CN106353551B - Combined open-circuit-proof current terminal with indication - Google Patents
Combined open-circuit-proof current terminal with indication Download PDFInfo
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- CN106353551B CN106353551B CN201610783728.5A CN201610783728A CN106353551B CN 106353551 B CN106353551 B CN 106353551B CN 201610783728 A CN201610783728 A CN 201610783728A CN 106353551 B CN106353551 B CN 106353551B
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- wire
- energy storage
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- storage spring
- current
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
- G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
- G01R15/18—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using inductive devices, e.g. transformers
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F27/00—Details of transformers or inductances, in general
- H01F27/28—Coils; Windings; Conductive connections
- H01F27/29—Terminals; Tapping arrangements for signal inductances
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F38/00—Adaptations of transformers or inductances for specific applications or functions
- H01F38/20—Instruments transformers
- H01F38/22—Instruments transformers for single phase ac
- H01F38/28—Current transformers
- H01F38/30—Constructions
Abstract
The utility model provides a combination formula of area instruction prevents current terminal that opens a way, it includes defeated flow part, connecting piece and overcurrent part, defeated flow part includes first defeated flow electric wire and with first defeated flow electric wire parallel arrangement's second defeated flow electric wire, the one end of first defeated flow electric wire and second defeated flow electric wire is equipped with first sinle silk and second sinle silk, be equipped with first crimping board and second crimping board in two sinle silks that are parallel to each other, the one end of two crimping boards is connected with the inboard of two sinle silks respectively, the other end of two crimping boards is connected with the one end of first spring and the second spring of renaming respectively, the other end of two springs of renaming is connected with indicating mechanism respectively, be equipped with first energy storage spring and second energy storage spring between the middle section of first crimping board and first sinle silk and between second crimping board and the second sinle silk respectively. The invention can solve the problems that the excitation magnetic potential is increased sharply to cause the overheating of the iron core and even to burn out the sensor caused by the open circuit of the secondary side of the current transformer under the abnormal condition.
Description
Technical Field
The invention relates to a design of a combined open-circuit-proof current terminal with an indication function, and relates to the field of secondary signal measurement of a current transformer of an electric power system.
Background
The current transformer principle is made according to the transformer principle. The current transformer is composed of a closed iron core and a winding. The primary side winding of the current transformer has few turns and is connected in series in a circuit of current to be measured, so that all current of the circuit always flows through the current transformer, the secondary side winding has more turns and is connected in series in a measuring instrument and a protection circuit, and when the current transformer works, the secondary side circuit of the current transformer is always closed, so that the impedance of the series coil of the measuring instrument and the protection circuit is very small, and the working state of the current transformer is close to short circuit. The current transformer converts a large current on the primary side into a small current on the secondary side for measurement.
Because the load of the secondary side of the current transformer is a small-impedance current coil, the secondary side of the current transformer works in a state close to a short circuit. According to a magnetomotive force balance formula: I.C. A 1 N 1 -I 2 N 2 ＝I 0 N 1 It is known that I is due to 1 N 1 Most part of quilt I 2 N 2 Cancel out, so the total magnetomotive force I 0 N 1 Very small, i.e. excitation current I 0 Very small, having only a primary current I 1 A few percent. If the secondary side is open-circuited, then I 2 =0, having I 1 N 1 ＝I 0 N 1 I.e. I 1 ＝I 0 ，I 1 Is a primary circuit load current, is not changed by a secondary load of the mutual inductor, and the exciting current is I 1 The exciting magnetic potential is sharply increased by dozens of times, which can cause the iron core to be overheated and even burn out the sensor, and the induced high voltage crisis the safety of human and equipment due to a plurality of turns of the secondary winding. An open circuit on the secondary side of a current transformer during operation may have the following phenomena and consequences:
1. because the magnetic flux in the iron core is saturated, several kilovolts of high voltage are generated on the secondary side, and the open circuit point can possibly generate discharge phenomena, discharge sparks and discharge sound;
2. because the magnetic flux in the iron core is saturated, the loss is increased to generate heat, the insulation is damaged, and abnormal sound and peculiar smell exist;
3. the ammeter connected with the current transformer indicates that the swing is indefinite or no indication exists, and the rotating speed of the watt-hour meter is abnormal;
4. high voltage is generated to threaten the safety of human bodies and equipment;
5. the iron core generates heat, even burns out insulation;
6. metering is inaccurate, and even if a secondary circuit is repaired, the metering accuracy is reduced due to residual magnetism;
7. the ammeter indicates an anomaly.
