CN114256813A - CT broken line rapid locking method and system based on brake current and zero sequence current - Google Patents
CT broken line rapid locking method and system based on brake current and zero sequence current Download PDFInfo
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/22—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for distribution gear, e.g. bus-bar systems; for switching devices
- H02H7/226—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for distribution gear, e.g. bus-bar systems; for switching devices for wires or cables, e.g. heating wires
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/26—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured
- H02H7/261—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured involving signal transmission between at least two stations
- H02H7/262—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured involving signal transmission between at least two stations involving transmissions of switching or blocking orders
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Abstract
The invention discloses a CT broken line rapid locking method and system based on brake current and zero sequence current in the technical field of bus differential protection. The method comprises the following steps: sampling values according to the current of each branch of the bus; outputting a first comparison result according to the larger difference braking current value and the floating threshold value; comparing the sum of K times of the maximum value of the zero sequence mutation value of each branch of the bus and the absolute value of the zero sequence mutation value of each branch, and outputting a second comparison result; according to a preset criterion, judging that bus single-phase CT disconnection occurs, and locking the phase bus differential protection; the problem of mistakenly locking the bus differential protection under the conditions that the braking current CT disconnection criterion is subjected to single-phase high-resistance fault in a zone under the condition of partial heavy load, metal fault outside a bus zone occurs firstly, and the same-name-phase high-resistance fault in a bus zone is converted later is solved; meanwhile, the problem of mistakenly locking bus differential protection under the conditions of loop shunting, three-phase impedance imbalance and the like of the zero-sequence current CT disconnection criterion in a three-half connection mode is solved.
Description
Technical Field
The invention belongs to the technical field of bus differential protection, and particularly relates to a CT (current transformer) broken line rapid locking method and system based on braking current and zero sequence current.
Background
The bus differential protection completes analog quantity acquisition by means of a Current Transformer (CT) and a secondary circuit thereof, and if the current transformer is disconnected due to abnormality on the secondary circuit, the bus protection can generate differential current, so that bus protection misoperation is easily caused. Bus mis-tripping will cause power loss of the whole station, and seriously threatens the stability of the power system.
Both CT disconnection and internal fault generate differential flow, and protection needs to judge whether CT disconnection or internal fault occurs in a short time. The current CT disconnection criterion based on the braking current and the zero sequence current does not fully consider the influence of the conditions of single-phase high-resistance fault in a generating region, metallic fault outside a bus region and same-name phase high-resistance fault in a later-turning bus region on the CT disconnection criterion based on the braking current under the heavy load condition; and the influence of primary system loop shunting, three-phase impedance imbalance and the like on CT disconnection criterion for comparing the magnitude of the difference current and the magnitude of the branch zero-sequence current in a three-half connection mode.
Under the conditions of single-phase high-resistance fault in a generating area under the condition of partial heavy load, metal fault outside a bus area, same-name-phase high-resistance fault in a post-rotation bus area and the like, the bus braking current can drop, so that the criterion for judging CT disconnection by means of braking current rising can fail.
For bus protection of three-second connection, because of primary system loop shunting and three-phase impedance imbalance, a certain level of steady zero-sequence current exists during normal operation, and therefore the CT disconnection criterion of comparing the bus differential current value with the zero-sequence steady current value of each branch circuit fails.
Disclosure of Invention
In order to solve the defects in the prior art, the invention provides a CT broken line rapid locking method and system based on braking current and zero sequence current, and solves the technical problem of bus differential protection misoperation under the condition of partial heavy load and a three-half connection mode.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
in a first aspect, a CT wire breakage fast locking method is provided, including: acquiring current sampling values of all branches of a bus; calculating a large-difference brake current value according to the current sampling value of each branch of the bus; calculating a floating threshold value; comparing the current large-difference braking current value with a floating threshold value, and outputting a first comparison result; acquiring zero sequence mutation values of all branches of the bus except the interconnection branch; outputting the maximum value of the zero sequence mutation values of all the branches of the bus except the interconnection branch as a first calculated value; calculating the sum of absolute values of zero sequence mutation values of all the branches of the bus except the connecting branch to serve as a second calculated value; comparing the second calculated value with the K times of the first calculated value, and outputting a second comparison result; and taking the first comparison result and the second comparison result as the input of a preset criterion, and judging that the bus single-phase CT disconnection occurs when the preset criterion is met, and locking the phase bus differential protection.
