CN106371051B - A kind of high-voltage electric-energy meter current transformer leakage current removing method - Google Patents
A kind of high-voltage electric-energy meter current transformer leakage current removing method Download PDFInfo
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- CN106371051B CN106371051B CN201610846951.XA CN201610846951A CN106371051B CN 106371051 B CN106371051 B CN 106371051B CN 201610846951 A CN201610846951 A CN 201610846951A CN 106371051 B CN106371051 B CN 106371051B
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- 238000000034 method Methods 0.000 title claims abstract description 19
- 238000004804 winding Methods 0.000 claims abstract description 135
- 238000005070 sampling Methods 0.000 claims abstract description 9
- 238000006243 chemical reaction Methods 0.000 claims description 31
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 20
- 238000004891 communication Methods 0.000 claims description 17
- 230000005611 electricity Effects 0.000 claims description 11
- 230000005284 excitation Effects 0.000 claims description 11
- 229910052742 iron Inorganic materials 0.000 claims description 4
- 230000009977 dual effect Effects 0.000 claims description 2
- 239000000835 fiber Substances 0.000 claims 1
- 238000005259 measurement Methods 0.000 description 10
- 238000010586 diagram Methods 0.000 description 4
- 239000000654 additive Substances 0.000 description 2
- 230000000996 additive effect Effects 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000003990 capacitor Substances 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 230000001360 synchronised effect Effects 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 1
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- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R35/00—Testing or calibrating of apparatus covered by the other groups of this subclass
- G01R35/02—Testing or calibrating of apparatus covered by the other groups of this subclass of auxiliary devices, e.g. of instrument transformers according to prescribed transformation ratio, phase angle, or wattage rating
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R35/00—Testing or calibrating of apparatus covered by the other groups of this subclass
- G01R35/04—Testing or calibrating of apparatus covered by the other groups of this subclass of instruments for measuring time integral of power or current
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Measurement Of Current Or Voltage (AREA)
Abstract
The present invention provides a kind of high-voltage electric-energy meter current transformer leakage current removing methods, it is characterized by: making primary circuit and the secondary circuit equipotential of current transformer, to make the voltage zero between the primary circuit of current transformer and secondary circuit, achieve the purpose that electric current of stopping a leak, using the common voltage mutual inductor in biquadratic winding double-stage voltage transformer replacement high-voltage electric-energy meter;The present invention can carry out voltage, current synchronization sampling under high pressure equipotential state, so that the resistance to pressure request to current transformer reduces, can save the expense for purchasing high-tension current inductor;High-voltage electric-energy meter leakage current can be achieved to eliminate.
Description
Technical field
The present invention relates to a kind of high-voltage electric-energy meter current transformer leakage current removing methods, belong to Electric Measurement Technology
Field.
Background technique
High-voltage electric-energy meter sampling is related to the precise measurement to electric current, voltage value under high pressure conditions, general measure
Method be by mutual inductor by a high voltage, high current scaling transformation at convenient for measurement secondary voltage, after electric current again into
Row measurement (as shown in Figure 1), since the first winding and secondary winding of current transformer are insulation and are equably wound on same
On one magnetic core and the factors such as insulation quality, there can be certain point between first winding and secondary winding according to the principles of electric and electronic engineering
Cloth capacitor and leakage reactance will generate leakage current when applying working voltage between first winding and secondary winding, leakage electricity
Stream is superimposed with the formation of Current Transformer Secondary electric current, so that the measurement of electric current under high pressure conditions is generated additive error, is led to high-voltage electricity
It is capable of measuring inaccuracy.
Summary of the invention
The object of the present invention is in order to solve as application working voltage U between first winding and secondary windingeWhen will generate
Leakage current IX(Fig. 2), the leakage current are superimposed with the formation of Current Transformer Secondary electric current, make the measurement of electric current under high pressure conditions
Additive error is generated, high voltage electric energy measurement inaccuracy is caused.Needing to solve a critical issue --- electric current is mutual under high pressure conditions
The leakage current of sensor, that is, electric current of stopping a leak.The present invention provides a kind of leakages of high-voltage electric-energy meter current transformer
Electric current removing method.
