CN113541110A - Three-phase inconsistent protection method, device and system for circuit breaker - Google Patents
Three-phase inconsistent protection method, device and system for circuit breaker Download PDFInfo
- Publication number
- CN113541110A CN113541110A CN202110775189.1A CN202110775189A CN113541110A CN 113541110 A CN113541110 A CN 113541110A CN 202110775189 A CN202110775189 A CN 202110775189A CN 113541110 A CN113541110 A CN 113541110A
- Authority
- CN
- China
- Prior art keywords
- point position
- phase
- current
- position information
- double
- 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.)
- Pending
Links
Images
Classifications
-
- 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
- H02H7/263—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 measured values
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
-
- 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
- H02H7/222—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 switches
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Emergency Protection Circuit Devices (AREA)
Abstract
The application relates to a three-phase inconsistent protection method, a three-phase inconsistent protection device and a three-phase inconsistent protection system for a circuit breaker, wherein the method comprises the steps of obtaining current and double-point position information of each phase of the circuit breaker; judging whether the double-point position information is abnormal or not; when the double-point position information is abnormal, calibrating the double-point position information according to the double-point position information and the change condition of the corresponding phase current to obtain double-point position correction information; generating a control instruction according to the double-point position correction information; the control instruction is used for instructing the relay to execute three-phase inconsistent protection actions. According to the three-phase inconsistency protection method for the relay, when the two-point position information is abnormal, the abnormal position is corrected according to the two-point position information and the change condition of the corresponding phase current, the two-point position correction information can be obtained, and the control instruction is generated according to the two-point position correction information, so that the control reliability of three-phase inconsistency protection is improved.
Description
Technical Field
The application relates to the technical field of power system protection, in particular to a method, a device and a system for three-phase inconsistent protection of a circuit breaker.
Background
It is well known that in power systems, phase-split operated circuit breakers are commonly employed as switching devices. Due to various reasons such as a mechanism or an electrical operation loop, an abnormal condition that three-phase positions of the circuit breakers are inconsistent may occur, so that a power system has large zero sequence and negative sequence components, and the normal operation of the power system is seriously damaged. Therefore, it is necessary to configure a three-phase inconsistent protection function of the circuit breaker to ensure the normal operation of the power system.
According to the traditional three-phase inconsistent protection method for the circuit breaker, an auxiliary switch of the circuit breaker is connected in series and in parallel to start a time relay, and an outlet relay is started to trip in a delayed mode. However, in actual operation, due to poor operation conditions of a time relay, an outlet relay, a cable and the like adopted by three-phase inconsistent protection, conditions such as abnormal insulation of relay contacts and abnormal insulation of the cable often occur, so that abnormal information of double-point positions of the circuit breaker is caused, and further, false tripping occurs.
Therefore, the traditional three-phase inconsistent protection method for the circuit breaker has the problem of low control reliability.
Disclosure of Invention
In view of the above, it is necessary to provide a method, an apparatus and a system for three-phase inconsistent protection of a relay with high control reliability.
A three-phase inconsistent protection method for a circuit breaker comprises the following steps:
acquiring current and double-point position information of each phase of the circuit breaker;
judging whether the double-point position information is abnormal or not;
when the double-point position information is abnormal, calibrating the double-point position information according to the double-point position information and the change condition of the corresponding phase current to obtain double-point position correction information;
generating a control instruction according to the double-point position correction information; and the control instruction is used for indicating the relay to execute three-phase inconsistent protection actions.
In one embodiment, the calibrating the two-point position information according to the two-point position information and the change condition of the corresponding phase current when the two-point position information is abnormal to obtain two-point position correction information includes:
when the double-point position information is abnormal, judging whether the double-point position information before change is abnormal according to the change condition of the double-point position information;
if so, calibrating the double-point position information according to the current corresponding phase current to obtain double-point position correction information;
if not, the two-point position information is calibrated according to the change condition of the corresponding phase current, and two-point position correction information is obtained.
In one embodiment, after obtaining the current and the two-point position information of each phase of the circuit breaker, the method further includes:
calculating negative sequence current and/or zero sequence current according to each phase current of the circuit breaker;
judging whether the negative sequence current and/or the zero sequence current is larger than a current locking set value or not;
if yes, opening the three-phase inconsistent protection, otherwise, locking the three-phase inconsistent protection.
In one embodiment, after determining whether the two-point position information is abnormal, the method further includes:
and when the double-point position information is normal, updating the current locking set value according to the double-point position information and the change condition of the corresponding phase current.
In one embodiment, the updating the current lock setting value according to the two-point position information and the change condition of the corresponding phase current when the two-point position information is normal includes:
when the double-point position information is normal, judging whether the double-point position information is consistent with the change condition of the corresponding phase current;
if so, judging whether the maximum phase current is lower than a low-load set value or not, and subtracting a preset difference value from the current locking set value to obtain a new current locking set value under the condition that the maximum phase current is lower than the low-load set value;
if not, the current blocking set value is kept unchanged.
