CN106443120A - Differential direct current transformer control method and direct current transformer - Google Patents
Differential direct current transformer control method and direct current transformer Download PDFInfo
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- CN106443120A CN106443120A CN201610882957.2A CN201610882957A CN106443120A CN 106443120 A CN106443120 A CN 106443120A CN 201610882957 A CN201610882957 A CN 201610882957A CN 106443120 A CN106443120 A CN 106443120A
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- current transformer
- square wave
- differential type
- current
- control method
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
- G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
- G01R15/18—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using inductive devices, e.g. transformers
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
Abstract
An embodiment of the invention discloses a differential direct current transformer control method and a differential direct current transformer. The differential direct current transformer is configured with a four-channel analog switch. The method comprises the following steps of outputting a square wave and carrying out level conversion; using the square wave after the level conversion to drive the four-channel analog switch; acquiring a coupling waveform of a detection coil where an excitation current is input; and according to a preset testing index, testing a direct current lead to be tested and acquiring a testing result. By using the differential direct current transformer control method and the differential direct current transformer in the embodiment of the invention, compared to a traditional magnetic modulation transformer, on an aspect of waveform transformation, the waveform transformation adopted by the traditional magnetic modulation transformer is in a single increase or single decrease mode, but the waveform transformation of the differential magnetic induction transformer is increased and is also decreased so that measure response and measure precision during a low current are well increased.
Description
Technical field
The present invention relates to predicting wind speed of wind farm technical field, more particularly, it relates to a kind of theoretical based on combined prediction
The DC current transformer control method of differential type and the DC current transformer of differential type.
Background technology
The safe and reliable operation of power system is significant.Wherein, the accurate measurement of leakage current is important step.Pass
The leakage current transformer of system adopts unidirectional measurement for winding waveform, because this measuring method of the interference of environment and equipment exists
Larger error.
Content of the invention
In view of this, the present invention provides a kind of DC current transformer control method of differential type and the direct current of differential type
Current transformer, leaks electrometric accuracy to improve.
The present invention discloses：
A kind of DC current transformer control method of differential type, for the DC current transformer of differential type, this difference
The DC current transformer of formula is configured with four-way analog switch, and the method includes：
Output square wave go forward side by side line level conversion；
Drive described four-way analog switch using the square wave after level conversion；
Obtain the coupling waveform of the detection coil being passed through exciting current；
According to default testing index, DC wire to be measured is measured, obtains measurement result.
Preferably, described four-way analog switch is driven to include using the square wave after level conversion：
Using the two-way square wave after level conversion, control the first tandem tap group and the second tandem tap group respectively so that
Identical in the size of current of adjacent moment flowing through coil, in opposite direction.
Preferably, the coupling waveform obtaining the detection coil being passed through exciting current includes：
Described exciting current is controlled to change direction according to predetermined period, if do not had in the DC wire to be measured through coil
When having DC current to pass through, so that the coupling coil waveform being not changed in be obtained on adjacent pulse.
Preferably, the coupling waveform of coil is carried out level conversion, and returns processor entering row operation.
Preferably, the low level in the square wave of return is counted and stored, obtained the first index；
According to default testing index, DC wire to be measured is measured, obtains measurement result and include：
By count results be higher than the first index be designated as the second index, by count results be less than the first index be designated as the 3rd
Index；
Described first index, the second index and the 3rd finger target value are carried out the calculating of current value to be measured, and by result with
Form output effectively.
Preferably, described two-way square wave is to export the square wave that the cycle is 20ms and its anti-phase side respectively by two I/O ports
Ripple.
Preferably, described exciting current is spaced the periodic transformation direction of 20ms.
Invention further discloses：
A kind of DC current transformer of differential type, is configured with four-way analog switch, and includes：
Processor, for controlling：
Output square wave go forward side by side line level conversion；
Drive described four-way analog switch using the square wave after level conversion；
Obtain the coupling waveform of the detection coil being passed through exciting current；
According to default testing index, DC wire to be measured is measured, obtains measurement result.
Collecting unit, for gathering waveform, and measurement result is inputted to described processor.
Preferably, described four-way analog switch is CD4066 model, and it includes：First tandem tap group and the second series connection
Switches set.
It can be seen from above-mentioned technical scheme that, a kind of DC current transformer controlling party of differential type of the embodiment of the present invention
Method and the DC current transformer of differential type, modulate transformer compared to traditional magnetic, become in waveform and change, and traditional magnetic is modulated
The waveform conversion that transformer is used is single increase or single minimizing, the waveform conversion of differential type magnetic induction transformer
Existing increase is also reduced, and preferably improves measurement response and certainty of measurement during small current.
