CN110021486B - Automatic reclosing device for voltage-loss tripping - Google Patents

Automatic reclosing device for voltage-loss tripping Download PDF

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Publication number
CN110021486B
CN110021486B CN201910180974.5A CN201910180974A CN110021486B CN 110021486 B CN110021486 B CN 110021486B CN 201910180974 A CN201910180974 A CN 201910180974A CN 110021486 B CN110021486 B CN 110021486B
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relay
time delay
delay relay
contact switch
voltage
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CN110021486A (en
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郭军
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H9/00—Details of switching devices, not covered by groups H01H1/00 - H01H7/00
    • H01H9/54—Circuit arrangements not adapted to a particular application of the switching device and for which no provision exists elsewhere
    • 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
    • H02H7/04—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 transformers
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/12—Circuit arrangements for ac mains or ac distribution networks for adjusting voltage in ac networks by changing a characteristic of the network load
    • H02J3/14—Circuit arrangements for ac mains or ac distribution networks for adjusting voltage in ac networks by changing a characteristic of the network load by switching loads on to, or off from, network, e.g. progressively balanced loading
    • 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
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/30—Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
    • Y02B70/3225—Demand response systems, e.g. load shedding, peak shaving
    • 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
    • Y04S20/00—Management or operation of end-user stationary applications or the last stages of power distribution; Controlling, monitoring or operating thereof
    • Y04S20/20—End-user application control systems
    • Y04S20/222—Demand response systems, e.g. load shedding, peak shaving

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Keying Circuit Devices (AREA)
  • Emergency Protection Circuit Devices (AREA)

Abstract

The invention provides a no-voltage tripping automatic reclosing device which is used for a power distribution system and is connected with a breaker of the power distribution system, wherein the breaker is connected with the breaker, the breaker comprises a closing button AK, the no-voltage tripping automatic reclosing device comprises an automatic closing circuit, and the automatic closing circuit comprises a time delay relay S1, a relay U2 and a time delay relay S2. The switching-on button AK, the contact switch S11 of the delay relay S1 and the contact switch U21 of the relay U2 form a series loop; the time delay relay S1 is normally open, and the coil of the time delay relay S1 is connected with the power supply side of the power distribution system; the time delay relay S2 is normally open, and the coil of the time delay relay S2 is connected with the load side of the power distribution system; the contact switch S21 of the time delay relay S2, the coil of the relay U2 and the load side of the power distribution system are connected in series; the relay U2 is normally closed; and when the power supply side is electrified, the power distribution system is automatically switched on through the no-voltage tripping automatic reclosing device.

