CN114629088A - Power-loss protection method and system for line protection direct current screen - Google Patents
Power-loss protection method and system for line protection direct current screen Download PDFInfo
- Publication number
- CN114629088A CN114629088A CN202210231652.0A CN202210231652A CN114629088A CN 114629088 A CN114629088 A CN 114629088A CN 202210231652 A CN202210231652 A CN 202210231652A CN 114629088 A CN114629088 A CN 114629088A
- Authority
- CN
- China
- Prior art keywords
- direct current
- current screen
- power
- signal
- line protection
- 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
- 238000000034 method Methods 0.000 title claims abstract description 21
- 238000010586 diagram Methods 0.000 description 9
- 238000004590 computer program Methods 0.000 description 7
- 230000006870 function Effects 0.000 description 4
- 230000001681 protective effect Effects 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
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
- H02H7/268—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 for dc systems
-
- 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
Landscapes
- Emergency Protection Circuit Devices (AREA)
Abstract
The invention discloses a power-off protection method for a line protection direct current screen, which comprises the following steps: acquiring a direct-current screen power supply input signal of a line protection device on two sides of a line; the line protection devices on the two sides respectively give a virtual open signal; the line protection device on the side transmits a direct current screen power supply switching-on signal and a virtual switching-on signal to the line protection device on the opposite side respectively; the line protection device on each side judges whether the opposite side direct current screen loses power or not through the time difference between the signal return time of the power supply on the opposite side direct current screen and the signal return time of the virtual on-off signal; if the power loss of the side direct current screen is carried out, the power loss protection is carried out, the power loss condition of the direct current screen is rapidly and accurately judged by utilizing the time difference between the return time of the power input signal of the side direct current screen and the return time of the virtual input signal, though the time difference is not complex, the time difference is ingenious, the tripping operation can be carried out on the power loss in time, and the risk of the unprotected operation of a circuit is eliminated at the first time.
Description
Technical Field
The invention belongs to the technical field of power system relay protection, and particularly relates to a power-off protection method and system for a line protection direct-current screen.
Background
Two line protection devices are arranged on two sides of the power transmission line and used for protecting the primary power transmission line, the main protection of the line protection devices is usually longitudinal differential protection, is double-end quantity protection, and mutually transmits information on two sides through a longitudinal communication channel; the backup protection mainly comprises three-section distance protection and the like, and is single-end protection, wherein the distance I section usually protects 70% -80% of the total length of the line, and the distance II section has a protection range exceeding the total length of the line but has certain action time delay.
When the direct current screen of the line protection device on one side loses power (the power loss side), the line protection device quits operation, the main protection of the line protection device on the other side (the normal side) cannot normally operate, only the backup protection continues to operate, the protection range only comprises 70% -80% of the full length of the line, and the protection range is reduced; in addition, when a line fails, the normal side line protection cannot trip off the power failure side switch, so that the accident influence range is expanded, and the stable operation of the system is damaged.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a line protection direct-current screen power-loss protection method which can judge and protect the direct-current screen power-loss of a line protection device.
The technical problem to be solved by the invention is realized by the following technical scheme:
in a first aspect, a method for protecting a line protection direct current screen from power loss is provided, which includes:
acquiring a direct-current screen power supply input signal of a line protection device on two sides of a line;
the line protection devices on two sides respectively give a virtual open signal;
the line protection device on the side transmits a direct current screen power supply switching-on signal and a virtual switching-on signal to the line protection device on the opposite side respectively;
the line protection device on each side judges whether the opposite side direct current screen loses power or not through the time difference between the signal return time of the power supply on the opposite side direct current screen and the signal return time of the virtual on-off signal;
and if the side direct current screen loses power, power loss protection is carried out. A
With reference to the first aspect, further, the determining whether the power of the opposite-side dc screen is lost through the time difference between the return time of the input signal of the power supply of the opposite-side dc screen and the return time of the virtual input signal includes:
given time intervals ta and tc, ts is more than ta and less than tc, ts is the time for the line protection device to maintain power supply after the power supply of the direct-current screen is powered off,
and if the ta is less than td and less than tc, judging that the opposite side direct current screen loses power, wherein td is the time difference between the return time of the power supply opening signal of the opposite side direct current screen and the return time of the virtual opening signal.
With reference to the first aspect, further, the power loss protection includes:
if the second judgment data control word of the direct current power loss protection is 0, directly tripping after given time delay tck;
and if the second judgment data of the direct current power loss protection is 1, judging whether the opposite side direct current screen is powered down by the same method, if the opposite side direct current screen is still judged to be powered down, tripping after a given delay tck, otherwise not tripping.
In combination with the first aspect, further, tck is 1 s.
In a second aspect, a line protection dc-screen power loss protection system is provided, including:
the signal acquisition module is used for acquiring direct-current screen power supply switching-on signals of the line protection devices on two sides of the line;
the line protection devices on the two sides respectively give a virtual open signal;
the line protection device on the side transmits a direct current screen power supply switching-on signal and a virtual switching-on signal to the line protection device on the opposite side respectively; the power failure judging module is used for judging whether the opposite side direct current screen is in power failure or not by the line protection device on each side through the time difference between the return time of the power supply input signal of the opposite side direct current screen and the return time of the virtual input signal;
and the power-off protection module is used for performing power-off protection if the opposite side direct current screen loses power.
