CN110426595B - Ring network unit primary and secondary loop fault detection device - Google Patents
Ring network unit primary and secondary loop fault detection device Download PDFInfo
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- CN110426595B CN110426595B CN201910831853.2A CN201910831853A CN110426595B CN 110426595 B CN110426595 B CN 110426595B CN 201910831853 A CN201910831853 A CN 201910831853A CN 110426595 B CN110426595 B CN 110426595B
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- 238000001514 detection method Methods 0.000 title claims abstract description 37
- 238000012360 testing method Methods 0.000 claims abstract description 38
- 238000004804 winding Methods 0.000 claims description 4
- 238000002955 isolation Methods 0.000 abstract description 3
- 238000000034 method Methods 0.000 abstract description 3
- 230000004927 fusion Effects 0.000 abstract description 2
- 238000012423 maintenance Methods 0.000 description 8
- 238000010586 diagram Methods 0.000 description 5
- 238000005259 measurement Methods 0.000 description 3
- 238000003780 insertion Methods 0.000 description 2
- 230000037431 insertion Effects 0.000 description 2
- 239000004020 conductor Substances 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 230000011664 signaling Effects 0.000 description 1
Classifications
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
- Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
- Y04S10/00—Systems supporting electrical power generation, transmission or distribution
- Y04S10/50—Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
- Y04S10/52—Outage or fault management, e.g. fault detection or location
Landscapes
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
- Remote Monitoring And Control Of Power-Distribution Networks (AREA)
Abstract
The invention relates to a ring network unit-secondary circuit fault detection device which is characterized by comprising a plug-in wiring terminal seat, a working plug and a test plug, wherein the plug-in wiring terminal seat is arranged on a ring network box and consists of at least 11 terminals, each terminal of the terminal seat consists of an upper end and a lower end which can be connected or disconnected, and the test plug corresponds to the terminal seat and also consists of the upper end and the lower end which can be connected or disconnected. The invention solves the main technical problems of realizing the isolation and detection of a secondary circuit in a ring network unit system, and ensuring that the isolation and detection of an operation state of the secondary circuit can be realized under the condition of no power failure when fault detection is carried out, and judging the position of the fault on the spot; the method is high in universality and suitable for a secondary fusion system of all ring network units.
Description
Technical Field
The invention belongs to the technical field of electric loop fault detection, and particularly relates to a ring network unit-secondary loop fault detection device.
Background
At present, an indoor 10KV switching station and an outdoor 10KV ring main unit in a ring network power supply system are integrated with secondary equipment, and a 10KV ring main unit is added with a distribution network automation terminal (DTU) to realize three-remote control of remote control, remote measurement and remote signaling. Because the secondary three-remote system is added in the primary power distribution system, in the actual operation and maintenance, if the system fails, whether the system is a primary loop failure or a secondary loop failure must be judged first, and then an maintainer is sent to the failure site. And because the detection and maintenance of the primary and secondary circuits involve different professions such as strong electricity, weak points and the like, the detection and maintenance personnel who send out the profession become difficult. In reality, after a primary equipment detection maintenance person arrives at the site for detection, the primary loop is confirmed to be fault-free, and a secondary equipment detection maintenance person has to be dispatched to go to the site, so that the efficiency of maintenance work is greatly affected. In addition, the maintenance is carried out by power failure, and if the discrimination of the fault of a secondary circuit cannot be solved at one time, the number of times of power failure is increased, so that the stability of power supply is affected.
Disclosure of Invention
In order to solve the problems, the invention provides a ring network unit-secondary circuit fault detection device capable of distinguishing a secondary circuit fault at a time under the condition of no power failure.
