CN106526298B - A kind of zero sequence current measurement device and its mode of connection - Google Patents
A kind of zero sequence current measurement device and its mode of connection Download PDFInfo
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- CN106526298B CN106526298B CN201610851784.8A CN201610851784A CN106526298B CN 106526298 B CN106526298 B CN 106526298B CN 201610851784 A CN201610851784 A CN 201610851784A CN 106526298 B CN106526298 B CN 106526298B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/25—Arrangements for measuring currents or voltages or for indicating presence or sign thereof using digital measurement techniques
Abstract
The invention discloses a kind of zero sequence current measurement device and its mode of connection, flexible Application wiring is used for by connecting 5 connecting terminals outside device noumenon, independent zero-sequence current connection and synthesis zero-sequence current connection can be compatible with, and independent zero sequence current measurement and the synthesis ingenious combination of zero sequence current measurement share a zero sequence transformer, in the case where not changing device internal wiring, external different zero-sequence current cut-in method is adapted to completely, and there is powerful flexibility and adaptability.
Description
Technical field
The present invention relates to protecting electrical power system fields, and in particular to a kind of zero sequence current measurement device and its mode of connection.
Background technique
When single-phase earthing occurs for power distribution network, regulation regulation can be 2 hours with failure operation with ground；This is connect based on power distribution network
When earth-current is smaller, most of instantaneity ground arcs can be with self-extinguish, but if earth current is larger, single-phase earthing is electric
Arc sustained combustion will occur arc grounding over-voltage, or due to the thermal ionization and photo-ionisation of electric arc, can break ring surrounding air
Insulation, develop as phase fault accident, or even develop into " baked wheaten cake is operated " accident；So when distribution net work earthing fault occurs
When, the inspection of line being grounded is come out within a certain period of time, and is cut off within the regular hour；Then event is found
Hinder point, and is handled.
In power distribution network, zero-sequence current is the important means for reflecting ground fault；In the line, the phasor of three-phase current and
Equal to zero, i.e. Ia+Ib+Ic=0；If accessing a current transformer in the line, at this moment induced current is zero；When in circuit
When electric shock or leak current fault occurs, there is leakage current to flow through in circuit, at this moment pass through the three-phase current phasor of mutual inductor and differs
Zero, phasor and are as follows: Ia+Ib+Ic=I (leakage current, i.e. zero-sequence current)；Just there is a sense in mutual inductor secondary coil in this way
Electric current is answered, this electric current is applied to the electronic amplification circuit of detection part, compared with protection zone device predetermined action current value, if
Greater than action current, then sensitive relay is acted, acts on executive component tripping；Here the mutual inductor connect is known as zero sequence electricity
Current transformer, the phasor of three-phase current and be not equal to zero, generated electric current is zero-sequence current.
The mode of existing measurement zero-sequence current has several, but each way can only all match a device, Wu Faling
It is living to adapt to field demand；And the transformer parameter used is different, to the parameter with institute's Current Transformer in secondary device
Also it is not quite similar；It measures zero-sequence current and phase current circuit is also not quite similar;If wanting to change cut-in method, need to change in device
Portion's current transformer and corresponding circuits parameter, it is very cumbersome；It then must need to know in advance before order if necessary to protective device
The production method of road user's zero-sequence current；Then according to the production method of zero-sequence current, its corresponding device is produced for user
It uses；It delivers to after scene, if zero-sequence current production method need to be changed；Corresponding protective device cannot use, it is necessary to again
It orders.
Summary of the invention
The purpose of the invention is to provide it is a kind of can be flexible to adapt to scene compatible with independent zero sequence and synthesis zero sequence
Demand easily adjusts the zero sequence current measurement device and its mode of connection of zero sequence mode of connection at the scene.
