CN206609911U - Current transformer on-line testing system based on new pincerlike Rogowski coil - Google Patents
Current transformer on-line testing system based on new pincerlike Rogowski coil Download PDFInfo
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- CN206609911U CN206609911U CN201720144682.2U CN201720144682U CN206609911U CN 206609911 U CN206609911 U CN 206609911U CN 201720144682 U CN201720144682 U CN 201720144682U CN 206609911 U CN206609911 U CN 206609911U
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Abstract
Current transformer on-line testing system based on new pincerlike Rogowski coil, including new pincerlike Rogowski coil sensing head, Wireless Transmitter, signal pass through analysis module, host computer.The new pincerlike Rogowski coil sensing head includes two pieces of pcb boards, pincerlike Rogowski coil, radome, and two pieces of pcb boards are with pincerlike Rogowski coil fixed placement in radome.Two pieces of pcb board planes are vertical with pincerlike Rogowski coil plane, when coil tight close, two pieces of pcb boards are parallel, and the extended line of two pieces of pcb boards draws a straight line by hub of a spool, first piece of pcb board PCB1 be fixed on pincerlike 135 ° of places of Rogowski coil left semicircle centerlines, second piece of pcb board PCB2 be fixed on at 45 ° of pincer Rogowski coil right semi-circle centerlines.Pincerlike Rogowski coil connects signal by connecting line and passes through analysis module.The utility model realizes the self diagnosis of device itself degree of accuracy when substation field is measured, so as to ensure that accuracy of measurement, overcomes the easy by the problem of opening size of gaps is influenceed, the degree of accuracy is not high of conventional clamp on amperemeter method presence.
Description
Technical field
The utility model is related to power system measuring field, and in particular to a kind of based on new pincerlike Rogowski coil
Current transformer on-line testing system.
Background technology
At present, whether the verification of traditional transformer or electronic mutual inductor all rests on offline checking stage, lacks
The effective means that can be monitored in the energized state to transformer, and lack corresponding verification specification, so as to limit
The raising of transformer and perfect, also constrains its popularization and application in digital transformer substation.Current electronic mutual inductor is existing
It is general during the verification of field to use electromagnetic current transducer as standard current transformer, standard used in existing field-checking
Transformer volume is big, weight heavy, dynamic range is small, is unfavorable for execute-in-place.During current transducer check, it usually needs to circuit
Have a power failure, cause checking procedure sufficiently complex, bring inconvenience to electric company and user, and be unfavorable for transformer to greatest extent
Utilization.Therefore the online Real-time Error verification to transformer is particularly important.
Rogowski coil is as a kind of current sensor, due to small volume, lightweight, measurement bandwidth, dynamic
The characteristics of scope is big, can be used as standard current transformer, it is possible to achieve to current transformer using pincerlike Rogowski coil
Powered installation and verification.But easily there is opening air gap in pincerlike Rogowski coil, influence measurement accuracy in installation process,
Therefore the opening air gap self calibration of pincerlike Rogowski coil is Research Challenges.
The content of the invention
In order to solve the above technical problems, a kind of electric current based on new pincerlike Rogowski coil of the utility model offer is mutual
Sensor on-line testing system, due to using air gap self calibration mode, device itself is realized when substation field is measured accurate
The self diagnosis of degree, so as to ensure that accuracy of measurement, overcomes the easy by opening size of gaps of conventional clamp on amperemeter method presence
Influence, the problem of the degree of accuracy is not high.The system has small volume, lightweight, advantages of simple structure and simple, and the degree of accuracy is up to 0.05
Level, mobility is strong during onsite application.Meanwhile, the data of new pincerlike Rogowski coil opening air gap self-calibration process are passed through
Radio transmitting device is transmitted, separate with checking procedure data channel, can be retained separately, in order to go deep into mining analysis, is protected
The independence of data is demonstrate,proved.
