CN208571574U - Low-voltage platform area neutral point drifting protective device - Google Patents

Low-voltage platform area neutral point drifting protective device Download PDF

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Publication number
CN208571574U
CN208571574U CN201821030570.5U CN201821030570U CN208571574U CN 208571574 U CN208571574 U CN 208571574U CN 201821030570 U CN201821030570 U CN 201821030570U CN 208571574 U CN208571574 U CN 208571574U
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China
Prior art keywords
unit
voltage
over
under
contactor
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CN201821030570.5U
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Chinese (zh)
Inventor
王斌
陈韶昱
徐益飞
刘庆节
郑利宏
方旭
刘金明
李苏华
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
State Grid Corp of China SGCC
Quzhou Power Supply Co of State Grid Zhejiang Electric Power Co Ltd
Changshan Power Supply Co of State Grid Zhejiang Electric Power Co Ltd
Original Assignee
State Grid Corp of China SGCC
Quzhou Power Supply Co of State Grid Zhejiang Electric Power Co Ltd
Changshan Power Supply Co of State Grid Zhejiang Electric Power Co Ltd
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Application filed by State Grid Corp of China SGCC, Quzhou Power Supply Co of State Grid Zhejiang Electric Power Co Ltd, Changshan Power Supply Co of State Grid Zhejiang Electric Power Co Ltd filed Critical State Grid Corp of China SGCC
Priority to CN201821030570.5U priority Critical patent/CN208571574U/en
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    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • YGENERAL 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
    • Y04INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
    • Y04SSYSTEMS 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
    • Y04S10/00Systems supporting electrical power generation, transmission or distribution
    • Y04S10/20Systems supporting electrical power generation, transmission or distribution using protection elements, arrangements or systems

Abstract

The utility model discloses low-voltage platform area neutral point drifting protective devices.The problem of the problem of solving neutral point drifting leads to overvoltage, causes various failures, and structure is complicated for existing neutral point protecting device, cannot remind operator in time.Device includes input unit, output unit, under-voltage/over-voltage protection unit, compensating unit, alarm unit, switch unit; input unit connects three phase network; input unit is connected with under-voltage/over-voltage protection unit, compensating unit, alarm unit respectively; compensating unit is grounded after passing through connection switch unit; under-voltage/over-voltage protection unit and alarm unit after connection switch unit with output unit by connecting, output unit and power distribution room connection.The utility model can the neutral point drifting unusual condition to three phase network detect; and protection signal is generated according to unusual condition, control distributor disconnects work, is protected to the load of connection; it can also be alarmed simultaneously according to unusual condition, remind user in time.

