CN111443323A - 30000A current transformer field mobile calibration system - Google Patents

30000A current transformer field mobile calibration system Download PDF

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Publication number
CN111443323A
CN111443323A CN202010337142.2A CN202010337142A CN111443323A CN 111443323 A CN111443323 A CN 111443323A CN 202010337142 A CN202010337142 A CN 202010337142A CN 111443323 A CN111443323 A CN 111443323A
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China
Prior art keywords
unit
current
current transformer
mobile
site
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Pending
Application number
CN202010337142.2A
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Chinese (zh)
Inventor
吴志武
王春光
黄天富
伍翔
周志森
陈江洪
曾园园
阮聿津
王璐
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Wuhan Pandian Sci Tech Co ltd
Electric Power Research Institute of State Grid Fujian Electric Power Co Ltd
State Grid Fujian Electric Power Co Ltd
Original Assignee
Wuhan Pandian Sci Tech Co ltd
Electric Power Research Institute of State Grid Fujian Electric Power Co Ltd
State Grid Fujian Electric Power Co 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.)
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Application filed by Wuhan Pandian Sci Tech Co ltd, Electric Power Research Institute of State Grid Fujian Electric Power Co Ltd, State Grid Fujian Electric Power Co Ltd filed Critical Wuhan Pandian Sci Tech Co ltd
Priority to CN202010337142.2A priority Critical patent/CN111443323A/en
Publication of CN111443323A publication Critical patent/CN111443323A/en
Pending legal-status Critical Current

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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R35/00Testing or calibrating of apparatus covered by the other groups of this subclass
    • G01R35/02Testing or calibrating of apparatus covered by the other groups of this subclass of auxiliary devices, e.g. of instrument transformers according to prescribed transformation ratio, phase angle, or wattage rating

Abstract

The invention relates to a 30000A current transformer field mobile verification system. The on-site error checking device is used for checking on-site errors of the large-current transformer and the extra-high voltage current transformer; the intelligent voltage regulation and control device comprises a mobile laboratory and an intelligent voltage regulation and control unit, a reactive compensation unit, a large-current rising unit, a standard current transformer unit, an error measurement unit and a load unit which are arranged in the mobile laboratory. The invention can be used for field calibration of the 30kA current transformer at the outlet of the generator and field test of the 1000kV extra-high voltage current transformer, and has the advantages of high integration, high intelligent degree, high test efficiency, strong reusability and the like.

