CN100407535C - Maximum difference stream brake device for preventing multiple-branch voltage transformer differential protection unwanted operation by utilizing fault components - Google Patents
Maximum difference stream brake device for preventing multiple-branch voltage transformer differential protection unwanted operation by utilizing fault components Download PDFInfo
- Publication number
- CN100407535C CN100407535C CN2004100162977A CN200410016297A CN100407535C CN 100407535 C CN100407535 C CN 100407535C CN 2004100162977 A CN2004100162977 A CN 2004100162977A CN 200410016297 A CN200410016297 A CN 200410016297A CN 100407535 C CN100407535 C CN 100407535C
- Authority
- CN
- China
- Prior art keywords
- output
- differential protection
- input
- comparator
- subtracter
- Prior art date
- Legal status (The legal status 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 status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Emergency Protection Circuit Devices (AREA)
Abstract
The present invention relates to a maximum differential stream braking device for preventing the unwanted operation of differential protection for multiple-branch transformers by utilizing fault components; a ratio braking element is composed of a maximum value in the abrupt quantities of a three-phase electric current in differential protection for transformers and a weighted sum value of the abrupt quantities of a zero-sequence electric current at each neutral point grounding side (or branch) of a transformer. When a signal at the positive input end of a comparator 9 is weaker than a signal at the negative end, the comparator 9 outputs 0; an external grounding fault is judged; a three-phase differential protection outlet is locked; or the comparator 9 outputs 1; three-phase differential protection is allowed to act. The proposal has the advantages that the present invention can thoroughly avoid the unwanted operation of differential protection for transformers caused by the external grounding fault at the neutral point grounding side when the errors of a three-phase electric current transformer are not consistent, and has no influence on the correct action of differential protection for internal faults.
Description
Technical field
The present invention relates to a kind of protection equipment for transformer, particularly a kind of maximum fault component difference stream brake apparatus that prevents malfunction for tranformer protection.
Background technology
Existing power transformer differential protection device by the ratio brake element, promptly by the ratio of differential current and through current, is discerned external area error and troubles inside the sample space; By shoving and the overexcitation braking member, promptly, discern magnetizing inrush current and overexcitation electric current simultaneously, reach the purpose of differentiating internal fault by analyzing the waveform or the harmonic content of differential current.To both sides being arranged or being the power transformer of neutral-point solid ground more than the both sides, when a ground connection side generating region external ground fault, may big earth fault zero-sequence current appear many sides.For preventing that this zero-sequence current from causing differential protection malfunction, extensively adopt the method that ground connection side three-phase current is carried out conversion at present, eliminate the influence of zero-sequence current.But it is inconsistent to work as ground connection side threephase current transformer error; and transformer is only when the neutral ground side that external area error takes place has power supply; can not eliminate the influence of the zero-sequence current that external ground fault in neutral ground lateral areas causes by conventional method; bigger differential unsymmetrical current will be had; the ratio brake element; the braking member that shoves can not reliably be braked this; especially very little even be under zero the situation at the transformer load electric current; the ratio brake element; the braking member that shoves can not be braked this; as long as error current surpasses threshold, transformer differential protection is with malfunction.
Summary of the invention
The purpose of this invention is to provide a kind of maximum fault component difference stream brake apparatus that prevents malfunction for tranformer protection; the maximum component ratio braking member of the maximum by the three-phase differential current sudden change amount in the transformer differential protection and the zero-sequence current sudden change amount of each neutral ground side of transformer or branch; when rate value during less than setting value K; be judged to district's external ground fault, the outlet of locking three-phase differential protection.Advantage of the present invention is, in the time of can avoiding the threephase current transformer error inconsistent fully, and the transformer differential protection malfunction that external ground fault in neutral ground lateral areas causes.
A kind of maximum fault component difference stream brake apparatus that prevents malfunction for tranformer protection, this device circuit constitutes as shown in Figure 1.It is characterized in that: this device by first memory 11～13, first subtracter 21～23, first filter 31～33, the first maximizing circuit 4, second memory 51,52 ... 5n, second subtracter 61,62 ... 6n, second filter 71,72 ... 7n, the second maximizing circuit 81, multiplier 82, comparator 9 constitute, wherein the three-phase differential current instantaneous value signal i of the positive input terminal of the input of first memory 11～13 and first subtracter 21～23 difference input transformer differential protection formation
Da, i
Db, i
DcThe negative input end of first subtracter 21～23 connects the output of first memory 11～13 respectively, its output is connected with the input of first filter 31～33 respectively, three inputs of the first maximizing circuit 4 connect the output of first filter 31～33 respectively, the positive input terminal of its output termination comparator 9; Second memory 51,52 ... the input of 5n and second subtracter 61,62 ... positive input terminal difference each the neutral ground side of input transformer of 6n or the zero-sequence current instantaneous value signal 3i of branch
10, 3i
203i
N0Second subtracter 61,62 ... the negative input end of 6n connect respectively second memory 51,52 ... the output of 5n, its output respectively with second filter 71,72 ... the input of 7n is connected, the input of the second maximizing circuit 81 connect respectively second filter 71,72 ... the output of 7n, an input of its output and multiplier 82 joins, another input input setting value K of multiplier 82, the negative input end of its output termination comparator 9, comparator 9 output three-phase brake signals.Arrive under the same side, the same no-load voltage ratio situation in differential current and zero-sequence current reduction, setting value K is 0＜K＜1/3.N is transformer neutral point ground connection side number or branches.When the signal of comparator 9 positive input terminals less than the negative input end signal, comparator 9 outputs 0 are judged to district's external ground fault, locking three-phase differential protection outlet, otherwise comparator 9 outputs 1 allow the action of three-phase differential protection.