The purpose of the invention is realized in the following way: a ring network unit-secondary circuit fault detection device is characterized by comprising a plug-in wiring terminal seat, a working plug and a test plug, wherein the plug-in wiring terminal seat is arranged on a ring network box and consists of at least 11 terminals, each terminal of the terminal seat consists of an upper end and a lower end which can be connected or disconnected, the test plug corresponds to the terminal seat and also consists of the upper end and the lower end which can be connected or disconnected, and the connection mode of the terminal seat and ring network box equipment is as follows:
A. the lower ends of terminals 1, 2, 3 and 4 of the terminal seat are connected to the secondary winding of the current transformer, and the upper ends of the terminals are connected to the DTU through current wiring terminals in the instrument room so as to form a secondary current loop;
B. the lower end of a No. 5 terminal of the terminal seat is connected to a DTU remote closing outlet, and the upper end of the terminal is connected in parallel to a breaker closing loop so as to form a remote closing loop;
C. the lower end of a No. 6 terminal of the test terminal seat is connected to one end of a KA1 relay coil, the other end of the relay coil is connected with a power zero line, and the upper end of the terminal is suspended, so that a detection circuit is formed;
D. the lower end of a No. 7 terminal of the terminal seat is connected to a DTU remote opening outlet, and the upper end of the terminal is connected in parallel to a breaker opening loop so as to form a remote opening loop;
E. the lower end of the No. 8 terminal of the terminal seat is connected to one end of the KA2 relay coil, the other end of the relay coil is connected with a power zero line, and the upper end of the terminal is suspended, so that a detection loop is formed;
F. the lower end of the No. 9 terminal of the terminal seat is connected to the DTU remote closing outlet loop in parallel, and the upper end of the terminal is suspended, so that a detection loop is formed;
G. the lower end of a No. 10 terminal of the terminal seat is connected to one end of auxiliary contacts of the KA1 and KA2 relays, the other ends of the auxiliary contacts of the KA1 and KA2 relays are respectively connected to one ends of relay coils corresponding to the KA1 and KA2 relays, and the upper ends of the terminals are suspended, so that a detection loop is formed;
H. the lower end of the 11 # terminal of the terminal seat is connected to one end of the KA2 relay auxiliary contact, and the upper end of the terminal is connected to the other end of the KA2 relay auxiliary contact, so that a standby detection loop is formed;
I. the coil loops of the relays KA1 and KA2 are respectively connected with an indicator lamp in parallel, and the indicator lamp is connected between the lower end of the No. 10 terminal of the terminal seat and the power zero line in series.
The terminal seat, at 1 to 10 terminal lower extreme, be provided with the short circuit ring respectively.
The test plug is provided with short-circuit rings at the lower ends of the No. 1 to No. 10 terminals corresponding to the terminals of the terminal seat.
The test plug is provided with binding posts at the upper end and the lower end of each terminal.
And aviation plugs are respectively arranged at the upper ends of the terminals 1, 2, 3 and 4 of the terminal seat through the connection sections of the current wiring terminals and the DTU in the instrument room.
The invention solves the main technical problems of realizing the isolation and detection of a secondary loop in a ring network unit system, and has the advantages that: based on the unique structures of the test terminal seat and the test plug and the matched circuit design, the secondary circuit can be isolated and the operation state can be detected under the condition of no power failure when the fault is detected, and the position of the fault can be judged on site; the method is high in universality and suitable for a secondary fusion system of all ring network units.
Drawings
FIG. 1 is a schematic circuit diagram of the present invention;
FIG. 2 is a sectional view showing the internal structure of the terminal block of the present invention;
FIG. 3 is a circuit diagram of the terminal block working plug insertion state of the present invention;
fig. 4 is a drawing showing the state of the terminal block working plug of the present invention;
FIG. 5 is a circuit diagram of the state of FIG. 4;
FIG. 6 is a diagram showing the state of insertion of a test plug for testing a terminal block according to the present invention;
FIG. 7 is a circuit diagram of the state of FIG. 6;
fig. 8 is a sectional view showing the internal structure of the test plug of the present invention.
Detailed Description
The invention is further described below with reference to the accompanying drawings:
as shown in FIG. 1, the test terminal block arranged on the cabinet door of the ring main unit in the embodiment has 11 terminals, and each terminal consists of an upper end and a lower end which can be communicated or isolated.
The lower ends of terminals 1, 2, 3 and 4 of the terminal seat are connected with the secondary winding of the current transformer, and the upper ends of the terminals are connected to the DTU through the current wiring terminal and the aviation plug in the instrument room. The secondary current loop is formed by the method, wherein the terminals 1, 2, 3 and 4 play a role in conducting and providing interfaces for external detection equipment, the current terminal in the instrument room plays a role in conducting, and the secondary winding of the current transformer converts the primary current value into the secondary current value. The DTU current acquisition unit is a measurement unit and provides data for DTU protection logic operation.