The technical scheme that the utility model is taken is：
A kind of new pincerlike Rogowski coil sensing head, including two pieces of pcb boards, pincerlike Rogowski coil, radomes,
Two pieces of pcb boards are with pincerlike Rogowski coil fixed placement in radome.Two pieces of pcb board planes and pincerlike Rogowski coil
Plane is vertical, and when coil tight close, two pieces of pcb boards are parallel, and the extended line of two pieces of pcb boards is linked to be one by hub of a spool
Bar straight line, first piece of pcb board PCB1 be fixed on at pincerlike 135 ° of Rogowski coil left semicircle centerlines, second piece
Pcb board PCB2 be fixed on at pincerlike 45 ° of Rogowski coil right semi-circle centerlines.
Current transformer on-line testing system based on new pincerlike Rogowski coil, including new pincerlike Rogowski
Coil sensing head, Wireless Transmitter, signal pass through analysis module, host computer.The new pincerlike Rogowski coil sensing head
Including two pieces of pcb boards, pincerlike Rogowski coil, radome, two pieces of pcb boards are with pincerlike Rogowski coil fixed placement in screen
Cover in cover.Two pieces of pcb board planes are vertical with pincerlike Rogowski coil plane, when coil tight close, and two pieces of pcb boards are put down
OK, and the extended lines of two pieces of pcb boards draws a straight line by hub of a spool, first piece of pcb board PCB1 be fixed on it is pincerlike
At 135 ° of Rogowski coil left semicircle centerlines, second piece of pcb board PCB2 is fixed on right with pincerlike Rogowski coil
At 45 ° of semicircle centerlines.Pincerlike Rogowski coil connects signal by analysis module by connecting line, and signal is by dividing
The tested current transformer of module connection is analysed, signal connects host computer by analysis module.Wireless Transmitter is positioned over outside radome
Side surface, Wireless Transmitter is connected by connecting line with two pieces of pcb boards.
The pcb board size is 7cm × 7cm, is dual platen, there is the wire of 5 circles from inside to outside on each face, and pcb board is thick
Spend 1.6mm.
The pincerlike Rogowski coil thickness is 6mm, and internal diameter is 64mm, and external diameter is 84mm, and the number of turn is 600.
A kind of current transformer on-line testing method, after new pincerlike Rogowski coil sensing head installation, enters
Row opening air gap self calibration, self calibration mode is：First piece of pcb board PCB1 and second piece of pcb board PCB2 passes through output electricity of connecting
Signal is pressed, is gathered via high-side signal collecting unit and is transferred to low-side signal processing unit, in signal processing unit
Signal is amplified, and completes voltage and the function conversion of opening size of gaps, operating personnel are according to opening size of gaps, to passing
Sense head is clamped operation.
A kind of current transformer on-line testing method, pincerlike Rogowski coil and two pieces of pcb board foldings, two pieces simultaneously
Angle between angle between pcb board and pincerlike Rogowski coil or so semicircle is identical.
A kind of current transformer on-line testing method, during new pincerlike Rogowski coil sensing head coil tight close,
First piece of pcb board PCB1, second piece of pcb board PCB2 are connected in alignment, and series connection output voltage is approximately 0, when coil closure
When less closely there is opening air gap, first piece of pcb board PCB1, second piece of pcb board PCB2 have certain angle, series connection output
Voltage increases, voltage exponent function relation approximate with opening size of gaps.
A kind of current transformer on-line testing method, first block of pcb board PCB1, second block of pcb board PCB2 series connection output electricity
Pressure amount, far-end receiver is transferred to by Wireless Transmitter, carries out opening size of gaps conversion, and carry out pincer by operator
The adjustment of Rogowski coil opening air gap.
A kind of current transformer on-line testing system based on new pincerlike Rogowski coil of the utility model, technology effect
Fruit is as follows：
1), according to the non-linear relation between two pieces of pcb board series voltage outputs and coil aperture air gap, biography is being installed
Feel after head, opening size of gaps is judged according to the output of PCB series voltages first, if opening air gap is more than some threshold value,
Coil aperture is clamped, until opening air gap is less than the threshold value, pincerlike Rogowski coil tight close.Based on above-mentioned side
The opening air gap self calibration of formula so that the measurement process of pincerlike Rogowski coil is not influenceed by opening air gap, measurement is accurate
Degree is improved.