Description

Low-voltage platform area neutral point drifting protective device
Technical field
The utility model relates to a kind of voltage protection technical fields, protect more particularly, to a kind of low-voltage platform area neutral point drifting Protection unit.
Background technique
After three-phase and four-line power supply system zero curve disconnects, due to the imbalance of threephase load, lead to neutral point drifting.Zero curve is disconnected Afterwards, former 220V electrical appliance only constitutes circuit by other phase lines without zero curve, and any two-phase phase voltage is 380V, thus tight Weight overvoltage causes various failures.Current existing neutral point drifting protective device circuit structure is more complicated, and cannot be timely It is alarmed to remind operator.
Summary of the invention
The utility model, which mainly solves neutral point drifting in the prior art, leads to overvoltage, causes various failures, and The problem of the problem of structure is complicated for existing neutral point protecting device, cannot remind operator in time, provide a kind of low-voltage platform Area's neutral point drifting protective device.
Above technical problems of the utility model are mainly solved by the following technical scheme: a kind of low-voltage platform area Neutral point drifting protective device, it is characterised in that: including input unit, output unit, the deficient over-voltage protected to deficient over-voltage Protection location owes the alarm unit that over-voltage is alarmed according to the compensating unit of deficient over-voltage generation distributor protection signal, basis, And the switch unit of control compensating unit, alarm unit work, the input unit connect three phase network, input unit difference It is connected with under-voltage/over-voltage protection unit, compensating unit, alarm unit, compensating unit is grounded after passing through connection switch unit, owes over-voltage Protection location and alarm unit after connection switch unit with output unit by connecting, output unit and power distribution room connection. The utility model can the neutral point drifting unusual condition to three phase network detect, and according to unusual condition generate protection letter Number, control distributor disconnects work, the load of connection protected, while can also be alarmed according to unusual condition, and When remind user.Wherein under-voltage/over-voltage protection unit is for detecting three-phase electricity voltage condition, when certain one-phase circuit is owed When overpressure situation, protected by disconnecting circuit.Compensating unit is generated when overpressure conditions occurs owing in any phase of three-phase electricity Signal is protected, protection signal reaches distributor, load of the distributor according to protection signal disconnecting circuit, to connection by output end It is protected.Alarm unit occurs owing alarming under overpressure situation in circuit, and sends warning message to user.Switch unit It is opened and closed according to the state of under-voltage/over-voltage protection unit, controls compensating unit and alarm unit work.
As a preferred embodiment, the input unit includes three input terminals being electrically connected respectively with three-phase, Yi Jilian The three-phase breaker QF2 on three input ports is met, the output unit includes zero line output end and connection zero line output end Single-phase circuit breaker QF1, the under-voltage/over-voltage protection unit includes that under-voltage/over-voltage protection device U1, under-voltage/over-voltage protection device U2 and deficient over-voltage are protected Device U3 is protected, each under-voltage/over-voltage protection device input terminal is connected respectively three output ends of three-phase breaker QF2, and the switch is single Member includes contactor KM1, contactor KM2 and contactor KM3, and contactor KM1, contactor KM2, contactor KM3 respectively include line Enclose KM11, coil KM21, coil KM31, under-voltage/over-voltage protection device U1, under-voltage/over-voltage protection device U2, under-voltage/over-voltage protection device U3 output end point It Lian Jie not be connected on the single-phase circuit breaker QF1 of output unit after coil KM11, coil KM21, coil KM31.Output unit Zero line output end is connect by cable with power distribution room branched line.Three input terminals of input unit are electrically connected with three-phase respectively. Under-voltage/over-voltage protection device disconnects protecting circuit when circuit sends and owes over-voltage.The coil of contactor respectively with corresponding overvoltage protection Device is cascaded, and when overvoltage protector disconnects, contactor power loss stops working, and benefit is controlled by the change of contacts status Repay the work of unit and alarm unit.