With prior art relatively; advantage of the present invention be propose first in traditional transformer differential protection, to set up a kind of by the three-phase differential current sudden change amount in the transformer differential protection maximum and the maximum component ratio braking member of the zero-sequence current sudden change amount of each neutral ground side of transformer or branch; when rate value during less than setting value K; be judged to district's external ground fault, the outlet of locking three-phase differential protection.Use this programme; in the time of can avoiding the threephase current transformer error inconsistent fully; the transformer differential protection malfunction that external ground fault in neutral ground lateral areas causes; also can prevent under other non-internal fault situations; the transformer differential protection misoperation that the differential unsymmetrical current that zero-sequence current causes causes, and the correct operation of differential protection under the zone of influence internal fault situation not.
Description of drawings
Fig. 1 is the circuit block diagram that prevents the maximum fault component difference stream brake apparatus of malfunction for tranformer protection.
Embodiment
A kind of maximum fault component difference stream brake apparatus that prevents malfunction for tranformer protection, its circuit constitutes as shown in Figure 1, and transformer neutral point ground connection side is counted n=3.When the signal of comparator 9 positive input terminals during less than the negative input end signal, comparator 9 outputs 0 are judged to district's external ground fault, the outlet of locking three-phase differential protection; Otherwise comparator 9 outputs 1 allow the action of three-phase differential protection.When differential current and zero-sequence current reduction under the same side, same no-load voltage ratio situation, setting value K gets 0.2.The advantage of this device is, in the time of can avoiding the threephase current transformer error inconsistent fully, and the transformer differential protection malfunction that external ground fault in neutral ground lateral areas causes, and the correct operation of differential protection under the zone of influence internal fault situation not.
Claims (2)
1. a maximum fault component difference that prevents malfunction for tranformer protection flows brake apparatus; it is characterized in that: this device is by first memory (11～13); first subtracter (21～23); first filter (31～33); the first maximizing circuit (4); second memory (51; 52; 5n); second subtracter (61; 62; 6n); second filter (71; 72; 7n); the second maximizing circuit (81); multiplier (82); comparator (9) constitutes, wherein the three-phase differential current instantaneous value signal (i of the positive input terminal of the input of first memory (11～13) and first subtracter (21～23) difference input transformer differential protection formation
Da, i
Db, i
Dc), the negative input end of first subtracter (21～23) connects the output of first memory (11～13) respectively, its output is connected with the input of first filter (31～33) respectively, three inputs of the first maximizing circuit (4) connect the output of first filter (31～33) respectively, the positive input terminal of its output termination comparator (9), second memory (51,52 ... input 5n) and second subtracter (61,62 ... positive input terminal difference each the neutral ground side of input transformer 6n) or the zero-sequence current instantaneous value signal (3i of branch
10, 3i
20... 3i
N0); second subtracter (61; 62; negative input end 6n) connects second memory (51 respectively; 52; output 5n); its output respectively with second filter (71; 72; input 7n) is connected; the input of the second maximizing circuit (81) connects second filter (71 respectively; 72; output 7n); an input of its output and multiplier (82) joins; another input input setting value K of multiplier (82); the negative input end of its output termination comparator (9); comparator (9) output three-phase brake signal; when the signal of comparator (9) positive input terminal less than the negative input end signal; comparator (9) output 0; the outlet of locking three-phase differential protection, otherwise, comparator (9) output 1; allow the action of three-phase differential protection, n is transformer neutral point ground connection side number or branches.