Further, the preset criterion specifically includes: if the first comparison result satisfies: the large difference brake current value is smaller than the floating threshold value; meanwhile, the second comparison result satisfies: the second calculated value is smaller than the first calculated value multiplied by K, and meanwhile, the multiphase starting of the bus differential protection is not met; meanwhile, the bus large difference current multi-phase exceeding CT disconnection locking constant value is not satisfied; meanwhile, only a certain phase large difference stream is larger than the CT disconnection locking constant value; judging that the phase CT is broken and locking the phase bus differential protection; otherwise, the bus differential protection of the phase is opened.
Further, the value range of K is: k is more than 1 and less than 2.
Further, the large difference current is the vector sum of the currents of all the branches on the bus.
Further, the calculating the floating threshold value specifically includes: if the current interrupt large-difference braking current value is larger than the previous interrupt floating threshold value, the current interrupt floating threshold value is equal to the difference value between the large-difference braking current value plus A times of the large-difference braking current value and the previous interrupt floating threshold value; and if the current interrupted large difference braking current value is smaller than the previous interrupted floating threshold value, the current interrupted floating threshold value is equal to the difference value between the large difference braking current value obtained by subtracting the large difference braking current value by B times and the previous interrupted floating threshold value.
Further, the value range of A satisfies: a is more than 0 and less than 0.3.
Further, the value range of B satisfies: b is more than 0.1 and less than 1.
In a second aspect, a CT wire breakage fast locking system is provided, which includes: the first data acquisition module is used for acquiring current sampling values of all branches of the bus; the first data processing module is used for calculating a large-difference brake current value according to the current sampling value of each branch of the bus; the second data processing module is used for calculating a floating threshold value; the first comparison module is used for comparing the current large-difference braking current value with a floating threshold value and outputting a first comparison result; the second data acquisition module is used for acquiring zero sequence mutation values of all branches of the bus except the contact branch; the third data processing module is used for outputting the maximum value of the zero sequence mutation values of all the branches of the bus except the communication branch as a first calculated value; the fourth data processing module is used for calculating the sum of absolute values of zero sequence mutation values of all branches of the bus except the communication branch to serve as a second calculated value; the second comparison module is used for comparing the second calculation value with the K times of the first calculation value and outputting a second comparison result; and the judging module is used for taking the first comparison result and the second comparison result as the input of a preset criterion, judging that the bus single-phase CT disconnection occurs when the preset criterion is met, and locking the phase bus differential protection.
Compared with the prior art, the invention has the following beneficial effects: the method comprises the steps of acquiring the current value of each branch of a bus, obtaining the large-difference braking current value and calculating the floating threshold value; obtaining the maximum value and the sum of the absolute values of the zero sequence mutation values of all the branches of the bus except the connecting branch, judging that the bus single-phase CT disconnection occurs according to a preset criterion, and locking the phase bus differential protection; the problem of mistakenly locking the bus differential protection under the conditions that the braking current CT disconnection criterion is subjected to single-phase high-resistance fault in a zone under the condition of partial heavy load, metal fault outside a bus zone occurs firstly, and the same-name-phase high-resistance fault in a bus zone is converted later is solved; meanwhile, the problem of mistakenly locking bus differential protection under the conditions of loop shunting, three-phase impedance imbalance and the like of the zero-sequence current CT disconnection criterion in a three-half connection mode is solved.