Disclosure of Invention
The technical problem to be solved by the invention is to solve the defects of the prior art, and the provided combined open-circuit-proof current terminal with the indication can solve the problems that the excitation magnetic potential is increased greatly, an iron core is overheated and even a sensor is burnt down due to the fact that the secondary side of the current transformer is opened under an abnormal condition.
The purpose of the invention is realized by the following steps:
a combined open-circuit-proof current terminal with indication comprises a current transmission part, a connecting piece and a current receiving part, wherein the current transmission part comprises a first current transmission wire and a second current transmission wire arranged in parallel with the first current transmission wire, one end of the first current transmission wire and one end of the second current transmission wire are provided with a first wire core and a second wire core, a first crimping plate and a second crimping plate are arranged in the two wire cores which are parallel to each other, one end of each of the two crimping plates is connected with the inner sides of the two wire cores respectively, the other ends of the two crimping plates are connected with one ends of a first centering spring and a second centering spring respectively, the other ends of the two centering springs are connected with an indication mechanism respectively, and a first energy storage spring and a second energy storage spring are arranged between the middle section of the first crimping plate and the first wire core and between the second crimping plate and the second wire core respectively;
the current receiving component comprises a first current receiving wire, a second current receiving wire, a first short connecting plate and a second short connecting plate, one end of the first current receiving wire and one end of the second current receiving wire are respectively provided with a third wire core and a fourth wire core, the first current receiving wire and the second current receiving wire are parallel to each other, the first short connecting plate and the second short connecting plate respectively comprise a first side plate, a second side plate connected with the first side plate in a 90-degree mode, a third side plate connected with the second side plate in a 90-degree mode, the length of the first side plate is smaller than that of the third side plate, the first side plate of the first short connecting plate is connected with the fourth wire core, the first side plate of the second short connecting plate is connected with the third wire core, a U-shaped limiting plate is arranged between the fourth wire core and the third wire core, a third energy storage spring and a fourth energy storage spring are respectively arranged between the U-shaped limiting plate and the fourth wire core, the first short connecting plate is arranged on the third energy storage spring, the fourth energy storage spring is provided with the second short connecting plate, and the third energy storage spring are respectively fixedly connected with the U-shaped limiting plate at the end portions.
The first wire core and the second wire core are disposed in the first terminal wiring groove.
The third wire core and the fourth wire core are arranged in the second terminal wiring groove.
And the third energy storage spring and the fourth energy storage spring are respectively provided with a first warning indication mechanism and a second warning indication mechanism, the first warning indication mechanism pops up through the upper end window, and the second warning indication mechanism pops up through the lower end window.
The indicating mechanism is connected with the sliding groove of the left observation window b; the first shorting plate and the second shorting plate are welded inside the terminal.
The left side of the indicating mechanism is provided with a terminal shell with an observation window, and the indicating mechanism is a conductive metal strip coated with red, green and red three-layer indications on the surface. When the loop is not normally opened, the indicating mechanism is centered, and the observation window displays a green normal indicating strip; when the circuit is opened, the press-connection plate drives the indicating mechanism to move up or down, and the observation window displays red fault indication strip connection.