Description

30000A current transformer field mobile calibration system
Technical Field
The invention belongs to the technical field of current transformer error testing, and particularly relates to a 30000A current transformer field mobile verification system.
Background
The current transformer is an electrical device which performs current proportion conversion and high-voltage isolation through an electromagnetic induction principle, and is a key element for metering, measuring and protecting a power system. The method has the advantages that the method is accurate, stable and reliable in operation, and the fairness of electric quantity trade settlement and the safety of power grid operation are related. According to the requirements of the national verification regulation JJJG 1021-2007 'power transformer', the current transformer needs to be inspected before commissioning and periodically inspected on site.
With the development of power systems, the transformation ratio of the current transformer is also larger and larger, for example, the primary current passing of the extra-high voltage current transformer is 6000A, and the primary current of the generator outlet current transformer is generally 15000A to 25000A. Taking a 25000A generator outlet current transformer as an example, if a scheme of a traditional current booster is adopted, the current is required to be boosted to 30000A, at least about 800kVA of power supply capacity and current booster capacity is required, the capacity increase of the traditional current booster and a field test power supply is relied on, the verification requirement is difficult to meet, and the current booster with large capacity has large volume, heavy weight and great field operation difficulty. For the on-site calibration of the large-current transformer, no test device is used at present, and laboratory submission is mostly adopted.
Disclosure of Invention
The invention aims to provide a 30000A current transformer field mobile calibration system, which solves the problem that the prior art can not realize the field calibration of a large current transformer at the outlet of a generator, simultaneously enables calibration equipment to be compatible with the calibration capability of extra-high voltage and below current transformers, and improves the field test efficiency and the operation safety of the current transformer.
In order to achieve the purpose, the technical scheme of the invention is as follows: A30000A current transformer field mobile calibration system is used for field error calibration of a large current transformer and an extra-high voltage current transformer; the intelligent voltage regulation and compensation system comprises a mobile laboratory, and an intelligent voltage regulation and control unit, a reactive compensation unit, a large-current boosting unit, a standard current transformer unit, an error measurement unit and a load unit which are arranged in the mobile laboratory;
the input winding and the field test power of intelligence pressure regulating control unit are connected, reactive compensation unit connects in parallel in intelligence pressure regulating control unit's output winding, intelligence pressure regulating control unit's output winding still with heavy current upwelling unit connects, heavy current upwelling unit, standard current transformer unit's primary winding and the primary winding of being surveyed current transformer constitute the heavy current return circuit that establishes ties, the secondary winding of standard current transformer unit establishes ties with the secondary winding of being surveyed current transformer, and is connected to the error measurement unit, the load unit is connected in being surveyed current transformer's secondary winding.
In an embodiment of the present invention, the intelligent voltage regulation control unit includes a main voltage regulator, an electric regulation mechanism, an auxiliary voltage regulation unit and a protection device, wherein an output terminal of the main voltage regulator is connected in series with an output terminal of the auxiliary voltage regulation unit; the auxiliary voltage regulating unit is formed by cascading a fine voltage regulator and an isolation transformer.
In an embodiment of the present invention, the reactive compensation unit is composed of a multi-combination self-healing capacitor, an electric switching device, and a protection device; the multi-group self-healing capacitor is composed of a plurality of compensation capacitors with equal rated voltages and stepwise increased compensation capacity.
In an embodiment of the present invention, the large-current boosting unit is composed of a plurality of sets of current boosters with consistent parameters; a primary winding of the current booster is led out by adopting a busbar; the high-current boosting unit realizes high-current output of 0-30000A by parallel and serial use of primary windings of a plurality of groups of current boosting devices.
In an embodiment of the invention, the large-current boosting unit realizes a 30000A large-current output mode, namely, four current boosting devices are connected in parallel in the same direction to inject current, so that the on-site calibration current boosting of a current transformer at the outlet of a generator is met; the on-site calibration current rise of the extra-high voltage current transformer can be realized by connecting the two current rises in parallel; the single current booster can realize the on-site calibration current boost of the current transformer of 500kV or below.
In an embodiment of the present invention, the standard current transformer unit is composed of a 10kA standard current transformer and a 30kA standard current transformer, and is respectively suitable for checking current transformers with respective ranges.
In one embodiment of the invention, the system also comprises a central centralized control and data exchange unit arranged in the mobile laboratory, wherein the central centralized control and data exchange unit comprises a centralized operation table board, a man-machine interaction large screen unit and a test site monitoring unit; the mobile laboratory is of a box-type structure; the centralized operation table top is arranged in the mobile laboratory box body and is used for operation of operators; the test environment monitoring unit is used for collecting the temperature and the humidity outside the mobile laboratory and displaying the temperature and the humidity through the human-computer interaction large screen unit; the test site monitoring unit comprises four outdoor high-definition cameras arranged at four top points above the mobile laboratory box body, a test alarm bell arranged on one side face of the front end of the mobile laboratory box body and four alarm lamps arranged at the top of the mobile laboratory box body.
In an embodiment of the invention, the top of the box-type structure of the mobile laboratory can be opened, so that a large-current boosting unit and a standard current transformer unit which are arranged in the mobile laboratory can be conveniently lifted out for use.
Compared with the prior art, the invention has the following beneficial effects: the 30000A current transformer field mobile verification system comprises an intelligent voltage regulation control unit, a reactive compensation unit, a large current rising unit, a standard current transformer unit, an error measurement unit, a load unit, a central centralized control and data exchange unit and a mobile laboratory, is used for field error verification of 30000A and below large current transformers, can automatically measure and record error data of tested transformers, can store and upload the measured data online, can automatically generate reports by using upper computer software, and can store and print the reports. The system can be used for field calibration of the 30kA current transformer at the outlet of the generator and field tests of extra-high voltage and below current transformers, and has the advantages of strong reusability, high integration level, high intelligent degree, high test efficiency, safer operation, more application scenes and the like.