The invention is realized by the following technical scheme: a kind of mode of connection of zero sequence current measurement device, including device sheet
Body, the neutral terminal being connect with device noumenon, A phase current connecting terminal, B phase current connecting terminal, C phase current connecting terminal and
Zero-sequence current connecting terminal；It is provided with self application route in described device ontology to connect with five connecting terminals, the self application
Route include the first current transformer, the second current transformer, third current transformer, zero sequence current mutual inductor, the first amplifier,
Second amplifier, third amplifier, four high guaily unit, first capacitor, the second capacitor, third capacitor, the 4th capacitor, first resistor, second
Resistance, 3rd resistor, the 4th resistance, the 5th resistance, the 6th resistance, the 7th resistance, the 8th resistance；First current transformer
The first pin be connected to A phase current connecting terminal, the first pin of second current transformer is connected to B phase current wiring
Terminal, the first pin of the third current transformer are connected to C phase current connecting terminal, and the of the zero sequence current mutual inductor
Two pins are connected to zero-sequence current connecting terminal；First current transformer, the second current transformer and third Current Mutual Inductance
The second pin of device and the first pin of zero sequence current mutual inductor are connected to neutral terminal；The of first current transformer
Three pins and the 4th pins in parallel have the 5th resistance, and the third pin of second current transformer and the 4th pins in parallel have
Six resistance, the third pin and the 4th pins in parallel of the third current transformer have the 7th resistance, the zero sequence current mutual inductance
The third pin and the 4th pins in parallel of device have the 8th resistance；The third pin of first current transformer is connected to the first fortune
4th pin of the negative input put, first current transformer is connected to the positive input of the first amplifier and connects
Ground；The third pin of second current transformer is connected to the negative input of the second amplifier, second current transformer
The 4th pin be connected to positive input and the ground connection of the second amplifier；The third pin of the third current transformer connects
To the negative input of third amplifier, the 4th pin of the third current transformer is connected to the positive input of third amplifier
And it is grounded；The third pin of the zero sequence current mutual inductor is connected to the negative input of four high guaily unit, the zero-sequence current
4th pin of mutual inductor is connected to positive input and the ground connection of four high guaily unit；The negative input of first amplifier and
First resistor and first capacitor are also parallel between output end, between the negative input and output end of second amplifier also simultaneously
Be associated with second resistance and the second capacitor, be also parallel between the negative input and output end of the third amplifier 3rd resistor and
Third capacitor is also parallel with the 4th resistance and the 4th capacitor between the negative input and output end of the four high guaily unit；It is described
First amplifier, the second amplifier, third amplifier and four high guaily unit output end be connected to sampling module；First amplifier,
The model LM324 of two amplifiers, third amplifier and four high guaily unit；5th resistance, the 6th resistance, the 7th resistance, the 8th electricity
Resistance is for being converted to voltage signal for current signal for current sampling.
A kind of zero sequence current measurement device mode of connection, the self application connection in device noumenon have neutral terminal, A phase
Current wiring terminal, B phase current connecting terminal, C phase current connecting terminal and zero-sequence current connecting terminal；
When using zero-sequenceprotection is synthesized:
Step a: three-phase current A, B, C are respectively connected to A phase current connecting terminal, B phase current connecting terminal, C phase current
Connecting terminal, and keep neutral terminal hanging；
Step b: three-phase current A, B, C pass through A phase current connecting terminal, B phase current connecting terminal, C phase current terminals
Son respectively enters the first current transformer, the second current transformer, third current transformer, then accesses in self application route
Internal current common end；
Step c: the internal current common end in self application route passes through zero sequence current mutual inductor and accesses zero-sequence current wiring
Terminal formed current loop, can by zero sequence current mutual inductor detect three-phase current A, B, C current phasor and；
Step d: three-phase current A, B, C become by the first current transformer, the second current transformer, third current transformer
Current signal is converted to by voltage signal by current sampling again after changing, is sent after then carrying out signal amplification filtering by amplifier
To sampling module, the electric current being calculated is the three-phase current of A, B, C；And pass through electricity again after converting by zero sequence current mutual inductor
Stream sampling, is converted to voltage signal for current signal, send after then carrying out signal amplification filtering by amplifier to sampling module, this
When the electric current that samples of sampling module be synthesis zero-sequence current；
When using independent zero-sequenceprotection:
Step a: accessing zero-sequence current connecting terminal for external zero-sequence current, by A, C biphase current in three-phase current point
It Jie Ru not A phase current connecting terminal and C phase current connecting terminal.The B phase current connecting terminal is hanging；
Step b: A, C biphase current in three-phase current pass through the first current transformer respectively and third current transformer connects
Onto the middle line connecting with neutral terminal, i.e., foreign current common end, external zero-sequence current pass through after zero sequence current mutual inductor
It is connected on the middle line being connect with neutral terminal；
Step c: A, C biphase current in three-phase current are after the first current transformer and the transformation of third current transformer
Again by current sampling, current signal is converted into voltage signal, then sent after signal amplification filters by amplifier to adopting
Egf block, the electric current being calculated are A, C biphase current in three-phase current；And external zero-sequence current passes through zero sequence current mutual inductance
Again by current sampling after device transformation, current signal is converted into voltage signal, signal amplification filtering is then carried out by amplifier
After send to sampling module, the electric current that sampling module samples at this time be independent zero-sequence current.