Brief description
In order to be illustrated more clearly that the embodiment of the present invention or technical scheme of the prior art, below will be to embodiment or existing
Have technology description in required use accompanying drawing be briefly described it should be apparent that, drawings in the following description be only this
Some embodiments of invention, for those of ordinary skill in the art, on the premise of not paying creative work, acceptable
Other accompanying drawings are obtained according to these accompanying drawings.
Fig. 1 is a kind of method flow diagram of prior art disclosed in the embodiment of the present invention；
Fig. 2 is a kind of DC current transformer control method flow chart of differential type disclosed in the embodiment of the present invention；
Fig. 3 is a kind of DC current transformer part circuit structure figure of differential type disclosed in the embodiment of the present invention；
Fig. 4 is a kind of DC current transformer control method flow chart of differential type disclosed in the embodiment of the present invention.
Specific embodiment
Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is carried out clear, complete
Site preparation description is it is clear that described embodiment is only a part of embodiment of the present invention, rather than whole embodiments.It is based on
Embodiment in the present invention, it is every other that those of ordinary skill in the art are obtained under the premise of not making creative work
Embodiment, broadly falls into the scope of protection of the invention.
The embodiment of the invention discloses a kind of DC current transformer control method of differential type and the direct current of differential type
Current transformer, leaks electrometric accuracy to improve.
At present, magnetic induction transformer is the common equipment of measurement leaky, and its principle is as follows：
In the ideal situation, there is the iron core of a geometry annular closure, here taking rectangle as a example.Left side at him
It is wound around N 1 circle coil as input, be wound around N2 circle coil as output end in right edge, be wound around the number of turn on its base simultaneously
Coil for 1, its effect is to be passed through is DC current to be detected.The collection of such a basic magnetic induction transformer
Part just completes, as shown in Figure 1.
When left side coil two ends input the electromotive force that size is E1, by Faraday's electromagnetic induction law
φ=BS
(B)
, the magnetic induction intensity of core interior creates change due to the voltage of excitation side input, in ideal conditions
Under do not consider at iron core turning leakage field phenomenon.So now by biot savart's law
The magnetic flux obtaining core interior makes induction end induce electric current, so that right-hand member N2 circle coil both sides create
Voltage difference.After DC current wire to be detected is passed through DC quantity so that the overall rising of the magnetic flux of core interior or
Decline, compared with not originally being passed through the situation of DC quantity, time difference Δ t created on waveform, by detect Δ t size and
Direction is it is known that be passed through the size and Orientation of electric current.
As can be seen here, the waveform conversion that traditional magnetic modulation transformer is used is single increase or single subtracting
Few, measure on this basis and pass judgment on certainty of measurement.But it is more serious that this method is affected ratio by external environments such as temperature, when outer
When boundary's field action, transformer is easy to produce the change of pulse length, leads to measurement result inaccurate.
For solving above technical problem, Fig. 2 shows a kind of DC current transformer control method of differential type, including：
For the DC current transformer of differential type, the DC current transformer of this differential type is configured with four-way simulation and opens
Close, the method includes：
S11：Output square wave go forward side by side line level conversion；
Be designed according to actual processor model, need to use two I/O ports export respectively the cycle be 20ms square wave with
And its anti-phase square wave., the two-way square wave that FPGA is exported is the square wave of 3.3V, does not limit to taking FPGA as a example.
Because the driving square wave required for subsequent conditioning circuit is 5V square wave.And the 3.3V square wave that FPGA directly exports is unsatisfactory for wanting
Ask, so needing waveform to change.The square wave that processor is exported carries out level conversion.Square wave phase after conversion is constant, width
Degree is become for 5V by 3.3V.Meet the needs of subsequent conditioning circuit.
S12：Drive described four-way analog switch using the square wave after level conversion；
As shown in figure 3, the CD4066 being used is the analog switch of a four-way, by process through level conversion
Square wave is driving it.Two-way square wave, controlling switch AD and switch BC respectively.So that the electric current in adjacent moment flowing through coil is big
Little identical, in opposite direction.When driving ripple 1 to open CD4066, switch A is turned on switch D, other cut-offs.Electric current flows clockwise
Cross coil.When driving ripple 2 to open CD4066, switch B is turned on switch C, other switch cut-offs.The electric current of flowing through coil and drive
The situation of dynamic ripple 1 is contrary.
S13：Obtain the coupling waveform of the detection coil being passed through exciting current；
It has been passed through exciting current in detection coil, preferably, described exciting current will convert once every 20ms
Direction, if passing through without DC current, can obtain one in adjacent pulse in the DC wire to be measured through coil
On the coupling coil waveform that is not changed in.
