CN115754877A - Device and method for diagnosing electromagnetic PT faults through no-load characteristic test - Google Patents

Device and method for diagnosing electromagnetic PT faults through no-load characteristic test Download PDF

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Publication number
CN115754877A
CN115754877A CN202211429696.0A CN202211429696A CN115754877A CN 115754877 A CN115754877 A CN 115754877A CN 202211429696 A CN202211429696 A CN 202211429696A CN 115754877 A CN115754877 A CN 115754877A
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electromagnetic
voltage
voltage transformer
alternating current
fault
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龙翱翔
吴定亮
刘康康
代康为
石磊
杨杨
田莎
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Guizhou Power Grid Co Ltd
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Guizhou Power Grid Co Ltd
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    • Y—GENERAL 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
    • Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
    • Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
    • Y04S10/00—Systems supporting electrical power generation, transmission or distribution
    • Y04S10/50—Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
    • Y04S10/52—Outage or fault management, e.g. fault detection or location

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Abstract

The invention discloses an electromagnetic PT fault diagnosis device and method for no-load characteristic test, which comprises an AC comprehensive control box and an AC voltage divider, wherein a terminal of the AC comprehensive control box is connected to a corresponding terminal of a secondary winding of an electromagnetic voltage transformer through a test wire, the head end of the primary winding of the electromagnetic voltage transformer is connected to the high-voltage end of the AC voltage divider through the test wire, and the low-voltage end of the AC voltage divider is connected to a monitoring display through a special test wire. The invention not only realizes simple and clear wiring, convenient and fast operation and accurate analysis and diagnosis, but also reduces the labor intensity and improves the working efficiency; the convenience in various electromagnetic point transformer tests is greatly improved, the time and the labor are saved, the working efficiency is effectively improved, the working and power failure time is saved, and the safety risk is reduced; it is worth to be widely popularized and applied in the power industry.

