CN205670677U - A kind of earth leakage protective device - Google Patents
A kind of earth leakage protective device Download PDFInfo
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- CN205670677U CN205670677U CN201620386472.XU CN201620386472U CN205670677U CN 205670677 U CN205670677 U CN 205670677U CN 201620386472 U CN201620386472 U CN 201620386472U CN 205670677 U CN205670677 U CN 205670677U
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Abstract
The utility model discloses a kind of earth leakage protective device, including: zero sequence current mutual inductor, its primary side connects ac circuit, for the zero-sequence current obtained when described ac circuit occurs electric leakage in circuit；Leakage current processing unit, connects the secondary side of described zero sequence current mutual inductor, for the current signal that described zero sequence current mutual inductor exports is converted into voltage signal；Microprocessor, its input port connects the outfan of described leakage current processing unit, for judging whether the voltage signal that described leakage current processing unit exports is more than voltage threshold, if more than, send earth leakage protective and perform instruction；Action execution unit, its input connects the outfan of described microprocessor, is used for receiving after described earth leakage protective performs instruction and cuts off described current supply circuit；Digital input interface, connects the user setup end of described microprocessor, is used for arranging described voltage threshold.Residual current operating value can be set flexibly, it is to avoid protection's dead-zone.
Description
Technical field
This utility model relates to earth leakage protective field, is specifically related to a kind of earth leakage protective device.
Background technology
The raising recognized earth leakage protective along with people, the range of application of earth leakage protective device constantly expands, and the most generally adopts
Using aftercurrent action protecting method, when equipment residual current reaches certain residual current value, earth leakage protective device is with regard to action, right
Equipment is protected.Under normal conditions, intrinsic in circuit residual current is usually slowly varying.If it is intrinsic in circuit
Residual current fluctuate up and down at higher value, for guaranteeing that equipment normally works, the residual current operating value that earth leakage protective device is specified
It is accomplished by arranging bigger.
But, the specified residual current operating value of earth leakage protective device is usually fixing nonadjustable, needs to estimate in circuit
Intrinsic residual current value, chooses the electric leakage bigger and proximate to it than intrinsic residual current value of specified residual current operating value and protects
Protect device.If the residual current operating value of the selected earth leakage protective device residual current value more intrinsic than in circuit is much larger, then deposit
At protection's dead-zone.
Summary of the invention
The technical problems to be solved in the utility model is the residual current overcoming earth leakage protective device in prior art specified
Working value fixes non-adjustable, to there is protection's dead-zone defect.
To this end, this utility model embodiment provides a kind of earth leakage protective device, including: zero sequence current mutual inductor, it is once
Side connects ac circuit, for the zero-sequence current obtained when described ac circuit occurs electric leakage in circuit；Leakage current processes single
Unit, connects the secondary side of described zero sequence current mutual inductor, for the current signal conversion exported by described zero sequence current mutual inductor
Become voltage signal；Microprocessor, its input port connects the outfan of described leakage current processing unit, is used for judging described leakage
Whether the voltage signal of electricity current processing unit output is more than voltage threshold, if being more than, sending earth leakage protective and performing instruction；Dynamic
Making performance element, its input connects the outfan of described microprocessor, after being used for receiving the execution instruction of described earth leakage protective
Cut off described current supply circuit；Digital input interface, connects the user setup end of described microprocessor, is used for arranging described voltage threshold
Value.
Preferably, described leakage current processing unit includes: signal conversion subelement, its input and described zero-sequence current
The secondary side of transformer connects, for zero sequence current signal is converted to voltage signal；Seamless subelement, its input is with described
The outfan of signal conversion unit connects, for the negative voltage transition of sine voltage signal is become positive voltage；Amplify subelement, its
Input is connected with the outfan of described seamless subelement, for being put by the voltage signal that described seamless subelement exports
Greatly, its outfan is connected with described microprocessor.