In one embodiment, after obtaining the current and the two-point position information of each phase of the circuit breaker, the method further includes:
judging whether the position information of the double points is in the sub-position and the condition that the current of the corresponding phase current single phase exceeds the preset time length is existed;
if yes, three-phase inconsistent protection is locked.
In one embodiment, after the three-phase inconsistent protection is locked, the method further comprises the following steps:
and outputting early warning information.
In one embodiment, the dual-point position information is GOOSE dual-point position information.
A circuit breaker three-phase inconsistent protection device comprising:
the acquisition module is used for acquiring current and double-point position information of each phase of the circuit breaker;
the judging module is used for judging whether the double-point position information is abnormal or not;
the calibration module is used for calibrating the double-point position information according to the double-point position information and the change condition of the corresponding phase current when the double-point position information is abnormal to obtain double-point position correction information;
the generating module is used for generating a control instruction according to the double-point position correction information; and the control instruction is used for indicating the relay to execute three-phase inconsistent protection actions.
In one embodiment, the calibration module is specifically configured to: when the double-point position information is abnormal, judging whether the double-point position information before change is abnormal according to the change condition of the double-point position information; if so, calibrating the double-point position information according to the current corresponding phase current to obtain double-point position correction information; if not, the two-point position information is calibrated according to the change condition of the corresponding phase current, and the two-point position correction information is obtained.
In one embodiment, the determining module is further configured to: and calculating negative sequence current and/or zero sequence current according to each phase current of the circuit breaker, and judging whether the negative sequence current and/or the zero sequence current is larger than a current locking set value or not. The inconsistent protection device of circuit breaker three-phase still includes the shutting module for: and opening the three-phase inconsistent protection when the negative sequence current and/or the zero sequence current are/is larger than the current locking set value, or locking the three-phase inconsistent protection.
In one embodiment, the three-phase inconsistent protection device of the circuit breaker further comprises an updating module for: and when the double-point position information is normal, updating the current locking set value according to the double-point position information and the change condition of the corresponding phase current.
In one embodiment, the update module is specifically configured to: when the double-point position information is normal, judging whether the double-point position information is consistent with the change condition of the corresponding phase current; if so, judging whether the maximum phase current is lower than a low-load set value or not, and subtracting a preset difference value from the current locking set value to obtain a new current locking set value under the condition that the maximum phase current is lower than the low-load set value; if not, the current blocking set value is kept unchanged.
In one embodiment, the determining module is further configured to: judging whether the position information of the double points is in the sub-position and the condition that the current of the corresponding phase current single phase exceeds the preset time length is existed; the latching module is further configured to: and locking the three-phase inconsistent protection under the condition that the position information of the double points is in the split position and the current of the corresponding phase current single phase exceeds the preset time length.
In one embodiment, the three-phase inconsistency protection device of the circuit breaker further comprises an early warning module for outputting early warning information.
A three-phase inconsistent protection system of a circuit breaker comprises a three-phase mechanism box and a controller; the three-phase mechanism box is connected with the controller;
the three-phase mechanism box is used for acquiring current and double-point position information of each phase of the circuit breaker and sending the current and the double-point position information to the controller;
the controller is used for executing the three-phase inconsistent protection method of the circuit breaker.
According to the three-phase inconsistency protection method for the relay, when the two-point position information is abnormal, the abnormal position is corrected according to the two-point position information and the change condition of the corresponding phase current, the two-point position correction information can be obtained, and the control instruction is generated according to the two-point position correction information, so that the control reliability of three-phase inconsistency protection is improved.
Drawings
FIG. 1 is a flow chart of a method for three-phase inconsistent protection of a circuit breaker according to an embodiment;
FIG. 2 is a flow chart of a three-phase inconsistent protection method for a circuit breaker in another embodiment;
FIG. 3 is a flowchart illustrating updating the current blocking setting value according to the two-point position information and the change of the corresponding phase current when the two-point position information is normal in one embodiment;
FIG. 4 is a flowchart illustrating calibration of two-point position information according to the two-point position information and the change of corresponding phase current when the two-point position information is abnormal, so as to obtain two-point position calibration information according to an embodiment;
FIG. 5 is a block diagram of an embodiment of a three-phase inconsistent protection device for a circuit breaker;
FIG. 6 is a block diagram of a three-phase inconsistent protection device of a circuit breaker in another embodiment;
FIG. 7 is a flow chart of A-phase anomaly location calibration in one embodiment;
FIG. 8 is a flowchart illustrating the phase A current dwell determination in accordance with an embodiment.
Detailed Description
To facilitate an understanding of the present application, the present application will now be described more fully with reference to the accompanying drawings. Embodiments of the present application are set forth in the accompanying drawings. This application may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.
It will be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element or be connected to the other element through intervening elements. Further, "connection" in the following embodiments is understood to mean "electrical connection", "communication connection", or the like, if there is a transfer of electrical signals or data between the connected objects.
As used herein, the singular forms "a", "an" and "the" may include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises/comprising," "includes" or "including," etc., specify the presence of stated features, integers, steps, operations, components, parts, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof. Also, as used in this specification, the term "and/or" includes any and all combinations of the associated listed items.