By adopting the structure, the following technical effects can be brought:
1) The combined type open-circuit-proof current terminal is provided with an indication. The current terminal comprises 3 main components: a flow transmission part, a flow receiving part and a connecting piece. The three parts can be combined into a current transformer secondary side current terminal used by an electrical secondary system, different assemblies are flexibly matched according to the front part and the rear part in an electrical loop, when loop wiring or screw terminals are loosened and fall off or wiring is not performed due to human errors, fault points can be rapidly cut off through internal mechanism actions, and personnel and equipment injuries caused by open circuit of the secondary side of the current transformer or measurement misalignment and protection misoperation caused by poor contact are avoided. Meanwhile, the current terminal has a secondary side open circuit point indicating function, and fault points are conveniently searched and processed;
2) The current terminal in the secondary measurement loop of the current transformer can be replaced by the combination of the current transmission component, the current receiving component and the middle connecting piece of the current transmission component and the current receiving component, and the current transmission component and the current receiving component can quickly and reliably act to cut off a fault loop when the loop wiring is in poor contact or falls off and a terminal screw is loosened, so that the secondary loop of the current transformer is prevented from being opened, and the safety of personnel and equipment is ensured;
3) The current transmission component and the current receiving component are standardized modules, can be used as a terminal transfer function through the connecting component, and can also be used for a measuring device which needs to be accessed with a secondary signal of the current transformer, after the current measuring device uses the components, the protection function of preventing the secondary side of the current transformer from being open can be realized, and the measurement precision of the device body is not influenced under the normal condition;
4) No matter it is defeated flow part or receive flow part, when the open circuit trouble of two side return circuits of current transformer takes place by this design after the terminal isolation, current terminal body has open circuit protection action indicator, and the actual action side of open circuit current terminal can be represented to the indicator, the analysis and the processing of trouble of being convenient for. Meanwhile, if the peripheral conditions are met, the signal indicator action signal can be sent up;
5) This design uses mechanical parts completely, does not have the return circuit interference that the cluster electricity or electromagnetism caused, still can guarantee equipment normal and personnel's safety under the terminal self condition of taking place unusually. In view of the severity of the open circuit of the secondary side loop of the current transformer and the response requirement after the fault occurs, the combined open-circuit-preventing current terminal with the indication has obvious use advantages and popularization value.
Drawings
The invention is further illustrated by the following examples in conjunction with the accompanying drawings:
FIG. 1 is a schematic structural view of the overall normal operation of the present invention;
FIG. 2 is a schematic structural diagram of the present invention when an open-circuit fault occurs as a whole;
FIG. 3 is a schematic view of the internal structure of the fluid transport component of the present invention in normal operation;
FIG. 4 is a schematic diagram of an internal structure of an open circuit fault of a fluid transfer component according to the present invention;
FIG. 5 is a schematic view of the internal structure of the current-receiving component of the present invention in normal operation;
fig. 6 is a schematic diagram of an internal mechanism of the open circuit fault of the current-receiving component in the invention.
Detailed Description
In fig. 1, the function of the relay connector is consistent with that of a common current terminal, and the relay connector plays a role in signal relay. In FIG. 2, phase A is illustrated as an example.
1) The fault of the current transmission side is used for short-circuiting the incoming line wiring of the open circuit phase; when an open circuit 1 fault occurs from the phase A of the secondary circuit of the current transformer to the connecting terminal of the AS end of the sensor, the current transmission part mechanism acts to realize short circuit 1, then the open circuit 1 is isolated, the phase A of the secondary side of the current transformer still forms a closed circuit, the phase current of the sensor and the phase A of the rear end connecting device of the sensor is lost, and the front end and the transformer body normally operate.
2) A current receiving side fault short-circuits a current receiving side terminal; when the A phase of the secondary circuit of the current transformer generates an open circuit 2 fault to the AL end connecting terminal of the sensor, the current receiving part mechanism acts to realize a short circuit 2, the open circuit 2 is isolated, the A phase of the secondary side of the current transformer still forms a closed circuit, only the A phase current of the sensor body is lost, and the front end, the rear end and the transformer body normally operate.
3) If an open circuit fault occurs in a sensor body terminal, taking an AS \ AL terminal fault AS an example, after the fault is realized by the current transmission component, the AS and the AL are in short circuit, the open circuit point is isolated, the phase A on the secondary side of the current transformer still forms a closed loop, only the phase current of the sensor body A is lost, and the front end, the rear end and the transformer body normally operate.
As shown in fig. 3 and 4, the internal mechanism acts when the fluid transmission component works normally and the open circuit is in fault;
1. the virtual lines are terminal wiring grooves, the mechanisms a, b and c in normal operation state are not connected electrically, the energy storage spring and the compression joint plate are integrated, and the middle spring, the energy storage spring body and the contact surface are insulated.
2. The wiring between crimping board and defeated electric wire 1, 2 sinle silks is special cold pressing head (sinle silks side is ordinary cold pressing head, and crimping board side is special joint and sinle silks cold pressing head realization physical connection and electrical conduction), and the cable core well switches on with crimping board a or c after the crimping.
3. During normal operation, return spring makes b be in the intermediate position, the crimping board is in between limiting plate and the sinle silk, and energy storage spring is compressed.
