchgear, with a high-voltage circuit breaker inside the encapsulating housing 5 .
  • the switchgear is designed in particular as a dead-tank gas I insulated switchgear, d. H . Gas-insulated switchgear, with the high-voltage circuit breaker or the switching unit is arranged in a grounded housing.
  • the high-voltage device 1 is z. B.
  • the encapsulating housing 5 is z. B. designed in boiler form and z. B. made of aluminium .
  • Two bushings for current-carrying conductors or Connections with connection lugs for electrical power generators, consumers and/or mains lines are arranged on the encapsulating housing 5 , in particular at an oblique angle and directed upwards away from the encapsulating housing 5 .
  • the current-carrying conductors are arranged inside the bushings and are not shown in the external view of FIG.
  • the implementations are z. B. made of ceramic micro, silicone and/or a composite material.
  • the current-carrying conductors connect z. B. the high-voltage circuit breaker inside the encapsulating housing 5 electrically with the terminal lugs for the electrical power generator, consumer and / or power lines.
  • the encapsulating housing 5 is z. B. Arranged on two mechanically stable supports, in particular two leiterf örmigen metal frames, which on a foundation, z. B. made of concrete, are arranged.
  • a current transformer 9 according to the prior art, with a toroidal core with a secondary winding, is on the circumference of a bushing or arranged around a bushing, shown in FIG. 1 on the right-hand side of the encapsulating housing 5 .
  • the current transformer 9 with toroidal core and secondary winding is z. B. designed as an inductive push-through current transformer.
  • the toroidal core is made from high-quality sheet metal with high permeability and is provided with an appropriate secondary winding.
  • the toroidal core made of laminations leads to a spatially voluminous design of the current transformer 9, with a high weight, and requires a solid design with high mechanical stability in order to withstand loads caused by high currents or Magnetic fields are caused.
  • FIG. 1 A current transformer 2 according to the invention with an air coil without a magnetic core is shown in FIG. 1 on the left-hand side of the encapsulating housing 5, adjacent to the bushing on the left-hand side.
  • FIGS. 2 and 3 the arrangement of the current transformer 2 according to the invention on the encapsulating housing 5 is enlarged and shown in detail.
  • the current-carrying conductor 4 inside the bushings, which projects into the encapsulating housing 5 or. runs in the encapsulating housing 5 is shown in broken lines in FIGS.
  • the head 4 is z.
  • the conductor 4 which lugs from the terminal for electrical power generators, consumers and / or power lines for high-voltage switching device or.
  • the currents generate a magnetic field, which penetrates the encapsulating housing 5 , in particular made of aluminum, and is measured by the current transformer 2 according to the invention by inducing current in a coil 3 of the current transformer 2 without a magnetic core.
  • the current transformer 2 thus measures the current via a conductor 4 in the encapsulating housing 5 or via the switching unit. This is to ensure safe, trouble-free operation, e.g. B. the switching unit and/or connected devices as well as the network.
  • the state of the switching unit and its trouble-free function can be determined in this way and, in particular with critical currents, z. B. a shutdown will take place.
  • the encapsulating housing 5 of the high-voltage device 1 has a flange at the connection point for the passage of the conductor 4 , in particular a hollow cylindrical flange as an opening in the encapsulating housing 5 , which is shaped like a kettle.
  • the current transformer 2 according to the invention with an air coil without a magnetic core is outside, arranged in a circle around the flange.
  • the current transformer 2 has a holder 6 in which the coil 3 is arranged.
  • the holder 6 is shown with a cover 8 which covers the coil 6 and protects against environmental influences such as eg. B. Protects against moisture, UV radiation and/or other weather influences.
  • the holder 6 with the cover 8 encapsulates the coil 3 in particular completely, e.g. B. waterproof .
  • the holder 6 is shown without the cover 8 .
  • the holder 6 is ring-shaped, in particular circular in shape, and has a groove 7 , i. H . an in particular annular recess in the holder 6 .
  • the coil 6 without a magnetic core is arranged in the groove 7, in particular stored special spatially fixed.
  • the spatial fixation of the coil 3 in the holder 6 with the groove 7 enables an error-free measurement of currents in the current-carrying conductor 4 with the aid of the coil 4 .
  • the coil is stored unchanged in terms of space and time, even with large forces on the coil 3 , in particular due to magnetic fields and currents induced in the coil 3 .
  • the holder 6 and thus the coil 3 in the groove 7 of the holder 6 are arranged around the current-carrying conductor such that when the coil 3 is circular, the current-carrying conductor 4 penetrates with its longitudinal axis perpendicularly the plane of the coil 3 , in particular in the center of the circular shape the coil 3 .
  • the bracket 6 and / or the cover 8 are z.
  • B. F formed from plastic, and fasteners such.
  • the coil 3 without a magnetic core is designed in particular in the manner of a Rogowski coil.
  • the coil 3 is connected via electrical lines in particular to auxiliary units, e.g. B. connected to an evaluation unit, an amplifier, and/or a power supply, which for the sake of simplicity are not shown in the figures.
  • auxiliary units e.g. B. connected to an evaluation unit, an amplifier, and/or a power supply, which for the sake of simplicity are not shown in the figures.
  • the currents induced in the coil 3 can be measured, evaluated, displayed and/or sent to other devices, such as B. to a central control room, sense boxes, and/or decentralized handheld devices such as e.g. B. Laptops, tablets, and/or cell phones.
  • a current transformer 2 according to the invention with a coil 3 without a magnetic core, in particular with a holder 6 and cover 8, is spatially much smaller than a current transformer 9 according to the prior art with a toroidal core with a secondary winding, in particular in an associated housing , lighter in weight, and enables permanent, reliable, error-free measurement of the currents through a current-carrying conductor 4, arranged in the encapsulation housing 5, of the encapsulated high-voltage device 1 according to the invention.
  • the exemplary embodiments described above can be combined with one another and/or can be combined with the prior art.
  • classic current transformers 9 according to the prior art with a toroidal core with a secondary winding and current transformers 2 according to the invention with a coil 3 without a magnetic core, in particular a Rogowski coil can be used on an encapsulated high-voltage device 1, in particular used simultaneously .
  • the high-voltage device 1 is or includes z. a high voltage circuit breaker, isolator, arrester and/or bushing for high voltage, and/or may be used in medium voltage applications.
  • the high-voltage device 1 is z. B. designed as an outdoor switchgear and / or as a gas-insulated switchgear.
  • the execution is z. B. as a live tank, arranged with a switching unit in an isolator, such as. B. in a ribbed ceramic, silicone and / or composite material f- insulator housing, or as a dead tank, d. H. arranged with a switching unit in a grounded housing, in particular a housing in the form of a kettle.
  • the coil 3 includes z. B. a particular sheathed copper cable, and / or cables made of electrically conductive materials such. As aluminum and / or steel, or superconductors.
  • the bracket 6 and / or the cover 8 are z. B. made of plastic, and / or include ceramic, silicone and / or composite material fe.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Transformers For Measuring Instruments (AREA)