Taking a power grid with a voltage level of 220KV and above as an example, the currently used three-phase inconsistent protection methods for the circuit breaker mainly include the following three methods:
1. the three-phase inconsistent protection of the circuit breaker body is realized by respectively connecting A, B, C three-phase normally open auxiliary nodes and normally closed auxiliary nodes in parallel and then connecting the auxiliary nodes in series, then driving an outlet intermediate relay through a delay time relay, and tripping off the three-phase circuit breaker;
2. the common microcomputer three-phase inconsistency protection mainly adopts the auxiliary contact combination of the three-phase position of the breaker to obtain a three-phase inconsistency signal, the signal is connected into a corresponding microcomputer protection device, and the microcomputer protection device starts a protection trip outlet to trip off the three-phase breaker after a settable zero-sequence current or negative-sequence current locking criterion and settable delay time;
3. the microcomputer three-phase inconsistency protection based on the GOOSE (general Object Oriented Substation Event), namely, on the basis of the common microcomputer three-phase inconsistency protection, directly connecting three-phase separating and closing positions of the circuit breaker into a microcomputer protection device in a GOOSE transmission mode through intelligent terminal equipment, analyzing a three-phase inconsistency signal by the microcomputer protection device, and executing corresponding protection actions according to the three-phase inconsistency signal.
The inconsistent protection of above-mentioned circuit breaker three-phase all has the single problem of criterion. For three-phase inconsistent protection of the circuit breaker body, because the circuit breaker body operates under outdoor severe weather conditions for a long time, the three-phase inconsistent protection of the circuit breaker body can be mistakenly operated due to oxidation of contacts and contact shaking of an outlet relay; the secondary insulation resistance of the three-phase inconsistent protection starting circuit and the delay circuit of the circuit breaker body is aged, and the starting circuit and the delay circuit can be started and exported by mistake, so that the equipment is stopped; in addition, for a working site, all relays of the three-phase inconsistent protection circuit of the body are exposed on a panel of the control cubicle, effective anti-misoperation measures are not provided, and equipment outage accidents caused by misoperation of the circuit breaker due to mistaken touch of workers are frequently generated in the equipment maintenance process. Aiming at the microcomputer three-phase inconsistent protection, when any one of the branch and the close auxiliary nodes of the three-phase position of the circuit breaker A, B, C is damaged or abnormal, the misjudgment of the protection logic can be caused, and the protection malfunction or the failure malfunction can be caused; in addition, under the condition of small load, the zero sequence current and negative sequence current locking criterion is difficult to open, and the action of three-phase inconsistent protection is easy to be refused. Therefore, the three-phase inconsistent protection method for the relay has the problem of poor control reliability.
Based on the method, the device and the system for protecting the three-phase inconsistency of the relay, change criteria of three-phase current are introduced, and mutual correction and judgment are carried out with the change of the three-phase position, so that the correct three-phase position is identified, the abnormal position is corrected, and the misoperation and the refusal action of the three-phase inconsistency protection are effectively prevented; when the information of the double-point position is normal, the three-phase current low-load auxiliary judgment is added, mutual correction is carried out with the three-phase position through the size and the change of the three-phase current, and the locking threshold of the zero-sequence current and the negative-sequence current is dynamically adjusted, so that the action rejection of three-phase inconsistent protection is effectively prevented.
It should be noted that, in the relay three-phase inconsistency protection method in the present application, the execution process is based on the following premises:
1. the abnormality of the position of the double points and the abnormality of the alternating current circuit do not occur simultaneously;
2. all the branch and combination auxiliary nodes used by the three-phase position information are not abnormal simultaneously.
The application provides a three-phase inconsistent protection method for a circuit breaker in a first aspect. In one embodiment, as shown in fig. 1, the method includes steps S100 to S1100.
Step S100: and acquiring the current and the double-point position information of each phase of the circuit breaker.
The current of each phase of the circuit breaker refers to the current flowing through each phase of the circuit breaker. Taking three phases as an example, the breaker phase currents refer to the phase currents of the A phase, the B phase and the C phase in the breaker. Similarly, the two-point position information of each phase refers to the position information of the opening and closing of each phase of the circuit breaker. In addition, the mode of acquiring the current and the double-point position information of each phase of the circuit breaker by the controller can be actively acquired or passively received.
Further, in one embodiment, the dual-point position information is GOOSE dual-point position information. Specifically, each phase of double-point position information is transmitted in a GOOSE direct transmission mode, and a network signal is adopted to replace a hard-wired communication mode between conventional substation devices, so that on one hand, the secondary cable wiring of a power system substation can be greatly simplified, and on the other hand, the reliability, the real-time performance and the safety of transmission can be improved.
Step S800: and judging whether the double-point position information is abnormal or not.
Specifically, the double-point position information includes a separating position, a closing position, whether the separating and closing are both present or not, when the double-point position information is whether the separating and closing are both present or not, the double-point position information is judged to be abnormal, otherwise, the double-point position information is normal.
Step S1000: and when the double-point position information is abnormal, calibrating the double-point position information according to the double-point position information and the change condition of the corresponding phase current to obtain double-point position correction information.