4. When an open circuit fault occurs (taking the fact that the current transmission wire 1 is loosened or falls off as an example, the wire 2 is the same as the wire 1 when the open circuit occurs), the wire core of the current transmission wire 1 slides out of the terminal wiring groove, the connected crimping plate is driven to be separated from the limit plate for limitation, displacement and b switch-on and pressing-down occur under the action force of the energy storage spring, b moves under the action force of the energy storage spring of the crimping plate to be connected with the c crimping plate, at the moment, the wire cores of the current transmission wire 1 and the current transmission wire 2 are in short circuit connection by a, b and c, a fault point is cut off, and the front-end device and the current transformer can normally operate.
5.b when the lower end of the switch moves to the open-circuit action position, the lower end action indication block is exposed out of the observation window, and the open-circuit protection can be judged to be actuated. And the alarm signals can be sent to a monitoring system through the wiring terminals on the a and the c.
6. After open-circuit fault treatment (recovery or wire pressing), under the action of the centering spring, the b automatically returns to the neutral position, the electric connection of the current transmission wires 1 and 2 is disconnected, and the loop recovers normal operation.
Fig. 5 and 6 show the action of the internal mechanism when the current-receiving component works normally and the open circuit fails;
1. and in a normal running state, the core of the current receiving wire 1 or 2 is not electrically connected with the short splicing piece or the short circuit plate, and the energy storage spring body and the contact surface are subjected to insulation treatment.
2. When an open circuit fault occurs (taking the fact that the current transmission wire 1 is loosened or falls off as an example, the wire 2 is the same as the wire 1 when being opened), the energy storage spring is released to move upwards, the short connection plate arranged on the spring is communicated with the short connection row to the wire core 2, namely, the terminal wiring terminals of the wire cores 1 and 2 are in short circuit, the short circuit is connected with the measuring element, the loop current is cut off, the measuring loops at the front end and the rear end are not influenced, and the current transformer normally operates.
3. When the energy storage spring moves up to the open-circuit action position when the open-circuit fault occurs, the action indication block at the upper end of the energy storage spring is exposed out of the observation window, and the action of the open-circuit protection can be judged. The alarm signal can be sent up to the monitoring system via the terminal block located in the shorting tab and the terminal wiring slot.
4. After open-circuit fault treatment (recovery or wire pressing), the energy storage spring retracts to the initial position under the action of the pressure of the wire core, the electric connection of the current transmission wires 1 and 2 is disconnected, and the loop recovers to normal operation.
The connecting member physically and electrically connects only the flow transmitting member and the flow receiving member. The connecting piece can be provided with a test slider and a wiring terminal. Preferably, the connecting part is a phoenix terminal, wherein the sliding block can electrically connect or disconnect the current transmission end and the current receiving end, and the test terminals at the two ends can be connected to the test wire through a special wiring terminal.
Claims (6)
1. The utility model provides an area is instructed combination formula and is prevented open circuit current terminal, it includes defeated flow part, connecting piece and receives flow part, its characterized in that: the flow transmission component comprises a first flow transmission wire (1) and a second flow transmission wire (2) arranged in parallel with the first flow transmission wire (1), one ends of the first flow transmission wire (1) and the second flow transmission wire (2) are provided with a first wire core (3) and a second wire core (8), a first crimping plate (5) and a second crimping plate (9) are arranged in the two wire cores which are parallel to each other, one ends of the two crimping plates are respectively connected with the inner sides of the two wire cores, the other ends of the two crimping plates are respectively connected with one ends of a first centering spring (6) and a second centering spring (10), the other ends of the two centering springs are respectively connected with an indicating mechanism (7), and a first energy storage spring (11) and a second energy storage spring (12) are respectively arranged between the middle section of the first crimping plate (5) and the first wire core (3) and between the middle section of the second crimping plate (9) and the second wire core (8);
the current receiving component comprises a first current receiving wire (13), a second current receiving wire (14), a first short connecting plate (17) and a second short connecting plate (18), one end of the first current receiving wire (13) and one end of the second current receiving wire (14) are respectively provided with a third wire core (15) and a fourth wire core (16), the first current receiving wire (13) and the second current receiving wire (14) are parallel to each other, the first short connecting plate (17) and the second short connecting plate (18) respectively comprise a first side plate, a second side plate connected with the first side plate at an angle of 90 degrees and a third side plate connected with the second side plate at an angle of 90 degrees, the length of the first side plate is smaller than that of the third side plate, the first side plate of the first short connecting plate (17) is connected with the fourth wire core (16), and the first side plate of the second short connecting plate (18) is connected with the third wire core (15), a U-shaped limiting plate (23) is arranged between the fourth wire core (16) and the third wire core (15), a third energy storage spring (19) and a fourth energy storage spring (20) are respectively arranged between the U-shaped limiting plate (23) and the third wire core (15) and between the U-shaped limiting plate (23) and the fourth wire core (16), a first short connecting piece (21) is arranged on the third energy storage spring (19), a second short connecting piece (22) is arranged on the fourth energy storage spring (20), and the end parts of the third energy storage spring (19) and the fourth energy storage spring (20) are respectively fixedly connected with the U-shaped limiting plate (23); when open circuit trouble takes place, energy storage spring release shifts up, installs shorting strip and sinle silk switch-on energy storage spring for the binding post of sinle silk is short circuited.
