CN2689550Y - Three-phase brake for preventing transformer differential prevent from malfunction - Google Patents
Three-phase brake for preventing transformer differential prevent from malfunction Download PDFInfo
- Publication number
- CN2689550Y CN2689550Y CN 200420020110 CN200420020110U CN2689550Y CN 2689550 Y CN2689550 Y CN 2689550Y CN 200420020110 CN200420020110 CN 200420020110 CN 200420020110 U CN200420020110 U CN 200420020110U CN 2689550 Y CN2689550 Y CN 2689550Y
- Authority
- CN
- China
- Prior art keywords
- current
- differential protection
- phase
- input
- transformer
- 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
Abstract
The utility model relates to a three-phase braking device for preventing transformer differential protection from false action, which comprises a ratio braking element through using three-phase differential current in the transformer differential protection and the zero sequence current of the Y < 0 > side respectively. When the ratio value of the differential current and the zero sequence current is smaller than a set value K, the corresponding differential current is judged as error current caused by an outer area fault. A comparator outputs 0, and the signal is output by way of an or gate 4. When the or gate 4 outputs 0, a three-phase differential protection outlet is closed. Otherwise, the or gate 4 outputs 1 and permits the three-phase differential protection device to carry out action. The advantages of the project are that the utility model can completely avoid the false action of the transformer differential protection device caused by the outer area grounding fault of the Y < 0 > side when the error of three-phase current transformers is inconsistent. The utility model does not influence the correct action of the differential protection device under the condition of the inner area fault.
Description
Technical field
The utility model relates to a kind of protection equipment for transformer, particularly a kind of three-phase brake apparatus that prevents the transformer differential protection malfunction.
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 Y
0The power transformer of/Δ wiring is for preventing Y
0Lateral areas external ground fault zero-sequence current causes differential protection malfunction, extensively adopts Y at present
0The side three-phase current carries out the method for conversion, eliminates the influence of zero-sequence current.But work as Y
0Side threephase current transformer error is inconsistent, and transformer is only at the Y that external area error takes place
0When side has power supply, can not eliminate Y by conventional method
0The influence of the zero-sequence current that lateral areas external ground fault causes; bigger differential unsymmetrical current will be had; ratio brake element, the braking member that shoves can not reliably be braked this; especially very little even be under zero the situation at transformer opposite side load current; 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 utility model provides a kind of three-phase brake apparatus that prevents the transformer differential protection malfunction, by with the three-phase differential current in the transformer differential protection respectively with Y
0The zero-sequence current component ratio braking member of side, when differential current and zero-sequence current rate value during less than setting value K, declaring corresponding phase differential current is the error current that external area error causes, signal through or door output after, the outlet of locking three-phase differential protection.The utility model has the advantages that, in the time of can avoiding the threephase current transformer error inconsistent fully, Y
0The transformer differential protection malfunction that lateral areas external ground fault causes, and the correct operation of differential protection under the zone of influence internal fault situation not.
A kind of three-phase brake apparatus that prevents the transformer differential protection malfunction; this device circuit constitutes as shown in Figure 1; it is characterized in that: this device is made of filter 11～14, multiplier 2, comparator 31～33 or door 4, and the input of its median filter 11～13 is A, B, the C three-phase differential current instantaneous value signal i of the formation of input transformer differential protection respectively
Da, i
Db, i
Dc, the input input transformer Y of filter 14
0Side zero-sequence current instantaneous value signal 3i
oAn input of its output termination multiplier 2, another input input setting value K of multiplier 2, the negative input end of comparator 31～33 is connected with the output of multiplier 2, its positive input terminal connects the output of filter 11～13 respectively, the output of comparator 31～33 respectively with or door three inputs of 4 be connected or the output of door 4 output three-phase brake signal.Positive input terminal signal in comparator 31～33 is less than the negative input end signal; comparator output 0; declaring corresponding phase differential current is the error current that external area error causes; signal warp or door 4 outputs; or door 4 was exported 0 o'clock; locking rate of three phase flow differential protection outlet, otherwise or door 4 outputs 1, allow the action of three-phase differential protection.Arrive the same side in differential current and the equal reduction of zero-sequence current, under the same no-load voltage ratio situation, setting value K is 0＜K＜1/3; The characteristic of filter 11～14 should be consistent.
With prior art relatively, the utility model has the advantages that proposed first in traditional transformer differential protection, to set up with the three-phase differential current in the transformer differential protection respectively with Y
0The zero-sequence current ratio brake element of side, when rate value during less than setting value K, declaring corresponding phase differential current is the error current that external area error causes, signal through or door output, the outlet of locking rate of three phase flow differential protection.Use this programme, in the time of can avoiding the threephase current transformer error inconsistent fully, Y
0The transformer differential protection malfunction that lateral areas external ground fault 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 three-phase brake apparatus of transformer differential protection malfunction.
Embodiment
Embodiment 1:
A kind of three-phase brake apparatus that prevents the transformer differential protection malfunction, its circuit structure as shown in Figure 1, when the positive input terminal signal of comparator 31～33 less than the negative input end signal, comparator output 0, declaring corresponding phase differential current is the error current that external area error causes, signal warp or door 4 outputs, or door 4 was exported locking rate of three phase flow differential protection general export at 0 o'clock; Otherwise or door 4 exports 1, the action of permission differential protection.Arrive the same side in differential current and the equal reduction of zero-sequence current, under the same no-load voltage ratio situation, setting value K is 0.1; The advantage of this device is, in the time of can avoiding the threephase current transformer error inconsistent fully, and Y
0The transformer differential protection malfunction that lateral areas external ground fault causes, and the correct operation of differential protection under the zone of influence internal fault situation not.
