CN207303988U - A kind of anti-secondary current circuit open circuit set of banked relay type - Google Patents

A kind of anti-secondary current circuit open circuit set of banked relay type Download PDF

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Publication number
CN207303988U
CN207303988U CN201721137760.2U CN201721137760U CN207303988U CN 207303988 U CN207303988 U CN 207303988U CN 201721137760 U CN201721137760 U CN 201721137760U CN 207303988 U CN207303988 U CN 207303988U
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CN
China
Prior art keywords
circuit
relay
secondary side
current
primary current
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.)
Expired - Fee Related
Application number
CN201721137760.2U
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Chinese (zh)
Inventor
蔡宇楼
熊兵
黄爱雄
李超
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
Yichang Power Supply Co of State Grid Hubei Electric Power Co Ltd
Original Assignee
State Grid Corp of China SGCC
Yichang Power Supply Co of State Grid Hubei Electric Power Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by State Grid Corp of China SGCC, Yichang Power Supply Co of State Grid Hubei Electric Power Co Ltd filed Critical State Grid Corp of China SGCC
Priority to CN201721137760.2U priority Critical patent/CN207303988U/en
Application granted granted Critical
Publication of CN207303988U publication Critical patent/CN207303988U/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

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Abstract

A kind of anti-secondary current circuit open circuit set of banked relay type, it includes current transformer, current transformer includes secondary side circuit, secondary side circuit includes primary current circuit, protective device is equipped with primary current circuit, secondary side circuit includes primary current circuit, external power driving circuit and short circuit circuit, primary current circuit and the same terminal connection for flowing into end and secondary side circuit in short circuit circuit, the electromagnetic mechanism of first relay is serially connected in primary current circuit, the electromagnetic mechanism of the normally-closed contact of first relay and the second relay is serially connected in external power driving circuit, the normally-closed contact of second relay is serially connected in short circuit circuit.The utility model can solve excitation magnetic potential caused by Current Transformer Secondary side is opened a way under abnormal condition in high-tension switch cabinet and increase severely, so that iron core overheats, the problems such as burning out mutual inductor, avoids personnel's secondary side in operation from opening a way, and produces high pressure and threatens personal equipment safety.