The technical scheme adopted by the invention is that: a kind of high-voltage electric-energy meter current transformer leakage current elimination side
Method, it is characterised in that: make primary circuit and the secondary circuit equipotential of current transformer, so that the primary of current transformer be made to return
Voltage between road and secondary circuit is zero, achievees the purpose that electric current of stopping a leak.
Further preferably, using the common electricity in biquadratic winding double-stage voltage transformer replacement high-voltage electric-energy meter
Press mutual inductor;
The biquadratic winding double-stage voltage transformer TVG, including first order iron core, second level iron core, first order iron core
Side coiling excitation winding NL, coiling first winding N on the other side of first order iron core and second level iron core1And secondary winding
N2, secondary winding N3.Secondary winding N2It is with ground potential for the secondary winding referring to current potential, secondary winding N3For with primary voltage
High-voltage potential be referring to current potential secondary winding;Excitation winding NLHot end ALWith first winding N1Hot end A0
Connection, excitation winding NLCold end XLWith first winding N1Cold end X0Connection;Secondary winding N3Polar end 2n with
First winding N1Hot end A connection, secondary winding N3Non-polar end 2a be arranged in first winding N1Hot end A0One
Side;From first winding N1Hot end A0Draw A0Terminal, from secondary winding N3Non-polar end 2a draw 2a terminal;
Biquadratic winding double-stage voltage transformer TVGA0Terminal connects first winding non-polar end P2, biquadratic winding pair
The V of the 2a terminal connection voltage sample analog-digital conversion ic A/D1 of step voltage mutual inductorINEnd;
The present invention also provides a kind of high-voltage electric-energy meters, including biquadratic winding double-stage voltage transformer TVG, electricity
Current transformer TA, analog-digital conversion ic A/D1 and A/D2, central processor CPU, communication module, DC power supply, backstage PC;
The invention has the characteristics that:
(1) equipotential measurement electric current, voltage are made using current transformer primary circuit and secondary circuit equipotential method
The voltage of current transformer primary circuit and secondary circuit is zero, achievees the purpose that electric current of stopping a leak;(2) dual stage voltage is used
Mutual inductor replaces common voltage mutual inductor, and common voltage mutual inductor only has a secondary winding, and the present invention is retaining original one
On the basis of secondary winding, increase by one with primary voltage as two secondary windings referring to current potential;(3) electric current, voltage measurement list
Member is in high-voltage state, controls electric current, voltage measurement unit synchronized sampling by central processor CPU, CPU is by electric current, voltage
Synchronized sampling value is exported to communication module, is transmitted to the backstage PC in zero potential state by optical cable, wireless communication etc., is solved
The isolating problem of high voltage and the transmission of zero potential data;(4) high-voltage potential of primary voltage is designed as to the reference of measuring circuit
Current potential;(5) DC power supply is in high-voltage state, solves the isolating problem of high voltage and zero potential power supply.
The invention has the advantages that making electric current using current transformer primary circuit and secondary circuit equipotential method
Mutual inductor primary circuit is zero to the potential difference of secondary circuit, achievees the purpose that electric current of stopping a leak.To cooperate high pressure equipotential
Current sample operating mode carries out under the suitable high pressure equipotential state of the sampling of voltage, using biquadratic winding bipolar voltage mutual inductance
Device TVGReplace voltage transformer TV, biquadratic winding bipolar voltage mutual inductor TVGThe end 2A design close to primary voltage height
The A of piezoelectric position0Fig. 4, the analog quantity input V of A/D1 are seen in end sideinMeet biquadratic winding bipolar voltage mutual inductor TVG2A
End, the analog quantity input com of A/D1 meet biquadratic winding bipolar voltage mutual inductor TVGThe A of ratio winding0End realizes that voltage is surveyed
It measures unit and high pressure equipotential measures;This method to reduce the resistance to pressure request of current transformer, can save and purchase high pressure
The expense of current transformer;The above method can realize that high-voltage electric-energy meter leakage current is eliminated., warp succinct with method
Ji, scientific, practical, strong operability, it is at low cost the advantages that.