Preferably, described signal conversion subelement includes: be connected on the resistance of the secondary side of described zero sequence current mutual inductor
R1；Described resistance R1 and diode D1, diode D2 three are in parallel；The positive pole of described diode D1 connects the negative of described diode D2
Pole, the negative pole of described diode D1 connects the positive pole of described diode D2；Described resistance R1 two ends are also parallel with resistance R2 and electric capacity
C1, described resistance R2 and described electric capacity C1 connect.
Preferably, described seamless subelement includes: inverting amplifier OP1, and its negative input connects one end of resistance R3,
The other end of described resistance R3 connects between described resistance R2 and described electric capacity C1；Its positive input ground connection；It exports termination
The positive pole of diode D3, the negative pole of described diode D3 connects one end of resistance R4, the other end of described resistance R4 with described instead
The negative input of phase amplifier OP1 connects；Described resistance R3 is identical with described resistance R4 resistance.
Preferably, described amplification subelement includes: operational amplifier OP2, and its positive input connects described diode D3
Negative pole, its negative input pass through resistance R5 ground connection, its outfan connect resistance R6 one end, the other end of described resistance R6
Connect the negative input of described operational amplifier OP2；Electric capacity C2 is in parallel with described resistance R6.
Preferably, described leakage current processing unit also includes: resistance R7, and its one end connects described operational amplifier OP2
Outfan, the other end connect described microprocessor；It is also associated with electric capacity C3 between described resistance R7 and described microprocessor,
The other end ground connection of described electric capacity C3.
Preferably, described device also includes: threephase current transformer and three-phase current signal processing unit, described three-phase electricity
Current transformer primary side connects described ac circuit, and secondary side connects described three-phase current signal processing unit, described three-phase electricity
The outfan of stream signal processing unit connects described embedded microprocessor；And/or, threephase potential transformer and three-phase voltage letter
Number processing unit, described threephase potential transformer primary side connects described ac circuit, and secondary side connects described three-phase voltage letter
Number processing unit, the outfan of described three-phase voltage signal processing unit connects described embedded microprocessor.
Preferably, described device also includes display screen, for showing the residual current of described ac circuit.
Preferably, described device also includes network communication unit, connects described embedded microprocessor, for by described friendship
The residual current flowing back to road is transferred to host computer or remote monitoring terminal.
This utility model embodiment technical scheme, has the advantage that
1. the earth leakage protective device that this utility model embodiment provides, obtains ac circuit by zero sequence current mutual inductor and sends out
During raw electric leakage, the zero-sequence current in circuit, is converted into the current signal of zero sequence current mutual inductor by leakage current processing unit
Whether voltage signal, by the voltage signal of microprocessor judges leakage current processing unit output more than voltage threshold, if greatly
Perform instruction in then sending earth leakage protective, receive earth leakage protective execution instruction rear cutout cut-off electricity by action execution unit and return
Road, arranges voltage threshold by connecting the digital input interface of microprocessor, it is possible to arrange residual current operating value flexibly, it is to avoid
Protection's dead-zone.
2. the earth leakage protective device that this utility model embodiment provides, signal conversion of its leakage current processing unit is single
Unit includes that the resistance R1 being connected on the secondary side of zero sequence current mutual inductor, this resistance R1 are with diode D1, diode D2 three also
Connection, the positive pole of diode D1 connects the negative pole of diode D2, and the negative pole of diode D1 connects the positive pole of diode D2, when resistance R1 two ends
When voltage is higher than the conducting voltage of diode D1 and D2, D1 or D2 is switched on, and electric current is no longer flow through resistance R2 and subsequent conditioning circuit thereof.
Voltage clamp is carried out, to guarantee that the voltage of input microprocessor will not be too high and right after amplified process by diode D1 and D2
Microprocessor causes damage.