Description

Automatic reclosing device for voltage-loss tripping
Technical Field
The invention relates to a voltage-loss tripping automatic reclosing device.
Background
In order to ensure stable operation of a system and safe and reliable operation of equipment, no-voltage tripping devices are installed on distribution transformers of a 10KV power distribution system, when the distribution system fails, the no-voltage tripping devices disconnect low-voltage loads of the distribution transformers, when the system recovers to be normal, power operators reach the distribution transformers with relevant no-voltage tripping positions and manually close the switches, short 10kV high-voltage power failure (fault power failure, grounding line selection and load switching) can cause large-area low-voltage user no-voltage power failure, a large number of personnel and vehicles are required to be put into the work of recovering low-voltage power supply, and the low-voltage user power supply cannot be rapidly and timely recovered.
Disclosure of Invention
The invention aims to solve the technical problems and provides a no-voltage tripping automatic reclosing device which is used for a power distribution system and is connected with a breaker of the power distribution system, wherein the breaker is connected with a closing button AK, the closing button AK is a common switch, when the power distribution system is powered on again after the no-voltage tripping device of the breaker is tripped, the closing button AK is pressed, a closing coil of the no-voltage tripping device is electrified to generate excitation, the closing switch in the closing coil is pushed, and then the power supply side and the load side of the power distribution system are communicated.
The no-voltage tripping automatic reclosing device comprises an automatic closing circuit, wherein the automatic closing circuit comprises a time delay relay S1, a relay U2 and a time delay relay S2.
The switching-on button AK, the contact switch S11 of the delay relay S1 and the contact switch U21 of the relay U2 form a series loop;
the time delay relay S1 is normally open, and the coil of the time delay relay S1 is connected with the power supply side of the power distribution system;
the time delay relay S2 is normally open, and the coil of the time delay relay S2 is connected with the load side of the power distribution system;
the contact switch S21 of the time delay relay S2, the coil of the relay U2 and the load side of the power distribution system are connected in series;
the relay U2 is normally closed;
when the power side circular telegram back, time delay relay S1 ' S coil is electrified and contact switch S11 is closed after the settlement time, series circuit UNICOM, closing button AK short circuit switch-on, the work of losing voltage trip gear circular telegram of circuit breaker, and then distribution system closes a floodgate, the power side with load side UNICOM, promptly the load side circular telegram, time delay relay S2 ' S coil is electrified and contact switch S21 is closed after the settlement time, relay U2 ' S coil circular telegram and contact switch U21 disconnection, the series circuit disconnection.
Optionally, in the series circuit, a resistor R1 is connected in series between the contact switch S11 of the delay relay S1 and the contact switch U21 of the relay U2, so as to prevent personnel and equipment from being damaged due to sudden change of control loop current.
Optionally, the automatic closing circuit includes a relay U1, and the contact switch U11 of the relay U1 is connected in series in the series circuit.
Optionally, the automatic closing circuit includes relays U1 and R1; the contact switch U11 of the relay U1 is connected in series in the series loop; the R1 is connected in series between the contact switch S11 of the time delay relay S1 and the contact switch U21 of the relay U2.
Optionally, after the delay relay S1 is powered on, the delay relay is set to be closed for 30 seconds to 8 minutes.
Optionally, after the delay relay S2 is powered on, the delay setting is closed for 0.1 second to 10 seconds.
Optionally, the transformer box body is directly adsorbed by the shell, the shell is provided with a powerful magnet, the installation is convenient, the installation only needs 5 minutes under the condition that power failure is not needed, the normal operation of equipment is not influenced, and the transformer box body can be installed at any position according to the condition of field equipment. The device is externally connected with a wiring clamp, so that the aluminum busbar in the box transformer substation can be conveniently installed.
Optionally, the switching-on button AK adopts an electric switching-on mode and a manual switching-on mode.
Optionally, a switch KK is arranged between the automatic closing circuit and the power supply side of the power distribution system, and the switch KK can be disconnected when the transformer is maintained at high voltage and low voltage, so that misoperation of the device is prevented.
Correspondingly, the no-voltage tripping automatic reclosing device combination comprises N no-voltage tripping automatic reclosing devices which are respectively arranged on N transformers, and the delay setting time of the delay relay S1 of the N no-voltage tripping automatic reclosing devices is staggered.
As can be seen from the above description of the present invention, compared with the prior art, the present invention has the following advantages:
the application provides a no-voltage tripping automatic reclosing device and combination thereof, no-voltage tripping automatic reclosing device can reclose automatically, the effectual personnel work efficiency that has improved prevents to have a power failure for a long time because of the low pressure user that personnel failed to arrive the scene combined floodgate for a long time and cause, and simultaneously, this device reclosing time limit is long, has 30 seconds to 8 minutes time delay setting, can make many transformers close a floodgate respectively, prevent that the excitation surge current of system combined floodgate is too big, the effectual system excitation surge current that has reduced harms equipment, the safe and reliable operation of system has been ensured.
Drawings
In order to more clearly illustrate the technical solution of the embodiment of the present invention, the drawings needed to be used in the embodiment will be briefly described below, and it is obvious to those skilled in the art that other drawings can be obtained according to the drawings without any creative effort.
Wherein:
FIG. 1 is a first wiring schematic diagram of a no-voltage tripping automatic reclosing device of the invention;
FIG. 2 is a second schematic diagram of the wiring of the no-voltage tripping automatic reclosing device of the invention;
fig. 3 is a first wiring schematic diagram of the no-voltage tripping automatic reclosing device in the box type transformer;
FIG. 4 is a second schematic diagram of the wiring of the no-voltage tripping automatic reclosing device in the box type transformer;