The lower end of a No. 5 terminal of the terminal seat is connected to a DTU remote closing outlet, and the upper end of the terminal is connected in parallel to a breaker closing loop. The connection forms a remote control closing loop, and plays roles in conducting and isolating the remote control closing loop.
The 6 number terminal lower extreme of terminal seat is connected to KA1 relay coil's one end, and relay coil's the other end is connected with power zero line, and the terminal upper end is unsettled. The connection forms a detection circuit, and after the closing loop is isolated, the conduction condition of the DTU remote control closing loop is detected.
The lower end of the No. 7 terminal of the terminal seat is connected to the DTU remote-control outlet, and the upper end of the terminal is connected in parallel to the breaker opening loop. The connection forms a remote control opening loop, and plays a role in conducting and isolating the remote control opening loop.
The No. 8 terminal lower extreme of terminal seat is connected to KA2 relay coil's one end, and relay coil's the other end is connected with power zero line, and the terminal upper end is unsettled. The connection forms a detection circuit, and after the closing loop is isolated, the conduction condition of the DTU remote control closing loop is detected.
The lower end of the No. 9 terminal of the terminal seat is connected to the DTU remote-closing outlet loop in parallel, and the upper end of the terminal is suspended. The connection forms a detection circuit, and after the separation of the brake-separating loop, the conduction condition of the DTU remote control brake-separating loop is detected.
The 10 number terminal lower extreme of terminal seat is connected to KA1 and KA2 relay auxiliary contact (normally open point's one end, and KA1 and KA2 relay auxiliary contact's the other end is connected to the one end that corresponds KA1 and KA2 relay coil respectively, and the terminal upper end is unsettled. The connection and the circuit formed by terminals 8 and 9 jointly realize detection of the conduction condition of the DTU remote control switching-on loop and the switching-off loop.
The 11 # terminal lower extreme of terminal seat is connected to KA2 relay auxiliary contact's one end, and the terminal upper end is connected to KA2 relay auxiliary contact's the other end. This connection constitutes a backup detection loop providing a backup protection trip backup time detection point.
The terminal seat is provided with the short circuit ring 1 through the terminal lower extreme of 10 numbers.
Fig. 2 shows a structure of the terminal block when the working plug and the test plug are not inserted, and the upper and lower ends of the terminal are normally open. The lower end of the terminal is provided with a shorting ring 1. The upper and lower ends of the terminal are respectively provided with a wiring point 2 and a wiring point 3 which are connected with corresponding circuits.
As shown in fig. 1 and 3, in daily operation, the working plug is inserted into the terminal seat, the upper end and the lower end of the terminal are conducted by the conductors on the plug, the short circuit ring 1 at the lower end of the terminal is invalid, the KA1 and KA2 relays, the HR1, HR2 and HG indicator lamps do not work, the test loop and the control loop are separated, and one secondary loop is in a normal working state.
As shown in fig. 2, 4 and 5, when the working plug is pulled out, the upper end and the lower end of the terminal seat are disconnected, and the short circuit ring 1 at the lower end of the terminal takes effect, wherein the lower ends of the terminals 1, 2, 3 and 4 are in short circuit, and a protection current loop is sealed; 5. the lower end of the No. 6 terminal is short-circuited, and a remote control switching-on circuit is switched to a KA1 coil by a switching-on coil of the circuit breaker; 7. the lower end of the No. 8 terminal is short-circuited, and a remote control tripping circuit is switched to a KA2 coil by a tripping coil of the circuit breaker; 9. the lower end of the No. 10 terminal is short-circuited, and remote control is used for indicating the opening and closing power supply.
As shown in fig. 6 and 7, when fault detection is required, the terminal block working plug is pulled out and the test plug is inserted. At this time, the upper and lower ends of the terminal block terminal are disconnected, and the shorting ring at the lower end of the terminal is ineffective. The short circuit ring at the lower end of the test plug takes effect, so that the lower ends of the terminals 1, 2, 3 and 4 are in short circuit, and the current loop is protected to be sealed; adding an overcurrent signal to the DTU at the upper end of the test plug; the lower ends of the terminals 7 and 8 of the test plug are short-circuited, and a remote control tripping circuit is switched to a KA2 coil by a tripping coil of the circuit breaker; receiving an overcurrent signal at the DTU, sending an overcurrent remote control tripping signal, and enabling the intermediate relay KA2 to act; the passive opening point of the intermediate relay KA2 is closed, and the intermediate relay KA2 can be detected by conducting the test plug No. 11 terminal up and down.