3. the earth leakage protective device that this utility model embodiment provides, also includes network communication unit, connects embedding and declines
Processor, for being transferred to host computer or remote monitoring terminal by the residual current of ac circuit, it is achieved remotely adjusts this electric leakage
The voltage threshold of protection device, information inquiry, and download fault parameter.
Accompanying drawing explanation
In order to be illustrated more clearly that this utility model detailed description of the invention or technical scheme of the prior art, below by right
In detailed description of the invention or description of the prior art, the required accompanying drawing used is briefly described, it should be apparent that, describe below
In accompanying drawing be embodiments more of the present utility model, for those of ordinary skill in the art, do not paying creativeness
On the premise of work, it is also possible to obtain other accompanying drawing according to these accompanying drawings.
Fig. 1 is the theory diagram of earth leakage protective device in this utility model embodiment 1；
Fig. 2 is the circuit theory diagrams of the leakage current processing unit of earth leakage protective device in this utility model embodiment 1.
Detailed description of the invention
Below in conjunction with accompanying drawing, the technical solution of the utility model is clearly and completely described, it is clear that described
Embodiment is a part of embodiment of this utility model rather than whole embodiments.Based on the embodiment in this utility model, this
The every other embodiment that field those of ordinary skill is obtained under not making creative work premise, broadly falls into this practicality
Novel protected scope.
In description of the present utility model, " " center ", " on ", D score, "left", "right", " perpendicular it should be noted that term
Directly ", " level ", " interior ", the orientation of the instruction such as " outward " or position relationship be based on orientation shown in the drawings or position relationship, be only
Must have specific for the ease of describing this utility model and simplification description rather than instruction or the device of hint indication or element
Orientation, with specific azimuth configuration and operation, therefore it is not intended that to restriction of the present utility model.Additionally, term " the
One ", " second ", " the 3rd " are only used for describing purpose, and it is not intended that instruction or hint relative importance.
In description of the present utility model, it should be noted that unless otherwise clearly defined and limited, term " peace
Dress ", should be interpreted broadly " being connected ", " connection ", for example, it may be fix connection, it is also possible to be to removably connect, or integratedly
Connect；Can be to be mechanically connected, it is also possible to be electrical connection；Can be to be joined directly together, it is also possible to be indirectly connected to by intermediary,
Can also is that the connection of two element internals, can be wireless connections, it is also possible to be wired connection.Common skill for this area
For art personnel, above-mentioned term concrete meaning in this utility model can be understood with concrete condition.
As long as additionally, technical characteristic involved in this utility model difference embodiment disclosed below is each other
The conflict of not constituting just can be combined with each other.
Embodiment 1
The present embodiment provides a kind of earth leakage protective device, it is adaptable to distribution transformer low-pressure side three-phase and four-line neutral point is direct
The low voltage electric network system of ground connection, as it is shown in figure 1, include zero sequence current mutual inductor 1, leakage current processing unit 2, microprocessor 3,
Action execution unit 4 and digital input interface 5.
Zero sequence current mutual inductor 1, its primary side connects ac circuit, when being used for obtaining ac circuit generation electric leakage in circuit
Zero-sequence current.
Leakage current processing unit 2, connects the secondary side of zero sequence current mutual inductor, for being exported by zero sequence current mutual inductor
Current signal be converted into voltage signal.
Microprocessor 3, its input port connects the outfan of leakage current processing unit, is used for judging that leakage current processes
Whether the voltage signal of unit output is more than voltage threshold, if being more than, sending earth leakage protective and performing instruction.Connect microprocessor
Outfan, be used for receiving earth leakage protective and perform instruction rear cutout and break current supply circuit.
Action execution unit 4, its input connects the outfan of microprocessor, is used for receiving earth leakage protective and performs instruction
Rear cutout is broken current supply circuit.This action execution unit can be relay or chopper.
Digital input interface 5, connects the user setup end of microprocessor, is used for arranging voltage threshold.