As a preferred embodiment, the compensating unit includes single-phase circuit breaker QF3, single-phase circuit breaker QF4, single-phase open circuit Device QF5, resistance R1, resistance R2, resistance R3, the contactor KM1, contactor KM2, contactor KM3 respectively include normally-closed contact KM12, normally-closed contact KM22, normally-closed contact KM32 are connected to after normally-closed contact KM12, single-phase circuit breaker QF3, resistance R1 series connection Between under-voltage/over-voltage protection device U1 input terminal and ground wire, it is connected to after normally-closed contact KM22, single-phase circuit breaker QF4, resistance R2 series connection Between under-voltage/over-voltage protection device U2 input terminal and ground wire, it is connected to after normally-closed contact KM32, single-phase circuit breaker QF5, resistance R3 series connection Between under-voltage/over-voltage protection device U3 input terminal and ground wire.Compensating unit gives power distribution room end according to generation signal the case where under-voltage.When When under-voltage situation occurs for a certain phase line, the protection location of the corresponding route cuts off circuit, the corresponding normally closed touching of switch unit Point closes the switch, so that circuit is connected all the way in compensating unit, electric current is by breaker and is electronically connected to 1.5- on the earth field 2.5A leakage current, the current feedback to power distribution room force power distribution room residual current operated protective device to trip, play a protective role.
As a preferred embodiment, the alarm unit includes handset warner and loudspeaker, and the handset warner is just The connection of one output end of pole input terminal and input unit, the negative input of handset warner connects output unit, described to connect Tentaculum KM1, contactor KM2, contactor KM3 respectively include normally opened contact KM13, normally opened contact KM23, normally opened contact KM33, often The cathode output end and cathode of handset warner are connected to after opening contact KM13, normally opened contact KM23 and normally opened contact KM33 series connection Between output end, the signal output end of handset warner connects loudspeaker.Handset warner and the normally opened touching of each contactor in this programme Point constitutes a circuit, and in normal state, each reception centre device normally opened contact closure, handset warner receives signal at this time Without alarm, when occurring to owe over-voltage, when there is contactor to stop working, normally opened contact is in off-state, and circuit is broken It opens, the input signal on handset warner changes at this time, and handset warner generates alarm signal, is alarmed by loudspeaker.
As a preferred embodiment, including cabinet, insulation board is provided in cabinet, the under-voltage/over-voltage protection unit is mended It repays unit, switch unit and passes through guide rail respectively and be mounted on insulation board.
As a preferred embodiment, including cabinet, the alarm unit are mounted in cabinet or are mounted in power distribution room.Report Alert unit is mounted on device box end or power distribution room end according to demand, plays the function of reminding in time staff.
It as a preferred embodiment, further include communication unit, the communication unit is connected with handset warner, communication unit It is connect by network with remote user end.Handset warner passes through network by communication unit after generating alarm signal Alarm signal is sent to remote user end, operator is reminded, so that operator at the scene also can not be timely Solve situation.Communication unit is network access device, is connect by cable with handset warner.
Therefore, the utility model has the advantages that: can the neutral point drifting unusual condition to three phase network detect, and Protection signal is generated according to unusual condition, control distributor disconnects work, protected to the load of connection, while can also root It alarms according to unusual condition, reminds user in time.
Detailed description of the invention
Attached drawing 1 is a kind of structural frames diagram of the utility model;
Attached drawing 2 is a kind of electrical block diagram of the utility model.
1- input unit 2- compensating unit 3- under-voltage/over-voltage protection unit 4- alarm unit 5- switch unit 6- Output unit 7- power distribution room 8- handset warner 9- loudspeaker 10- communication unit.
Specific embodiment
Below with reference to the embodiments and with reference to the accompanying drawing the technical solutions of the present invention will be further described.
Embodiment:
A kind of low-voltage platform area neutral point drifting protective device of the present embodiment, as shown in Figure 1, including input unit 1, output list Member 6, under-voltage/over-voltage protection unit 3, the deficient over-voltage generation distributor of basis protected to deficient over-voltage protect the compensating unit of signal 2, the alarm unit 4 alarmed according to over-voltage is owed, and the switch unit 5 of control compensating unit, alarm unit work.Input Unit connects three phase network, and input unit is connected with under-voltage/over-voltage protection unit, compensating unit, alarm unit respectively, compensating unit By being grounded after connection switch unit, under-voltage/over-voltage protection unit and alarm unit after connection switch unit with output unit by connecting It connects, output unit and power distribution room connection.
As shown in Fig. 2, input unit includes three the input terminal A being electrically connected respectively with three-phase, input terminal B, input terminal C, And it is connected to the three-phase breaker QF2 on three input terminals.Output unit includes zero line output end N and connection zero line output end The single-phase circuit breaker QF1 of N.