As shown in fig. 8, the test plug is provided with terminals consisting of upper and lower ends corresponding to the terminal block, and the upper and lower ends of each terminal are provided with a binding post 4 for connecting with the detecting device. The terminal is provided with a shorting ring 5.
After the test is finished, the working change-over switch is reset when being driven to the local position, then the trip time can be tested again when being driven to the remote place, the test plug is pulled out, then the working plug is inserted, the self-locking and experimental loop can be released, and the normal working state is recovered.
Under the condition that the system normally operates, the background can monitor the current value of the current system in real time, and when an operation and maintenance person sends out that the three-phase current value of the power grid is unbalanced, the current value of the current system can be a problem of primary equipment (such as a current transformer) or a problem of a secondary ammeter or a problem of a detection system. At the moment, the working plug of the test terminal seat can be pulled out, the short circuit ring at the lower end of the terminal block takes effect, the secondary current loop is short-circuited, and overvoltage is prevented from being generated by the secondary loop of the current transformer in an open circuit. The test plug is then inserted into the test terminal block. At this time, the short circuit ring at the lower end of the terminal of the test terminal seat is invalid, and the short circuit ring on the test plug takes effect instead of the short circuit ring of the test terminal seat of the cabinet door functionally. Meanwhile, the upper end and the lower end of the terminal of the test terminal seat are disconnected, and the test terminal seat is separated from the system measuring device. At this time, the detection equipment is connected to the binding post B of the test plug, and then the short circuit ring on the test plug is correspondingly removed, so that the function of detecting the current value of the system is realized. If the three-phase current is balanced and the value reaches the standard, the primary equipment is proved to be free of problems, and the problems are solved on secondary measurement equipment on the system.
Examples: when the circuit breaker cannot realize remote switching-on, the situation is that a switching-on signal of the DTU is not given, and the switching-on coil of the circuit breaker is damaged. The working plug of test terminal seat on the cabinet door can be pulled out at this moment, and the short circuit ring of test terminal seat takes effect at this moment, separates the closing circuit of DTU switching-on export return circuit and circuit breaker, detects return circuit and DTU switching-on return circuit intercommunication simultaneously, and operation DTU, DTU switching-on export action at this moment, if red light HR1 is bright, proves that DTU switching-on export return circuit does not have the problem, and the problem appears on circuit breaker switching-on coil.
Claims (3)
1. A ring network unit-secondary circuit fault detection device is characterized by comprising a plug-in wiring terminal seat, a working plug and a test plug, wherein the plug-in wiring terminal seat is arranged on a ring network box and consists of at least 11 terminals, each terminal of the terminal seat consists of an upper end and a lower end which can be connected or disconnected, the test plug corresponds to the terminal seat and also consists of the upper end and the lower end which can be connected or disconnected, and the connection mode of the terminal seat and ring network box equipment is as follows:
A. the lower ends of terminals 1, 2, 3 and 4 of the terminal seat are connected to the secondary winding of the current transformer, and the upper ends of the terminals are connected to the DTU through current wiring terminals in the instrument room so as to form a secondary current loop;
B. the lower end of a No. 5 terminal of the terminal seat is connected to a DTU remote closing outlet, and the upper end of the terminal is connected in parallel to a breaker closing loop so as to form a remote closing loop;
C. the lower end of a No. 6 terminal of the test terminal seat is connected to one end of a KA1 relay coil, the other end of the relay coil is connected with a power zero line, and the upper end of the terminal is suspended, so that a detection circuit is formed;
D. the lower end of a No. 7 terminal of the terminal seat is connected to a DTU remote opening outlet, and the upper end of the terminal is connected in parallel to a breaker opening loop so as to form a remote opening loop;
E. the lower end of the No. 8 terminal of the terminal seat is connected to one end of the KA2 relay coil, the other end of the relay coil is connected with a power zero line, and the upper end of the terminal is suspended, so that a detection loop is formed;
F. the lower end of the No. 9 terminal of the terminal seat is connected to the DTU remote closing outlet loop in parallel, and the upper end of the terminal is suspended, so that a detection loop is formed;
G. the lower end of a No. 10 terminal of the terminal seat is connected to one end of auxiliary contacts of the KA1 and KA2 relays, the other ends of the auxiliary contacts of the KA1 and KA2 relays are respectively connected to one ends of relay coils corresponding to the KA1 and KA2 relays, and the upper ends of the terminals are suspended, so that a detection loop is formed;
H. the lower end of the 11 # terminal of the terminal seat is connected to one end of the KA2 relay auxiliary contact, and the upper end of the terminal is connected to the other end of the KA2 relay auxiliary contact, so that a standby detection loop is formed;
I. the coil loops of the relays KA1 and KA2 are respectively connected with an indicator lamp in parallel, and the indicator lamp is connected between the lower end of the No. 10 terminal of the terminal seat and a power zero line in series;
J. short-circuit rings are respectively arranged at the lower ends of the terminals 1 to 10 corresponding to the terminals of the terminal seat;