Description

A kind of anti-secondary current circuit open circuit set of banked relay type
Technical field
The utility model belongs to power supply facilities apparatus field, and in particular to a kind of anti-secondary current circuit of banked relay type Open circuit set.
Background technology
Current transformer is that one kind utilizes undesirable mutual electromagnetic inductance effect(When alternating current is connected with primary coil, iron core or magnetic core In just produce exchange flux, make to induce voltage or electric current in secondary coil)Primary side high current is converted into the small electricity of secondary side The monitoring instrument of stream.During work, first side winding is serially connected in a switching circuit, is a part for primary equipment;Secondary side Winding is then serially connected in metering or protective device, and during normal operation, which is circuit is connected all the time in closing by common ground end Conjunction state, since the impedance of secondary lateral load is low current coil, its working status is close to short-circuit condition.
According to the principle of magnetic potential balance, total magnetomotive force is primary side and the magnetomotive vector sum of secondary side.It is preferable In the case of, total magnetomotive force is zero, and there are magnetomotive force loss in real work, therefore total magnetomotive force very little.If secondary side circuit During generation open circuit situation, secondary side magnetomotive force is instantaneously zero, and primary side magnetomotive force is total magnetomotive force at this time, primary side current(Line Road load current)As excitation current, then excitation magnetic potential can uprush decades of times, cause current transformer iron core to overheat, or even burn Bad sensor.And because the number of turn of secondary side winding is more, high pressure can be induced and jeopardize the person and equipment safety.
In operation or maintenance process, Current Transformer Secondary side open circuit can produce many adverse consequences.First, overhauling When, since the secondary winding number of turn is more, the high voltage of sensing can threaten the person and equipment safety;Two be due to excitation magnetic potential increase, Cause loss increase iron core fever, damage insulation, burns out sensor;Third, the iron core burnt out can cause the generation of remanent magnetism, cause Phenomena such as accuracy of the current transformer in metering and measurement declines, and metering is inaccurate.
The content of the invention
The purpose of this utility model provides a kind of anti-secondary current circuit open circuit set of banked relay type, can solve high pressure Excitation magnetic potential caused by current transformer in switch cabinet secondary side is opened a way under abnormal condition increases severely so that iron core overheats, and burns The problems such as bad mutual inductor, avoid personnel's secondary side in operation from opening a way, produce high pressure and threaten personal safety.
In order to realize above-mentioned technical characteristic, the technical solution adopted in the utility model is:
A kind of anti-secondary current circuit open circuit set of banked relay type, it includes power supply, the second relay, the first relay Device(Sensor)And the external circuit of secondary side of current transformer, the external circuit of secondary side include primary current circuit, external power The electric current in driving circuit and short circuit circuit, primary current circuit and short circuit circuit flows into the same terminal of end and secondary side circuit Connection, primary current loop current outflow end are connected with external protective device, short circuit loop current outflow end ground connection.First relay For cross-core type sensor, primary current circuit is passed through from the first relay, the normally opened contact of the first relay and the second relay Electromagnetic mechanism be serially connected in external power driving circuit, the normally-closed contact of the second relay is serially connected in short circuit circuit.
The common end grounding of above-mentioned second relay normally closed contact, short circuit circuit are equipped with switch.
Above-mentioned switch is manual switch.
Using the above structure, the utility model has the following technical effect that:
1. sensor, power module, relay assembly are controlled for signal and operating switch returns to form new short circuit Road avoids the open fault that Current Transformer Secondary side produces;
2. during normal operation, when the improper open circuit of bad or operation is in contact in Current Transformer Secondary side, the device energy Enough rapid action message excision fault loops, prevent Current Transformer Secondary side from opening a way, ensure personnel and equipment safety;
It is grounded 3. being introduced short circuit current using public N points, while CT failures broken string is not detected in interference protection device Signal;
4. during normal operation, the improper secondary side that occurs of bad or operation is in contact in Current Transformer Secondary side and is opened a way When, which can cut off fault loop by action message rapidly, prevent Current Transformer Secondary side from opening a way, ensure personnel and equipment Safety.
Brief description of the drawings
The utility model is described in further detail with reference to the accompanying drawings and examples.
Fig. 1 is the circuit diagram of Current Transformer Secondary side loop in the utility model;
Fig. 2 is the structure diagram of the utility model.
Embodiment
The embodiment of the utility model is described further below in conjunction with the accompanying drawings.
As shown in Figure 1, a kind of anti-secondary current circuit open circuit set of banked relay type, it includes power supply 8, the second relay The external circuit of secondary side of device 6, the first relay 4 and current transformer, the external circuit of secondary side include primary current circuit 1, The electric current in external power driving circuit 2 and short circuit circuit 3, primary current circuit 1 and short circuit circuit 3 flows into end and secondary side circuit The connection of same terminal, 1 electric current outflow end of primary current circuit be connected with external protective device, and 3 electric current of short circuit circuit, which flows out, to be terminated Ground.First relay 4 is cross-core type sensor, and primary current circuit 1 is passed through from the first relay 4, and the normally opened of the first relay 4 touches The electromagnetic mechanism of 5 and second relay 6 of point is serially connected in external power driving circuit 2, and the normally-closed contact 7 of the second relay concatenates In short circuit circuit 3.
The common end grounding of second relay normally closed contact 7, short circuit circuit 3 are equipped with switch 9.
The switch 9 is manual switch.
Specifically, as shown in Figure 1, realized using the method being improved to former secondary side current circuit.Primary current is returned A signal relay is sealed in road;When former circuit normal operation, contact disconnects;When former circuit is opened a way, contact is closed Splice grafting leads to relay(The circuit can connect external power and is also formed into a loop from charged pool);Then contact closure closes short circuit circuit Close, another turns on the circuit of mutual inductor connection, avoids the safety problem that Current Transformer Secondary side open circuit is brought.
By taking mutual inductor secondary side A phase currents as an example, primary current loop current flows into terminal AL from AS and flows out terminal to protection Device, when open fault occurs in it, performance loop action makes short circuit circuit conducting secondary side current flow to the earth by N-terminal, keeps away Secondary side current circuit open circuit is exempted from, short circuit circuit flows into end AD end starting points and AS ends starting point, and to be all connected on mutual inductor secondary side same On terminal, protection screen backstage can still send CT disconnection signals at this time, then searched and recovered by service personnel.
Using the above structure, in use, being then laid out the actual conditions of banked relay module combination cabinet inner terminal case Installed as shown in Fig. 2, providing power supply, the normally closed contact of relay in AC power connecting terminal case(CB)Connect current transformer By the secondary side terminal in protective current circuit, common port(COM)Arranged by a single-phase access earth bus that is spaced apart.It is protected The secondary current circuit(Primary current circuit)Pass through sensor so that the current loop can be monitored.
After installation and debugging, interval is spaced apart manually before putting into operation to be off, after normal operation is put into operation at interval, Closure being spaced apart manually, CB is in operating state, that is, off-state at this time, when former secondary current circuit is opened a way, electric current in circuit For 0, normal condition, that is, closure state at CB at this time, CB terminals closure, which will form a new short circuit circuit, prevents current transformer Secondary side open fault.