Above-mentioned earth leakage protective device, the zero sequence obtained when ac circuit occurs to leak electricity in circuit by zero sequence current mutual inductor
Electric current, is converted into voltage signal by leakage current processing unit by the current signal of zero sequence current mutual inductor, by micro-process
Device judges whether the voltage signal that leakage current processing unit exports is more than voltage threshold, if more than, send earth leakage protective and perform
Instruction, receives earth leakage protective by action execution unit and performs instruction rear cutout and break current supply circuit, by connecting microprocessor
Digital input interface arranges voltage threshold, it is possible to arrange residual current operating value flexibly, it is to avoid protection's dead-zone.
As a kind of preferred implementation of the present embodiment, as in figure 2 it is shown, leakage current processing unit includes that signal is changed
Subelement 21, seamless subelement 22 and amplification subelement 23.
Signal conversion subelement 21, its input is connected with the secondary side of zero sequence current mutual inductor, for by zero-sequence current
Signal is converted to voltage signal.
Preferably, signal conversion subelement 21 includes: be connected on the resistance R1 of the secondary side of zero sequence current mutual inductor, by zero
Sequence current signal is converted to the voltage signal at resistance R1 two ends, in order to the process of signal.Resistance R1 and diode D1, diode
D2 three is in parallel；The positive pole of diode D1 connects the negative pole of diode D2, and the negative pole of diode D1 connects the positive pole of diode D2.Work as electricity
When resistance R1 both end voltage is higher than the conducting voltage of diode D1 and D2, D1 or D2 is switched on, electric current be no longer flow through resistance R2 and
Subsequent conditioning circuit.Voltage clamp is carried out, to guarantee that the voltage of input microprocessor is not after amplified process by diode D1 and D2
Meeting is too high and microprocessor is caused damage.Resistance R1 two ends are also parallel with resistance R2 and electric capacity C1, resistance R2 and electric capacity C1 string
Connection, carries out capacitance compensation by electric capacity C1, can increase exciting current, and in the case of making zero-sequence current less, signal conversion is single
The output voltage of unit is unlikely to be too small so that in subsequent processes and can be left in the basket.
Seamless subelement 22, its input is connected with the outfan of signal conversion unit, for by sine voltage signal
Negative voltage transition becomes positive voltage.
Preferably, seamless subelement includes inverting amplifier OP1, and its negative input connects one end of resistance R3, resistance
The other end of R3 connects between resistance R2 and electric capacity C1；Its positive input ground connection.The output of inverting amplifier OP1 terminates two poles
The positive pole of pipe D3, the negative pole of diode D3 connects the negative sense of one end of resistance R4, the other end of resistance R4 and inverting amplifier OP1
Input connects.Inverting amplifier OP1 and resistance R3 and R4 constitutes see-saw circuit, the output voltage of inverting amplifier OP1
With input voltage relation be: Vout=(-R4/R3) * Vi, resistance R3 are identical with resistance R4 resistance, then Vout=-Vi i.e. passes through
Negative voltage transition in sine voltage signal is become positive voltage by seamless subelement.Voltage signal when signal conversion subelement output
For timing, owing to the outfan of inverting amplifier OP1 is negative, diode D3 can not turn on, therefore electric current directly through resistance R3 and
R4 flows to amplify subelement；When the voltage signal of signal conversion subelement output is for time negative, and inverted amplifier OP1 is just converted to
Voltage, thus diode D3 can be made to turn on, this negative voltage signal is just converted to positive voltage signal after seamless subelement
It is input to amplify subelement.
Amplifying subelement 23, its input is connected with the outfan of seamless subelement, for exported by seamless subelement
Voltage signal is amplified, and its outfan is connected with microprocessor.
Preferably, amplifying subelement and include operational amplifier OP2, its positive input connects the negative pole of diode D3, its
Negative input passes through resistance R5 ground connection, and its outfan connects one end of resistance R6, and the other end concatenation operation of resistance R6 is amplified
The negative input of device OP2；Electric capacity C2 is in parallel with resistance R6.Output voltage and the input voltage relation of this amplification subelement be:
Vout=(R5+R6)/R5*Vi.