Drawings
Fig. 1 is a diagram of a 30000A current transformer field mobile verification system according to the present invention.
Fig. 2 is a schematic diagram of the intelligent voltage regulation control unit of the present invention.
Fig. 3 is a perspective view of a mobile laboratory structure according to the present invention.
FIG. 4 is a top view of a mobile laboratory structure according to the present invention.
In the figure, 1-warning lamp, 2-loudspeaker, 3-L ED illuminating lamp, 4-top cover, 5-high-definition camera, 6-door, 7-air-conditioning box, 8-wire row, 9-electric bell, 10-10000A standard current transformer, 11-current booster, 12-door handle, 13-30000A standard current transformer and 14-intelligent voltage regulation control unit.
Detailed Description
The technical scheme of the invention is specifically explained below by combining the attached drawings 1-4.
The invention provides a 30000A current transformer field mobile verification system, which is used for field error verification of a large current transformer and an extra-high voltage current transformer; the intelligent voltage regulation and compensation system comprises a mobile laboratory, and an intelligent voltage regulation and control unit, a reactive compensation unit, a large-current boosting unit, a standard current transformer unit, an error measurement unit and a load unit which are arranged in the mobile laboratory;
the input winding and the field test power of intelligence pressure regulating control unit are connected, reactive compensation unit connects in parallel in intelligence pressure regulating control unit's output winding, intelligence pressure regulating control unit's output winding still with heavy current upwelling unit connects, heavy current upwelling unit, standard current transformer unit's primary winding and the primary winding of being surveyed current transformer constitute the heavy current return circuit that establishes ties, the secondary winding of standard current transformer unit establishes ties with the secondary winding of being surveyed current transformer, and is connected to the error measurement unit, the load unit is connected in being surveyed current transformer's secondary winding.
The following is a specific implementation of the present invention.
As shown in fig. 1, the invention provides a 30000A current transformer field mobile verification system, which is used for field error verification of a large current transformer and an extra-high voltage current transformer; the intelligent voltage regulation and compensation system comprises a mobile laboratory, and an intelligent voltage regulation and control unit, a reactive compensation unit, a large-current boosting unit, a standard current transformer unit, an error measurement unit and a load unit which are arranged in the mobile laboratory;
the input winding and the field test power of intelligence pressure regulating control unit are connected, reactive compensation unit connects in parallel in intelligence pressure regulating control unit's output winding, intelligence pressure regulating control unit's output winding still with heavy current upwelling unit connects, heavy current upwelling unit, standard current transformer unit's primary winding and the primary winding of being surveyed current transformer constitute the heavy current return circuit that establishes ties, the secondary winding of standard current transformer unit establishes ties with the secondary winding of being surveyed current transformer, and is connected to the error measurement unit, the load unit is connected in being surveyed current transformer's secondary winding.
In this example, as shown in fig. 2, the intelligent voltage regulation control unit is configured to provide input currents of different magnitudes for the large current rising unit, and includes a main voltage regulator, an electric adjusting mechanism, an auxiliary voltage regulation unit, and a protection device, where an output terminal of the main voltage regulator is connected in series with an output terminal of the auxiliary voltage regulation unit; the auxiliary voltage regulating unit is formed by cascading a fine voltage regulator and an isolation transformer and is used for realizing accurate regulation of current under 1% -5% rated current (low current).
In the example, the reactive compensation unit consists of a multi-combination self-healing capacitor, an electric switching device and a protection device; the multi-group self-healing capacitor is composed of a plurality of compensation capacitors with equal rated voltages and stepwise increased compensation capacity. The compensation capacity range is 0 kVA-1193.75 kVar, the compensation fineness is 6.25 kVar, the number of compensation gears is 191, and the maximum compensation offset is 3.125 kVar.
In this example, the large-current boosting unit consists of a plurality of groups of current boosters with consistent parameters, and the output parameters are 20V and 7500A; a primary winding (large current) of the current booster is led out by adopting a busbar; the high-current boosting unit realizes high-current output of 0-30000A by parallel and serial use of primary windings of a plurality of groups of current boosting devices.
In this example, the large-current boosting unit realizes a large-current output mode of 30000A, that is, four current boosting devices are connected in parallel in the same direction to inject current, so that on-site calibration current boosting of a current transformer at the outlet of the generator is satisfied; the on-site calibration current rise of the extra-high voltage current transformer can be realized by connecting the two current rises in parallel; the single current booster can realize the on-site calibration current boost of the current transformer of 500kV or below.
In the example, the standard current transformer unit consists of a 10kA standard current transformer and a 30kA standard current transformer, which are respectively suitable for the calibration of the current transformers in respective measuring ranges.
In the example, the system further comprises a central centralized control and data exchange unit arranged in the mobile laboratory, the central centralized control and data exchange unit comprises a centralized operation table board, a man-machine interaction large screen unit, a test site monitoring unit and an office matching device, the mobile laboratory is of a box-type structure, the centralized operation table board is arranged in a mobile laboratory box body and is used for operation of operators, the test environment monitoring unit is used for collecting temperature and humidity outside the mobile laboratory and displaying the temperature and humidity through the man-machine interaction large screen unit, the test site monitoring unit comprises four outdoor high-definition cameras arranged at four top points above the mobile laboratory box body, a test alarm bell arranged on one side face of the front end of the mobile laboratory box body and four alarm lamps arranged at the top of the mobile laboratory box body, and the office matching device comprises L ED light assistance, a top-type air conditioner, an office chair and the like.
As shown in fig. 3-4, in this example, the top of the box structure of the mobile laboratory can be opened, so that the large current rising unit and the standard current transformer unit arranged in the mobile laboratory can be conveniently lifted out for use.
The above are preferred embodiments of the present invention, and all changes made according to the technical scheme of the present invention that produce functional effects do not exceed the scope of the technical scheme of the present invention belong to the protection scope of the present invention.