2), the data of new pincerlike Rogowski coil opening air gap self-calibration process, are transmitted by radio transmitting device,
It is separate with checking procedure data channel, it can be retained separately, in order to go deep into mining analysis, it is ensured that the independence of data.
3), new pincerlike Rogowski coil sensing head small volume, lightweight, gross weight is no more than 2kg, easy to operate letter
Single, 0~100A of measurement range, the degree of accuracy reaches 0.05 grade, is especially suitable for substation field and uses.
4), pincerlike Rogowski coil and two pieces of pcb boards are positioned in radome, anti-interference when substation field is used
Ability is strong.
Brief description of the drawings
Fig. 1 is the utility model system connection diagram.
Fig. 2 (a) is the graph of a relation between pincerlike Rogowski coil output amplitude of the present utility model and opening air gap.
Fig. 2 (b) is the graph of a relation between pincerlike Rogowski coil output phase of the present utility model and opening air gap.
When Fig. 3 (a) is coil tight close of the present utility model, two pieces of pcb board locations drawing.
When Fig. 3 (b) is that coil of the present utility model has opening air gap, two pieces of pcb board position views.
Fig. 4 is two pieces of pcb boards wired in series schematic diagram of the present utility model.
Fig. 5 is pincerlike Rogowski coil output voltage of the present utility model exponent function relation approximate with opening size of gaps
Figure.
Wherein, mark 4 represents two pieces of pcb board wired in series.
Embodiment
Principle analysis：
Pincerlike Rogowski coil is influenceed as current transformer, its measurement accuracy by opening air gap, coil output
Amplitude variable quantity increases and increased with opening air gap, and in the range of 1mm opening air gaps, amplitude variable quantity reaches 0.2%.In order to right
Coil carries out opening air gap calibration, and the utility model places two pieces of pcb boards in pincerlike Rogowski coil ad-hoc location, and line
Enclose plane vertical, and when coil tight close, two pieces of pcb boards into parallel, and two boards extended line by hub of a spool company
It is in alignment.By detecting the output quantity of pcb board, two pcb boards series connection output voltage amount is transferred to by Wireless Transmitter 6
Distal end based on C8051F single-chip microcomputers receives measure and control device, carries out opening size of gaps conversion, indicates operator to pincerlike coil
Opening air gap is adjusted, so as to realize the air gap self calibration of pincerlike Rogowski coil.
New pincerlike Rogowski coil can realize the self calibration of split implication gap before the mounting, substantially increase standard
The verification degree of accuracy of current transformer.The acquired unit collection of the sensing head output signal after self calibration is carried out, is transmitted by signal
Unit transmits the merging and processing that signal is carried out to low-side signal processing unit, so as to carry out on-line testing.
First choice, the utility model provides a kind of new pincerlike Rogowski coil sensing head, including two pieces of pcb boards 2, pincers
Rogowski coil 1, radome 3, two pieces of pcb boards 2 are with the pincerlike fixed placement of Rogowski coil 1 in radome 3.Two pieces
Pcb board plane is vertical with the pincerlike plane of Rogowski coil 1, and when coil tight close, two pieces of pcb boards are parallel, and two pieces of PCB
The extended line of plate draws a straight line by hub of a spool, and first piece of pcb board PCB1 is fixed on left with pincerlike Rogowski coil 1
At 135 ° of semicircle centerlines, second piece of pcb board PCB2 is fixed on and the pincerlike right semi-circle centerlines of Rogowski coil 1
At 45 °.
Secondly, the utility model provides a kind of current transformer on-line testing system based on new pincerlike Rogowski coil
System, as shown in figure 1, including new pincerlike Rogowski coil sensing head, Wireless Transmitter 6, signal by analysis module 8, on
Position machine 10.
The new pincerlike Rogowski coil sensing head includes two pieces of pcb boards 2, pincerlike Rogowski coil 1, radome
3, two pieces of pcb boards 2 are with the pincerlike fixed placement of Rogowski coil 1 in radome 3.Two pieces of pcb board planes and pincer
The plane of Rogowski coil 1 is vertical, and when coil tight close, two pieces of pcb boards are parallel, and the extended line of two pieces of pcb boards passes through
Hub of a spool is drawn a straight line, and first piece of pcb board PCB1 is fixed on and the pincerlike left semicircle centerlines of Rogowski coil 1
At 135 °, second piece of pcb board PCB2 be fixed on at pincerlike 45 ° of 1 right semi-circle centerlines of Rogowski coil.It is pincerlike
Rogowski coil 1 and tested current transformer 7 are connected to signal by analysis module 8 by connecting line 5, and signal passes through analysis
Module 8 connects host computer 10.
Wireless Transmitter 6 is positioned over the outer surface of radome 3, and Wireless Transmitter 6 passes through connecting line and two pieces of phases of pcb board 2
Connection.
Signal realizes the analysis and processing of signal by analysis module 8 using the FPGA of EPF10K series.
The pcb board size is 7cm × 7cm, is dual platen, there is the wire of 5 circles from inside to outside on each face, and pcb board is thick
Spend 1.6mm.To pcb board parameter reference literature《The calculating of board plug type PCBRogowski coils and emulation _ Wang Liming》In emulation
Parameter is configured.Because pcb board wiring and size directly influence pcb board self-induction and mutual inductance, mutual inductance increase meeting
Electrodynamic capacity is caused to increase, electrodynamic capacity increase can influence frequency band and angular difference.In order to obtain high-precision pcb board cascaded structure,
The coordination of self-induction and mutual inductance is taken into account simultaneously, and the utility model has carried out arrangement above to parameter.Pcb board parameter described above
The high accuracy of pcb board cascaded structure is ensured, while taking into account the coordination of self-induction and mutual inductance.
The thickness of pincerlike Rogowski coil 1 is 6mm, and internal diameter is 64mm, and external diameter is 84mm, and the number of turn is 600.
Pincerlike Rogowski coil internal-and external diameter in the utility model is set can be on the basis of insulation distance be met, to the greatest extent
Amount reduces electrodynamic capacity, so as to reduce the influence caused in measurement process to frequency band and angular difference；The quantity increase of wire turn, coil is mutual
Feel coefficient increase, but as quantity gradually increases, coil mutual inductance coefficient gathers way more and more slower, it is therefore desirable to selection is suitable
The number of turn ensure the precision in coil measurement process, what the coil turn set by the utility model disclosure satisfy that the above will
Ask.
The internal-and external diameter of pincerlike Rogowski coil 1, which is set, to be reduced as far as possible certainly on the basis of insulation distance is met
Coefficient is felt, so as to reduce the influence that diagonal difference in measurement process is caused；The quantity increase of wire turn, the increase of coil mutual inductance coefficient, but
It is that coil mutual inductance coefficient gathers way more and more slower as quantity gradually increases, it is therefore desirable to select the suitable number of turn to ensure
Precision in coil measurement process, the coil turn set by the utility model disclosure satisfy that the requirement of the above.
A kind of current transformer on-line testing method, after new pincerlike Rogowski coil sensing head installation, enters
Row opening air gap self calibration, self calibration mode is：First piece of pcb board PCB1 and second piece of pcb board PCB2 passes through output electricity of connecting
Signal is pressed, is gathered via wireless transmissions device 6 and is transferred to the distal end reception measure and control device 8 based on C8051F single-chip microcomputers, in signal
Signal is amplified in processing unit, and completes voltage and the function conversion of opening size of gaps, operating personnel are according to opening gas
Gap size, operation is clamped to new pincerlike Rogowski coil sensing head.
A kind of current transformer on-line testing method, during new pincerlike Rogowski coil sensing head coil tight close,
First piece of pcb board PCB1, second piece of pcb board PCB2 are connected in alignment, and series connection output voltage is approximately 0, when coil closure
When less closely there is opening air gap, first piece of pcb board PCB1, second piece of pcb board PCB2 have certain angle, series connection output
Voltage increases, voltage exponent function relation approximate with opening size of gaps.