Preferably, sharing the same zero sequence transformer when using independent zero-sequenceprotection and using synthesis zero-sequenceprotection.
The present invention is used for flexible Application wiring by connecting 5 connecting terminals outside device noumenon, can be compatible with independent zero
Sequence electric current connection and synthesis zero-sequence current connection, and independent zero sequence current measurement and the synthesis ingenious combination of zero sequence current measurement share
One zero sequence transformer adapts to external different zero-sequence current access side in the case where not changing device internal wiring completely
Method has powerful flexibility and adaptability.
Compared with prior art, the invention has the beneficial effects that: 1) it is complete in the case where not changing device internal wiring
It is complete to adapt to external different zero-sequence current cut-in method, there is powerful flexibility and adaptability；2) device internal independence zero sequence
The processing method of protection and synthesis zero-sequenceprotection compatibility；3) practical, it is easy to maintain；4) at low cost, there is stronger market
Competitiveness.
Detailed description of the invention
Fig. 1 is the structural diagram of the present invention.
Fig. 2 is schematic diagram of the present invention using synthesis zero-sequenceprotection.
Fig. 3 is schematic diagram of the present invention using independent zero-sequenceprotection.
Specific embodiment
With reference to the accompanying drawing with specific embodiment, the invention will be further described.
See Fig. 1 to Fig. 3, a kind of mode of connection of zero sequence current measurement device, including device noumenon, is connect with device noumenon
Neutral terminal IN, A phase current connecting terminal IA, B phase current connecting terminal IB, C phase current connecting terminal IC and zero-sequence current
Connecting terminal I0；It is provided with self application route in described device ontology to connect with five connecting terminals, the self application route packet
Include the first current transformer, the second current transformer, third current transformer, zero sequence current mutual inductor, the first amplifier L1, second
Amplifier L2, third amplifier L3, four high guaily unit L4, first capacitor C1, the second capacitor C2, third capacitor C3, the 4th capacitor C4, first
Resistance R1, second resistance R2,3rd resistor R3, the 4th resistance R4, the 5th resistance R5, the 6th resistance R6, the 7th resistance R7, the 8th
Resistance R8；First pin of first current transformer is connected to A phase current connecting terminal IA, second current transformer
The first pin be connected to B phase current connecting terminal IB, the first pin of the third current transformer is connected to C phase current and connects
Line terminals IC, the second pin of the zero sequence current mutual inductor are connected to zero-sequence current connecting terminal I0；First electric current is mutual
First pin of sensor, the second pin of the second current transformer and third current transformer and zero sequence current mutual inductor all connects
To neutral terminal IN；The third pin and the 4th pins in parallel of first current transformer have a 5th resistance R5, and described second
The third pin and the 4th pins in parallel of current transformer have a 6th resistance R6, the third pin of the third current transformer and
4th pins in parallel has the 7th resistance R7, and the third pin and the 4th pins in parallel of the zero sequence current mutual inductor have the 8th resistance
R8；The third pin of first current transformer is connected to the negative input of the first amplifier L1, first Current Mutual Inductance
4th pin of device is connected to positive input and the ground connection of the first amplifier L1；The third pin of second current transformer
It is connected to the negative input of the second amplifier L2, the 4th pin of second current transformer is being connected to the second amplifier L2 just
To input terminal and it is grounded；The third pin of the third current transformer is connected to the negative input of third amplifier L3, institute
The 4th pin for stating third current transformer is connected to positive input and the ground connection of third amplifier L3；The zero-sequence current is mutual
The third pin of sensor is connected to the negative input of four high guaily unit L4, and the 4th pin of the zero sequence current mutual inductor is connected to
The positive input of four high guaily unit L4 and ground connection；It is also parallel between the negative input and output end of the first amplifier L1
First resistor R1 and first capacitor C1, is also parallel with second resistance between the negative input and output end of the second amplifier L2
R2 and the second capacitor C2, is also parallel with 3rd resistor R3 and third between the negative input and output end of the third amplifier L3
Capacitor C3, is also parallel with the 4th resistance R4 and the 4th capacitor C4 between the negative input and output end of the four high guaily unit L4；
The first amplifier L1, the second amplifier L2, third amplifier L3 and four high guaily unit L4 output end be connected to sampling module；It is described
The model LM324 of first amplifier L1, the second amplifier L2, third amplifier L3 and four high guaily unit L4；The 5th resistance R5, the 6th
Resistance R6, the 7th resistance R7, the 8th resistance R8 are used to current sampling current signal is converted to voltage signal.