Detailed description of the invention
Fig. 1 is conventional high-pressure electric energy metering device schematic diagram;
Fig. 2 is that current transformer generates leakage current schematic diagram under high pressure conditions;
Fig. 3 is common bipolar voltage mutual inductor schematic diagram;
Fig. 4 is high-voltage electric-energy meter current transformer leakage current removing method schematic diagram;
Symbol in figure:
TV---- is voltage transformer;
A, X---- is respectively voltage transformer first winding hot end, cold end;
A, x---- is respectively secondary windings of PT hot end, cold end;
TA---- is current transformer;
P1、P2----be respectively current transformer first winding polar end, non-polar end;
S1、S2----be respectively secondary winding in current transformer polar end, non-polar end;
I1----be current transformer primary current;
I2----be Current Transformer Secondary electric current;
IX----be current transformer leakage current;
R2、R3----be respectively voltage transformer secondary output voltage divider resistance;
R---- is respectively the current/voltage-converted resistance of Current Transformer Secondary output;
TVG----be biquadratic winding double-stage voltage transformer;
NL----excitation winding;
N1----first winding;
N2、N3----secondary winding;
A0、X0----first winding hot end, cold end;
AL、XL----excitation winding hot end, cold end;
1a, 1n---- secondary winding N2Non-polar end, polar end;
2a, 2n---- secondary winding N3Non-polar end, polar end;
----primary voltage vector;
----secondary winding N2Voltage vector;
----secondary winding N3Voltage vector;
----excitation winding NLCurrent phasor;
----first winding N1Current phasor;
Inductive electric potential vector of ----first order mutual inductor;
----N1Inductive electric potential vector of the winding on two iron cores;
ZL----NLThe internal impedance of winding;
Z1----N1The internal impedance of winding;
Z′2Primary N is arrived in ----conversion2The internal impedance of winding;
Z′3Primary N is arrived in ----conversion3The internal impedance of winding;
Ym1The excitation admittance of ----first order mutual inductor;
Ym2The excitation admittance of ----second level mutual inductor;
Primary N is arrived in ----conversion2Winding voltage vector;
Primary N is arrived in ----conversion3Winding voltage vector;
A/D1, A/D2---- are respectively voltage, electric current analog-digital conversion ic;
VIN----be analog-digital conversion ic analog input end;
Com---- is integrated circuit common end;
Data bus---- is data/address bus;
CPU---- is high-pressure side central processing unit;
GND---- is common end;
V+----be DC power supply;
Vcc----be integrated circuit operation power input;
Z---- is current transformer once to the impedance between secondary winding;
DC power supply ----it is high-pressure side DC power supply;
Communication module ----it is the telecommunication circuits such as wireless;
Specific embodiment
Below in conjunction with attached drawing, the present invention is described in detail.
Usual electric energy measurement method is by a high voltage, high current scaling transformation by current transformer at convenient for survey
Secondary voltage, the electric current of amount, current transformer primary voltage, that is, working voltage Ue, secondary winding in current transformer polar end S1Or
Secondary winding in current transformer non-polar end S2It is grounded (see Fig. 2), if current transformer first winding is to Current Transformer Secondary
The voltage of winding is U1, current transformer first winding is Z to the capacitor and leakage reactance resultant impedance of secondary winding in current transformer,
Then leakage current IXAre as follows:
The present invention claims the primary circuits of current transformer and secondary circuit equipotential, when secondary winding is in the high electricity of operation
(see Fig. 4) when piezoelectric position, U1=0, then: IX=0, achieve the purpose that electric current of stopping a leak.