2. brake apparatus according to claim 1 is characterized in that: under the same side, same no-load voltage ratio situation, setting value K is 0＜K＜1/3 in differential current and zero-sequence current reduction.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2004100162977A CN100407535C (en) | 2004-02-13 | 2004-02-13 | Maximum difference stream brake device for preventing multiple-branch voltage transformer differential protection unwanted operation by utilizing fault components |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2004100162977A CN100407535C (en) | 2004-02-13 | 2004-02-13 | Maximum difference stream brake device for preventing multiple-branch voltage transformer differential protection unwanted operation by utilizing fault components |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1558503A CN1558503A (en) | 2004-12-29 |
| CN100407535C true CN100407535C (en) | 2008-07-30 |
Family
ID=34351811
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2004100162977A Expired - Fee Related CN100407535C (en) | 2004-02-13 | 2004-02-13 | Maximum difference stream brake device for preventing multiple-branch voltage transformer differential protection unwanted operation by utilizing fault components |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100407535C (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0686447A (en) * | 1992-08-28 | 1994-03-25 | Mitsubishi Electric Corp | Grounding-transformer protective relay device |
| JPH10257667A (en) * | 1997-03-07 | 1998-09-25 | Mitsubishi Electric Corp | Power system protector |
| CN2315574Y (en) * | 1997-12-23 | 1999-04-21 | 浙江大学 | Device for discriminating fault direction of transmission line |
-
2004
- 2004-02-13 CN CN2004100162977A patent/CN100407535C/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0686447A (en) * | 1992-08-28 | 1994-03-25 | Mitsubishi Electric Corp | Grounding-transformer protective relay device |
| JPH10257667A (en) * | 1997-03-07 | 1998-09-25 | Mitsubishi Electric Corp | Power system protector |
| CN2315574Y (en) * | 1997-12-23 | 1999-04-21 | 浙江大学 | Device for discriminating fault direction of transmission line |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1558503A (en) | 2004-12-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100407535C (en) | Maximum difference stream brake device for preventing multiple-branch voltage transformer differential protection unwanted operation by utilizing fault components | |
| CN100392933C (en) | Negative sequence synthesized integrated brake device for preventing multiple-branch voltage transformer differential protection unwanted operation by utilizing fault components | |
| CN100367597C (en) | Maximum differential flow brake device for preventing multiple-branch voltage transformer differential protection unwanted operation | |
| CN100433487C (en) | Phase-splitting integrated brake device for preventing multiple-branch voltage transformer differential protection unwanted operation | |
| CN100350699C (en) | Negative sequence synthesized brake device for preventing multiple-branch voltage transformer differential protection unwanted operation by utilizing fault components | |
| CN100367598C (en) | Positive sequence synthesized brake device for preventing multiple-branch voltage transformer differential protection unwanted operation | |
| CN100409524C (en) | Three-phase brake device for preventing multiple-branch voltage transformer differential protection unwanted operation by utilizing fault components | |
| CN100413167C (en) | Maximum difference stream integrated brake device for preventing multiple-branch voltage transformer differential protection unwanted operation by utilizing fault components | |
| CN100350698C (en) | Positive sequence synthesized brake device for preventing multiple-branch voltage transformer differential protection unwanted operation by utilizing fault components | |
| CN100413169C (en) | Phase-splitting zero-sequence brake method for preventing multiple-branch voltage transformer differential protection unwanted operation | |
| CN100409526C (en) | Phase-splitting integrated brake device for preventing multiple-branch voltage transformer differential protection unwanted operation by utilizing fault components | |
| CN100409525C (en) | Three-phase integrated brake device for preventing multiple-branch voltage transformer differential protection unwanted operation by utilizing fault components | |
| CN100394657C (en) | Phase-splitting brake device for preventing multiple-branch voltage transformer differential protection unwanted operation | |
| CN100367600C (en) | Phase-splitting integrated zero-sequence brake method for preventing multiple-branch voltage transformer differential protection unwanted operation | |
| CN100413165C (en) | Phase-splitting brake device for preventing voltage transformer differential protection unwanted operation by utilizing fault components | |
| CN100413166C (en) | Maximum differential flow integrated brake device for preventing multiple-branch voltage transformer differential protection unwanted operation | |
| CN100409527C (en) | Phase sequence synthesizing method for preventing multiple-branch voltage transformer differential protection unwanted operation | |
| CN2711962Y (en) | Maximum fault component difference stream brake for preventing transformer protection from error action | |
| CN100407536C (en) | Phase sequence synthesized brake method for preventing multiple-branch voltage transformer differential protection unwanted operation by utilizing fault components | |
| CN100350697C (en) | Negative sequence differential flow integrated brake device for preventing multiple-branch voltage transformer differential protection unwanted operation | |
| CN100433488C (en) | Phase-sequence synthetic brake method for preventing multi-branch transformer differentical protection malfunction | |
| CN2711968Y (en) | Positive fault component difference stream comprehensive brake for preventing transformer protection from error action | |
| CN100350703C (en) | Phase-splitting integrated zero-sequence method for preventing voltage transformer differential protection unwanted operation by utilizing fault components | |
| CN100350696C (en) | Negative sequence synthesized brake device for preventing multiple-branch voltage transformer differential protection unwanted operation | |
| CN2711963Y (en) | Fault component positive sequence synthetic brake for preventing transformer protection from error action |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20080730 Termination date: 20110213 |