In present embodiment, the self application connection in device noumenon has neutral terminal IN, A phase current connecting terminal
IA, B phase current connecting terminal IB, C phase current connecting terminal IC and zero-sequence current connecting terminal I0.
In present embodiment, when using zero-sequenceprotection is synthesized, three-phase current A, B, C step a: are respectively connected to A phase electricity
Connecting terminal IA, B phase current connecting terminal IB, C phase current connecting terminal IC are flowed, and makes neutral terminal IN hanging；
Step b: three-phase current A, B, C pass through A phase current connecting terminal, B phase current connecting terminal, C phase current terminals
Son respectively enters the first current transformer, the second current transformer, third current transformer, then accesses in self application route
Internal current common end；
Step c: the internal current common end in self application route passes through zero sequence current mutual inductor and accesses zero-sequence current wiring
Terminal formed current loop, can by zero sequence current mutual inductor detect three-phase current A, B, C current phasor and；
Step d: three-phase current A, B, C become by the first current transformer, the second current transformer, third current transformer
Current signal is converted to by voltage signal by current sampling again after changing, is sent after then carrying out signal amplification filtering by amplifier
To sampling module, the electric current being calculated is the three-phase current of A, B, C；And pass through electricity again after converting by zero sequence current mutual inductor
Stream sampling, is converted to voltage signal for current signal, send after then carrying out signal amplification filtering by amplifier to sampling module, this
When the electric current that samples of sampling module be synthesis zero-sequence current.
In present embodiment, when using independent zero-sequenceprotection: step a: external zero-sequence current access zero-sequence current being connect
A, C biphase current in three-phase current is respectively connected to A phase current connecting terminal IA and C phase current connecting terminal by line terminals I0
Middle line is accessed neutral terminal IN by IC, and the B phase current connecting terminal IB is hanging；
Step b: A, C biphase current in three-phase current pass through the first current transformer respectively and third current transformer connects
Onto the middle line connecting with neutral terminal IN, i.e., foreign current common end, external zero-sequence current pass through after zero sequence current mutual inductor
It is also coupled on the middle line being connect with neutral terminal IN；
Step c: A, C biphase current in three-phase current are after the first current transformer and the transformation of third current transformer
Again by current sampling, current signal is converted into voltage signal, then sent after signal amplification filters by amplifier to adopting
Egf block, the electric current being calculated are A, C biphase current in three-phase current；And external zero-sequence current passes through zero sequence current mutual inductance
Again by current sampling after device transformation, current signal is converted into voltage signal, signal amplification filtering is then carried out by amplifier
After send to sampling module, the electric current that sampling module samples at this time be independent zero-sequence current.
In present embodiment, the same zero-sequence mutual inductance is shared when using independent zero-sequenceprotection and using synthesis zero-sequenceprotection
Device；I.e. synthesis zero-sequence current is by the zero sequence on the internal current common end in self application route when using synthesis zero-sequenceprotection
What current transformer obtained, it and when using independent zero-sequenceprotection inner transformation handle and share a mutual inductor.
In present embodiment, it is by accessing one in outside line that independent zero-sequence current, which refers to directly measurement zero-sequence current,
A zero sequence current mutual inductor measures；Under normal circumstances, the phasor of three-phase current and it is equal to zero, i.e. at this moment Ia+Ib+Ic=0 incudes
Electric current is zero；When electric shock or leak current fault occur in circuit, there is leakage current to flow through in circuit, at this moment passes through the three of mutual inductor
Phase current phasor and not etc. zero, phasor and are as follows: the phasor of Ia+Ib+Ic=I leakage current three-phase current and be not equal to zero, produced
Raw electric current is independent zero-sequence current.This zero sequence is also known as " alone becoming zero sequence ".