The two-point position information and the change condition of the corresponding phase current can be determined according to the current two-point position information and the corresponding phase current, and the two-point position information and the corresponding phase current before change. Specifically, when the two-point position information is abnormal, the real two-point position information cannot be obtained, and at this time, the relationship between the two-point position information before and after the change and the corresponding phase current is analyzed according to the change condition of the two-point position information and the corresponding phase current, so that the two-point position information can be calibrated to obtain the position-dividing or position-closing two-point position correction information.
Step S1100: and generating a control command according to the double-point position correction information.
The control instruction is used for controlling the relay to execute three-phase inconsistent protection actions. Specifically, after the two-point position information of each phase is calibrated, the two-point position correction information of each phase can be obtained, and then whether the current breaker is in a three-phase inconsistent operation state or not is judged according to the two-point position correction information of each phase. If yes, generating a control instruction, and indicating a relay to execute three-phase inconsistent protection actions to perform trip protection; if not, keeping the current operation state unchanged. It can be understood that, if the two-point position information of a certain phase is abnormal, but the two-point position information of the remaining phases is normal, the two-point position information of the abnormal phase is calibrated, three-phase inconsistency judgment is performed based on the two-point position correction information obtained after calibration and the two-point position information of the remaining normal phases, and a control command is generated according to the judgment result.
According to the three-phase inconsistency protection method for the circuit breaker, when the two-point position information is abnormal, the abnormal position is corrected according to the two-point position information and the change condition of the corresponding phase current, the two-point position correction information can be obtained, and the control instruction is generated according to the two-point position correction information, so that the control reliability of three-phase inconsistency protection is improved.
In an embodiment, referring to fig. 2, after the step S100, the method further includes a step S200: and judging whether the double-point position information is in a sub-position or not and corresponding to the condition that the current of the phase current single phase exceeds the preset time length. If yes, go to step S500: and locking three-phase inconsistent protection. Step S200 may be performed before, after, or simultaneously with step S800.
The single-phase current is that the ratio of the phase current to the rated current is larger than a set value and can be set. The value of the set value is not exclusive and may be, for example, 0.05, 0.06, or 0.07. Likewise, the value of the preset time duration is not unique, and the preset time duration may be 1S or 2S, for example. Specifically, when the position of the double points of any one of the three phases is in the position of the branch and the current of the single phase exceeds the preset time, it indicates that there is a possibility of abnormal situations such as damage of the current detection device or leakage of the insulation plate. At the moment, the three-phase inconsistent protection is locked, so that the false operation of the three-phase inconsistent protection can be avoided, and the control reliability of the three-phase inconsistent protection can be further improved. Furthermore, after a branch position current blocking condition is introduced, when the three-phase inconsistent protection is in an unlocked state and a three-phase inconsistent signal exists, the controller generates a control instruction and instructs the relay to execute a three-phase inconsistent protection action according to the control instruction.
Further, with continuing reference to fig. 2, in an embodiment, after step S500, the method further includes step S700: and outputting early warning information. It is understood that in further embodiments, step S500 may be performed before, after, or simultaneously with step S500.
Wherein, the content and the output object of the early warning information are not unique. For example, the warning information may be text information that describes an abnormal situation, or may be prompt information that combines sound, light, or sound and light. The output object of the early warning information can be a memory, a display or a terminal. The terminal includes, but is not limited to, various personal computers, notebook computers, smart phones, tablet computers, and portable wearable devices. Specifically, two some position information are the branch position, and correspond the phase current single-phase have a current and exceed the condition of predetermineeing for a long time, the inconsistent protection of shutting three-phase to output early warning information, the staff of can being convenient for in time acquires abnormal information, carries out relevant processing, is favorable to further improving electric power system's security.
In one embodiment, after step S100, steps S300 to S600 are further included. Step 300 may be performed before, after, or simultaneously with step S800, and step S300 may also be performed before, after, or simultaneously with step S200, respectively.
Step S300: and calculating the negative sequence current and/or the zero sequence current according to each phase current of the circuit breaker.
The zero sequence current and the negative sequence current can be calculated according to the current of each phase of the circuit breaker collected in step S100. Specifically, the zero sequence current is the vector sum of the currents of the phases of the circuit breaker. The solving process of the negative sequence current is to fix the A phase current vector, clockwise rotate the B phase current vector by 120 degrees, anticlockwise rotate the C phase current vector by 120 degrees, add the obtained current vectors of each phase and take one third of the current vectors.
Step S400: and judging whether the negative sequence current and/or the zero sequence current is larger than the current locking set value or not.
In particular, the current blocking setpoint may be a zero sequence current and/or a negative sequence current. When the zero sequence current and/or the negative sequence current is greater than the corresponding current blocking set value, it indicates that there may be an overcurrent or a three-phase inconsistency, and at this time, step S600 is executed: and three-phase inconsistent protection is opened, so that the relay can be ensured to timely execute three-phase inconsistent protection actions. Further, if the negative sequence current and the zero sequence current are both smaller than the current locking set value, step S500 is executed: locking three-phase inconsistent protection action avoids device maloperation. Similarly, after the current blocking condition is introduced, when the three-phase inconsistency protection is in an unlocked state and a three-phase inconsistency signal exists, the controller generates a control instruction and instructs the relay to execute the three-phase inconsistency protection action according to the control instruction. The current block condition may be turned on or off by a control word.