2. The modular open circuit prevention current terminal of claim 1, wherein: the first and second cores (3, 8) are disposed in the first terminal wiring groove (4).
3. The combined open-circuit prevention current terminal with indication of claim 1, wherein: the third wire core (15) and the fourth wire core (16) are arranged in a second terminal connection slot (24).
4. The modular open circuit prevention current terminal of claim 1, wherein: and a first warning indication mechanism (25) and a second warning indication mechanism (26) are respectively arranged on the third energy storage spring (19) and the fourth energy storage spring (20), the first warning indication mechanism (25) pops up through an upper end window, and the second warning indication mechanism (26) pops up through a lower end window.
5. The modular open circuit prevention current terminal of claim 1, wherein: the indicating mechanism (7) is connected with the chute of the left observation window b; the first shorting plate (17) and the second shorting plate (18) are welded inside the terminal.
6. The combined open-circuit prevention current terminal with indication according to claim 1 or 5, wherein: the left side of the indicating mechanism (7) is provided with a terminal shell with an observation window, and the indicating mechanism (7) is a conductive metal strip coated with red, green and red indications on the surface; when the loop is not normally opened, the indicating mechanism is centered, and the observation window displays a green normal indicating strip; when the circuit is opened, the press-connection plate drives the indicating mechanism to move up or down, and the observation window displays red fault indication strip connection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610783728.5A CN106353551B (en) | 2016-08-31 | 2016-08-31 | Combined open-circuit-proof current terminal with indication |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610783728.5A CN106353551B (en) | 2016-08-31 | 2016-08-31 | Combined open-circuit-proof current terminal with indication |
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| Publication Number | Publication Date |
|---|---|
| CN106353551A CN106353551A (en) | 2017-01-25 |
| CN106353551B true CN106353551B (en) | 2023-03-21 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610783728.5A Active CN106353551B (en) | 2016-08-31 | 2016-08-31 | Combined open-circuit-proof current terminal with indication |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008306783A (en) * | 2007-06-05 | 2008-12-18 | Toshiba Mitsubishi-Electric Industrial System Corp | Protective device for current transformer |
| CN201402859Y (en) * | 2009-04-17 | 2010-02-10 | 珠海许继电气有限公司 | CT open circuit preventing connector of outdoor trolly wire |
| CN202093972U (en) * | 2011-05-31 | 2011-12-28 | 郑州人造金刚石及制品工程技术研究中心有限公司 | Current transformer with open circuit protection indication |
| CN202695118U (en) * | 2012-07-17 | 2013-01-23 | 大厂回族自治县开元电力技术有限公司 | Novel open-type current transformer |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN206020505U (en) * | 2016-08-31 | 2017-03-15 | 中国长江电力股份有限公司 | A kind of band indicates the anti-open-circuit current terminal of combination type |
-
2016
- 2016-08-31 CN CN201610783728.5A patent/CN106353551B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008306783A (en) * | 2007-06-05 | 2008-12-18 | Toshiba Mitsubishi-Electric Industrial System Corp | Protective device for current transformer |
| CN201402859Y (en) * | 2009-04-17 | 2010-02-10 | 珠海许继电气有限公司 | CT open circuit preventing connector of outdoor trolly wire |
| CN202093972U (en) * | 2011-05-31 | 2011-12-28 | 郑州人造金刚石及制品工程技术研究中心有限公司 | Current transformer with open circuit protection indication |
| CN202695118U (en) * | 2012-07-17 | 2013-01-23 | 大厂回族自治县开元电力技术有限公司 | Novel open-type current transformer |
Non-Patent Citations (1)
| Title |
|---|
| 徐惜琼等.电流互感器二次开路保护装置的应用分析和改进.2014,全文. * |
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