Drawings
Fig. 1 is a schematic diagram of single-phase CT open-circuit bus protection fast locking criteria of a CT open-circuit fast locking method based on braking current and zero-sequence current provided by an embodiment of the present invention, (wherein, (a) is an a-phase single-phase CT open-circuit bus protection fast locking criteria, (B) is a B-phase single-phase CT open-circuit bus protection fast locking criteria, and (C) is a C-phase single-phase CT open-circuit bus protection fast locking criteria).
Detailed Description
The invention is further described below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.
The first embodiment is as follows:
a CT broken wire rapid locking method based on brake current and zero sequence current comprises the following steps: acquiring current sampling values of all branches of a bus; calculating a large-difference brake current value according to the current sampling value of each branch of the bus; calculating a floating threshold value; comparing the current large-difference braking current value with a floating threshold value, and outputting a first comparison result; acquiring zero sequence mutation values of all branches of the bus except the interconnection branch; outputting the maximum value of the zero sequence mutation values of all the branches of the bus except the interconnection branch as a first calculated value; calculating the sum of absolute values of zero sequence mutation values of all the branches of the bus except the connecting branch to serve as a second calculated value; comparing the second calculated value with the K times of the first calculated value, and outputting a second comparison result; and taking the first comparison result and the second comparison result as the input of a preset criterion, and judging that the bus single-phase CT disconnection occurs when the preset criterion is met, and locking the phase bus differential protection.
The specific steps of this example are as follows:
1) alternating current sampling: obtaining current sampling values of all branches of the bus;
2) calculating the large difference braking current: the sum of the absolute values of the currents of all the branches on the bus;
3) calculating the current floating threshold value:
if the current interrupted large difference braking current value is larger than the previous interrupted floating threshold value, the current interrupted floating threshold value is equal to the large difference braking current value plus the difference value of A times of the large difference braking current and the previous interrupted floating threshold value, and the value range of A meets the following requirements: a is more than 0 and less than 0.3; if the current interrupt large-difference braking current value is smaller than the previous interrupt floating threshold value, the current interrupt floating threshold value is equal to the difference value between the large-difference braking current value reduced by B times and the previous interrupt floating threshold value, and the value range of B meets the following requirements: b is more than 0.1 and less than 1;
4) comparing the current interrupted large-difference braking current value with a floating threshold value, and outputting a first comparison result;
5) acquiring zero sequence mutation values of all branches (except for a connecting branch) of the bus; each branch circuit self-produces the amplitude difference of the current cycle and the previous cycle of the zero sequence current;
6) finding the maximum value of the zero sequence break variable in each branch of the bus, and outputting the maximum value as a first calculated value;
7) calculating the sum of the absolute values of the zero sequence mutation values of all the branches (except the connecting branch) of the bus as a second calculated value;
8) and comparing the second calculated value with the first calculated value multiplied by K, namely comparing the magnitude of the sum of the absolute values of the zero sequence mutation of all the branches (except the connecting branch) of the bus with the magnitude of the K multiplied value of the maximum value of the zero sequence mutation in each branch (except the connecting branch) of the bus, wherein the value range of K is as follows: k is more than 1 and less than 2; outputting a second comparison result;
9) calculating a large difference flow: the vector sum of the currents of all the branches on the bus;
10) taking the first comparison result and the second comparison result as the input of a preset criterion, and when the preset criterion is met, determining that the bus single-phase CT disconnection occurs, and locking the phase bus differential protection, as shown in fig. 1, the preset criterion is specifically:
if the first comparison result satisfies: the large difference brake current value is smaller than the floating threshold value; at the same time, the user can select the desired position,
the second comparison result satisfies: the second calculated value is less than the K times the first calculated value, and at the same time,
the bus differential protection is not satisfied, and the multi-phase starting is carried out; at the same time, the user can select the desired position,
the condition that the bus large difference flow multiphase exceeds the CT disconnection locking constant value is not met; at the same time, the user can select the desired position,
only one phase large difference flow is larger than the CT disconnection locking constant value;
judging that the phase CT is broken and locking the phase bus differential protection; otherwise, the bus differential protection of the phase is opened.