In present embodiment, synthesis zero sequence is to calculate zero-sequence current by measuring ABC three-phase current；It is not needed outside
Zero sequence current mutual inductor is accessed in portion's route；The three-phase current vector of outside access is superimposed by portion in the device by calculating by it
It forms；The electric current obtained by this method is referred to as to synthesize zero-sequence current, and this zero sequence is also known as " synthesis zero sequence ".
In present embodiment, external A, B, C threephase current transformer range is generally 600/5,400/5,200/5；And zero
The range of sequence current transformer is generally 20/1；The two transformer parameter is different, cannot be mutually general；Similarly, to secondary
The parameter of institute's Current Transformer is also not quite similar in device；It measures zero-sequence current and phase current circuit is also not quite similar.
In present embodiment, when using independent zero-sequenceprotection, using 4 terminals, it is respectively as follows: A phase current connecting terminal
IA, C phase current connecting terminal IC, neutral terminal IN and zero-sequence current connecting terminal I0；Wherein, A phase current connecting terminal IA and C
Phase current connecting terminal IC is respectively connected to A, C biphase current, and zero-sequence current connecting terminal I0 accesses external zero-sequence current, middle line end
Sub- IN accesses foreign current common end, as middle line；: A phase current and C phase current pass through the first current transformer and third electric current
After mutual inductor, it is connected on the foreign current common end of neutral terminal IN；Zero-sequence current connecting terminal I0 then accesses external zero sequence electricity
Stream, external zero-sequence current are also connected on the foreign current common end of neutral terminal IN after running past zero sequence current mutual inductor；A
Phase current and C phase current are after the transformation of the first current transformer and third current transformer by being mainly made of amplifier
Logic circuit processing is sent to A/D using module samples, and the electric current being calculated is A phase current and C phase current；And external zero sequence electricity
Stream then send to A/D using the logic circuit processing being mainly made of four high guaily unit L4 after zero sequence current mutual inductor converts and adopts
Independent zero-sequence current is become using obtained electric current with module.
In present embodiment, when using synthesis zero-sequenceprotection, A phase current, B phase current and C phase current are respectively connected to A phase electricity
Connecting terminal IA, B phase current connecting terminal IB and C phase current connecting terminal IC are flowed, zero-sequence current connecting terminal I0 then accesses outer
Portion electric current common end, as middle line；A phase current, B phase current and C phase current pass through the first current transformer, the second Current Mutual Inductance
The internal current common end that adaptable line has just been accessed after device and third current transformer, then on internal current common end
It equipped with a zero sequence current mutual inductor, is detected using zero sequence current mutual inductor, the electricity of A phase current, B phase current and C phase current
Flow vector and, as zero-sequence current；And zero-sequence current wiring is accessed in internal current common end again after zero sequence current mutual inductor
Terminal I0, and its connection is foreign current common end, is formed a current loop；A phase current, B phase current and C phase electricity
Flow the logic after the first current transformer, the second current transformer and third current transformer by being mainly made of amplifier
It is sent after processing of circuit to A/D and is used using module, the electric current being calculated is A phase current, B phase current and C phase current；And this
When after zero sequence current mutual inductor converts using sending to A/D and adopt after the logic circuit processing being mainly made of four high guaily unit L4
With the electric current that module uses for synthesis zero-sequence current.
In present embodiment, synthesis zero-sequence current is converted through current transformer through logic by original three-phase current
A/D sampling is sent to be calculated after processing of circuit by software Vector modulation；But by three-phase current through internal phase current mutual inductor
Electric current common end is accessed afterwards, and zero sequence current mutual inductor is accessed on electric current common end, then send A/D to adopt after logic circuit is handled
Sample obtains；That is it synthesizes zero-sequence current and three-phase phase current is all to send A/D to sample to obtain after converting by current transformer；
Field demand can be flexibly adapted to, very easily adjusts zero sequence mode of connection at the scene.
Protection scope of the present invention includes but is not limited to embodiment of above, and protection scope of the present invention is with claims
Subject to, replacement, deformation, the improvement that those skilled in the art that any pair of this technology is made is readily apparent that each fall within of the invention
Protection scope.