Description

Device and method for diagnosing electromagnetic PT fault through no-load characteristic test
Technical Field
The invention belongs to the technical field of PT fault detection, and particularly relates to a device and a method for diagnosing electromagnetic PT faults through a no-load characteristic test.
Background
The failure property and reason analysis of the electromagnetic voltage transformer cannot be correctly judged in daily tests, and although the electromagnetic voltage transformer has a plurality of test items, the failure and winding hidden danger of an iron core are difficult to accurately judge, for example: insulation resistance detection can only reflect whether the whole body is affected with damp or aged or not, and the existence of partial defects can not react; the direct current resistance detection can only reflect broken wires and short circuits, the secondary winding of the electromagnetic transformer is thick, the primary winding of the electromagnetic transformer is too thin, the measurement result is not intuitive and has larger error, the judgment is not easy, the applied voltage of the transformation ratio test is lower, the inter-turn fault condition of the winding cannot be reflected, and the alternating current withstand voltage is difficult to implement for the electromagnetic voltage transformer with graded insulation.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the device and the method for diagnosing the electromagnetic PT fault through the no-load characteristic test are provided, and the technical problems in the prior art are solved.
The technical scheme adopted by the invention is as follows: a no-load characteristic test diagnosis electromagnetic PT fault device comprises an alternating current comprehensive control box, an alternating current voltage divider, a flow comprehensive control box and the alternating current voltage divider, wherein a terminal of the alternating current comprehensive control box is connected to a corresponding terminal of a secondary winding of an electromagnetic voltage transformer through a test wire, the head end of the primary winding of the electromagnetic voltage transformer is connected to the high-voltage end of the alternating current voltage divider through the test wire, and the low-voltage end of the alternating current voltage divider is connected to a monitoring display through a special test wire.
A method for diagnosing an electromagnetic PT fault device by a no-load characteristic test comprises the following steps: the method comprises the following steps that an alternating current comprehensive control box and an alternating current voltage divider are adopted for corresponding wiring, namely, a terminal corresponding to a secondary winding of the electromagnetic voltage transformer is connected to a terminal corresponding to the alternating current comprehensive control box through a test wire, the head end of the primary winding of the electromagnetic voltage transformer is connected to the high-voltage end of the alternating current voltage divider through the test wire, the low-voltage end of the alternating current voltage divider is connected to a monitoring display through a special test wire, and after wiring, for wiring modes of different types of the electromagnetic voltage transformer, test wiring is connected to a terminal corresponding to the secondary winding of the electromagnetic voltage transformer according to the same method for detection; the electromagnetic voltage transformer is connected to the high-voltage end of the alternating-current voltage divider at one time, the low-voltage end monitors and displays readings, and fault diagnosis is carried out according to the displayed readings.
The fault diagnosis method comprises the following steps: whether the winding is in a primary side fault or a secondary side fault is judged according to the current size and the change (when the current is 0, the primary fault is judged, when the current is infinity, the secondary fault is judged), whether the winding has turn-to-turn or interlayer short circuit fault is judged according to the voltage (when the primary side phase voltage is less than 6.7kV, the turn-to-turn short circuit fault is judged, and when the primary side line voltage is less than 10kV, the interlayer short circuit fault is judged).
The electromagnetic voltage transformer comprises a dry voltage transformer, a pouring voltage transformer, an oil immersed voltage transformer or a gas voltage transformer; the detection can be carried out by adopting the same method for different wiring modes.
For the V-shaped wiring diagnosis test of the electromagnetic voltage transformer, the alternating current comprehensive control box is connected to the a end and the n end of the secondary winding of the electromagnetic voltage transformer, the high-voltage end of the alternating current voltage divider is connected to the head end of the primary winding of the electromagnetic voltage transformer, and 100V voltage is applied.
For the VV type wiring diagnosis test of the electromagnetic voltage transformer, an alternating current integrated control box is connected to a first group of a ends and n ends of a secondary winding of the electromagnetic voltage transformer, a high-voltage end of an alternating current voltage divider is connected to the head end of the primary winding of the electromagnetic voltage transformer, after the first group of a ends and n ends are tested, the second group of a ends and n ends are tested, and the two groups of tests are applied with 100V voltage.
For YY type wiring diagnosis test of the electromagnetic type voltage transformer, an alternating current comprehensive control box is connected to a first group of a ends and an n end of a secondary winding of the electromagnetic type voltage transformer, a high-voltage end of an alternating current voltage divider is connected to the head end of a primary winding of the electromagnetic type voltage transformer, after the first group of a ends and the n end are tested, tests of a second group of a ends and an n end and tests of a third group of a ends and an n end are sequentially carried out, and voltages 57.7, 57.7V and 100V are respectively applied in the three groups of tests.