It should be noted that, when any one of the current blocking condition and the current blocking condition is satisfied, in order to avoid device malfunction, three-phase inconsistent protection is blocked, and early warning information is output, so that the fault diagnosis and clearing can be performed by the staff in time.
In an embodiment, with continuing reference to fig. 2, after step S800, the method further includes step S900: and when the double-point position information is normal, updating the current locking set value according to the double-point position information and the change condition of the corresponding phase current.
Specifically, the controller updates the current blocking setting value according to the two-point position information and the change condition of the corresponding phase current, which is not unique. For example, the controller may appropriately lower the current latch setting value when the current latch setting value is larger than the maximum phase current, or may appropriately increase the current latch setting value when the current latch setting value is smaller than the minimum phase current, according to a magnitude relationship between the phase current and the current latch setting value.
In one embodiment, as shown in fig. 3, step S900 includes steps S920 to S960.
Step S920: when the double-point position information is normal, whether the double-point position information is consistent with the change condition of the corresponding phase current is judged. If yes, go to step S940, otherwise go to step S960.
As mentioned above, the normal double-point position information means that the double-point position information is in a separated position or a closed position. Specifically, when the two-point position information changes to the on-position shift position and the phase current changes from no current to current while the two-point position changes, or when the two-point position information changes to the on-position shift position and the phase current changes from current to no current while the two-point position changes, it is determined that the two-point position information matches the change in the corresponding phase current.
Step S940: and judging whether the maximum phase current is lower than a low-load set value or not, and subtracting a preset difference value from the current locking initial value to obtain a new current locking set value under the condition that the maximum phase current is lower than the low-load set value.
The low-load set value refers to the maximum value of the corresponding phase current in the low-load operation, and is set according to the specific responsible situation of the power system. The preset difference value can be fixed and can also be dynamically adjusted according to the size relation between the maximum phase current and the low-load set value. For example, when the difference between the maximum phase current and the low-load set value is large, subtracting a large preset difference from the current locking initial value to obtain a new current locking set value; and when the difference value between the maximum phase current and the low-load set value is smaller, subtracting a smaller preset difference value from the current locking initial value to obtain a new current locking set value.
Step S960: keeping the current blocking set value unchanged.
In the above embodiment, when the two-point position information is normal, the current blocking setting value is dynamically adjusted according to the two-point position information and the change condition of the corresponding phase current, so that the function can be flexibly switched on and off according to the actual working condition, the action rejection of three-phase inconsistency protection under low-load operation is avoided, and the control reliability of the three-phase inconsistency protection method is improved.
In one embodiment, as shown in fig. 4, step S1000 includes steps S1020 to S1060.
Step S1020: when the double-point position information is abnormal, whether the double-point position information before change is abnormal is judged according to the change condition of the double-point position information. If yes, go to step S1040, otherwise go to step S1060.
Specifically, the two-point position information before the change can be obtained according to the change condition of the two-point position information, and then the judgment of whether the two-point position information before the change is abnormal is carried out: and judging that the position information of the double points before change is abnormal when the position information of the double points before change is on or off, otherwise, judging that the position information of the double points before change is normal.
Step S1040: and calibrating the double-point position information according to the current corresponding phase current to obtain double-point position correction information.
Specifically, according to the current corresponding phase current, it can be determined whether the phase current is a single-phase current or a single-phase current. The single-phase current is that the ratio of the phase current to the rated current is larger than a set value and can be set. The single-phase no-current means that the ratio of the phase current to the rated current is smaller than a preset value and can be set. The preset value is smaller than the set value. Further, the values of the set value and the preset value are not unique, for example, the set value may be 0.05, 0.06, or 0.07, and the preset value may be 0.01, 0.02, or 0.03. If the current corresponding phase current is current, acquiring the closed position double-point position correction information; otherwise, the correction information of the position of the divided double points is obtained.
Step S1060: and calibrating the double-point position information according to the change condition of the corresponding phase current to obtain double-point position correction information.
Specifically, if the corresponding phase current changes from single-phase no-current to single-phase current, the closed position double-point position correction information is obtained; and if the corresponding phase current changes from single-phase current to single-phase current, acquiring the position correction information of the divided positions.
In the above embodiment, a specific method for position calibration when the two-point position is abnormal is provided, according to the above method, the abnormal two-point position occurring in each phase can be respectively corrected to obtain the two-point position correction information of the corresponding phase, and then the three-phase inconsistency state is determined according to the two-point position correction information, which is beneficial to improving the control reliability of three-phase inconsistency protection.