The present embodiment uses a brake current floating threshold, and the brake current at the present moment is no longer compared with the brake current at the previous moment, but is compared with the floating threshold. When the braking current is reduced, the floating threshold is rapidly reduced along with the braking current, and when the braking current is increased, the floating threshold is slowly increased along with the braking current.
When the large fault outside the area is converted into the small fault inside the area, the braking current is increased, the floating threshold is raised with the raising speed, and when the large fault outside the area is converted into the small fault inside the area, the braking is reduced, the floating threshold is changed slowly, and the size of the floating threshold is almost the same as that before the fault occurs, and the braking current after the fault occurs is compared with the floating threshold to judge that the braking current is lowered.
When a single-phase CT of a single branch of a bus is disconnected, the branch current and the large-difference brake current necessarily contain zero-sequence components, and the zero-sequence component change of the brake current is completely concentrated in the disconnected branch. When an asymmetric fault occurs in a bus area, except the condition of the fault in a single-power-supply no-load bus area, the change of the zero-sequence component is distributed on each branch of the bus and cannot be concentrated on a certain branch. Based on the principle, the bus single-phase CT disconnection and the internal fault can be distinguished.
The criterion must use zero sequence current variance instead of zero sequence steady state. This is because for the bus protection of three-half wiring, because of the primary system loop shunt and the unbalanced three-phase impedance, there is a certain level of steady-state zero-sequence current in normal operation. The interference of the factor can be eliminated by adopting the zero sequence variable quantity current.
According to the CT broken line criterion and the zero sequence current distribution criterion based on the brake current floating threshold, bus differential protection does not meet the conditions that multiphase starting is not met, bus large-difference differential flow does not meet the conditions that multiphase exceeds a CT broken line locking fixed value, only one phase large-difference differential flow is larger than the CT broken line locking fixed value and the like, bus protection can be locked quickly when CT broken lines occur, and bus protection cannot be locked mistakenly when faults occur in a bus area. The logic diagram is shown in figure 1.
When the brake current criterion is met, the zero sequence current criterion is met, the bus differential protection multiphase start is not met, the bus large-difference differential flow multiphase exceeds the CT disconnection locking constant value, and only one phase large-difference differential flow is greater than the CT disconnection locking constant value, the phase is judged to be CT disconnection, and the phase bus differential protection is locked; otherwise, opening the bus differential protection of the phase; the problem of mistakenly locking the bus differential protection under the conditions that the braking current CT disconnection criterion is subjected to single-phase high-resistance fault in a zone under the condition of partial heavy load, metal fault outside a bus zone occurs firstly, and the same-name-phase high-resistance fault in a bus zone is converted later is solved; meanwhile, the problem of mistakenly locking bus differential protection under the conditions of loop shunting, three-phase impedance imbalance and the like of the zero-sequence current CT disconnection criterion in a three-half connection mode is solved.
Example two:
based on the first embodiment, a method for quickly locking a CT broken line based on a brake current and a zero sequence current is provided, and the present embodiment provides a system for quickly locking a CT broken line based on a brake current and a zero sequence current, including:
the first data acquisition module is used for acquiring current sampling values of all branches of the bus;
the first data processing module is used for calculating a large-difference brake current value according to the current sampling value of each branch of the bus;
the second data processing module is used for calculating a floating threshold value;
the first comparison module is used for comparing the current large-difference braking current value with a floating threshold value and outputting a first comparison result;
the second data acquisition module is used for acquiring zero sequence mutation values of all branches of the bus except the contact branch;
the third data processing module is used for outputting the maximum value of the zero sequence mutation values of all the branches of the bus except the communication branch as a first calculated value;
the fourth data processing module is used for calculating the sum of absolute values of zero sequence mutation values of all branches of the bus except the communication branch to serve as a second calculated value;
the second comparison module is used for comparing the second calculation value with the K times of the first calculation value and outputting a second comparison result;
and the judging module is used for taking the first comparison result and the second comparison result as the input of a preset criterion, judging that the bus single-phase CT disconnection occurs when the preset criterion is met, and locking the phase bus differential protection.