For YY delta type wiring diagnosis test of the electromagnetic voltage transformer, an alternating current comprehensive control box is connected to a first group of a end and an n end of a secondary winding of the electromagnetic voltage transformer, a high-voltage end of an alternating current voltage divider is connected to the head end of the primary winding of the electromagnetic voltage transformer, after the first group of a end and the n end are tested, tests of a second group of b end and n end, a third group of c end and n end and a fourth group of a1 end and n end are sequentially carried out, and voltages 57.7, 57.7V and 100V are respectively applied to the four groups of tests.
The invention has the beneficial effects that: compared with the prior art, the invention adopts the no-load characteristic test method to judge the application of the electromagnetic PT fault, and has the advantages of simple and clear wiring, convenient and quick operation, potential safety hazard elimination, labor intensity reduction, work efficiency improvement and accurate diagnosis and analysis.
The device has simple wiring and small number of used test wires; connect convenient, swift high-efficient, the disconnect is convenient, and it is quick to change, can prevent to cause the secondary winding short circuit, has improved fail safe nature, and primary winding wiring is single, owing to can adopt the resistant high voltage insulation test wire of double-shielded, not limited by the space, carries out the prison detection under the various environment of adaptation.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a wiring diagram of the V-wiring diagnostic test circuit of the present invention;
FIG. 3 is a wiring diagram of a VV type wiring diagnostic test circuit of the present invention;
FIG. 4 is a wiring diagram of the YY wiring diagnostic test circuit of the present invention;
FIG. 5 is a wiring diagram of the YY delta wiring diagnostic test circuit of the present invention.
Detailed Description
The invention is further described below with reference to specific examples.
Example 1: as shown in fig. 1 to 5, the electromagnetic PT fault diagnosis device for no-load characteristic test includes an ac comprehensive control box, an ac voltage divider, a flow comprehensive control box, and an ac voltage divider, wherein a terminal of the ac comprehensive control box is connected to a terminal corresponding to a secondary winding of the electromagnetic voltage transformer through a test line, a head end of the primary winding of the electromagnetic voltage transformer is connected to a high-voltage end of the ac voltage divider through the test line, and a low-voltage end of the ac voltage divider is connected to a monitor display through a dedicated test line.
The structure principle of the transformer is similar to that of an oil-immersed voltage transformer or a dry voltage transformer, the transformer is realized by winding a primary winding W1 and a secondary winding W2 which are mutually insulated on an iron core of a closed magnetic loop, and the insulation strength of the transformer is approximately the same as that of the transformer with the same voltage class.
According to the regulation and the standard requirement: the test work mainly aims at finding and eliminating hidden dangers and defects, aims at recovering equipment performance and prolonging equipment service life, adheres to the principle of 'test should be performed and complete test should be performed', and adheres to the actual fact to practically solve the problems encountered in the work; simple and easy to remove the original complex form and return to true original form.
Example 2: since the voltage transformer is used to measure the electric quantity in the high-voltage ac circuit, the voltage transformer is usually used to transform the high voltage into the low voltage in the power system, and an appropriate meter is provided to measure the required parameters by using the variable relation of the voltage transformer, and the voltage transformer is also an indispensable device in the relay protection, automatic control, signal indication, etc. of the power system, the following detailed description will be made on the specific implementation scheme one by one.
The structure principle of the electromagnetic voltage transformer, whether it is an oil-immersed voltage transformer or a dry voltage transformer, is similar to that of a transformer, and the electromagnetic voltage transformer is realized by winding a primary winding W1 and a secondary winding W2 which are insulated from each other on an iron core of a closed magnetic loop, and the insulation strength of the electromagnetic voltage transformer is approximately the same as that of a transformer with the same voltage class.
According to the characteristic of the electromagnetic voltage transformer, in order to achieve the purposes of simple and clear wiring, convenient and quick operation, potential safety hazard elimination, labor intensity reduction and working efficiency improvement, the diagnosis method of the electromagnetic PT fault device by the no-load characteristic test is provided, and comprises the following steps: the method comprises the following steps that an alternating current comprehensive control box and an alternating current voltage divider are adopted for corresponding wiring, namely, a terminal corresponding to a secondary winding of the electromagnetic voltage transformer is connected to a terminal corresponding to the alternating current comprehensive control box through a test wire, the head end of the primary winding of the electromagnetic voltage transformer is connected to the high-voltage end of the alternating current voltage divider through the test wire, the low-voltage end of the alternating current voltage divider is connected to a monitoring display through a special test wire, and after wiring, for wiring modes of different types of the electromagnetic voltage transformer, test wiring is connected to a terminal corresponding to the secondary winding of the electromagnetic voltage transformer according to the same method for detection; the electromagnetic voltage transformer is connected to the high-voltage end of the alternating-current voltage divider at one time, the low-voltage end monitors and displays readings, and fault diagnosis is carried out according to the displayed readings.