It should be understood that, although the steps in the flowcharts shown in the above embodiments are shown in sequence as indicated by the arrows, the steps are not necessarily executed in sequence as indicated by the arrows. The steps are not performed in the exact order shown and described, and may be performed in other orders, unless explicitly stated otherwise. Moreover, at least a part of the steps in each flowchart involved in the above embodiments may include multiple sub-steps or multiple stages, which are not necessarily performed at the same time, but may be performed at different times, and the order of performing the sub-steps or the stages is not necessarily sequential, but may be performed alternately or alternatingly with other steps or at least a part of the sub-steps or the stages of other steps.
The application second aspect provides a inconsistent protection device of circuit breaker three-phase. In one embodiment, as shown in fig. 5, the apparatus comprises: the acquisition module 100 is configured to acquire current and double-point position information of each phase of the circuit breaker; a judging module 200, configured to judge whether the two-point position information is abnormal; the calibration module 300 is configured to calibrate the two-point position information according to the two-point position information and a change condition of the corresponding phase current when the two-point position information is abnormal, so as to obtain two-point position correction information; a generating module 400, configured to generate a control instruction according to the two-point position correction information; the control instruction is used for instructing the relay to execute three-phase inconsistent protection actions.
In one embodiment, the dual point location information is GOOSE dual point location information.
In one embodiment, the calibration module 300 is specifically configured to: when the double-point position information is abnormal, judging whether the double-point position information before change is abnormal according to the change condition of the double-point position information; if so, calibrating the double-point position information according to the current corresponding phase current to obtain double-point position correction information; if not, the two-point position information is calibrated according to the change condition of the corresponding phase current, and the two-point position correction information is obtained.
In one embodiment, as shown in fig. 6, the determining module 200 is further configured to: and calculating the negative sequence current and/or the zero sequence current according to the current of each phase of the circuit breaker, and judging whether the negative sequence current and/or the zero sequence current is greater than a current locking set value or not. The circuit breaker three-phase inconsistent protection device further comprises a lockout module 500 for: and when the negative sequence current and/or the zero sequence current are/is larger than the current locking set value, opening the three-phase inconsistent protection, otherwise, locking the three-phase inconsistent protection.
In one embodiment, continuing to refer to fig. 6, the three-phase inconsistent protection apparatus of the circuit breaker further includes an updating module 600 for: and when the double-point position information is normal, updating the current locking set value according to the double-point position information and the change condition of the corresponding phase current.
In one embodiment, the update module 600 is specifically configured to: when the double-point position information is normal, judging whether the double-point position information is consistent with the change condition of the corresponding phase current; if so, judging whether the maximum phase current is lower than a low-load set value or not, and subtracting a preset difference value from the current locking set value to obtain a new current locking set value under the condition that the maximum phase current is lower than the low-load set value; if not, the current blocking set value is kept unchanged.
In one embodiment, the determining module 200 is further configured to: judging whether the position information of the double points is in the sub-position and the condition that the current of the corresponding phase current single phase exceeds the preset time length is existed; the latching module 500 is also used to: and locking the three-phase inconsistent protection under the condition that the position information of the double points is in the split position and the current of the corresponding phase current single phase exceeds the preset time length.
In one embodiment, please continue to refer to fig. 6, the three-phase inconsistency protection apparatus further includes an early warning module 700 for outputting early warning information.
For specific limitations of the three-phase inconsistent protection device of the circuit breaker, reference may be made to the above limitations on the three-phase inconsistent protection method of the circuit breaker, and details are not repeated here. The modules in the three-phase inconsistent protection device for the circuit breaker can be completely or partially realized by software, hardware and a combination thereof. The modules can be embedded in a hardware form or independent from a processor in the computer device, and can also be stored in a memory in the computer device in a software form, so that the processor can call and execute operations corresponding to the modules.
The application third aspect provides a inconsistent protection system of circuit breaker three-phase, including three-phase mechanism case and controller, three-phase mechanism case connection director. The three-phase mechanism box is used for acquiring current and double-point position information of each phase of the circuit breaker and sending the current and the double-point position information to the controller; the controller is used for executing the three-phase inconsistent protection method of the circuit breaker.
Wherein, in the three-phase mechanism case, be provided with current collector and position information collector, be used for gathering the electric current of each phase of circuit breaker and two some position information respectively to send to the controller. And each collector and the controller can be connected through optical fibers. Specifically, after the current and the double-point position information of each phase of the circuit breaker are acquired by each collector, the information is packaged and sent to the controller, and then the controller performs three-phase inconsistency logic judgment based on the received current and the double-point position information of each phase of the circuit breaker, and instructs the relay to perform outlet tripping and execute three-phase inconsistency protection actions.
According to the three-phase inconsistent protection system of the circuit breaker, when the two-point position information is abnormal, the controller corrects the abnormal position according to the two-point position information and the change condition of the corresponding phase current, so that two-point position correction information can be obtained, and a control instruction is generated according to the two-point position correction information, so that the control reliability of three-phase inconsistent protection is improved.
Furthermore, in one embodiment, GOOSE communication is performed between each collector and the controller in the three-phase mechanism box, so that signal acquisition and logic functions of the three-phase inconsistent loop of the body are realized through GOOSE transmission, the reliability, real-time performance and safety of transmission can be improved, and the control reliability of three-phase inconsistent protection can be further improved.