K. binding posts are arranged at the upper end and the lower end of each terminal.
2. The device for detecting a secondary loop fault of a ring main unit according to claim 1, wherein the terminal blocks are respectively provided with shorting rings at the lower ends of the terminals 1 to 10.
3. The device for detecting the faults of the secondary circuit of the ring main unit according to claim 1, wherein aviation plugs are respectively arranged at the upper ends of terminals 1, 2, 3 and 4 of the terminal base through connection sections of current wiring terminals and DTUs in an instrument room.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910831853.2A CN110426595B (en) | 2019-09-04 | 2019-09-04 | Ring network unit primary and secondary loop fault detection device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910831853.2A CN110426595B (en) | 2019-09-04 | 2019-09-04 | Ring network unit primary and secondary loop fault detection device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110426595A CN110426595A (en) | 2019-11-08 |
| CN110426595B true CN110426595B (en) | 2024-03-29 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201910831853.2A Active CN110426595B (en) | 2019-09-04 | 2019-09-04 | Ring network unit primary and secondary loop fault detection device |
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| Country | Link |
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Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115327284B (en) * | 2022-10-13 | 2023-04-07 | 江苏大烨智能电气股份有限公司 | Standardized looped network box multifunctional test tool and use method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB794370A (en) * | 1954-11-29 | 1958-04-30 | Gen Electric | Improvements in and relating to protective systems for electric transmission lines |
| US4864285A (en) * | 1988-05-11 | 1989-09-05 | O G & E | Method and apparatus for testing contacts to determine if opened or closed |
| JPH0923565A (en) * | 1995-07-07 | 1997-01-21 | Toshiba Corp | Monitoring circuit of protective relay device |
| CN103454549A (en) * | 2013-09-18 | 2013-12-18 | 福州大学 | Early detection, recognition and line determination method for short circuit faults of looped network power distribution system |
| CN204835232U (en) * | 2015-06-16 | 2015-12-02 | 国网山东省电力公司济南供电公司 | Looped netowrk cabinet secondary circuit stator indicator |
| CN107884707A (en) * | 2017-09-30 | 2018-04-06 | 杨启蓓 | High-voltage circuit-breaker switching on-off time on-Line Monitor Device and method |
-
2019
- 2019-09-04 CN CN201910831853.2A patent/CN110426595B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB794370A (en) * | 1954-11-29 | 1958-04-30 | Gen Electric | Improvements in and relating to protective systems for electric transmission lines |
| US4864285A (en) * | 1988-05-11 | 1989-09-05 | O G & E | Method and apparatus for testing contacts to determine if opened or closed |
| JPH0923565A (en) * | 1995-07-07 | 1997-01-21 | Toshiba Corp | Monitoring circuit of protective relay device |
| CN103454549A (en) * | 2013-09-18 | 2013-12-18 | 福州大学 | Early detection, recognition and line determination method for short circuit faults of looped network power distribution system |
| CN204835232U (en) * | 2015-06-16 | 2015-12-02 | 国网山东省电力公司济南供电公司 | Looped netowrk cabinet secondary circuit stator indicator |
| CN107884707A (en) * | 2017-09-30 | 2018-04-06 | 杨启蓓 | High-voltage circuit-breaker switching on-off time on-Line Monitor Device and method |
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| CN110426595A (en) | 2019-11-08 |
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