As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
Claims (8)
1. A CT broken wire rapid locking method is characterized by comprising the following steps:
acquiring current sampling values of all branches of a bus;
calculating a large-difference brake current value according to the current sampling value of each branch of the bus;
calculating a floating threshold value;
comparing the current large-difference braking current value with a floating threshold value, and outputting a first comparison result;
acquiring zero sequence mutation values of all branches of the bus except the interconnection branch;
outputting the maximum value of the zero sequence mutation values of all the branches of the bus except the interconnection branch as a first calculated value;
calculating the sum of absolute values of zero sequence mutation values of all the branches of the bus except the connecting branch to serve as a second calculated value;
comparing the second calculated value with the K times of the first calculated value, and outputting a second comparison result;
and taking the first comparison result and the second comparison result as the input of a preset criterion, and judging that the bus single-phase CT disconnection occurs when the preset criterion is met, and locking the phase bus differential protection.
2. The CT broken wire rapid locking method as claimed in claim 1, wherein the preset criterion is specifically:
if the first comparison result satisfies: the large difference brake current value is smaller than the floating threshold value; at the same time, the user can select the desired position,
the second comparison result satisfies: the second calculated value is less than the K times the first calculated value, and at the same time,
the bus differential protection is not satisfied, and the multi-phase starting is carried out; at the same time, the user can select the desired position,
the condition that the bus large difference flow multiphase exceeds the CT disconnection locking constant value is not met; at the same time, the user can select the desired position,
only one phase large difference flow is larger than the CT disconnection locking constant value;
judging that the phase CT is broken and locking the phase bus differential protection; otherwise, the bus differential protection of the phase is opened.
3. The CT broken line rapid locking method according to claim 1 or 2, wherein the value range of K is as follows: k is more than 1 and less than 2.
4. The CT wire breakage fast locking method as claimed in claim 2, wherein the large difference current is the vector sum of the currents of all the branches on the bus.
5. The CT wire break fast latching method according to claim 1, wherein the calculating of the floating threshold value specifically comprises:
if the current interrupt large-difference braking current value is larger than the previous interrupt floating threshold value, the current interrupt floating threshold value is equal to the difference value between the large-difference braking current value plus A times of the large-difference braking current value and the previous interrupt floating threshold value;
and if the current interrupted large difference braking current value is smaller than the previous interrupted floating threshold value, the current interrupted floating threshold value is equal to the difference value between the large difference braking current value obtained by subtracting the large difference braking current value by B times and the previous interrupted floating threshold value.
6. The CT broken wire rapid locking method according to claim 5, wherein the value range of A satisfies the following conditions: a is more than 0 and less than 0.3.
7. The CT broken wire rapid locking method according to claim 5, wherein the value range of B satisfies the following conditions: b is more than 0.1 and less than 1.
8. A CT broken wire quick locking system is characterized by comprising:
the first data acquisition module is used for acquiring current sampling values of all branches of the bus;
the first data processing module is used for calculating a large-difference brake current value according to the current sampling value of each branch of the bus;
the second data processing module is used for calculating a floating threshold value;
the first comparison module is used for comparing the current large-difference braking current value with a floating threshold value and outputting a first comparison result;
the second data acquisition module is used for acquiring zero sequence mutation values of all branches of the bus except the contact branch;
the third data processing module is used for outputting the maximum value of the zero sequence mutation values of all the branches of the bus except the communication branch as a first calculated value;
the fourth data processing module is used for calculating the sum of absolute values of zero sequence mutation values of all branches of the bus except the communication branch to serve as a second calculated value;
the second comparison module is used for comparing the second calculation value with the K times of the first calculation value and outputting a second comparison result;
and the judging module is used for taking the first comparison result and the second comparison result as the input of a preset criterion, judging that the bus single-phase CT disconnection occurs when the preset criterion is met, and locking the phase bus differential protection.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115173373A (en) * | 2022-09-08 | 2022-10-11 | 江苏金智科技股份有限公司 | Bus protection CT (computed tomography) broken line judgment method and device |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005039956A (en) * | 2003-07-17 | 2005-02-10 | Tm T & D Kk | Protective relay device |
| CN101162255A (en) * | 2007-11-16 | 2008-04-16 | 国电南瑞科技股份有限公司 | Method for testing CT yarn cutting through estimating out-of-balance current variation |
| CN102004208A (en) * | 2011-01-05 | 2011-04-06 | 国电南京自动化股份有限公司 | Method for rapidly distinguishing CT wire break in bus protection |
| US20140307758A1 (en) * | 2011-11-25 | 2014-10-16 | Kabushiki Kaisha Toshiba | Transmission line protective relay device |
| US20160061873A1 (en) * | 2014-08-29 | 2016-03-03 | Shanghai Jiao Tong University | Method for locating distribution network circuit fault based on full waveform information |
| CN107069673A (en) * | 2017-03-30 | 2017-08-18 | 南京南瑞继保电气有限公司 | A kind of method of quick identification branch road CT broken strings and locking bus differential protection |
| US20200335967A1 (en) * | 2017-12-20 | 2020-10-22 | Abb Power Grids Switzerland Ag | New Zero Sequence Current Based Line Differential Protection Solution |
| US20200363479A1 (en) * | 2018-02-11 | 2020-11-19 | Nr Electric Co., Ltd. | Method for detecting open phase of startup/standby transformer based on optical ct |
| CN112636309A (en) * | 2020-11-11 | 2021-04-09 | 许继电气股份有限公司 | Bus tie and branch CT disconnection detection method for direct-current power distribution network bus protection |
-
2021
- 2021-11-22 CN CN202111384852.1A patent/CN114256813B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005039956A (en) * | 2003-07-17 | 2005-02-10 | Tm T & D Kk | Protective relay device |
| CN101162255A (en) * | 2007-11-16 | 2008-04-16 | 国电南瑞科技股份有限公司 | Method for testing CT yarn cutting through estimating out-of-balance current variation |
| CN102004208A (en) * | 2011-01-05 | 2011-04-06 | 国电南京自动化股份有限公司 | Method for rapidly distinguishing CT wire break in bus protection |
| US20140307758A1 (en) * | 2011-11-25 | 2014-10-16 | Kabushiki Kaisha Toshiba | Transmission line protective relay device |
| US20160061873A1 (en) * | 2014-08-29 | 2016-03-03 | Shanghai Jiao Tong University | Method for locating distribution network circuit fault based on full waveform information |
| CN107069673A (en) * | 2017-03-30 | 2017-08-18 | 南京南瑞继保电气有限公司 | A kind of method of quick identification branch road CT broken strings and locking bus differential protection |
| US20200335967A1 (en) * | 2017-12-20 | 2020-10-22 | Abb Power Grids Switzerland Ag | New Zero Sequence Current Based Line Differential Protection Solution |
| US20200363479A1 (en) * | 2018-02-11 | 2020-11-19 | Nr Electric Co., Ltd. | Method for detecting open phase of startup/standby transformer based on optical ct |
| CN112636309A (en) * | 2020-11-11 | 2021-04-09 | 许继电气股份有限公司 | Bus tie and branch CT disconnection detection method for direct-current power distribution network bus protection |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN115173373A (en) * | 2022-09-08 | 2022-10-11 | 江苏金智科技股份有限公司 | Bus protection CT (computed tomography) broken line judgment method and device |
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