CN208705467U - A kind of DC electronic transformer detection converter - Google Patents
A kind of DC electronic transformer detection converter Download PDFInfo
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- CN208705467U CN208705467U CN201821461881.7U CN201821461881U CN208705467U CN 208705467 U CN208705467 U CN 208705467U CN 201821461881 U CN201821461881 U CN 201821461881U CN 208705467 U CN208705467 U CN 208705467U
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Abstract
A kind of DC electronic transformer provided by the utility model detects converter, converter is made to be adapted to three kinds of inputs by multiple selector, small voltage signal is converted to by the precision resistance of milliohm grade as high current input signal is inputted by the first input channel port, low current input signal is inputted by the second input channel port and is converted to small voltage signal by conventional tight resistance, small voltage signal is inputted by third input channel port, realize high current input signal, low current input signal and small voltage signal can be converted by the converter of the utility model, it can complete the sampling to different type analog input signal, be converted to the digital signal of corresponding encoded, it is sent to the tester body apparatus of rear end, realize the closed loop verification of direct current instrument transformer, it solves current direct current instrument transformer closed loop test to need repeatedly The technical issues of replacing converter.
Description
Technical field
The utility model relates to direct current instrument transformer technical field more particularly to a kind of detection conversions of DC electronic transformer
Device.
Background technique
Direct current instrument transformer provides accurately and reliably sampled measurements information, operational reliability and measurement accuracy direct relation
It is the important link in DC transmission system to the operation stability and reliability of direct current control and protection system.To guarantee direct current mutual inductance
The reliability service of device, test and periodical regular inspection before needing to put into operation to direct current instrument transformer.At the scene in operational process, due to
Lack relevant criterion regulation and unified perfect on-site calibrating method and test device, direct current instrument transformer on-the-spot test generally can only
Carry out direct current open loop test, this test method is not only high to the stability requirement of DC source, and be difficult to realize test product with
The synchro measure of DC source, test result are not accurate enough.Currently, being that direct current is mutual based on the closed loop method of calibration that homologous back production compares
The research new direction of sensor measuring technology.
The onthe technology of site test of DC electronic transformer includes two class of open-loop test and closed loop test at present.Open-loop test
Mode: exporting direct current signal using High-accuracy direct current source, after the direct current instrument transformer progress of disease, accesses test instrumentation, passes through artificial side
Formula compares the difference of direct current instrument transformer output signal and raw DC source output signal, carries out school to direct current instrument transformer Transfer characteristic
It tests.Closed loop test mode: DC source outputting standard direct current signal accesses tester after the direct current instrument transformer progress of disease；Meanwhile by
The analog signals of input converter synchronous acquisition standard dc source output, are also transmitted after being converted to digital signal through optical-fibre channel
To tester.The closed loop back production Inspection of direct current instrument transformer is automatically performed by tester.
Existing direct current instrument transformer open-loop test, the performance indicator and stability of DC source output signal cannot be fully met
It is required that, it is difficult to the load characteristic variation of various principle direct current instrument transformers is adapted to, test result is not accurate enough.
Current direct current instrument transformer closed loop test mode, the not yet interface and function of unified converter.Due to test item
Different (steady state test and transient tests), and (small voltage output, low current export, are big standard dc source output interface disunity
Electric current output etc.), the direct current instrument transformer detection converter of scene actual use is many kinds of, corresponding sampling rate, sampling
Range, low-pass filtering circuit are all had any different, and may need to replace converter repeatedly in test process, and test operation is cumbersome, are reduced
The reliability of test equipment and test result.
Direct current instrument transformer closed loop check system is made of standard dc source, converter and tester ontology three parts.Conversion
Device acquires the analog signals of standard dc source output, is converted to and is transmitted to tester ontology through optical-fibre channel after digital signal,
Realize the closed loop back production Inspection of direct current instrument transformer.Standard source analog signal is converted to digital signal by converter, will be primary
System is isolated with check system, improves the safety of on-the-spot test, the sampling nature and operation stability of converter are direct currents
Important link in transducer check system.In practical application, since test content is different (steady state test and transient test), and
Standard dc source interface disunity (small voltage output, low current output, High-current output etc.), the direct current instrument transformer that scene uses
Detection converter is many kinds of, and corresponding sampling rate, sample range, low-pass filtering circuit are all had any different, on-the-spot test
It needs to replace converter repeatedly in journey, test operation is cumbersome.It is existing to direct current instrument transformer to study adaptively sampled detection converter
The development of field detecting work is of great significance.