The method not only realizes simple and clear wiring, convenient and fast operation and accurate analysis and diagnosis, but also achieves the purposes of reducing labor intensity and improving working efficiency.
Specific connections are shown in the following table.
Figure BDA0003944409820000051
The electromagnetic voltage transformer comprises a dry voltage transformer, a pouring voltage transformer, an oil-immersed voltage transformer or a gas voltage transformer; the detection can be carried out by adopting the same method for different wiring modes.
For the V-type wiring diagnostic test of the electromagnetic voltage transformer, as shown in fig. 2, the ac integrated control box is connected to the a end and the n end of the secondary winding of the electromagnetic voltage transformer, and the high voltage end of the ac voltage divider is connected to the head end of the primary winding of the electromagnetic voltage transformer, and applies 100V voltage.
For the VV type wiring diagnosis test of the electromagnetic voltage transformer, as shown in fig. 3, the ac integrated control box is connected to a first group of a ends and n ends of a secondary winding of the electromagnetic voltage transformer, a high voltage end of the ac voltage divider is connected to a head end of a primary winding of the electromagnetic voltage transformer, after the first group of a ends and n ends are tested, a second group of a ends and n ends are tested, and 100V is applied to both the two groups of tests.
For YY type wiring diagnosis test of the electromagnetic voltage transformer, as shown in fig. 4, the ac integrated control box is connected to a first group of a ends and n ends of a secondary winding of the electromagnetic voltage transformer, a high voltage end of the ac voltage divider is connected to a head end of the primary winding of the electromagnetic voltage transformer, after the first group of a ends and n ends are tested, tests of a second group of a ends and n ends and a third group of a ends and n ends are sequentially performed, and the three groups of tests apply voltages of 57.7, 57.7V and 100V, respectively.
For YY Δ type wiring diagnosis test of the electromagnetic voltage transformer, as shown in fig. 5, the ac integrated control box is connected to a first group of a ends and n ends of a secondary winding of the electromagnetic voltage transformer, a high voltage end of the ac voltage divider is connected to a head end of a primary winding of the electromagnetic voltage transformer, after the first group of a ends and n ends are tested, tests of a second group of b ends and n ends, a third group of c ends and n ends, and a fourth group of a1 ends and n ends are sequentially performed, wherein the four groups of tests apply voltages of 57.7, 57.7V, and 100V, respectively.
The invention has the following effects:
economic benefits are as follows: by adopting the method for diagnosing the electromagnetic PT fault by the no-load characteristic test, the test time can be saved by 0.2 hour on average each time, the average load of at least four lines of 10kV and above of each transformer substation is 25000kW, the annual economic benefit calculation method is as follows according to the zero selling price of electricity sold in the current market, and the method comprises the following steps of: the annual economic benefit = blackout times × number of lines × blackout time saved per time × load lost per time × electricity rate =26 times × 4 × 0.2 hour × 25000kW × 0.45 units/degree =23.40 ten thousand units.
Safety benefits are as follows: by adopting the scheme of the invention, the corresponding terminal of the secondary winding of the electromagnetic voltage transformer is connected to the corresponding terminal of the AC integrated control box by using the test wire, the head end of the primary winding of the electromagnetic voltage transformer is connected to the high-voltage end of the AC voltage divider by using the test wire, and the low-voltage end of the AC voltage divider is connected to the monitoring display by using the special test wire. Therefore, the method not only realizes simple and clear wiring, convenient and quick operation and accurate analysis and diagnosis, but also reduces the labor intensity and improves the working efficiency; the convenience in various electromagnetic point transformer tests is greatly improved, time and labor are saved, the working efficiency is effectively improved, the working time and the power failure time are saved, and the safety risk is reduced; it is worth to be widely popularized and applied in the power industry.
Social benefits are as follows: the method for diagnosing the electromagnetic PT fault through the no-load characteristic test can be used for accurately, quickly and reliably supplying power to power systems of 35kV or below. For a single-bus running transformer substation, the power failure time of users (residents and factories and mines) can be directly and effectively reduced, and the inconvenience and economic loss brought to the society due to power failure are reduced; the power supply risk of a power grid is effectively reduced, and the safe and reliable power utilization of the society is guaranteed; and moreover, a good social image that power supply enterprises actively undertake social responsibility is established.
The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and therefore, the scope of the present invention should be subject to the protection scope of the claims.