Using biquadratic winding double-stage voltage transformer TV as shown in Figure 4G, including first order iron core, second level iron core,
The side coiling excitation winding N of first order iron coreL, coiling first winding N on the other side of first order iron core and second level iron core1
With secondary winding N2, secondary winding N3.Secondary winding N2It is with ground potential for the secondary winding referring to current potential, secondary winding N3For
With the secondary winding that the high-voltage potential of primary voltage is referring to current potential.Excitation winding NLHot end ALWith first winding N1's
Hot end A0Connection, excitation winding NLCold end XLWith first winding N1Cold end X0Connection;Secondary winding N3's
Polar end 2n and first winding N1Hot end A connection, secondary winding N3Non-polar end 2a be arranged in first winding N1Height
Potential end A0Side.From first winding N1Hot end A0Draw A0Terminal, from first winding N1Cold end X0Draw X0
Terminal, from secondary winding N2Non-polar end 1a draw 1a terminal, from secondary winding N2Polar end 1n draw 1n terminal, from two
Secondary winding N3Non-polar end 2a draw 2a terminal.
As shown in figure 4, using the common electricity in biquadratic winding double-stage voltage transformer replacement high-voltage electric-energy meter
Mutual inductor is pressed, common voltage mutual inductor only has a secondary winding, and the present invention increases on the basis of retaining an original secondary winding
Add two secondary windings with primary voltage for reference current potential.The A of biquadratic winding double-stage voltage transformer0Terminal connection
First winding non-polar end P2, the integrated electricity of 2a terminal connection voltage sample analog-to-digital conversion of biquadratic winding double-stage voltage transformer
The V of road A/D1INEnd.
As shown in figure 4, one kind of the invention can eliminate electric current, the voltage sampling apparatus packet of current transformer leakage current
It includes: biquadratic winding double-stage voltage transformer TVG, current transformer TA, voltage sample analog-digital conversion ic A/D1 and electricity
Stream sampling analog-digital conversion ic A/D2, central processor CPU, communication module, DC power supply, backstage PC.
A kind of the step of high-voltage electric-energy meter current transformer leakage current removing method, is as follows:
1, the capital equipment that this method uses:
Biquadratic winding double-stage voltage transformer TVG, current transformer TA, voltage sample analog-digital conversion ic A/
D1, current sample analog-digital conversion ic A/D2, communication module, backstage PC;
2, central processor CPU passes through data/address bus data bus and voltage sample analog-digital conversion ic A/D1, electricity
The data port connection of stream sampling analog-digital conversion ic A/D2, central processor CPU pass through I/O mouthfuls and the I/O of communication module
Mouth connection;
3, communication module sends data to the backstage PC in zero potential state by optical cable, wireless communication etc.;
4, the end com of voltage sample analog-digital conversion ic A/D1, current sample analog-digital conversion ic A/D2
The end com, the end GND of central processor CPU, the end GND of DC power supply, TA S1And P2End, TVGA1And A0End with primary electricity
Press input terminal UHConnection;
5, resistance R1It is connected on bis- S of current transformer TA1End and S2Between end, current sample analog-digital conversion ic
The analog quantity input V of A/D2INWith bis- S of current transformer TA2End connection;
6, the analog quantity input V of voltage sample analog-digital conversion ic A/D1INIt is mutual with biquadratic winding bipolar voltage
Sensor TVGThe end 2A connection;
7, biquadratic winding bipolar voltage mutual inductor TVGX1End, X0End and primary voltage input terminal ULConnection;
8, the V of DC power supply+Terminate central processor CPU, voltage sample analog-digital conversion ic A/D1, current sample
The V of analog-digital conversion ic A/D2, communication moduleCCEnd;
The content that description in the present invention is not described in detail belongs to the well-known technique of professional and technical personnel in the field.