Claims (4)

1. a kind of anti-secondary current circuit open circuit set of banked relay type, it includes power supply(8), the second relay(6), first Relay(4)And the external circuit of secondary side of current transformer, it is characterised in that:The external circuit of secondary side includes former electricity Flow back to road(1), external power driving circuit(2)And short circuit circuit(3), primary current circuit(1)And short circuit circuit(3)Electric current The same terminal for flowing into end and secondary side circuit connects, primary current circuit(1)Electric current outflow end is connected with external protective device, short Take back road(3)Electric current outflow end is grounded.
A kind of 2. anti-secondary current circuit open circuit set of banked relay type according to claim 1, it is characterised in that:Institute State the first relay(4)For cross-core type sensor, primary current circuit(1)From the first relay(4)In pass through, the first relay(4) Normally opened contact(5)And second relay(6)Electromagnetic mechanism be serially connected in external power driving circuit(2)In, the second relay Normally-closed contact(7)It is serially connected in short circuit circuit(3)In.
A kind of 3. anti-secondary current circuit open circuit set of banked relay type according to claim 1, it is characterised in that:Institute State the second relay normally closed contact(7)Common end grounding, short circuit circuit(3)It is equipped with switch(9).
A kind of 4. anti-secondary current circuit open circuit set of banked relay type according to claim 3, it is characterised in that:Institute State switch(9)For manual switch.
CN201721137760.2U 2017-09-06 2017-09-06 A kind of anti-secondary current circuit open circuit set of banked relay type Expired - Fee Related CN207303988U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201721137760.2U CN207303988U (en) 2017-09-06 2017-09-06 A kind of anti-secondary current circuit open circuit set of banked relay type

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201721137760.2U CN207303988U (en) 2017-09-06 2017-09-06 A kind of anti-secondary current circuit open circuit set of banked relay type

Publications (1)

Publication Number Publication Date
CN207303988U true CN207303988U (en) 2018-05-01

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Family Applications (1)

Application Number Title Priority Date Filing Date
CN201721137760.2U Expired - Fee Related CN207303988U (en) 2017-09-06 2017-09-06 A kind of anti-secondary current circuit open circuit set of banked relay type

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CN (1) CN207303988U (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110912079A (en) * 2019-11-04 2020-03-24 深圳供电局有限公司 Method for switching secondary current loop of CT (current transformer) during operation of bypass transformer switch

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110912079A (en) * 2019-11-04 2020-03-24 深圳供电局有限公司 Method for switching secondary current loop of CT (current transformer) during operation of bypass transformer switch

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GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20180501

Termination date: 20190906