For the sake of understanding, the following describes the abnormal position calibration and the current blocking judgment in detail, taking the phase a of the circuit breaker as an example.
The phase a double-point position information may be the following four cases: the separation position (01), the combination position (10), the combination both (11) and the combination both (00). As described above, both cases of (11) both in both switching and not (00) belong to the abnormal position information. The single-phase current is that the phase current is larger than 0.06 times of rated current and can be set. The single-phase no-current means that the phase current is less than or equal to 0.02 time of rated current and can be set.
Specifically, as shown in fig. 7, when the a-phase double-point position information changes and no abnormal condition occurs, the double-point position is in open position or closed position. When an abnormal condition occurs, the calibration is respectively carried out according to the following three conditions:
1. before the A phase position information changes, the A phase is positioned in a split position, whether the A phase current changes from single-phase no-current to single-phase current when the A phase current is abnormal is judged, if yes, double-point position correction information that the A phase is in a closed position is obtained, and if not, the A phase is considered to be kept in the split position, and split double-point position correction information is obtained;
2. before the A phase position information changes, the A phase is positioned at the closed position, whether the A phase current changes from single-phase current to single-phase current or not is judged while abnormality occurs, if yes, the A phase is considered to be changed into partial position, and double-point position correction information with the A phase being partial position is obtained; if not, obtaining the double-point position correction information of which the phase A is in a closed position;
3. before the A phase position information is changed, the A phase is already in an abnormal state, whether the A phase current is single-phase current after the change is judged, if so, double-point position correction information that the A phase is in a closed position is obtained, and if not, double-point position correction information that the A phase is in a separated position is obtained.
If the B, C phase double-point position information is abnormal, the abnormal phase is also calibrated by the double-point position to obtain the corresponding phase double-point position correction information, and then the three-phase double-point position correction information is compared to determine whether the three-phase double-point position correction information is completely consistent to obtain the three-phase inconsistent signal to generate the corresponding control command. Furthermore, in order to prevent misjudgment of three-phase inconsistent signals, a fractional current blocking logic is introduced to avoid risks. When a certain phase is positioned at a branch position but the current exceeds 1s, the special abnormal condition is judged, three-phase inconsistent protection is locked, and an alarm signal is sent out in time to inform a user that related abnormity needs to be processed in time.
Further, as shown in fig. 8, when the two-point position information is changed, it is determined whether the two-point position information matches the change condition of the corresponding phase current. Specifically, when the two-point position information changes to the on-position shift position and the phase current changes from no current to current while the two-point position changes, or when the two-point position information changes to the on-position shift position and the phase current changes from current to no current while the two-point position changes, it is determined that the two-point position information matches the change in the corresponding phase current. If the two-point position information is consistent with the change situation of the corresponding phase current, further judging whether the maximum phase current in the three phases is lower than a low-load set value, properly reducing the constant value of negative sequence current and zero sequence current locking under the condition that the maximum phase current is lower than the low-load set value to obtain a low-load current locking set value, and then carrying out current locking judgment based on the obtained low-load current locking set value. If any condition in the process is not met, keeping the negative sequence current and zero sequence current locking set values unchanged, and carrying out current locking judgment based on the normal current locking set value.
As shown in the following table, by adopting the improved three-phase inconsistent protection method for the circuit breaker, the control reliability of three-phase inconsistent protection can be effectively improved.
The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above examples only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (10)
1. A three-phase inconsistent protection method for a circuit breaker is characterized by comprising the following steps:
acquiring current and double-point position information of each phase of the circuit breaker;
judging whether the double-point position information is abnormal or not;
when the double-point position information is abnormal, calibrating the double-point position information according to the double-point position information and the change condition of the corresponding phase current to obtain double-point position correction information;
generating a control instruction according to the double-point position correction information; and the control instruction is used for indicating the relay to execute three-phase inconsistent protection actions.
2. The three-phase inconsistent protection method for the circuit breaker according to claim 1, wherein the calibrating the two-point position information according to the two-point position information and the change condition of the corresponding phase current when the two-point position information is abnormal to obtain the two-point position correction information comprises:
when the double-point position information is abnormal, judging whether the double-point position information before change is abnormal according to the change condition of the double-point position information;
if so, calibrating the double-point position information according to the current corresponding phase current to obtain double-point position correction information;
if not, the two-point position information is calibrated according to the change condition of the corresponding phase current, and two-point position correction information is obtained.
3. The three-phase inconsistent protection method for the circuit breaker according to claim 1, wherein after obtaining the current and the double-point position information of each phase of the circuit breaker, the method further comprises:
calculating negative sequence current and/or zero sequence current according to each phase current of the circuit breaker;
judging whether the negative sequence current and/or the zero sequence current is larger than a current locking set value or not;
if yes, opening the three-phase inconsistent protection, otherwise, locking the three-phase inconsistent protection.
4. The three-phase inconsistent protection method for the circuit breaker according to claim 3, wherein after judging whether the two-point position information is abnormal, the method further comprises the following steps:
and when the double-point position information is normal, updating the current locking set value according to the double-point position information and the change condition of the corresponding phase current.