Claims (4)
1. a kind of mode of connection of zero sequence current measurement device, it is characterised in that: including device noumenon, connect with device noumenon
Neutral terminal (IN), A phase current connecting terminal (IA), B phase current connecting terminal (IB), C phase current connecting terminal (IC) and zero
Sequence current wiring terminal (I0)；Self application route is provided in described device ontology to connect with five connecting terminals, it is described adaptive
It include the first current transformer, the second current transformer, third current transformer, zero sequence current mutual inductor, the first fortune with route
Put (L1), the second amplifier (L2), third amplifier (L3), four high guaily unit (L4), first capacitor (C1), the second capacitor (C2), third
Capacitor (C3), the 4th capacitor (C4), first resistor (R1), second resistance (R2), 3rd resistor (R3), the 4th resistance (R4),
Five resistance (R5), the 6th resistance (R6), the 7th resistance (R7), the 8th resistance (R8)；The first of first current transformer is drawn
Foot is connected to A phase current connecting terminal (IA), and the first pin of second current transformer is connected to B phase current connecting terminal
(IB), the first pin of the third current transformer is connected to C phase current connecting terminal (IC), the zero sequence current mutual inductor
Second pin be connected to zero-sequence current connecting terminal (I0)；First current transformer, the second current transformer and third
The second pin of current transformer and the first pin of zero sequence current mutual inductor are connected to neutral terminal (IN)；First electricity
The third pin and the 4th pins in parallel of current transformer have the 5th resistance (R5), the third pin of second current transformer and
4th pins in parallel has the 6th resistance (R6), and the third pin and the 4th pins in parallel of the third current transformer have the 7th electricity
It hinders (R7), the third pin and the 4th pins in parallel of the zero sequence current mutual inductor have the 8th resistance (R8)；First electric current
The third pin of mutual inductor is connected to the negative input of the first amplifier (L1), and the 4th pin of first current transformer connects
It is connected to the positive input of the first amplifier (L1) and ground connection；The third pin of second current transformer is connected to the second fortune
The negative input of (L2) is put, the 4th pin of second current transformer is connected to the positive input of the second amplifier (L2)
And it is grounded；The third pin of the third current transformer is connected to the negative input of third amplifier (L3), the third
4th pin of current transformer is connected to positive input and the ground connection of third amplifier (L3)；The zero sequence current mutual inductor
Third pin be connected to the negative input of four high guaily unit (L4), the 4th pin of the zero sequence current mutual inductor is connected to
The positive input of four high guaily unit (L4) and ground connection；Also parallel connection between the negative input and output end of first amplifier (L1)
There are first resistor (R1) and first capacitor (C1), is also parallel between the negative input and output end of second amplifier (L2)
Second resistance (R2) and the second capacitor (C2) are also parallel between the negative input and output end of the third amplifier (L3)
Three resistance (R3) and third capacitor (C3), are also parallel with the 4th between the negative input and output end of the four high guaily unit (L4)
Resistance (R4) and the 4th capacitor (C4)；First amplifier (L1), the second amplifier (L2), third amplifier (L3) and four high guaily unit
(L4) output end is connected to sampling module, and the self application connection in device noumenon has neutral terminal (IN), A phase current
Connecting terminal (IA), B phase current connecting terminal (IB), C phase current connecting terminal (IC) and zero-sequence current connecting terminal (I0)；
When using zero-sequenceprotection is synthesized, three-phase current A, B, C step a: are respectively connected to A phase current connecting terminal (IA), B phase
Current wiring terminal (IB), C phase current connecting terminal (IC), and make neutral terminal (IN) hanging；
Step b: three-phase current A, B, C are connect by A phase current connecting terminal (IA), B phase current connecting terminal (IB), C phase current
Line terminals (IC) respectively enter the first current transformer, the second current transformer, third current transformer, and access self application
Internal current common end in route；
Step c: the internal current common end in self application route passes through zero-sequence current connecting terminal by zero sequence current mutual inductor
(I0) it is connected with zero sequence current mutual inductor and forms current loop, three-phase current A, B, C can be detected by zero sequence current mutual inductor
Current phasor and；
Step d: three-phase current A, B, C are after the first current transformer, the second current transformer, the transformation of third current transformer
Again by current sampling, current signal is converted into voltage signal, then sent after signal amplification filters by amplifier to adopting
Egf block, the electric current being calculated are the three-phase current of A, B, C；And it is taken again by electric current after being converted by zero sequence current mutual inductor
Current signal is converted to voltage signal by sample, is sent after then carrying out signal amplification filtering by amplifier to sampling module, is adopted at this time
The electric current that egf block samples is synthesis zero-sequence current；
When using independent zero-sequenceprotection: step a: external zero-sequence current being accessed zero-sequence current connecting terminal (I0), by three-phase
A, C biphase current in electric current is respectively connected to A phase current connecting terminal (IA) and C phase current connecting terminal (IC), and middle line is connect
Enter neutral terminal (IN), the B phase current connecting terminal (IB) is hanging；
Step b: A, C biphase current in three-phase current pass through the first current transformer respectively and third current transformer be connected to
On the middle line of neutral terminal (IN) connection, i.e., foreign current common end, external zero-sequence current pass through after zero sequence current mutual inductor
It is connected on the middle line being connect with neutral terminal (IN)；
Step c: A, C biphase current in three-phase current lead to again after the first current transformer and the transformation of third current transformer
Overcurrent sampling, is converted to voltage signal for current signal, send after then carrying out signal amplification filtering by amplifier to sampling mould
Block, the electric current being calculated are A, C biphase current in three-phase current；And external zero-sequence current is become by zero sequence current mutual inductor
Current signal is converted to by voltage signal by current sampling again after changing, is sent after then carrying out signal amplification filtering by amplifier
To sampling module, the electric current that sampling module samples at this time is independent zero-sequence current.