Under-voltage/over-voltage protection unit includes under-voltage/over-voltage protection device U1, under-voltage/over-voltage protection device U2 and under-voltage/over-voltage protection device U3, is owed Pressure protector U1 input terminal is connect with the A circuitry phase output end of three-phase breaker QF2, under-voltage/over-voltage protection device U2 input terminal and three-phase The B circuitry phase output end of circuit breaker Q F2 connects, and the C circuitry phase of under-voltage/over-voltage protection device U3 input terminal and three-phase breaker QF2 export End connection.
Switch unit includes contactor KM1, contactor KM2 and contactor KM3, contactor KM1, contactor KM2, contactor KM3 respectively includes coil KM11, coil KM21, coil KM31, normally-closed contact KM11, normally-closed contact KM21, normally-closed contact KM31, And normally opened contact KM12, normally opened contact KM22, normally opened contact KM32.Wherein under-voltage/over-voltage protection device U1, under-voltage/over-voltage protection device U2, Under-voltage/over-voltage protection device U3 output end is connected to the single-phase of output unit after being separately connected coil KM11, coil KM21, coil KM31 On circuit breaker Q F1.
Compensating unit include single-phase circuit breaker QF3, single-phase circuit breaker QF4, single-phase circuit breaker QF5, resistance R1, resistance R2, Resistance R3.Under-voltage/over-voltage protection device U1 input terminal and ground are connected to after normally-closed contact KM12, single-phase circuit breaker QF3, resistance R1 series connection Between line, under-voltage/over-voltage protection device U2 input terminal and ground are connected to after normally-closed contact KM22, single-phase circuit breaker QF4, resistance R2 series connection Between line, under-voltage/over-voltage protection device U3 input terminal and ground are connected to after normally-closed contact KM32, single-phase circuit breaker QF5, resistance R3 series connection Between line.
Alarm unit includes handset warner 8, loudspeaker 9 and communication unit 10, the electrode input end of handset warner with it is defeated Enter the C phase output terminal connection of the three-phase breaker QF2 of unit, the negative input of handset warner connects the single-phase of output unit Circuit breaker Q F1 input terminal.Handset warner is connected to after normally opened contact KM13, normally opened contact KM23 and normally opened contact KM33 series connection Cathode output end and cathode output end between, the signal output end of handset warner connection loudspeaker and communication unit, communication is single Member is connect by network with remote user end, which is mobile phone or computer.
Device includes cabinet, and insulation board, under-voltage/over-voltage protection unit, compensating unit, switch unit difference are provided in cabinet It is mounted on insulation board by guide rail.Alarm unit is mounted in cabinet or is mounted in power distribution room.
At work, under normal circumstances, A phase, B phase, C phase voltage works normally, under-voltage/over-voltage protection device U1, U2, U3 conducting, Then coil KM11, KM21, KM31 be powered, normally-closed contact KM12, normally-closed contact KM22, normally-closed contact KM32 open, electric current without Resistance R1, resistance R2, resistance R3 ground connection are crossed, normally opened contact KM13, normally opened contact KM23, normally opened contact KM33 are not acted, Handset warner does not generate alarm signal.
If occurring to owe overpressure situation, the present embodiment is by taking A phase voltage occurs to owe over-voltage as an example, when A phase voltage is lower than 170V or be higher than 270V when, corresponding under-voltage/over-voltage protection device U1 cuts off the power, then KM11 power loss early period of contactor KM1, Normally closed opposite bank KM12 saves closure, and A phase current is connected to ground after flowing through normally-closed contact KM11, single-phase circuit breaker QF3, resistance R1, 1.5-2.5A leakage current is generated, power distribution room is transmitted to by output end, so that power distribution room residual current operated protective device trips, thus disconnected Switch power supply plays neutral point drifting protection.Normally opened contact KM13 is remained open simultaneously, handset warner circuit is disconnected, so that defeated The signal for entering handset warner changes, and handset warner generates warning message, and loudspeaker receive alarm signal and alarm, Alarm signal is occurred by network to remote user end communication unit.Any one phase of A phase, B phase, C phase or colleague occur low In 170V or be higher than 270V the case where, working principle is all identical.
The specific embodiments described herein are merely examples of the spirit of the present invention.The utility model institute Belonging to those skilled in the art can make various modifications or additions to the described embodiments or using similar Mode substitute, but without departing from the spirit of the present application or beyond the scope of the appended claims.
Although it is single that input unit, compensating unit, under-voltage/over-voltage protection unit, alarm unit, switch is used more herein The terms such as member, but it does not exclude the possibility of using other terms.The use of these items is only for more easily describing and Explain the essence of the utility model;Being construed as any additional limitation is disagreed with the spirit of the present invention 's.