S14：According to default testing index, DC wire to be measured is measured, obtains measurement result.
After the coupling waveform obtaining coil, due to now there is no electric current to be measured.So between adjacent pulse not
Change.The coupling waveform of coil is passed through level conversion, when coupling waveform by integrated transporting discharging, because amplifier does not introduce instead
Feedback, so it is operated in saturation region.
It is output as power supply, i.e. the square wave of ± 12V and anti-phase with original waveform, become after passing through triode afterwards
3.3V square wave and again carried out anti-phase.
Waveform now and former coupled wave are just as phase, and are to return the 3.3V square wave that processor enters row operation.From
And the waveform in this embodiment converts existing increase and is also reduced, preferably improve measurement response during small current.
As shown in Figure 4：
S41：Low level in the square wave returning is counted and is stored；
Due to now not detecting that electric current is passed through, so the result counting is result during 0mA, it is designated as Level, that is, the
One index.
As DC wire to be measured is passed through electric current by figure, it is exemplified as 100mA here.
S42：Low level is counted and result is stored, by count results be higher than Level be designated as Top, that is, the
Two indexs；
S43：By count results be less than Level be designated as Bottom, i.e. the 3rd index.
According to the Level having obtained, the value of Top, Bottom must calculate carrying out current value to be measured, and by result to have
The form output of effect ground.Taking 100mA as a example.Send the commands to read and write response variable by UART, and external two I/O ports connect LED mould
Whether block convenient observation calibration is successful.Its corresponding authority is as shown in table 1.
Table 1 calibrating mode and corresponding authority
The embodiment of the invention also discloses a kind of DC current transformer of differential type：It is configured with four-way analog switch,
And include：
Processor, for controlling：
Output square wave go forward side by side line level conversion；
Drive described four-way analog switch using the square wave after level conversion；
Obtain the coupling waveform of the detection coil being passed through exciting current；
According to default testing index, DC wire to be measured is measured, obtains measurement result；
And, collecting unit, for gathering waveform, and measurement result is inputted to described processor.
As shown in Figure 3：Described four-way analog switch is CD4066 model, and it includes：First tandem tap group and second
Tandem tap group.
For the embodiment of the DC current transformer of differential type, implement because it essentially corresponds to control method
Example, so describing fairly simple, in place of correlation, the part referring to embodiment of the method illustrates.Device described above is real
Applying example is only schematically, and the wherein said unit that illustrates as separating component can be or may not be and physically divide
Open, as the part that unit shows can be or may not be physical location, you can with positioned at a place, or
Can be distributed on multiple NEs.Some or all of module therein can be selected according to the actual needs to realize this
The purpose of embodiment scheme.Those of ordinary skill in the art are not in the case of paying creative work, you can simultaneously real to understand
Apply.
It should be noted that in this manual, such as first and second or the like relational terms are used merely to one
Individual entity or operation are made a distinction with another entity or operation, and not necessarily require or imply these entities or operate it
Between there is any this actual relation or order.And, term " inclusion ", "comprising" or its any other variant are intended to
Cover comprising of nonexcludability, so that including a series of process of key elements, method, article or equipment not only include those
Key element, but also include other key elements being not expressly set out, or also include for this process, method, article or set
Standby intrinsic key element.In the absence of more restrictions, the key element that limited by sentence "including a ..." it is not excluded that
Also there is other identical element in process, method, article or the equipment including described key element.
In sum：
A kind of DC current transformer control method of differential type of the embodiment of the present invention and the DC current mutual inductance of differential type
Device, overcomes Classical forecast strategy because, under changeable short-term wind speed scene, all exist using fixing Forecasting Methodology is accurate
Property low limitation, by carrying out to the chaos time sequence of current wind speed decomposing, component parameters compensate with new, scheme collection and genus
Property collection be directed to the prediction of each component, and after calculating optimum multiple attribute decision making (MADM) predicted value, each component is carried out reconfiguring and
Reciprocal transformation, reaches direct forecast model and carries out error revising and compensating to predicting the outcome, in conjunction with multiple intelligent forecast models, for carrying
The precision of prediction of high short-term wind speed provides reliable method it is achieved that tackling wind energy turbine set short-term wind speed situation of change complicated and changeable,
Improve the technical purpose of forecasting accuracy.
In this specification, each embodiment is described by the way of going forward one by one, and what each embodiment stressed is and other
The difference of embodiment, between each embodiment identical similar portion mutually referring to.For system disclosed in embodiment
For, because it corresponds to the method disclosed in Example, so description is fairly simple, say referring to method part in place of correlation
Bright.