With reference to the second aspect, further, the content executed by the power loss determination module includes: and setting time intervals ta and tc, enabling ta to be smaller than ts and smaller than tc, wherein ts is the time for the line protection device to maintain power supply after the power supply of the direct current screen is powered down, and if ta is smaller than td and smaller than tc, judging that the opposite direct current screen is powered down, wherein td is the time difference between the return moment of the input signal of the opposite direct current screen power supply and the return moment of the virtual input signal.
The third aspect, a line protection direct current screen loses electric protection system, its characterized in that includes:
comprising a memory and a processor;
the memory is to store instructions;
the processor is configured to operate in accordance with the instructions to perform the steps of the method according to any one of the first aspect.
The invention has the beneficial effects that: the invention judges the power failure condition of the direct current screen rapidly and accurately by utilizing the time difference between the power on signal return time of the opposite direct current screen and the virtual power on signal return time, is not complex but is ingenious, can carry out tripping operation treatment on the power failure in time, and eliminates the risk of unprotected operation of a circuit at the first time.
Drawings
FIG. 1 is a schematic diagram of signal access in the present invention;
FIG. 2 is a flow chart of a logic implementation of the present invention.
Detailed Description
To make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is apparent that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
For better understanding of the present invention, the related art in the technical solution of the present invention is explained below.
Example 1
As shown in fig. 1-2, a method for protecting a line protection dc screen from power loss of the present invention includes the following steps:
step one, signal acquisition
The line protection device is connected with an open-in contact of the line protection device through a direct current source of a line protection device screen cabinet, the open-in contact is an external open-in signal, the open-in is 1 when the direct current screen is normal, and the open-in is 0 when the direct current screen is in power failure.
The line protection device sets a virtual open signal through software, and fixes the line protection device to be 1.
Two input quantities are added to the channel information of the line protection device and transmitted to the opposite side, namely the external input signal and the virtual input signal.
Step two, judging the power loss of the direct current screen
Because the power supply of the line protection device can maintain that ts is 100ms for normal power supply after power failure, when the time when the virtual open signal received by the line protection device on the side is shifted from 1 to 0 lags the time when the external open signal is shifted from 1 to 0, the power failure is judged by using the time difference, the given time period ta is 50ms and tc is 200ms (set according to experience), and the given time period ta is less than ts and less than tc.
And if the ta is less than td and less than tc, judging that the opposite side direct current screen loses power, wherein td is the time difference between the return time of the power supply opening signal of the opposite side direct current screen and the return time of the virtual opening signal.
Step three, power loss protection
The invention adopts double protective devices, judges whether the power is lost or not through the first protective device in the step two, and the subsequent judgment is established on the basis that the first protective device judges that the power is lost
Before starting power loss protection (whether switching off is performed or not), a second judgment data control word of direct current power loss protection is judged, if the second judgment data control word of direct current power loss protection is 0, the system does not need to judge second protection, the system is directly tripped to complete protection after given delay tck, if the second judgment data control word of direct current power loss protection is 1, the system needs to perform second protection and confirm power loss again, whether the opposite side direct current screen is powered off or not is judged by the same method in the second protection device step II, if the system is still judged to be powered off, the system is tripped after given delay tck, otherwise, the system is not tripped, and the time length of tck is set to be 1 s.
Example 2
The invention also provides a power-off protection system of the line protection direct current screen, which comprises the following components:
the signal acquisition module is used for acquiring direct-current screen power supply switching-on signals of the line protection devices on two sides of the line;
the line protection devices on the two sides respectively give a virtual open signal;
the line protection device on the side transmits a direct current screen power supply switching-on signal and a virtual switching-on signal to the line protection device on the opposite side respectively; the power failure judging module is used for judging whether the opposite side direct current screen is in power failure or not by the line protection device on each side through the time difference between the return time of the power supply input signal of the opposite side direct current screen and the return time of the virtual input signal;
and the power-off protection module is used for performing power-off protection if the opposite side direct current screen loses power.
Example 3
A line protection direct current screen loses electric protection system, includes:
comprising a memory and a processor;
the memory is to store instructions;
the processor is used for operating according to the instruction to execute the steps of any one of the line protection direct current screen power-off protection methods.
As will be appreciated by one skilled in the art, embodiments of the present invention 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.
The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.
Claims (7)
1. A power-off protection method for a line protection direct current screen is characterized by comprising the following steps:
acquiring a direct-current screen power supply input signal of a line protection device on two sides of a line;
the line protection devices on the two sides respectively give a virtual open signal;
the line protection device on the side transmits a direct current screen power supply switching-on signal and a virtual switching-on signal to the line protection device on the opposite side respectively;
the line protection device on each side judges whether the opposite side direct current screen loses power or not through the time difference between the signal return time of the power supply on the opposite side direct current screen and the signal return time of the virtual on-off signal;
and if the side direct current screen loses power, power loss protection is carried out.
2. The line protection direct current screen power-loss protection method according to claim 1, wherein the determining whether the opposite direct current screen is powered down through the time difference between the return time of the power supply input signal of the opposite direct current screen and the return time of the virtual input signal comprises:
given time intervals ta and tc, ts is more than ta and less than tc, ts is the time for the line protection device to maintain power supply after the power supply of the direct-current screen is powered off,
and if the ta is less than td and less than tc, judging that the opposite side direct current screen loses power, wherein td is the time difference between the return time of the power supply opening signal of the opposite side direct current screen and the return time of the virtual opening signal.
3. The line protection direct current screen power-off protection method according to claim 1, wherein the power-off protection comprises:
if the second judgment data control word of the direct current power loss protection is 0, directly tripping after a given time delay tck;
and if the second judgment data of the direct current power loss protection is 1, judging whether the opposite side direct current screen is powered down by the same method, if the opposite side direct current screen is still judged to be powered down, tripping after a given delay tck, otherwise not tripping.
4. The method according to claim 1, wherein tck is 1 s.
5. The utility model provides a line protection direct current screen loses electric protection system which characterized in that includes:
the signal acquisition module is used for acquiring direct-current screen power supply switching-on signals of the line protection devices on two sides of the line;
the line protection devices on the two sides respectively give a virtual open signal;
the line protection device on the side transmits a direct current screen power supply switching-on signal and a virtual switching-on signal to the line protection device on the opposite side respectively;
the power failure judging module is used for judging whether the opposite side direct current screen is in power failure or not by the line protection device on each side through the time difference between the return time of the power supply input signal of the opposite side direct current screen and the return time of the virtual input signal;
and the power-off protection module is used for performing power-off protection if the opposite side direct current screen loses power.
6. The line protection direct current screen power-off protection method according to claim 1, wherein the power-off judging module executes contents including: and setting time intervals ta and tc, enabling ta to be smaller than ts and smaller than tc, wherein ts is the time for the line protection device to maintain power supply after the power supply of the direct current screen is powered down, and if ta is smaller than td and smaller than tc, judging that the opposite direct current screen is powered down, wherein td is the time difference between the return moment of the input signal of the opposite direct current screen power supply and the return moment of the virtual input signal.
7. The utility model provides a line protection direct current screen loses electric protection system which characterized in that includes:
comprising a memory and a processor;
the memory is to store instructions;
the processor is configured to operate in accordance with the instructions to perform the steps of the method according to any one of claims 1 to 4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210231652.0A CN114629088A (en) | 2022-03-09 | 2022-03-09 | Power-loss protection method and system for line protection direct current screen |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210231652.0A CN114629088A (en) | 2022-03-09 | 2022-03-09 | Power-loss protection method and system for line protection direct current screen |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114629088A true CN114629088A (en) | 2022-06-14 |
Family
ID=81899664
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210231652.0A Pending CN114629088A (en) | 2022-03-09 | 2022-03-09 | Power-loss protection method and system for line protection direct current screen |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114629088A (en) |
-
2022
- 2022-03-09 CN CN202210231652.0A patent/CN114629088A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113156268A (en) | Voltage time type or current type based fault positioning method, device and equipment | |
| CN114629088A (en) | Power-loss protection method and system for line protection direct current screen | |
| CN114076894A (en) | Method and device for detecting operation of disconnecting link, electronic equipment and storage medium | |
| CN111224371A (en) | Relay protection method for power system | |
| CN113138335B (en) | Method and system for detecting Bluetooth circuit breaker | |
| CN110995336B (en) | OLP transmission link switching method and device, storage medium and OLP | |
| CN110138016B (en) | Overload stability control method and system for multiple feedback output lines of power plant and related components | |
| CN115036593A (en) | Battery management system, battery system unit and battery system | |
| CN115912282A (en) | Master-slave differential protection method and system based on mobile communication | |
| CN204481467U (en) | Intelligent grid middle voltage bus bar protection measurement and control integration device | |
| CN117134638B (en) | Upgrade method, inverter, parallel operation system and readable storage medium | |
| CN210007366U (en) | stable control device for electric power system | |
| CN114726087B (en) | Distribution network feeder automation fault processing method, system and electronic equipment | |
| CN103501043A (en) | Low-voltage dual-power circuit based on PLC (Programmable Logic Controller) | |
| JPS609330A (en) | System switching controller | |
| CN114002540B (en) | Power distribution network line development fault protection method and system | |
| CN111146771B (en) | Transformer substation equipment bus difference unification method and device | |
| CN113067314B (en) | Substation area protection method and device for coping with voltage loss of direct-current power supply for substation | |
| CN110994535B (en) | Method and system for judging disconnection of excitation voltage measurement circuit | |
| CN107977067A (en) | A kind of mobile unit system automatic switching protective device | |
| EP4277111A1 (en) | Fast disconnects for generator systems | |
| CN108988302B (en) | Bus tie circuit processing method and device | |
| An et al. | Research on Reaction Phase to Phase Fault Location and Protection of Distribution Network | |
| CN117825941A (en) | SVG soft start switch closing fault detection method, device and medium | |
| CN111478291A (en) | Relay protection method and device for smart home |
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 |