Claims (8)

1. The utility model provides a no-load characteristic test diagnosis electromagnetic type PT fault device which characterized in that: the terminal of the alternating current comprehensive control box is connected to a corresponding terminal of a secondary winding of the electromagnetic voltage transformer through a test wire, the head end of the primary winding of the electromagnetic voltage transformer is connected to the high-voltage end of the alternating current voltage divider through the test wire, and the low-voltage end of the alternating current voltage divider is connected to a monitoring display through a special test wire.
2. The diagnostic method for an electromagnetic PT fault diagnostic device according to claim 1, characterized in that: the method comprises the following steps: the method comprises the following steps that an alternating current comprehensive control box and an alternating current voltage divider are adopted for corresponding wiring, namely, a terminal corresponding to a secondary winding of the electromagnetic voltage transformer is connected to a terminal corresponding to the alternating current comprehensive control box through a test wire, the head end of the primary winding of the electromagnetic voltage transformer is connected to the high-voltage end of the alternating current voltage divider through the test wire, the low-voltage end of the alternating current voltage divider is connected to a monitoring display through a special test wire, and after wiring, for wiring modes of different types of the electromagnetic voltage transformer, test wiring is connected to a terminal corresponding to the secondary winding of the electromagnetic voltage transformer according to the same method for detection; the electromagnetic voltage transformer is connected to the high-voltage end of the alternating-current voltage divider at one time, the low-voltage end monitors and displays readings, and fault diagnosis is carried out according to the displayed readings.
3. The diagnosis method of an electromagnetic PT fault diagnosis apparatus for no-load characteristic test according to claim 2, characterized in that: the fault diagnosis method comprises the following steps: judging whether the winding is a primary side fault or a secondary side fault according to the current size and the change, namely judging that the primary side fault exists when the current is 0; when the current is infinity, determining that the secondary side is in fault; and judging whether the winding has turn-to-turn or interlayer short circuit faults or not according to the voltage, namely judging that the winding has the turn-to-turn short circuit faults when the primary side phase voltage is less than 6.7kV, and judging that the interlayer short circuit faults exist when the primary side line voltage is less than 10 kV.
4. The diagnosis method of an electromagnetic PT fault diagnosis apparatus for no-load characteristic test according to claim 1, characterized in that: the electromagnetic voltage transformer comprises a dry voltage transformer, a pouring voltage transformer, an oil-immersed voltage transformer or a gas voltage transformer; the detection can be carried out by adopting the same method for different wiring modes.
5. The diagnostic method for an electromagnetic PT fault diagnostic device according to claim 4, characterized in that: for the V-shaped wiring diagnosis test of the electromagnetic voltage transformer, the alternating current comprehensive control box is connected to the a end and the n end of the secondary winding of the electromagnetic voltage transformer, the high-voltage end of the alternating current voltage divider is connected to the head end of the primary winding of the electromagnetic voltage transformer, and 100V voltage is applied.
6. The diagnostic method for an electromagnetic PT fault diagnostic device according to claim 4, characterized in that: for the VV type wiring diagnosis test of the electromagnetic voltage transformer, an alternating current integrated control box is connected to a first group of a ends and n ends of a secondary winding of the electromagnetic voltage transformer, a high-voltage end of an alternating current voltage divider is connected to the head end of the primary winding of the electromagnetic voltage transformer, after the first group of a ends and n ends are tested, the second group of a ends and n ends are tested, and the two groups of tests are applied with 100V voltage.
7. The diagnostic method for an electromagnetic PT fault diagnostic device according to claim 4, characterized in that: for YY type wiring diagnosis test of the electromagnetic type voltage transformer, an alternating current comprehensive control box is connected to a first group of a ends and an n end of a secondary winding of the electromagnetic type voltage transformer, a high-voltage end of an alternating current voltage divider is connected to the head end of a primary winding of the electromagnetic type voltage transformer, after the first group of a ends and the n end are tested, tests of a second group of a ends and an n end and tests of a third group of a ends and an n end are sequentially carried out, and voltages 57.7, 57.7V and 100V are respectively applied in the three groups of tests.
8. The diagnostic method for an electromagnetic PT fault diagnostic device according to claim 4, characterized in that: for YY delta type wiring diagnosis test of the electromagnetic voltage transformer, an alternating current comprehensive control box is connected to a first group of a ends and n ends of a secondary winding of the electromagnetic voltage transformer, a high-voltage end of an alternating current voltage divider is connected to the head end of the primary winding of the electromagnetic voltage transformer, after the first group of a ends and n ends are tested, tests of a second group of b ends and n ends, a third group of c ends and n ends and a fourth group of a1 ends and n ends are sequentially carried out, and the four groups of tests respectively apply voltages of 57.7, 57.7V and 100V.
CN202211429696.0A 2022-11-15 2022-11-15 Device and method for diagnosing electromagnetic PT faults through no-load characteristic test Pending CN115754877A (en)

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