2. a kind of mode of connection of zero sequence current measurement device according to claim 1, it is characterised in that: first fortune
Put the model LM324 of (L1), the second amplifier (L2), third amplifier (L3) and four high guaily unit (L4).
3. a kind of mode of connection of zero sequence current measurement device according to claim 1, it is characterised in that: the 5th electricity
(R5), the 6th resistance (R6), the 7th resistance (R7), the 8th resistance (R8) are hindered for by current sampling, current signal to be converted to
Voltage signal.
4. a kind of mode of connection of zero sequence current measurement device according to claim 1, it is characterised in that: use independent zero
Sequence is protected and shares the same zero sequence transformer using when synthesizing zero-sequenceprotection.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610851784.8A CN106526298B (en) | 2016-09-27 | 2016-09-27 | A kind of zero sequence current measurement device and its mode of connection |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201610851784.8A CN106526298B (en) | 2016-09-27 | 2016-09-27 | A kind of zero sequence current measurement device and its mode of connection |
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| Publication Number | Publication Date |
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| CN106526298A CN106526298A (en) | 2017-03-22 |
| CN106526298B true CN106526298B (en) | 2019-02-15 |
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| CN201610851784.8A Active CN106526298B (en) | 2016-09-27 | 2016-09-27 | A kind of zero sequence current measurement device and its mode of connection |
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| CN110112712B (en) * | 2019-04-30 | 2021-08-03 | 广东电网有限责任公司 | Power distribution network grounding protection device with double-transformer configuration and sampling control method thereof |
| CN116148521B (en) * | 2023-04-14 | 2023-07-14 | 烟台东方威思顿电气有限公司 | High-voltage metering device and depth fusion type polar column |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2710223Y (en) * | 2004-04-09 | 2005-07-13 | 北京航空航天大学 | Microcomputer protection device of terminal user switch cubicle with power supple |
| CN1744405A (en) * | 2005-09-16 | 2006-03-08 | 广东珠江开关有限公司 | Intelligent self-learning motor protective circuit breaker |
| CN103364627A (en) * | 2013-07-15 | 2013-10-23 | 长城电器集团有限公司 | Leakage current detection circuit of automatic reclosing lock disconnector |
| CN203746656U (en) * | 2014-03-03 | 2014-07-30 | 天水长开互感器制造有限公司 | Three-phase anti-resonance voltage transformer |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2710223Y (en) * | 2004-04-09 | 2005-07-13 | 北京航空航天大学 | Microcomputer protection device of terminal user switch cubicle with power supple |
| CN1744405A (en) * | 2005-09-16 | 2006-03-08 | 广东珠江开关有限公司 | Intelligent self-learning motor protective circuit breaker |
| CN103364627A (en) * | 2013-07-15 | 2013-10-23 | 长城电器集团有限公司 | Leakage current detection circuit of automatic reclosing lock disconnector |
| CN203746656U (en) * | 2014-03-03 | 2014-07-30 | 天水长开互感器制造有限公司 | Three-phase anti-resonance voltage transformer |
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Denomination of invention: A zero sequence current measuring device and its wiring method Effective date of registration: 20220214 Granted publication date: 20190215 Pledgee: Agricultural Bank of China Limited Ningbo Yinzhou Branch Pledgor: Ningbo Sanxing Smart Electric Co.,Ltd. Registration number: Y2022330000213 |
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