Abstract

L'invention concerne un transformateur de courant (2) pour des appareils haute tension (1) sous enveloppe et un appareil haute tension (1) sous enveloppe pourvu du transformateur de courant (2), le transformateur de courant (2) présentant au moins une bobine (3) qui est disposée autour d'au moins un conducteur (4) parcouru de courant, l'au moins un conducteur (4) parcouru de courant étant disposé dans un boîtier formant enveloppe (5) et l'au moins une bobine (3) étant une bobine à air dépourvue de noyau magnétique.
PCT/EP2021/076157 2020-09-30 2021-09-23 Appareil haute tension sous enveloppe et transformateur de courant pour l'appareil haute tension sous enveloppe WO2022069332A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102020212350.0A DE102020212350A1 (de) 2020-09-30 2020-09-30 Gekapseltes Hochspannungsgerät und Stromwandler für das gekapselte Hochspannungsgerät
DE102020212350.0 2020-09-30

Publications (1)

Publication Number Publication Date
WO2022069332A1 true WO2022069332A1 (fr) 2022-04-07

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ID=78080250

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Application Number Title Priority Date Filing Date
PCT/EP2021/076157 WO2022069332A1 (fr) 2020-09-30 2021-09-23 Appareil haute tension sous enveloppe et transformateur de courant pour l'appareil haute tension sous enveloppe

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Country Link
DE (1) DE102020212350A1 (fr)
WO (1) WO2022069332A1 (fr)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6424059B1 (en) * 1999-12-27 2002-07-23 Mitsubishi Denki Kabushiki Kaisha Gas insulated switching device
JP2002315120A (ja) * 2001-02-07 2002-10-25 Hitachi Ltd ガス絶縁開閉装置
US6850399B1 (en) * 2000-03-01 2005-02-01 Hitachi, Ltd. Gas insulated device and failure rating method
WO2009139521A1 (fr) * 2008-05-13 2009-11-19 Taehwatrans Co., Ltd. Capteur de courant de type élément de serrage avec bobine de rogowski
WO2020174522A1 (fr) * 2019-02-25 2020-09-03 日新電機株式会社 Structure d'électrode intermédiaire, transformateur l'utilisant et détecteur de décharge partielle

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH682190A5 (fr) 1991-04-22 1993-07-30 Asea Brown Boveri
EP0825447B1 (fr) 1996-08-23 2008-04-02 ABB Schweiz AG Appareil de mesure pour une installation blindée à haute tension à isolation de gaz
EP0825448A3 (fr) 1996-08-23 1999-12-29 Asea Brown Boveri AG Appareil mesure pour une installation blindée à haute tension à isolation de gaz
US6295190B1 (en) 1999-10-26 2001-09-25 Electric Boat Corporation Circuit breaker arrangement with integrated protection, control and monitoring
DE102015214043A1 (de) 2015-07-24 2016-06-02 Siemens Aktiengesellschaft Nullflussstromwandler

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6424059B1 (en) * 1999-12-27 2002-07-23 Mitsubishi Denki Kabushiki Kaisha Gas insulated switching device
US6850399B1 (en) * 2000-03-01 2005-02-01 Hitachi, Ltd. Gas insulated device and failure rating method
JP2002315120A (ja) * 2001-02-07 2002-10-25 Hitachi Ltd ガス絶縁開閉装置
WO2009139521A1 (fr) * 2008-05-13 2009-11-19 Taehwatrans Co., Ltd. Capteur de courant de type élément de serrage avec bobine de rogowski
WO2020174522A1 (fr) * 2019-02-25 2020-09-03 日新電機株式会社 Structure d'électrode intermédiaire, transformateur l'utilisant et détecteur de décharge partielle

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