FIG. 5 is a table of the change of the current of the distribution transformer system (the voltage loss tripping device exits) when the cell is not installed;
fig. 6 is a table of the change of the current of the system (the automatic reclosing device of the no-voltage tripping device) of the distribution transformer switching system in the community when the community is installed.
Detailed Description
In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention clearer and clearer, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The first embodiment is as follows:
the utility model provides a no-voltage tripping automatic reclosing device for distribution system is connected with distribution system's circuit breaker, the circuit breaker is connected including closing button AK.
The voltage-loss tripping automatic reclosing device comprises an automatic closing circuit, wherein the automatic closing circuit comprises a relay U1, a time delay relay S1, a relay U2, a time delay relay S2, a resistor R1, a voltmeter V1 and a voltmeter V2.
As shown in fig. 1, the closing button AK, the contact switch U11 of the relay U1, the contact switch S11 of the delay relay S1, and the contact switch U21 of the relay U2 form a series circuit;
the time delay relay S1 is normally open, and a coil of the time delay relay S1 is connected with the power supply side of the power distribution system;
the time delay relay S2 is normally open, and the coil of the time delay relay S2 is connected with the load side of the power distribution system;
the contact switch S21 of the time delay relay S2, the coil of the relay U2 and the load side of the power distribution system are connected in series;
the relay U2 is normally closed;
referring to fig. 2, the relay U1, the delay relay S1, and the voltmeter V1 in the present embodiment are connected to the power supply side in parallel, and the voltmeter V1 displays the commercial power; the time delay relay S2 and the voltmeter V2 are connected in parallel to the load side. The automatic closing circuit with be equipped with switch KK between distribution system's the power supply side, but disconnection switch KK when transformer high, low pressure overhauls prevents the device malfunction.
As shown in fig. 3 and 4, when the power supply side is powered on, the coil of the relay U1 is charged and the contact switch U11 is closed, the coil of the time delay relay S1 is charged and the contact switch S11 is closed after a set time, the series circuit is connected, the closing button AK is short-circuited, the no-voltage tripping device of the circuit breaker is powered on to operate, and the distribution system is closed, the power supply side is connected with the load side, that is, the load side is powered on, the coil of the time delay relay S2 is charged and the contact switch S21 is closed after a set time, the coil of the relay U2 is powered on and the contact switch U21 is opened, and the series circuit is opened.
In this embodiment, after the delay relay S1 is powered on, the delay is set to be closed for 30 seconds to 8 minutes; and after the time delay relay S2 is electrified, the time delay relay S2 is closed within 0.1 second to 10 seconds.
Example two:
on the basis of the first embodiment, the no-voltage tripping automatic reclosing device comprises a shell, wherein the shell is provided with a powerful magnet, the installation is convenient, the transformer box body is directly adsorbed, the installation only needs 5 minutes under the condition that power failure is not needed, the normal operation of equipment is not influenced, and the device can be installed at any position according to the condition of field equipment. The device is externally connected with a wiring clamp, so that the aluminum busbar in the box transformer substation can be conveniently installed.
Example three:
correspondingly, the combination of the no-voltage tripping automatic reclosing device comprises N no-voltage tripping automatic reclosing devices, the N no-voltage tripping automatic reclosing devices are respectively installed on N transformers, the delay setting time of a delay relay S1 of the N no-voltage tripping automatic reclosing devices is staggered, the reclosing action of the N transformers is staggered, the damage of system excitation inrush current to equipment of a power distribution system is effectively reduced, and the safe and reliable operation of the system is ensured.
When the method is put into a distribution transformer of 630KVA of a community, reclosing action is reliable, effective reclosing can be realized in each delay time period, and the excitation inrush current of the system is obviously reduced through measurement.
Please refer to the following table of change of current meter when the cell is not installed with the present application and fig. 5 for the table of change of current of the distribution transformer system (exit of the voltage loss tripping device) of the cell:
Figure RE-GDA0002070927150000051
please refer to the following change table of the ammeter installed in the community (fig. 6) related to the change table of the current of the distribution transformer system (the automatic reclosing device of the no-voltage release device) in the community:
Figure RE-GDA0002070927150000052
it can obviously be seen through the comparison, when throwing into this application, and delay relay S1' S time delay settlement time sets up differently, can effectively reduce the excitation inrush current of system.
As can be seen from the above description of the present invention, compared with the prior art, the present invention has the following advantages:
the application provides a no-voltage tripping automatic reclosing device and combination thereof, no-voltage tripping automatic reclosing device can reclose automatically, the effectual personnel work efficiency that has improved prevents to have a power failure for a long time because of the low pressure user that personnel failed to arrive the scene combined floodgate for a long time and cause, and simultaneously, this device reclosing time limit is long, has 30 seconds to 8 minutes time delay setting, can make many transformers close a floodgate respectively, prevent that the excitation surge current of system combined floodgate is too big, the effectual system excitation surge current that has reduced harms equipment, the safe and reliable operation of system has been ensured.
It is to be noted that, in the present invention, relational terms such as "first" and "second", and the like, are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
The foregoing is merely a detailed description of embodiments of the invention that will enable those skilled in the art to understand or practice the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
It will be understood that the present application is not limited to what has been described above and shown in the accompanying drawings, and that various modifications and changes can be made without departing from the scope thereof. The scope of the application is limited only by the appended claims.