A kind of current transformer on-line testing method, first block of pcb board PCB1, second block of pcb board PCB2 series connection output electricity
Pressure amount, is transferred to the distal end based on C8051F single-chip microcomputers by Wireless Transmitter 6 and receives measure and control device, carry out opening size of gaps
Conversion, and by the adjustment of the pincerlike Rogowski coil opening air gap of operator's progress.
Relation such as Fig. 2 (a), Fig. 2 (b) institutes between the pincerlike output amplitude of Rogowski coil 1 and phase and opening air gap
Show.As can be seen that with the increase of opening air gap, the pincerlike amplitude of Rogowski coil 1 change increases towards negative direction, phase place change
In spite of the trend of increase, but change very small, phase place change is less than 0.001 point, it is believed that be constant.Therefore it is open
The presence of air gap influences larger to the pincerlike measurement error of Rogowski coil 1.For the opening gas to pincerlike Rogowski coil 1
Gap is adjusted, and the utility model is using two pieces of pcb board monitoring opening air gaps, ad-hoc location such as Fig. 3 (a), Fig. 3 (b) of pcb board
It is shown.Fig. 4 illustrates two pieces of series wiring situations of pcb board 2.As can be seen that when pincerlike 1 tight close of Rogowski coil,
Two pieces of pcb board extended lines are in alignment, from the figure 3, it may be seen that two pcb boards series connection output voltage is approximately 0, when coil is closed less
Closely, when there is opening air gap, two pieces of pcb boards have certain angle, series connection output voltage increase.Voltage and opening air gap are big
Small approximate exponent function relation, as shown in Figure 5.Therefore size of gaps can be judged using pcb board series connection output, so that real
The now adjustment of opening air gap.
Closed as Fig. 3 (a) and Fig. 3 (b) respectively show two pieces of pcb board planes with the online trap of pincerlike Rogowski coil 1
Relative position relation close and when there is opening air gap.Two pieces of pcb board planes are vertical with pincerlike Rogowski coil plane, the
One piece of pcb board PCB1 is fixed on and at pincerlike 135 ° of coil left semicircle centerlines, second piece of pcb board PCB2 is fixed on and clamped
At 45 ° of shape coil right semi-circle centerlines.
Signal is used to receive tested current transformer 7 by analysis module 8 and the pincerlike two-way of Rogowski coil 1 output is believed
Number, analyzed and processed.Signal analysis module 8 refers to realizing the analysis and processing of signal using the FPGA of EPF10K series
Device.
Pincerlike Rogowski coil 1, two pieces of pcb boards, radome 3 and Wireless Transmitter 6 constitute a new pincer
Rogowski coil sensing head is overall.
Current transformer on-line testing system of the utility model based on new pincerlike Rogowski coil, side simple to operate
Just, the degree of accuracy, up to 0.05 grade, is especially suitable for substation field and used in 0~100A measurement ranges.
Claims (4)
1. a kind of new pincerlike Rogowski coil sensing head, it is characterised in that：Including two pieces of pcb boards (2), pincer Rogowski
Coil (1), radome (3), two pieces of pcb boards (2) are with pincerlike Rogowski coil (1) fixed placement in radome (3)；Two pieces
Pcb board plane is vertical with pincerlike Rogowski coil (1) plane, and when coil tight close, two pieces of pcb boards are parallel, and two pieces
The extended line of pcb board is drawn a straight line by hub of a spool, and first piece of pcb board is fixed on and pincerlike Rogowski coil (1)
At 135 ° of left semicircle centerlines, second piece of pcb board is fixed on and pincerlike Rogowski coil (1) right semi-circle centerlines
At 45 °.