Claims (7)

1. a kind of low-voltage platform area neutral point drifting protective device, it is characterised in that: including input unit, output unit, to owing The under-voltage/over-voltage protection unit protected, basis is pressed to owe the compensating unit of over-voltage generation distributor protection signal, according to deficient over-voltage The alarm unit alarmed, and the switch unit of control compensating unit, alarm unit work, the input unit connection three Phase power grid, input unit are connected with under-voltage/over-voltage protection unit, compensating unit, alarm unit respectively, and compensating unit is opened by connection It is grounded after closing unit, by connecting after connection switch unit with output unit, output is single for under-voltage/over-voltage protection unit and alarm unit Member and power distribution room connection.
2. neutral point drifting protective device in low-voltage platform area according to claim 1, it is characterized in that the input unit includes Three input terminals being electrically connected respectively with three-phase, and the three-phase breaker QF2 being connected on three input ports, the output Unit includes the single-phase circuit breaker QF1 at zero line output end and connection zero line output end, and the under-voltage/over-voltage protection unit includes owing Pressure protector U1, under-voltage/over-voltage protection device U2 and under-voltage/over-voltage protection device U3, each under-voltage/over-voltage protection device input terminal are connected respectively Three output ends of three-phase breaker QF2, the switch unit include contactor KM1, contactor KM2 and contactor KM3, contact Device KM1, contactor KM2, contactor KM3 respectively include coil KM11, coil KM21, coil KM31, under-voltage/over-voltage protection device U1, owe Overvoltage protector U2, under-voltage/over-voltage protection device U3 output end be separately connected after coil KM11, coil KM21, coil KM31 be connected to it is defeated Out on the single-phase circuit breaker QF1 of unit.
3. neutral point drifting protective device in low-voltage platform area according to claim 2, it is characterized in that the compensating unit includes Single-phase circuit breaker QF3, single-phase circuit breaker QF4, single-phase circuit breaker QF5, resistance R1, resistance R2, resistance R3, the contactor KM1, Contactor KM2, contactor KM3 respectively include normally-closed contact KM12, normally-closed contact KM22, normally-closed contact KM32, normally-closed contact It is connected between under-voltage/over-voltage protection device U1 input terminal and ground wire after KM12, single-phase circuit breaker QF3, resistance R1 series connection, normally-closed contact It is connected between under-voltage/over-voltage protection device U2 input terminal and ground wire after KM22, single-phase circuit breaker QF4, resistance R2 series connection, normally-closed contact It is connected between under-voltage/over-voltage protection device U3 input terminal and ground wire after KM32, single-phase circuit breaker QF5, resistance R3 series connection.
4. neutral point drifting protective device in low-voltage platform area according to claim 2, it is characterized in that the alarm unit includes Handset warner and loudspeaker, the electrode input end of the handset warner and an output end of input unit connect, mobile phone newspaper The negative input of alert device connects output unit, and the contactor KM1, contactor KM2, contactor KM3 respectively include normally opened touching Point KM13, normally opened contact KM23, normally opened contact KM33, normally opened contact KM13, normally opened contact KM23 and normally opened contact KM33 series connection It is connected between the cathode output end of handset warner and cathode output end afterwards, the signal output end of handset warner connects loudspeaker ?.
5. neutral point drifting protective device in low-voltage platform area according to claim 1 or 2 or 3, it is characterized in that include cabinet, Insulation board is provided in cabinet, the under-voltage/over-voltage protection unit, compensating unit, switch unit pass through guide rail respectively and be mounted on insulation On plate.
6. low-voltage platform area neutral point drifting protective device according to claim 1 or 2 or 4, it is characterized in that including cabinet, institute Alarm unit is stated to be mounted in cabinet or be mounted in power distribution room.
7. neutral point drifting protective device in low-voltage platform area according to claim 5, it is characterized in that further include communication unit, institute It states communication unit to be connected with handset warner, communication unit is connect by network with remote user end.
CN201821030570.5U 2018-06-29 2018-06-29 Low-voltage platform area neutral point drifting protective device Active CN208571574U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201821030570.5U CN208571574U (en) 2018-06-29 2018-06-29 Low-voltage platform area neutral point drifting protective device

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Application Number Priority Date Filing Date Title
CN201821030570.5U CN208571574U (en) 2018-06-29 2018-06-29 Low-voltage platform area neutral point drifting protective device

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109473947A (en) * 2018-06-29 2019-03-15 国家电网有限公司 A kind of low-voltage platform area neutral point drifting protective device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109473947A (en) * 2018-06-29 2019-03-15 国家电网有限公司 A kind of low-voltage platform area neutral point drifting protective device

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