Claims (2)
1. a kind of high-voltage electric-energy meter current transformer leakage current removing method, it is characterised in that: make current transformer
Primary circuit and secondary circuit equipotential, to make the voltage between the primary circuit of current transformer and secondary circuit
Zero, achieve the purpose that electric current of stopping a leak;
Using biquadratic winding double-stage voltage transformer TVG, current transformer TA, voltage sample analog-digital conversion ic A/D1,
Current sample analog-digital conversion ic A/D2, communication module, backstage PC;
Using the common voltage mutual inductor in biquadratic winding double-stage voltage transformer replacement high-voltage electric-energy meter;
The biquadratic winding double-stage voltage transformer, including first order iron core, second level iron core, the side of first order iron core around
Excitation winding N processedL, coiling first winding N on the other side of first order iron core and second level iron core1With secondary winding N2, it is secondary around
Group N3;Secondary winding N2It is with ground potential for the secondary winding referring to current potential, secondary winding N3For with the high-voltage potential of primary voltage
For the secondary winding referring to current potential;Excitation winding NLHot end ALWith first winding N1Hot end A0Connection, excitation around
Group NLCold end XLWith first winding N1Cold end X0Connection;Secondary winding N3Polar end 2n and first winding N1's
Hot end A0Connection, secondary winding N3Non-polar end 2a be arranged in first winding N1Hot end A0Side;From once around
Group N1Hot end A0Draw A0Terminal, from secondary winding N3Non-polar end 2a draw 2a terminal;Biquadratic winding twin-stage electricity
Press the A of mutual inductor0Terminal connects first winding non-polar end P2, the 2a terminal of biquadratic winding double-stage voltage transformer connects electric
The signal input part V of pressure sampling analog-digital conversion ic A/D1IN;
Steps are as follows:
1, central processor CPU passes through data/address bus databus and voltage sample analog-digital conversion ic A/D1, current sample
The data port of analog-digital conversion ic A/D2 connects, and microprocessor CPU is connect by I/O mouthfuls with the I/O of communication module mouth;
2, communication module is wirelessly communicated with the backstage PC in zero potential state;
3, the end com of voltage sample analog-digital conversion ic A/D1, current sample analog-digital conversion ic A/D2 com
End, the end GND of central processor CPU, the end GND of DC power supply, current transformer TA S1End, biquadratic winding dual stage voltage
Mutual inductor TVGHot end A0With the first winding non-polar end P of current transformer TA2Connection;
4, resistance R is connected on secondary winding in current transformer polar end S1With secondary winding in current transformer non-polar end S2Between,
The analog quantity input V of current sample analog-digital conversion ic A/D2INWith secondary winding in current transformer non-polar end S2Even
It connects;
5, the analog quantity input V of voltage sample analog-digital conversion ic A/D1INWith biquadratic winding double-stage voltage transformer
TVGAnalog quantity input VINEnd connection;
6, biquadratic winding double-stage voltage transformer TVGExcitation winding NLCold end XLWith first winding N1Cold end
X0Connection;
7, the V of DC power supply+Terminate central processor CPU, voltage sample analog-digital conversion ic A/D1, current sample modulus
The integrated circuit operation power input V of converter ic A/D2, communication moduleCC。
2. high-voltage electric-energy meter current transformer leakage current removing method according to claim 1, feature exist
In: the communication module is fiber optic communications devices or wireless communication device.
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CN202735387U (en) * | 2012-07-21 | 2013-02-13 | 马任德 | Electric current transformer based on fiber vibration sensor |
CN103592491A (en) * | 2013-11-26 | 2014-02-19 | 国家电网公司 | Current isolation mutual inductor |
CN204332669U (en) * | 2014-12-26 | 2015-05-13 | 大连第一互感器有限责任公司 | High-voltage electric-energy meter integral combined transformer |
-
2016
- 2016-09-23 CN CN201610846951.XA patent/CN106371051B/en active Active
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3878455A (en) * | 1972-10-06 | 1975-04-15 | Philips Corp | Circuit arrangement for measuring the filament emission current of a cathode-ray or x-ray tube |
CN202735387U (en) * | 2012-07-21 | 2013-02-13 | 马任德 | Electric current transformer based on fiber vibration sensor |
CN103592491A (en) * | 2013-11-26 | 2014-02-19 | 国家电网公司 | Current isolation mutual inductor |
CN204332669U (en) * | 2014-12-26 | 2015-05-13 | 大连第一互感器有限责任公司 | High-voltage electric-energy meter integral combined transformer |
Non-Patent Citations (1)
Title |
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母线式电流互感器使用等电位线的机理;邢福全,谭艳华;《变压器》;20040131;第41卷(第1期);8,9 |
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