Claims (3)
1. three-phase brake apparatus that prevents the transformer differential protection malfunction; it is characterized in that: this device is made of filter (11～14), multiplier (2), comparator (31～33) or door (4), and the input of its median filter (11～13) is (A, B, C) three-phase differential current instantaneous value signal (i of input transformer differential protection formation respectively
Da, i
Db, i
Dc), the input input transformer Y of filter (14)
0Side zero-sequence current instantaneous value signal (3i
o), an input of its output termination multiplier (2), another input input setting value (K) of multiplier (2), the negative input end of comparator (31～33) is connected with the output of multiplier (2), its positive input terminal connects the output of filter (11～13) respectively, the output of comparator (31～33) respectively with or three inputs of door (4) be connected or the output output three-phase brake signal of door (4).
2. device according to claim 1 is characterized in that: to the same side, under the same no-load voltage ratio situation, setting value (K) is 0＜K＜1/3 in differential current and the equal reduction of zero-sequence current.
3 devices according to claim 1 is characterized in that: the characteristic of filter (11～14) should be consistent.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200420020110 CN2689550Y (en) | 2004-02-13 | 2004-02-13 | Three-phase brake for preventing transformer differential prevent from malfunction |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200420020110 CN2689550Y (en) | 2004-02-13 | 2004-02-13 | Three-phase brake for preventing transformer differential prevent from malfunction |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2689550Y true CN2689550Y (en) | 2005-03-30 |
Family
ID=34669239
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200420020110 Expired - Fee Related CN2689550Y (en) | 2004-02-13 | 2004-02-13 | Three-phase brake for preventing transformer differential prevent from malfunction |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2689550Y (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100407534C (en) * | 2004-02-13 | 2008-07-30 | 浙江大学 | Three-phase brake device for preventing voltage transformer differential protection unwanted operation |
-
2004
- 2004-02-13 CN CN 200420020110 patent/CN2689550Y/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100407534C (en) * | 2004-02-13 | 2008-07-30 | 浙江大学 | Three-phase brake device for preventing voltage transformer differential protection unwanted operation |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN2689550Y (en) | Three-phase brake for preventing transformer differential prevent from malfunction | |
| CN2687916Y (en) | Maximum different-current brake device for preventing transformer differential protection from being malfunction | |
| CN100407534C (en) | Three-phase brake device for preventing voltage transformer differential protection unwanted operation | |
| CN2689551Y (en) | Comprehensive differential flow braker for preventing transformer differential protection from malfunction | |
| CN2689552Y (en) | Three-phase braker for preventing transformer differential protector from malfunction by fault component | |
| CN2689554Y (en) | Split-phase braker for preventing multi-branch transformer differential protector from malfunction | |
| CN2687917Y (en) | Split-phase brake device for preventing transformer differential protection from being malfunction using failure component | |
| CN2687915Y (en) | Split-phase brake device for preventing transformer differential protection from being malfunction | |
| CN2689556Y (en) | Three-phase braker for preventing multi-branch transformer differential protector from malfunction | |
| CN100350694C (en) | Integrated differential flow brake device for preventing voltage transformer differential protection unwanted operation | |
| CN100413168C (en) | Integrated differential flow method for preventing voltage transformer differential protection unwanted operation | |
| CN100350695C (en) | Integrated difference stream brake device for preventing voltage transformer differential protection unwanted operation by utilizing fault components | |
| CN2689555Y (en) | Split-phase braker for preventing multi-branch transformer differential protector from malfunction | |
| CN2689553Y (en) | Maximum differential flow braker for preventing transformer differential protector from malfunction by fault component | |
| CN2687920Y (en) | Three-phase comprehensive brakedevice for preventing multi-branch transformer differential protection from being malfunction | |
| CN2687918Y (en) | Maximum different-current brake device for preventing multi-branch tansformer differential protection from being malfunction | |
| CN100367596C (en) | Phase-splitting brake device for preventing voltage transformer differential protection unwanted operation | |
| CN2689558Y (en) | Maximum differential comprehensive braker for preventing multi-branch transformer differential protector from malfunction | |
| CN100377461C (en) | Maximum differential flow brake device for preventing voltage transformer differential protection unwanted operation | |
| CN2687919Y (en) | Positive sequence synthetic brake device for preventing multi-branch differential protection from being malfunction | |
| CN100350709C (en) | Positive and zero sequence fault component braking method for preventing transformer protection from malfunction | |
| CN2711963Y (en) | Fault component positive sequence synthetic brake for preventing transformer protection from error action | |
| CN2711969Y (en) | Fault component three-phase zero sequence brake for preventing transformer protection from error action | |
| CN100409522C (en) | Three-phase brake device for preventing voltage transformer differential protection unwanted operation by utilizing fault components | |
| CN100350705C (en) | Maximum current zero sequence braking method for preventing transformer protection malfunction |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |