CN112993948A - Circuit and method for preventing relay protection misoperation in loop closing operation - Google Patents
Circuit and method for preventing relay protection misoperation in loop closing operation Download PDFInfo
- Publication number
- CN112993948A CN112993948A CN202110203912.9A CN202110203912A CN112993948A CN 112993948 A CN112993948 A CN 112993948A CN 202110203912 A CN202110203912 A CN 202110203912A CN 112993948 A CN112993948 A CN 112993948A
- Authority
- CN
- China
- Prior art keywords
- switch
- current
- load
- limiting
- loss
- 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 22
- 230000001603 reducing effect Effects 0.000 claims description 7
- 230000000694 effects Effects 0.000 abstract description 3
- 238000001514 detection method Methods 0.000 description 3
- 230000007257 malfunction Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 1
- 230000001360 synchronised effect 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
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
- H02H9/02—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess current
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Emergency Protection Circuit Devices (AREA)
Abstract
The invention discloses a circuit and a method for preventing relay protection misoperation in loop closing operation, wherein the method comprises the following steps: the current-limiting impedance and the second switch are connected in parallel to form a current-limiting loss-reducing device, and the current-limiting loss-reducing device is connected in series in the loop-closing loop; normally running, opening a third switch, closing a first switch, and supplying power to a third load by a first voltage through the first load and the first switch; and when the third load needs to be supplied, the second switch is opened, the third switch is closed, the first switch is opened after the system enters the stable state, and the second switch is closed after the system enters the stable state again. The invention has the advantages that the current-limiting and loss-reducing device is connected into the loop closing loop, the current-limiting and loss-reducing device plays a role in current limiting during transfer, the loss-reducing and energy-saving effect is played after the transfer is finished, the problems that the voltage amplitude phases at two sides of the loop closing are difficult to adjust in the actual work of a power grid, power failure switching can not be carried out, and the situations of changing or quitting protection can not be realized are solved, and the invention has certain innovation and good practicability.
Description
Technical Field
The invention relates to the technical field of circuit protection, in particular to a circuit and a method for preventing relay protection misoperation in loop closing operation.
Background
The prior art has methods of synchronous detection, power failure switching-off, modification or exit protection and the like for the power grid loop closing operation. However, these methods still have the following aspects that cannot meet the requirements of the power grid application. The method for detecting the synchronization condition adjusts the voltage frequency, the phase and the amplitude at two sides of grid connection, and grid connection is carried out when the condition is met, but in an actual power grid, when the voltage frequency, the phase and the amplitude at two sides of a closed loop point are not adjustable, the method is limited in application; the power failure and switching can cause short-time power failure of users, so that the user is not practical; modifying and removing the protection increases the grid risk or disables the protection function.
Disclosure of Invention
The invention aims to provide a circuit and a method for preventing relay protection misoperation in loop closing operation, which can solve the problems that the voltage amplitude phase at two sides of a loop cannot be adjusted, power failure switching and situations of changing or quitting protection cannot be realized in the prior art.
The purpose of the invention is realized by the following technical scheme:
in a first aspect, the invention provides a circuit for preventing relay protection misoperation in loop closing operation, which comprises a first voltage, a second voltage, a first load, a second load, a third load and a current-limiting loss-reducing device, wherein the first voltage is higher than the second voltage;
the first voltage is used for supplying power to a third load, one end of the first voltage is connected with one end of the third load, the other end of the first voltage is sequentially connected with the first load and a first switch in series, and the first switch is connected with the other end of the third load;
the second voltage is used for supplying power to the third load during switching, one end of the second voltage is connected with one end of the third load, the other end of the second voltage is sequentially connected with the second load, the current-limiting loss-reducing device and the third switch in series, and the third switch is connected with the other end of the third load.
Further, the current-limiting and loss-reducing device comprises a current-limiting impedance and a second switch connected in parallel with the current-limiting impedance.
Further, the current limiting impedance is resistive or resistive.
In a second aspect, the present invention provides a method for preventing relay protection malfunction during loop closing operation, which comprises connecting a current-limiting impedance and a second switch in parallel to form a current-limiting loss-reducing device, and connecting the current-limiting loss-reducing device in series in a loop closing loop; normally running, opening a third switch, closing a first switch, and supplying power to a third load by a first voltage through the first load and the first switch; and when the third load needs to be supplied, the second switch is opened, the third switch is closed, the first switch is opened after the system enters the stable state, and the second switch is closed after the system enters the stable state again.
The current-limiting and loss-reducing device is formed by connecting the current-limiting impedance and the second switch in parallel, the current-limiting and loss-reducing device is connected into the closed loop in series, and when the third load needs to be supplied, the current-limiting and loss-reducing device can play a role in limiting current in the closed loop due to the fact that the current-limiting impedance is communicated; after the switching supply is finished, the second switch is closed to short-circuit the current-limiting impedance, active loss and voltage loss of a power supply loop are reduced, and the loss reducing effect is achieved. The circuit design of the invention solves the problem that the synchronization detection method, the power failure switching method, the modification or quit protection method and other methods in the prior art can not meet the application requirements of the power grid, and provides a new solution, which has innovation and practicability.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
Fig. 1 is a schematic diagram of a circuit for preventing a relay protection malfunction in a loop closing operation according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. 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.
Referring to fig. 1, the circuit for preventing the relay protection from malfunction during the loop closing operation of the present invention includes a first voltage V1, a second voltage V2, a first load Z1, a second load Z2, a third load Z, and a current limiting and loss reducing device a.
The first voltage V1 is used for supplying power to the third load Z, one end of the first voltage V1 is connected to one end of the third load Z, the other end of the first voltage V1 is connected in series with the first load Z1 and the first switch B1, and the first switch B1 is connected to the other end of the third load Z.
And the second voltage V2 is used for supplying power to a third load Z during switching, one end of the second voltage V2 is connected with one end of the third load Z, the other end of the second voltage V2 is sequentially connected with the second load Z2, the current-limiting loss-reducing device A and a third switch B3 in series, and the third switch B3 is connected with the other end of the third load Z.
In a specific implementation, the current-limiting and loss-reducing device a includes a current-limiting impedance R and a second switch B2 connected in parallel with the current-limiting impedance R. The current limiting impedance R and the second switch B2 connected in parallel are connected in series in the loop.
Preferably, the current limiting impedance R is resistive or resistive.
The invention discloses a method for preventing relay protection misoperation in loop closing operation, which comprises the steps of connecting a current-limiting impedance R and a second switch B2 in parallel to form a current-limiting loss reducing device A, and connecting the current-limiting loss reducing device A in a loop closing loop in series; normal operation opens the third switch B3, closes the first switch B1, and the third load Z is powered by the first voltage V1 through the first load Z1 and the first switch B1; when the third load Z needs to be supplied, the second switch B2 is opened, the third switch B3 is closed, the first switch B1 is opened after the system enters a steady state, and the second switch B2 is closed after the system enters the steady state again.
It should be noted that, when the third load Z needs to be supplied, the second switch B2 is opened, the third switch B3 is closed, at this time, since the current-limiting impedance R is connected, the current-limiting impedance R has a current-limiting effect in the closed-loop circuit, after the system enters a steady state, the first switch B1 is opened, and after the system enters the steady state again, the second switch B2 is closed, at this time, due to the short-circuit current-limiting impedance R, active loss and voltage loss of the power supply circuit are reduced, and the effects of reducing loss and saving energy are achieved.
The current-limiting and loss-reducing device is formed by connecting the current-limiting impedance and the second switch in parallel, the current-limiting and loss-reducing device is connected into the closed loop in series, and when the third load needs to be supplied, the current-limiting and loss-reducing device can play a role in limiting current in the closed loop due to the fact that the current-limiting impedance is communicated; after the switching supply is finished, the second switch is closed to short-circuit the current-limiting impedance, active loss and voltage loss of a power supply loop are reduced, and the loss reducing effect is achieved. The circuit design of the invention solves the problem that the synchronization detection method, the power failure switching method, the modification or quit protection method and other methods in the prior art can not meet the application requirements of the power grid, and provides a new solution, which has innovation and practicability.
In addition, the circuit and the method for preventing the relay protection from the false operation in the loop closing operation according to the embodiments of the present invention are described in detail, and a specific example is used herein to explain the principle and the implementation of the present invention, and the description of the above embodiment is only used to help understanding the method and the core idea of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.
Claims (4)
1. A circuit for preventing relay protection misoperation in closed loop operation is characterized by comprising a first voltage (V1), a second voltage (V2), a first load (Z1), a second load (Z2), a third load (Z) and a current-limiting loss-reducing device (A);
the first voltage (V1) is used for supplying power to a third load (Z), one end of the first voltage (V1) is connected with one end of the third load (Z), the other end of the first voltage (V1) is sequentially connected with the first load (Z1) and a first switch (B1) in series, and the first switch (B1) is connected with the other end of the third load (Z);
the second voltage (V2) is used for supplying power to the third load (Z) in the process of switching power, one end of the third load (Z) is connected with one end of the second voltage (V2), the other end of the third voltage (V2) is sequentially connected with the second load (Z2), the current-limiting loss-reducing device (A) and the third switch (B3) in series, and the third switch (B3) is connected with the other end of the third load (Z).
2. The circuit for preventing the relay protection of the loop closing operation from malfunctioning as claimed in claim 1, wherein the current limiting and loss reducing means (a) comprises a current limiting impedance (R) and a second switch (B2) connected in parallel with the current limiting impedance (R).
3. The circuit for preventing the relay protection from the loop closing operation as claimed in claim 2, wherein the current limiting impedance (R) is resistive or resistive.
4. A method for preventing relay protection misoperation in closed loop operation is characterized by comprising the steps of connecting a current-limiting impedance (R) and a second switch (B2) in parallel to form a current-limiting loss-reducing device (A), and connecting the current-limiting loss-reducing device (A) in series in a closed loop; normal operation opens the third switch (B3), closes the first switch (B1), and the third load (Z) is supplied by the first voltage (V1) through the first load (Z1) and the first switch (B1); when the third load (Z) needs to be transferred, the second switch (B2) is opened, the third switch (B3) is closed, the first switch (B1) is opened after the system enters a steady state, and the second switch (B2) is closed after the system enters the steady state again.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110203912.9A CN112993948A (en) | 2021-02-23 | 2021-02-23 | Circuit and method for preventing relay protection misoperation in loop closing operation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110203912.9A CN112993948A (en) | 2021-02-23 | 2021-02-23 | Circuit and method for preventing relay protection misoperation in loop closing operation |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112993948A true CN112993948A (en) | 2021-06-18 |
Family
ID=76350455
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110203912.9A Pending CN112993948A (en) | 2021-02-23 | 2021-02-23 | Circuit and method for preventing relay protection misoperation in loop closing operation |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112993948A (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20150069842A1 (en) * | 2013-09-06 | 2015-03-12 | Delta Electronics, Inc. | Power supply conversion system and method of controlling the same |
| CN104917297A (en) * | 2015-06-30 | 2015-09-16 | 中国舰船研究设计中心 | Electric ship power grid monitoring protection device and endurance monitoring method |
| CN105762921A (en) * | 2016-01-27 | 2016-07-13 | 江苏省电力公司南京供电公司 | Superconducting fault current limiter-based loop closing switching power supply method |
| CN107508457A (en) * | 2017-09-08 | 2017-12-22 | 中国船舶重工集团公司第七0四研究所 | Direct-current dual power starts and switching current-limiting circuit |
| CN208353061U (en) * | 2018-06-15 | 2019-01-08 | 甘肃酒钢集团宏兴钢铁股份有限公司 | A kind of passive switch of UPS bypass |
| CN110401194A (en) * | 2019-08-15 | 2019-11-01 | 西安热工研究院有限公司 | A kind of fast cutting system of three power supply of Combined cycle gas-steam turbine distributed energy and method |
| CN112049728A (en) * | 2020-09-11 | 2020-12-08 | 北京动科瑞利文科技有限公司 | Uninterrupted operation system and method based on vehicle-mounted gas turbine generator set |
-
2021
- 2021-02-23 CN CN202110203912.9A patent/CN112993948A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20150069842A1 (en) * | 2013-09-06 | 2015-03-12 | Delta Electronics, Inc. | Power supply conversion system and method of controlling the same |
| CN104917297A (en) * | 2015-06-30 | 2015-09-16 | 中国舰船研究设计中心 | Electric ship power grid monitoring protection device and endurance monitoring method |
| CN105762921A (en) * | 2016-01-27 | 2016-07-13 | 江苏省电力公司南京供电公司 | Superconducting fault current limiter-based loop closing switching power supply method |
| CN107508457A (en) * | 2017-09-08 | 2017-12-22 | 中国船舶重工集团公司第七0四研究所 | Direct-current dual power starts and switching current-limiting circuit |
| CN208353061U (en) * | 2018-06-15 | 2019-01-08 | 甘肃酒钢集团宏兴钢铁股份有限公司 | A kind of passive switch of UPS bypass |
| CN110401194A (en) * | 2019-08-15 | 2019-11-01 | 西安热工研究院有限公司 | A kind of fast cutting system of three power supply of Combined cycle gas-steam turbine distributed energy and method |
| CN112049728A (en) * | 2020-09-11 | 2020-12-08 | 北京动科瑞利文科技有限公司 | Uninterrupted operation system and method based on vehicle-mounted gas turbine generator set |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN204244113U (en) | A kind of control circuit of soft initiator | |
| CN201374571Y (en) | Online UPS | |
| CN106300398B (en) | Interphase load transfer terminal device based on steady-state waveform fitting | |
| CN112701731A (en) | Energy storage microgrid grid-connection and off-grid seamless switching device, method and system | |
| CN2907083Y (en) | Soft starter for high power industrial frequency transformer | |
| CN105656388B (en) | A kind of frequency converter soft start synchronizes the implementation method of grid-connected lock phase | |
| CN107887967A (en) | Transformer station's in-put of spare power supply method containing wind power integration in main power supply | |
| CN201576957U (en) | Variable frequency power supply control system of low-voltage motor | |
| CN112993948A (en) | Circuit and method for preventing relay protection misoperation in loop closing operation | |
| CN205901423U (en) | Contactor type dual -power -supply switching device with wrong looks, open -phase protection function | |
| CN209608349U (en) | Novel little electric wire netting control device | |
| CN102868214A (en) | utomatic standby power supply switching box in small water power station | |
| CN111371092B (en) | Automatic control method, device, equipment and storage medium for self-healing of power distribution network | |
| CN109412466A (en) | The compound start stop apparatus of turbine emergency DC lubricating and control method | |
| CN202260481U (en) | Dynamic voltage restorer for three-phase four-wire system distribution network | |
| CN110350650B (en) | High-capacity high-reliability rapid power supply switching device and switching control method thereof | |
| CN208874294U (en) | A kind of automatic switching control equipment of pair of generating set reactive compensation | |
| CN205452022U (en) | Capacity-adjusting energy-saving transformer | |
| CN218997767U (en) | Power supply spare power automatic switching control circuit | |
| CN201467040U (en) | Auto-coupling voltage-reduction starting control device | |
| CN207278556U (en) | A kind of pressurized tank pump control unit based on motor speed | |
| CN110931311A (en) | VSP5 switch electric control circuit | |
| CN104466974A (en) | Combined type synchronous switch based on split-phase control technology | |
| CN220915178U (en) | Power plant security section 380V motor decompression self-starting system | |
| CN221328620U (en) | Starting grid-connected control circuit of camera |
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 | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210618 |