It will be understood by those skilled in the art that can be represented using any one in many different techniques and technology
Information, message and signal.For example, the message mentioned in described above, information may be expressed as voltage, electric current, electromagnetic wave,
Magnetic field or magnetic particle, light field or more are combined.
The step of the method in conjunction with the embodiments described herein description or algorithm can directly be held with hardware, processor
The software module of row, or the combination of the two is implementing.Software module can be placed in random access memory (RAM), internal memory, read-only deposit
Reservoir (ROM), electrically programmable ROM, electrically erasable ROM, register, hard disk, moveable magnetic disc, CD-ROM or technology
In known any other form of storage medium in field.
Described above to the disclosed embodiments, makes professional and technical personnel in the field be capable of or uses the present invention.
Multiple modifications to these embodiments will be apparent from for those skilled in the art, as defined herein
General Principle can be realized in the case of the spirit or scope without departing from the embodiment of the present invention in other embodiments.Therefore,
The embodiment of the present invention is not intended to be limited to the embodiments shown herein, and be to fit to principles disclosed herein and
The consistent scope the widest of features of novelty.
Claims (9)
1. a kind of DC current transformer control method of differential type is it is characterised in that be used for the DC current mutual inductance of differential type
Device, the DC current transformer of this differential type is configured with four-way analog switch, and the method includes：
Output square wave go forward side by side line level conversion；
Drive described four-way analog switch using the square wave after level conversion；
Obtain the coupling waveform of the detection coil being passed through exciting current；
According to default testing index, DC wire to be measured is measured, obtains measurement result.
2. after the DC current transformer control method of differential type as claimed in claim 1 is it is characterised in that utilize level conversion
Square wave drive described four-way analog switch include：
Using the two-way square wave after level conversion, control the first tandem tap group and the second tandem tap group respectively so that in phase
The size of current of adjacent moment flowing through coil is identical, in opposite direction.
3. the DC current transformer control method of differential type as claimed in claim 1 is passed through excitation electricity it is characterised in that obtaining
The coupling waveform of the detection coil of stream includes：
Described exciting current is controlled to change direction according to predetermined period, without straight in the DC wire to be measured through coil
When stream electric current passes through, so that the coupling coil waveform being not changed in be obtained on adjacent pulse.
4. as described in claim 1-3 the DC current transformer control method of differential type it is characterised in that also including：
The coupling waveform of coil is carried out level conversion, and returns processor entering row operation.
5. the DC current transformer control method of differential type as claimed in claim 4 is it is characterised in that also include：
Low level in the square wave of return is counted and is stored, obtained the first index；
According to default testing index, DC wire to be measured is measured, obtains measurement result and include：
By count results be higher than the first index be designated as the second index, by count results be less than the first index be designated as the 3rd finger
Mark；Described first index, the second index and the 3rd finger target value are carried out the calculating of current value to be measured, and by result with effectively
Form exports.
6. differential type as claimed in claim 2 DC current transformer control method it is characterised in that
Described two-way square wave is to export the square wave that the cycle is 20ms and its anti-phase square wave respectively by two I/O ports.
7. the DC current transformer control method of differential type as claimed in claim 2 is it is characterised in that between described exciting current
Periodic transformation direction every 20ms.
8. a kind of DC current transformer of differential type is it is characterised in that be configured with four-way analog switch, and includes：
Processor, for controlling：
Output square wave go forward side by side line level conversion；
Drive described four-way analog switch using the square wave after level conversion；
Obtain the coupling waveform of the detection coil being passed through exciting current；
According to default testing index, DC wire to be measured is measured, obtains measurement result；
Collecting unit, for gathering waveform, and measurement result is inputted to described processor.
9. the DC current transformer of differential type as claimed in claim 8 is it is characterised in that described four-way analog switch is
CD4066 model, it includes：First tandem tap group and the second tandem tap group.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201610882957.2A CN106443120A (en) | 2016-10-10 | 2016-10-10 | Differential direct current transformer control method and direct current transformer |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610882957.2A CN106443120A (en) | 2016-10-10 | 2016-10-10 | Differential direct current transformer control method and direct current transformer |
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|---|---|
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Family
ID=58172142
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| CN204740317U (en) * | 2015-06-10 | 2015-11-04 | 宁波星成电子有限公司 | Current sensor is leaked to difference |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4517513A (en) * | 1982-07-16 | 1985-05-14 | At&T Bell Laboratories | Magnetic differential current sensor |
| JPS60196678A (en) * | 1984-03-21 | 1985-10-05 | Mishima Kosan Co Ltd | Differential self-exciting bridge type current sensor |
| JPS633616A (en) * | 1986-06-05 | 1988-01-08 | シ−メンス、アクチエンゲゼルシヤフト | Failure current detector |
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Application publication date: 20170222 |