Claims (9)

1. A voltage-loss tripping automatic reclosing device is used for a power distribution system and is connected with a circuit breaker of the power distribution system, the circuit breaker is connected with a closing button AK, and the voltage-loss tripping automatic reclosing device is characterized by comprising an automatic closing circuit and a shell, wherein the automatic closing circuit comprises a time delay relay S1, a relay U2 and a time delay relay S2;
the switching-on button AK, the contact switch S11 of the delay relay S1 and the contact switch U21 of the relay U2 form a series loop;
the time delay relay S1 is normally open, and the coil of the time delay relay S1 is connected with the power supply side of the power distribution system;
the time delay relay S2 is normally open, and the coil of the time delay relay S2 is connected with the load side of the power distribution system;
the contact switch S21 of the time delay relay S2, the coil of the relay U2 and the load side of the power distribution system are connected in series;
the relay U2 is normally closed;
when the power supply side is electrified, a coil of the time delay relay S1 is electrified, a contact switch S11 is closed after set time, the series circuit is communicated, the closing button AK is in short circuit connection, a voltage loss tripping device of the circuit breaker is electrified to work, the power distribution system is closed, the power supply side is communicated with the load side, namely the load side is electrified, the coil of the time delay relay S2 is electrified, the contact switch S21 is closed after set time, the coil of the relay U2 is electrified, the contact switch U21 is disconnected, and the series circuit is disconnected;
the shell is provided with a powerful magnet; the device is externally connected with a wiring clamp.
2. The automatic reclosing device according to claim 1, wherein a resistor R1 is connected in series between the contact switch S11 of the delay relay S1 and the contact switch U21 of the relay U2 in the series circuit.
3. The under-voltage tripping automatic reclosing device according to claim 1, wherein the automatic closing circuit comprises a relay U1, and a contact switch U11 of the relay U1 is connected in series in the series circuit.
4. The under-voltage tripping automatic reclosing device according to claim 1, wherein the automatic closing circuit comprises relays U1 and R1; a contact switch U11 of the relay U1 is connected in series in the series circuit; the R1 is connected in series between the contact switch S11 of the time delay relay S1 and the contact switch U21 of the relay U2.
5. The under-voltage tripping automatic reclosing device according to claim 1, wherein after the time delay relay S1 is powered on, the time delay setting is closed for 30 seconds to 8 minutes.
6. The under-voltage tripping automatic reclosing device according to claim 1, wherein after the time delay relay S2 is energized, the time delay setting is closed for 0.1 second to 10 seconds.
7. The under-voltage tripping automatic reclosing device according to claim 1, wherein the closing button AK adopts an electric closing mode and a manual closing mode.
8. The under-voltage tripping automatic reclosing device according to claim 1, wherein a switch KK is arranged between the automatic closing circuit and a power supply side of the power distribution system.
9. A no-voltage tripping automatic reclosing device combination is characterized by comprising N no-voltage tripping automatic reclosing devices as claimed in any one of claims 1 to 8, wherein the N no-voltage tripping automatic reclosing devices are respectively installed on N transformers, and the delay setting time of delay relays S1 of the N no-voltage tripping automatic reclosing devices is staggered with each other.
CN201910180974.5A 2019-03-11 2019-03-11 Automatic reclosing device for voltage-loss tripping Expired - Fee Related CN110021486B (en)

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CN110412322B (en) * 2019-09-10 2024-03-19 广东电网有限责任公司 Secondary voltage switching device for station electric energy metering
CN111048328B (en) * 2020-01-14 2020-09-01 永康串行电子有限公司 Air electric switch capable of automatically closing

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KR100374988B1 (en) * 2001-04-20 2003-03-06 손석환 Automatic closing circuit of CB
CN103683176B (en) * 2013-12-06 2016-04-13 国家电网公司 Intelligent breaker auto recloser
CN204131081U (en) * 2014-10-27 2015-01-28 国家电网公司 A kind of automatic reclosing low-voltage circuit breaker
CN104638603A (en) * 2015-03-26 2015-05-20 青岛飞鹏能源有限公司 Automatic reclosing method and device for power recovery
CN206517031U (en) * 2017-03-16 2017-09-22 安德利集团有限公司 A kind of autoreclose breaker mechanism

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