Claims (8)

1. A30000A current transformer field mobile verification system is characterized in that the system is used for field error verification of a large current transformer and an extra-high voltage current transformer; the intelligent voltage regulation and compensation system comprises a mobile laboratory, and an intelligent voltage regulation and control unit, a reactive compensation unit, a large-current boosting unit, a standard current transformer unit, an error measurement unit and a load unit which are arranged in the mobile laboratory;
the input winding and the field test power of intelligence pressure regulating control unit are connected, reactive compensation unit connects in parallel in intelligence pressure regulating control unit's output winding, intelligence pressure regulating control unit's output winding still with heavy current upwelling unit connects, heavy current upwelling unit, standard current transformer unit's primary winding and the primary winding of being surveyed current transformer constitute the heavy current return circuit that establishes ties, the secondary winding of standard current transformer unit establishes ties with the secondary winding of being surveyed current transformer, and is connected to the error measurement unit, the load unit is connected in being surveyed current transformer's secondary winding.
2. The on-site mobile verification system of a 30000A current transformer according to claim 1, wherein said intelligent voltage regulation control unit comprises a main voltage regulator, an electric regulation mechanism, an auxiliary voltage regulation unit and a protection device, an output terminal of said main voltage regulator is connected in series with an output terminal of said auxiliary voltage regulation unit; the auxiliary voltage regulating unit is formed by cascading a fine voltage regulator and an isolation transformer.
3. The field mobile calibration system of 30000A current transformer according to claim 1, wherein said reactive compensation unit comprises multiple sets of self-healing capacitors, electric switching devices and protection devices; the multi-group self-healing capacitor is composed of a plurality of compensation capacitors with equal rated voltages and stepwise increased compensation capacity.
4. The field mobile verification system of a 30000A current transformer according to claim 1, wherein the high-current boosting unit comprises a plurality of sets of current boosters with consistent parameters; a primary winding of the current booster is led out by adopting a busbar; the high-current boosting unit realizes high-current output of 0-30000A by parallel and serial use of primary windings of a plurality of groups of current boosting devices.
5. The on-site mobile verification system for the 30000A current transformer according to claim 4, wherein the high-current boosting unit realizes a high-current output mode of 30000A, namely, current is injected by four current boosters in parallel in the same direction, so that on-site verification current boosting of the current transformer at the outlet of the generator is met; the on-site calibration current rise of the extra-high voltage current transformer can be realized by connecting the two current rises in parallel; the single current booster can realize the on-site calibration current boost of the current transformer of 500kV or below.
6. The on-site mobile verification system of a 30000A current transformer according to claim 1, wherein said standard current transformer unit is composed of a 10kA standard current transformer and a 30kA standard current transformer, each suitable for respective range current transformer verification.
7. The on-site mobile calibration system of a 30000A current transformer according to claim 1, further comprising a central centralized control and data exchange unit disposed in the mobile laboratory, which comprises a centralized operation table, a human-computer interaction large screen unit, and a test site monitoring unit; the mobile laboratory is of a box-type structure; the centralized operation table top is arranged in the mobile laboratory box body and is used for operation of operators; the test environment monitoring unit is used for collecting the temperature and the humidity outside the mobile laboratory and displaying the temperature and the humidity through the human-computer interaction large screen unit; the test site monitoring unit comprises four outdoor high-definition cameras arranged at four top points above the mobile laboratory box body, a test alarm bell arranged on one side face of the front end of the mobile laboratory box body and four alarm lamps arranged at the top of the mobile laboratory box body.
8. The on-site mobile verification system for 30000A current transformer, according to claim 1, wherein the top of the box structure of the mobile laboratory is openable to facilitate hanging out of the large current upwash unit and the standard current transformer unit in the mobile laboratory.
CN202010337142.2A 2020-04-26 2020-04-26 30000A current transformer field mobile calibration system Pending CN111443323A (en)

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CN202010337142.2A CN111443323A (en) 2020-04-26 2020-04-26 30000A current transformer field mobile calibration system

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113820644A (en) * 2021-09-16 2021-12-21 国网四川省电力公司营销服务中心 Distribution network mutual inductor measurement performance integrated on-site calibration device

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CN102096060A (en) * 2010-11-30 2011-06-15 国网电力科学研究院 Circuit for checking on-site accuracy of current transformer under condition of underload operations
CN102510225A (en) * 2011-10-28 2012-06-20 广东电网公司广州供电局 Method, device and experiment system for increasing output current of current rising device
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CN113820644A (en) * 2021-09-16 2021-12-21 国网四川省电力公司营销服务中心 Distribution network mutual inductor measurement performance integrated on-site calibration device

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Application publication date: 20200724