2. the current transformer on-line testing system based on new pincerlike Rogowski coil, including new pincerlike Rogowski lines
Circle sensing head, Wireless Transmitter (6), signal pass through analysis module (8), host computer (10), it is characterised in that：The new pincer
Rogowski coil sensing head includes two pieces of pcb boards (2), pincerlike Rogowski coil (1), radome (3), two pieces of pcb boards (2)
With pincerlike Rogowski coil (1) fixed placement in radome (3)；Two pieces of pcb board planes and pincerlike Rogowski coil (1)
Plane is vertical, and when coil tight close, two pieces of pcb boards are parallel, and the extended line of two pieces of pcb boards is linked to be one by hub of a spool
Bar straight line, first piece of pcb board be fixed on at pincerlike 135 ° of Rogowski coil (1) left semicircle centerlines, second piece of PCB
Plate be fixed on at pincerlike 45 ° of Rogowski coil (1) right semi-circle centerlines；Pincerlike Rogowski coil (1) passes through even
Wiring (5) connects signal by analysis module (8), and signal connects tested current transformer (7), signal by analysis module (8)
Host computer (10) is connected by analysis module (8)；Wireless Transmitter (6) is positioned over radome (3) outer surface, Wireless Transmitter
(6) it is connected by connecting line with two pieces of pcb boards (2).
3. the current transformer on-line testing system based on new pincerlike Rogowski coil according to claim 2, it is special
Levy and be：Pcb board size is 7cm × 7cm, is dual platen, there is the wire of 5 circles from inside to outside, pcb board thickness on each face
1.6mm。
4. the current transformer on-line testing system based on new pincerlike Rogowski coil according to claim 2, it is special
Levy and be：Pincerlike Rogowski coil (1) thickness is 6mm, and internal diameter is 64mm, and external diameter is 84mm, and the number of turn is 600.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720144682.2U CN206609911U (en) | 2017-02-17 | 2017-02-17 | Current transformer on-line testing system based on new pincerlike Rogowski coil |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720144682.2U CN206609911U (en) | 2017-02-17 | 2017-02-17 | Current transformer on-line testing system based on new pincerlike Rogowski coil |
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| Publication Number | Publication Date |
|---|---|
| CN206609911U true CN206609911U (en) | 2017-11-03 |
Family
ID=60169236
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201720144682.2U Expired - Fee Related CN206609911U (en) | 2017-02-17 | 2017-02-17 | Current transformer on-line testing system based on new pincerlike Rogowski coil |
Country Status (1)
| Country | Link |
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| CN (1) | CN206609911U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106645861A (en) * | 2017-02-17 | 2017-05-10 | 三峡大学 | Online verifying system for current transformer based on novel pincer-like Rogowski coil |
| CN109669090A (en) * | 2019-02-25 | 2019-04-23 | 云南电网有限责任公司红河供电局 | Anti- defect diagnostic method is done in a kind of operation monitored based on carrier general branch electric current and neutral point voltage |
| CN111141972A (en) * | 2019-12-16 | 2020-05-12 | 西安交通大学 | Capacitor running state online monitoring method based on PCB Rogowski coil |
-
2017
- 2017-02-17 CN CN201720144682.2U patent/CN206609911U/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106645861A (en) * | 2017-02-17 | 2017-05-10 | 三峡大学 | Online verifying system for current transformer based on novel pincer-like Rogowski coil |
| CN106645861B (en) * | 2017-02-17 | 2020-11-10 | 三峡大学 | Online current transformer checking system based on pincerlike Rogowski coil |
| CN109669090A (en) * | 2019-02-25 | 2019-04-23 | 云南电网有限责任公司红河供电局 | Anti- defect diagnostic method is done in a kind of operation monitored based on carrier general branch electric current and neutral point voltage |
| CN111141972A (en) * | 2019-12-16 | 2020-05-12 | 西安交通大学 | Capacitor running state online monitoring method based on PCB Rogowski coil |
| CN111141972B (en) * | 2019-12-16 | 2021-08-13 | 西安交通大学 | Capacitor running state online monitoring method based on PCB Rogowski coil |
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Granted publication date: 20171103 Termination date: 20210217 |