Preferably, leakage current processing unit also includes: resistance R7, the outfan of its one end concatenation operation amplifier OP2,
The other end connects microprocessor；The other end ground connection of electric capacity C3, electric capacity C3 it is also associated with between resistance R7 and microprocessor.
As a kind of preferred implementation of the present embodiment, this earth leakage protective device also includes threephase current transformer and three
Phase current signal processing unit, threephase current transformer primary side connects ac circuit, and secondary side connects at three-phase current signal
Reason unit, the outfan of three-phase current signal processing unit connects embedded microprocessor；And/or, threephase potential transformer and
Three-phase voltage signal processing unit, threephase potential transformer primary side connects ac circuit, and secondary side connects three-phase voltage signal
Processing unit, the outfan of three-phase voltage signal processing unit connects embedded microprocessor.To realize mains side open-phase protection,
Prevent the phenomenon that three phase electric machine runs, motor burns out, collection overcurrent protection, short-circuit protection, phase voltage protection, residual current protecting
In one.
As a kind of preferred implementation of the present embodiment, this earth leakage protective device also includes display screen, is used for showing friendship
Flow back to the residual current on road.
As a kind of preferred implementation of the present embodiment, this earth leakage protective device also includes network communication unit, connects
Embedded microprocessor, for being transferred to host computer or remote monitoring terminal by the residual current of ac circuit, it is achieved remotely adjust
The voltage threshold of this earth leakage protective device whole, information inquiry, and download fault parameter.This network communication unit includes Ethernet
Communication module, GSM/GPRS communication module and RS-485 port.
Obviously, above-described embodiment is only for clearly demonstrating example, and not restriction to embodiment.Right
For those of ordinary skill in the field, can also make on the basis of the above description other multi-form change or
Variation.Here without also cannot all of embodiment be given exhaustive.And the obvious change thus extended out or
Change among the protection domain still in this utility model creation.
Claims (9)
1. an earth leakage protective device, it is characterised in that including:
Zero sequence current mutual inductor, its primary side connects ac circuit, when being used for obtaining the generation electric leakage of described ac circuit in circuit
Zero-sequence current；
Leakage current processing unit, connects the secondary side of described zero sequence current mutual inductor, for by described zero sequence current mutual inductor
The current signal of output is converted into voltage signal；
Embedded microprocessor, its input port connects the outfan of described leakage current processing unit, is used for judging described leakage
Whether the voltage signal of electricity current processing unit output is more than voltage threshold, if being more than, sending earth leakage protective and performing instruction；
Action execution unit, its input connects the outfan of described microprocessor, is used for receiving described earth leakage protective and performs
Described ac circuit is cut off after instruction；
Digital input interface, connects the user setup end of described microprocessor, is used for arranging described voltage threshold.
Earth leakage protective device the most according to claim 1, it is characterised in that described leakage current processing unit includes:
Signal conversion subelement, its input is connected with the secondary side of described zero sequence current mutual inductor, for being believed by zero-sequence current
Number be converted to voltage signal；
Seamless subelement, its input is connected with the outfan of described signal conversion unit, for bearing sine voltage signal
Voltage is converted into positive voltage；
Amplifying subelement, its input is connected with the outfan of described seamless subelement, for being exported by described seamless subelement
Voltage signal be amplified, its outfan is connected with described microprocessor.
Earth leakage protective device the most according to claim 2, it is characterised in that described signal conversion subelement includes: series connection
Resistance R1 at the secondary side of described zero sequence current mutual inductor；Described resistance R1 and diode D1, diode D2 three are in parallel；Institute
The positive pole stating diode D1 connects the negative pole of described diode D2, and the negative pole of described diode D1 connects the positive pole of described diode D2；
Described resistance R1 two ends are also parallel with resistance R2 and electric capacity C1, described resistance R2 and described electric capacity C1 series connection.