5. The three-phase inconsistent protection method for the circuit breaker according to claim 4, wherein when the two-point position information is normal, the updating the current blocking setting value according to the two-point position information and the change condition of the corresponding phase current comprises:
when the double-point position information is normal, judging whether the double-point position information is consistent with the change condition of the corresponding phase current;
if so, judging whether the maximum phase current is lower than a low-load set value or not, and subtracting a preset difference value from the current locking set value to obtain a new current locking set value under the condition that the maximum phase current is lower than the low-load set value;
if not, the current blocking set value is kept unchanged.
6. The three-phase inconsistent protection method for the circuit breaker according to any one of claims 1 to 5, wherein after obtaining the current and the double-point position information of each phase of the circuit breaker, the method further comprises:
judging whether the position information of the double points is in the sub-position and the condition that the current of the corresponding phase current single phase exceeds the preset time length is existed;
if yes, three-phase inconsistent protection is locked.
7. The method of claim 6, wherein after the blocking the three-phase inconsistent protection, further comprising:
and outputting early warning information.
8. The three-phase inconsistent protection method for the circuit breaker according to any one of claims 1 to 5, wherein the two-point position information is GOOSE two-point position information.
9. A circuit breaker three-phase inconsistent protection device, comprising:
the acquisition module is used for acquiring current and double-point position information of each phase of the circuit breaker;
the judging module is used for judging whether the double-point position information is abnormal or not;
the calibration module is used for calibrating the double-point position information according to the double-point position information and the change condition of the corresponding phase current when the double-point position information is abnormal to obtain double-point position correction information;
the generating module is used for generating a control instruction according to the double-point position correction information; and the control instruction is used for indicating the relay to execute three-phase inconsistent protection actions.
10. A three-phase inconsistent protection system of a circuit breaker is characterized by comprising a three-phase mechanism box and a controller; the three-phase mechanism box is connected with the controller;
the three-phase mechanism box is used for acquiring current and double-point position information of each phase of the circuit breaker and sending the current and the double-point position information to the controller;
the controller is used for executing the three-phase inconsistent protection method of the circuit breaker according to any one of claims 1 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110775189.1A CN113541110A (en) | 2021-07-08 | 2021-07-08 | Three-phase inconsistent protection method, device and system for circuit breaker |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110775189.1A CN113541110A (en) | 2021-07-08 | 2021-07-08 | Three-phase inconsistent protection method, device and system for circuit breaker |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113541110A true CN113541110A (en) | 2021-10-22 |
Family
ID=78098121
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110775189.1A Pending CN113541110A (en) | 2021-07-08 | 2021-07-08 | Three-phase inconsistent protection method, device and system for circuit breaker |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113541110A (en) |
-
2021
- 2021-07-08 CN CN202110775189.1A patent/CN113541110A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110794355B (en) | Bus current transformer disconnection identification method, differential protection method and device | |
| US20220131366A1 (en) | Primary and system protection for an electric power delivery system | |
| CN110460025B (en) | Quick ring-opening method and device | |
| CA2704338A1 (en) | Fault protection device with ground trip delay and method | |
| US6671151B2 (en) | Network protector relay and method of controlling a circuit breaker employing two trip characteristics | |
| CN109839575B (en) | Power system fault processing method and device and terminal equipment | |
| CN110474288A (en) | Programmable microcomputer protecting device | |
| CN112363005B (en) | GIS combined electrical apparatus fault detection and processing method, device and storage medium | |
| CN112736867B (en) | Method and system for rapidly judging CT disconnection of line protection device | |
| US11108737B2 (en) | Secure electric power delivery system protection during cyber threats | |
| CN113541110A (en) | Three-phase inconsistent protection method, device and system for circuit breaker | |
| CN116780747A (en) | Method for improving action accuracy rate during disconnection of sectional spare power automatic switching voltage | |
| CN109142954B (en) | T-zone protection CT disconnection identification method and differential protection method | |
| CN110687443A (en) | Primary equipment state discrimination method and system | |
| CN112039083B (en) | Control method and device for load transfer across bypass buses | |
| CN113964799A (en) | Method and device for preventing differential protection unwanted operation at two ends of T area | |
| KR102539523B1 (en) | A appartus for caculation parameters of protection coordination of multi circuit breaker | |
| CN111799764B (en) | Method, device and system for preventing zero sequence protection of homonymous single-phase fault from being refused | |
| CN108736448A (en) | A kind of MKB motors accident alarming processing method | |
| CN116466154B (en) | Fault diagnosis method and device, storage medium and electronic equipment | |
| CN110504682B (en) | High-voltage direct-current system alternating current bus splitting operation tripping control method and device | |
| WO2024105741A1 (en) | Control device, power supply control system, setting value determination method, and program | |
| US20220069566A1 (en) | Electric power system differential protection with dc compensation | |
| JPH10341531A (en) | Overload monitoring system for transformer | |
| JPH05276644A (en) | Protective relay unit and set point calculating unit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |