CN104730408B - A kind of method for verifying high-power transformer differential circuit correctness - Google Patents
A kind of method for verifying high-power transformer differential circuit correctness Download PDFInfo
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- 238000000034 method Methods 0.000 title claims abstract description 32
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- 210000004899 c-terminal region Anatomy 0.000 claims description 3
- CUZMQPZYCDIHQL-VCTVXEGHSA-L calcium;(2s)-1-[(2s)-3-[(2r)-2-(cyclohexanecarbonylamino)propanoyl]sulfanyl-2-methylpropanoyl]pyrrolidine-2-carboxylate Chemical compound [Ca+2].N([C@H](C)C(=O)SC[C@@H](C)C(=O)N1[C@@H](CCC1)C([O-])=O)C(=O)C1CCCCC1.N([C@H](C)C(=O)SC[C@@H](C)C(=O)N1[C@@H](CCC1)C([O-])=O)C(=O)C1CCCCC1 CUZMQPZYCDIHQL-VCTVXEGHSA-L 0.000 claims description 2
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Abstract
The invention discloses a kind of method for verifying high-power transformer differential circuit correctness, the present invention is applied in the debugging test before being put into operation first to transformer, or in the checking experiment to being carried out after the stoppage in transit of transformer；After being tested according to the method for the present invention; it can be selected from test connection, current transformer (abbreviation CT) polarity; and the correctness in tri- aspect checking transformer differential loops of each side CT of transformer; inspection project is comprehensive, reliability is high; can avoid transformer put into operation after transformer differential protection do load test verification differential circuit correctness when; due to differential protection loop wiring is incorrect or CT no-load voltage ratios, polarity selection it is incorrect, cause suspend transformer carry out replacing second loop return wiring.
Description
Technical field
The invention belongs to transformer technology field, more particularly to a kind of high-power transformer differential circuit correctness that verifies
Method.
Background technology
Application number 201010211397.0, " transformer differential protection secondary connection returns application publication number CN 101907670A
Describe a kind of method for verifying correctness of transformer differential protection secondary connection loop in road method for verifying correctness ", but this
Method is only used for the inspection of 35kV and following small capacity transformer differential circuit, because high-power transformer, because experiment is set
Standby off-capacity, transformer can not be given directly once through-flow, but the secondary circuit of 110kV and above transformer is same
Sample need checked,
The content of the invention
The purpose of the embodiment of the present invention is to provide a kind of method for verifying high-power transformer differential circuit correctness, purport
Solving the problems, such as that high-power transformer can not be carried out once through-flow its differential protection loop correctness of inspection.
The embodiment of the present invention is achieved in that a kind of method for verifying high-power transformer differential circuit correctness, should
The method of verification high-power transformer differential circuit correctness includes：
Step 1: respectively by high-pressure side A phases and low-pressure side A phase short circuits before experiment, high-pressure side B phases and low-pressure side B phase short circuits,
High-pressure side C phases and low-pressure side C phase short circuits；
Step 2: a wherein end for a flow device output end to be connected on to the A phases of high voltage side of transformer, access point should be
Between breaker DL1 and transformer LH1, other end ground connection；
Step 3: being incorporated into G2 disconnecting switch, breaker DL1, disconnecting switch G1, breaker DL2 are opened；
Step 4: the voltage class of transformer high-low-voltage side is changed to same numerical value；
Step 5: being stepped up the electric current of a flow device, the secondary electricity in A phases high-pressure side in protection device is checked respectively for
Stream, A phase low-pressure side secondary currents, A phases difference current and stalling current, wherein difference current is almost 0, stalling current>>Difference
During streaming current, high voltage side current=current source institute output numerical value/high-pressure side CT no-load voltage ratios, low-pressure side electric current=current source exports number
Value/low-pressure side CT no-load voltage ratios；
Step 6: after checking out A phase currents, a flow device primary connection is moved into B phases, two-step of repeat step
Five, complete that a flow device primary connection is moved into C phases, two-step 5 of repeat step after B phases check.
Further, the current source capability of a flow device is 150VA in step 2.
Further, in step 4, the mode of connection of transformer is changed to YY connections by 220kV；By transformer high-low-voltage
The CT no-load voltage ratios of the participation differential protection of side are changed to consistent with physical cabling；
Further, if flow device of method of the verification high-power transformer differential circuit correctness is adjusted using three-phase
Depressor is then completed high-pressure side A phases and low-pressure side A phase short circuits, high-pressure side B phases and low-pressure side B phase short circuits, high-pressure side C phases with it is low
Press side C phase short circuits；After operation, three-phase regulator A, B, C-terminal are respectively connected to A, B, C phase of high voltage side of transformer, access point
Should be between breaker DL1 and transformer LH1, AN, BN, CN reliable ground of pressure regulator；Carry out being incorporated into G2 disconnecting switch afterwards,
Open breaker DL1, disconnecting switch G1, breaker DL2；The voltage class of transformer high-low-voltage side is changed to same numerical value；
The electric current of a flow device is stepped up, it is secondary to check respectively for A phases high-pressure side secondary current, A phase low-pressure sides in protection device
Electric current, A phases difference current and stalling current, wherein difference current are almost 0, stalling current>>During difference current, high-pressure side
Electric current=current source institute output numerical value/high-pressure side CT no-load voltage ratios, low-pressure side electric current=current source institute output numerical value/low-pressure side CT become
Than.
Further, if method volume three change of the verification high-power transformer differential circuit correctness, first carry out it is high, in two
Side checks, then carries out high and low both sides inspection.
The method of verification high-power transformer differential circuit correctness provided by the invention, can be used in checking various voltages
(especially high-power transformer is differential for the method for grade transformer (not including auto-transformer) differential protection loop correctness
Loop), the scope of examination includes the correctness of circuit connection, the correctness of current transformer (CT) polarity selection, each side of transformer
The correctness of CT no-load voltage ratios.The present invention is applied in the debugging test before being put into operation first to transformer, or the stoppage in transit to transformer
In the checking experiment carried out afterwards；, can be from test connection, current transformer (letter after being tested according to the method for the present invention
Claim CT) polarity selection, and the correctness in transformer differential loop is verified in terms of each side CT of transformer tri-, inspection project is complete
Face, reliability are high, can avoid transformer put into operation after transformer differential protection doing load test verification differential circuit just
During true property, due to differential protection loop wiring is incorrect or CT no-load voltage ratios, polarity selection it is incorrect, cause suspend transformer carry out
Change second loop return wiring.The present invention can carry out effective, comprehensive inspection to high-power transformer differential protection loop, simultaneously
Due to the present invention carry out it is once through-flow when, primary current not by transformer, therefore using identical capacity flow device
In the case of, resulting secondary current value is bigger so that test data influenceed by drift, harmonic wave, electromagnetic interference it is smaller,
Test data is more accurate.
Brief description of the drawings
Fig. 1 is the method flow diagram of verification high-power transformer differential circuit correctness provided in an embodiment of the present invention；
Fig. 2 is transformer primary circuit provided in an embodiment of the present invention schematic diagram.
Fig. 3 is three-winding transformer primary circuit schematic diagram provided in an embodiment of the present invention
Embodiment
In order to make the purpose , technical scheme and advantage of the present invention be clearer, with reference to embodiments, to the present invention
It is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, it is not used to
Limit the present invention.
Below in conjunction with the accompanying drawings and specific embodiment is further described to the application principle of the present invention.
As shown in figure 1, the method for the verification high-power transformer differential circuit correctness of the embodiment of the present invention is including following
Step：
S101：By high-pressure side A phases and low-pressure side A phase short circuits, high-pressure side B phases and low-pressure side B phase short circuits, high-pressure side C phases with
Low-pressure side C phase short circuits；
S102：Capacity is connected on to the A phases of high voltage side of transformer for a wherein end of flow device output end of 150VA,
Access point should be between breaker and transformer, other end reliable ground；
S103：Disconnecting switch is incorporated into, opens breaker and transformer；
S104：Change protection equipment for transformer parameter：The voltage class of transformer high-low-voltage side is changed to same numerical value；
S105：The electric current of a flow device is stepped up, checks respectively for A phases high-pressure side secondary current, A in protection device
Phase low-pressure side secondary current, A phases difference current and stalling current, wherein difference current are almost 0, stalling current>>Differential electricity
During stream, high voltage side current=current source institute output numerical value/high-pressure side CT no-load voltage ratios, low-pressure side electric current=current source institute output numerical value/
Low-pressure side CT no-load voltage ratios；
S106：After checking out A phase currents, current source primary connection is moved into B phases, repeat step S102~S105, completes B
A flow device primary connection is moved into C phases, repeat step S102~S105 after mutually checking.
The specific embodiment of the present invention：
Step 1: respectively by high-pressure side A phases and low-pressure side A phase short circuits before experiment, high-pressure side B phases and low-pressure side B phase short circuits,
High-pressure side C phases and low-pressure side C phase short circuits；
Step 2: a wherein end for flow device (current source, a capacity 150VA) output end is connected on transformer height
Press the A phases (access point should be between breaker DL1 and transformer LH1) of side, other end reliable ground；
Step 3: as shown in Fig. 2 be incorporated into G2 disconnecting switch, DL1, G1, DL2 are opened；
Step 4: change protection equipment for transformer parameter：The voltage class of transformer high-low-voltage side is changed to same number
Value, such as：220kV；The mode of connection of transformer is changed to YY connections；By the participation differential protection of transformer high-low-voltage side
CT no-load voltage ratios are changed to consistent with physical cabling；
Step 5: being stepped up the electric current of a flow device, the secondary electricity in A phases high-pressure side in protection device is checked respectively for
Stream, A phase low-pressure side secondary currents, A phases difference current and stalling current, wherein difference current is almost 0, stalling current>>Difference
During streaming current, high voltage side current=current source institute output numerical value/high-pressure side CT no-load voltage ratios, low-pressure side electric current=current source exports number
Value/low-pressure side CT no-load voltage ratios；
Step 6: after checking out A phase currents, current source primary connection is moved into B phases, two~step 5 of repeat step will
A phases in step are changed to corresponding B or C phases, complete B and want current source primary connection is moved into C phases, repeat step after checking
Two~step 5.
If if flow device uses three-phase regulator after first step operation is completed, can by three-phase regulator A, B,
C-terminal is respectively connected to A, B, C phase (access point should be between breaker DL1 and transformer LH1) of high voltage side of transformer, pressure regulator
AN, BN, CN reliable ground；Step 3-5 is carried out afterwards.
If the changes of volume three, can first carry out high, middle both sides and check, then carry out high and low both sides inspection.14 sections of of specification
With the contrast of prior art：
With application number 201010211397.0, application publication number CN 101907670A " transformer differential protection secondary connections
Method in loop method for verifying correctness " is different, and this method of calibration can verify the secondary circuit polarity of high-power transformer
Correctness, and the method for application number 201010211397.0 is when transformer capacity is very big, after primary side is through-flow, due to instrument
The limitation of capacity, two sub-values obtained in protection equipment for transformer will very little, loop correctness can not be judged, therefore
201010211397.0 method is typically only used for the differential circuit inspection of 35kV and its following small capacity transformer；The present invention
Can effectively solve the defects of this aspect, so that volume two become as an example, specific practice is as follows：First, respectively by high-pressure side A before testing
Phase and low-pressure side A phase short circuits, high-pressure side B phases and low-pressure side B phase short circuits, high-pressure side C phases and low-pressure side C phase short circuits；2nd, will once
A wherein end of flow device (general capacity is 2000VA) output end is connected on the A phases of high voltage side of transformer, and (access point should be disconnected
Between road device DL1 and transformer LH1), other end reliable ground；3rd, as shown in figure 3, being incorporated into G2 disconnecting switch, opening DL1,
G1、DL2；4th, protection equipment for transformer parameter is changed：The voltage class of transformer high-low-voltage side is changed to same numerical value, such as：
220kV；The mode of connection of transformer is changed to YY connections；By the CT no-load voltage ratios of the participation differential protection of transformer high-low-voltage side
It is changed to consistent with physical cabling；5th, the electric current of a flow device is stepped up, checks respectively for A phases high pressure in protection device
Side secondary current, A phase low-pressure side secondary currents, A phases difference current and stalling current, wherein difference current is almost 0, braking
Electric current>>During difference current, high voltage side current=current source institute output numerical value/high-pressure side CT no-load voltage ratios, low-pressure side electric current=current source
Institute's output numerical value/low-pressure side CT no-load voltage ratios；6th, after checking out A phase currents, current source primary connection is moved into B phases, repeat step
Two-five, complete B and want current source primary connection is moved into C phases, repeat step two-five after checking.
It is correct instant invention overcomes in the past through-flow its differential protection loop of inspection can not be carried out once to high-power transformer
Property the shortcomings that so that high-power transformer can also be comprehensive to check current circuit connections just by once through-flow method
True property, the correctness of current transformer (abbreviation CT) polarity selection, the correctness of each side CT no-load voltage ratios of transformer.
The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all essences in the present invention
All any modification, equivalent and improvement made within refreshing and principle etc., should be included in the scope of the protection.
Claims (5)
- A kind of 1. method for verifying high-power transformer differential circuit correctness, it is characterised in that the verification high-power transformer The method of differential circuit correctness includes：It is Step 1: respectively that high voltage side of transformer A phases and low-pressure side A phase short circuits, high-pressure side B phases and low-pressure side B phases is short before experiment Connect, high-pressure side C phases and low-pressure side C phase short circuits；Step 2: a wherein end for a flow device output end to be connected on to the A phases of high voltage side of transformer, access point should be in open circuit Between device DL1 and transformer LH1, other end ground connection；Step 3: being incorporated into G2 disconnecting switch, breaker DL1, disconnecting switch G1, breaker DL2 are opened；Step 4: the voltage class of transformer high-low-voltage side is changed to same numerical value；Step 5: being stepped up the electric current of a flow device, A phases high-pressure side secondary current, A phases in protection device are checked respectively for Low-pressure side secondary current, A phases difference current and stalling current, wherein difference current are almost 0, stalling current>>Difference current When, high voltage side current=current source institute output numerical value/high-pressure side CT no-load voltage ratios, low-pressure side electric current=current source institute output numerical value/low Press side CT no-load voltage ratios；Step 6: after checking out A phase currents, a flow device primary connection is moved into B phases, two~step 5 of repeat step, A phases in step are changed to corresponding B or C phases, a flow device primary connection is moved into C after completion B phases-inspection Phase, two~step 5 of repeat step.
- 2. the method for verification high-power transformer differential circuit correctness as claimed in claim 1, it is characterised in that in step The current source capability of a flow device is 150VA in two.
- 3. the method for verification high-power transformer differential circuit correctness as claimed in claim 1, it is characterised in that in step In four, the mode of connection of transformer is changed to YY connections by 220kV；By the CT of the participation differential protection of transformer high-low-voltage side No-load voltage ratio is changed to consistent with physical cabling.
- 4. the method for verification high-power transformer differential circuit correctness as claimed in claim 1, it is characterised in that the verification The method of high-power transformer differential circuit correctness is completed high-pressure side A if a flow device uses three-phase regulator Phase and low-pressure side A phase short circuits, high-pressure side B phases and low-pressure side B phase short circuits, high-pressure side C phases and low-pressure side C phase short circuits；, will after operation Three-phase regulator A, B, C-terminal are respectively connected to A, B, C phase of high voltage side of transformer, and access point should be in breaker DL1 and transformer Between LH1, AN, BN, CN reliable ground of pressure regulator；Carry out being incorporated into G2 disconnecting switch afterwards, open breaker DL1, keep apart Close G1, breaker DL2；The voltage class of transformer high-low-voltage side is changed to same numerical value；It is stepped up a flow device Electric current, check respectively for A phases high-pressure side secondary current in protection device, A phase low-pressure side secondary currents, A phases difference current and Stalling current, wherein difference current are almost 0, stalling current>>During difference current, high voltage side current=current source exports number Value/high-pressure side CT no-load voltage ratios, low-pressure side electric current=current source institute output numerical value/low-pressure side CT no-load voltage ratios.
- 5. the method for verification high-power transformer differential circuit correctness as claimed in claim 1, it is characterised in that the verification If the changes of volume three of the method for high-power transformer differential circuit correctness, if the changes of volume three, carry out the inspection of height both sides first： DL3, G3 are disconnected, the polarity of high and low pressure side is checked；The polarity check of senior middle school both sides is carried out afterwards：DL2, G2 are disconnected, DL2, G2 are changed to DL3, and G3 is that the polarity of high pressure side is checked.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| EP3236553A1 (en) | 2016-04-20 | 2017-10-25 | Siemens Aktiengesellschaft | Method and device for detecting phase failures, in particular grid defects, in a converter |
| CN109406907B (en) * | 2018-12-09 | 2021-03-02 | 国网辽宁省电力有限公司锦州供电公司 | High-impedance transformer simulation loaded through-flow test device and test method |
| CN110596512A (en) * | 2019-09-04 | 2019-12-20 | 广州粤能电力科技开发有限公司 | Large-scale transformer differential protection polarity verification method and device and computer equipment |
| CN111624523A (en) * | 2020-06-02 | 2020-09-04 | 西安热工研究院有限公司 | System and method for verifying differential protection polarity of line of generator-transformer unit wiring mode system |
| CN113567891B (en) * | 2021-08-05 | 2023-11-17 | 中石化第十建设有限公司 | Transformer differential system test method and test device |
| CN117169640B (en) * | 2023-11-02 | 2024-02-20 | 云南电力试验研究院(集团)有限公司 | Multiple ratio differential verification method and device under multi-distributed new energy access feeder line |
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