Earth leakage protective device the most according to claim 3, it is characterised in that described seamless subelement includes:
Inverting amplifier OP1, its negative input connects one end of resistance R3, and the other end of described resistance R3 connects described resistance
Between R2 and described electric capacity C1；Its positive input ground connection；The positive pole of its output terminating diode D3, described diode D3's is negative
Pole connects one end of resistance R4, and the other end of described resistance R4 is connected with the negative input of described inverting amplifier OP1；Described
Resistance R3 is identical with described resistance R4 resistance.
Earth leakage protective device the most according to claim 4, it is characterised in that described amplification subelement includes:
Operational amplifier OP2, its positive input connects the negative pole of described diode D3, and its negative input is connect by resistance R5
Ground, its outfan connects one end of resistance R6, and the other end of described resistance R6 connects the negative sense input of described operational amplifier OP2
End；Electric capacity C2 is in parallel with described resistance R6.
Earth leakage protective device the most according to claim 5, it is characterised in that described leakage current processing unit also includes:
Resistance R7, its one end connects the outfan of described operational amplifier OP2, and the other end connects described microprocessor；At described resistance
Electric capacity C3, the other end ground connection of described electric capacity C3 it is also associated with between R7 and described microprocessor.
Earth leakage protective device the most according to claim 1, it is characterised in that described device also includes:
Threephase current transformer and three-phase current signal processing unit, described threephase current transformer primary side connects described exchange
Loop, secondary side connects described three-phase current signal processing unit, and the outfan of described three-phase current signal processing unit connects
Described embedded microprocessor；
And/or,
Threephase potential transformer and three-phase voltage signal processing unit, described threephase potential transformer primary side connects described exchange
Loop, secondary side connects described three-phase voltage signal processing unit, and the outfan of described three-phase voltage signal processing unit connects
Described embedded microprocessor.
Earth leakage protective device the most according to claim 1, it is characterised in that described device also includes display screen, is used for showing
Show the residual current of described ac circuit.
9. according to the arbitrary described earth leakage protective device of claim 1 to 8, it is characterised in that described device also includes that network leads to
Letter unit, connects described embedded microprocessor, for the residual current of described ac circuit is transferred to host computer or long-range
Monitor terminal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620386472.XU CN205670677U (en) | 2016-04-29 | 2016-04-29 | A kind of earth leakage protective device |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620386472.XU CN205670677U (en) | 2016-04-29 | 2016-04-29 | A kind of earth leakage protective device |
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| CN205670677U true CN205670677U (en) | 2016-11-02 |
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| CN201620386472.XU Active CN205670677U (en) | 2016-04-29 | 2016-04-29 | A kind of earth leakage protective device |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107635005A (en) * | 2017-09-28 | 2018-01-26 | 河南汇纳科技有限公司 | A kind of improved earth leakage protective device |
| CN108931687A (en) * | 2018-04-27 | 2018-12-04 | 东南大学 | Household electric leakage real-time monitoring system based on Bluetooth communication |
-
2016
- 2016-04-29 CN CN201620386472.XU patent/CN205670677U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107635005A (en) * | 2017-09-28 | 2018-01-26 | 河南汇纳科技有限公司 | A kind of improved earth leakage protective device |
| CN108931687A (en) * | 2018-04-27 | 2018-12-04 | 东南大学 | Household electric leakage real-time monitoring system based on Bluetooth communication |
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Address after: 325604, No. 20-22, Heng Lu, Xinguang industrial district, Liushi Town, Yueqing, Zhejiang, Wenzhou Patentee after: Dry friend Technology Limited Address before: 325604, No. 20-22, Heng Lu, Xinguang industrial district, Liushi Town, Yueqing, Zhejiang, Wenzhou Patentee before: QIANLONG TECHNOLOGY CO., LTD. |