Standard source analog signal is converted to digital signal by converter, and primary system is isolated with check system, is improved
The safety of on-the-spot test.According to live actual test project and the standard dc source model of use, in use may
It needs to replace repeatedly.For exporting the steady-state DC source of small voltage signal, the converter using small voltage input interface is needed；It is right
In the steady-state DC source of output low current signal, the converter using low current input interface is needed；For output high current letter
Number transient state step DC source, need using transient state converter.
Therefore, it is necessary to design a kind of converter that can adapt to various situations, solves current direct current instrument transformer closed loop and survey
Examination needs the technical issues of replacing converter repeatedly.
Utility model content
The utility model discloses a kind of DC electronic transformers to detect converter, can complete to simulate different type
The sampling for measuring input signal, is converted to the digital signal of corresponding encoded, is sent to the tester body apparatus of rear end, realizes direct current
The closed loop of mutual inductor verifies, and solves current direct current instrument transformer closed loop test and needs the technical issues of replacing converter repeatedly.
The utility model provides a kind of DC electronic transformer detection converter, comprising: milliohm grade precision resistance, often
Advise precision resistance, multiple selector, filter module, proportion adjustment module, AD conversion module and optical fiber receiver-transmitter module；
First input channel port of converter is connected to the input terminal of multiple selector by milliohm grade precision resistance, turns
Second input channel port of parallel operation is connected to the input terminal of multiple selector by conventional fine resistance, and the third of converter is defeated
Enter the input terminal of access port connection multiple selector；
Output end, filter module, proportion adjustment module, AD conversion module and the optical fiber receiver-transmitter module of multiple selector are successively
Connection.
Preferably, multiple selector has 3 tunnel input channels and 1 tunnel output channel, for selecting 1 from 3 tunnel input channels
The small voltage signal of road input channel is exported to output channel.
Preferably, filter module is specially variable filter module；
Variable filter module includes three filter circuits for being in series with switch, and three are in series between the filter circuit of switch
It is in parallel.
Preferably, filter circuit is specially second order active low-pass filter circuit.
Preferably, second order active low-pass filter circuit include: first resistor, second resistance, first capacitor, the second capacitor and
First amplifier；
First end and second electricity of the input terminal of second order active low-pass filter circuit by first resistor connection first capacitor
The first end of resistance；
The second end of second resistance connects the first end of the second capacitor and the positive input terminal of the first amplifier；
The second end of second capacitor is grounded；
The output end of the second end of first capacitor, the negative input end of the first amplifier and the first amplifier is connected and as two
The output end of rank active low-pass filter circuit.
Preferably, proportion adjustment module is specially variable proportion adjustment module；
Variable proportion adjustment module specifically includes three in-phase proportion computing circuits for being in series with switch, and three are in series with out
It is in parallel between the in-phase proportion computing circuit of pass.
Preferably, in-phase proportion computing circuit includes: the 7th resistance, the 8th resistance, the 9th resistance and the 4th amplifier；
The input terminal of in-phase proportion computing circuit connects the positive input terminal of the 4th amplifier by the 9th resistance；
The first end of 8th resistance is grounded, and the second end of the 8th resistance connects the negative input end and the 7th electricity of the 4th amplifier
The first end of resistance；
The second end of 7th resistance is connected with the output end of the 4th amplifier and the output as in-phase proportion computing circuit
End.
Preferably, AD conversion module is specially 18 gradual approaching A/D converters.
Preferably, it is preferable that optical fiber receiver-transmitter module is specially serial optical fiber transceiving device.
It preferably, further include rechargable power supplies module；
Rechargable power supplies module is separately connected multiple selector, filter module, proportion adjustment module, AD conversion module and light
Fine transceiver module.
As can be seen from the above technical solutions, the utility model embodiment has the advantage that
The utility model provides a kind of DC electronic transformer detection converter, comprising: milliohm grade precision resistance, often
Advise precision resistance, multiple selector, filter module, proportion adjustment module, AD conversion module and optical fiber receiver-transmitter module；Converter
First input channel port is connected to the input terminal of multiple selector by milliohm grade precision resistance, and the second input of converter is logical
Road port is connected to the input terminal of multiple selector by conventional fine resistance, and the third input channel port connection of converter is more
The input terminal of road selector；Output end, filter module, proportion adjustment module, AD conversion module and the optical fiber of multiple selector are received
Hair module is sequentially connected.The utility model makes converter be adapted to three kinds of inputs by multiple selector, as high current is defeated
Enter signal and small voltage signal, low current input letter are converted to by the precision resistance of milliohm grade by the input of the first input channel port
It number is inputted by the second input channel port and small voltage signal is converted to by conventional tight resistance, small voltage signal is inputted by third
Access port input, realizing high current input signal, low current input signal and small voltage signal can be practical by this
Novel converter is converted, and can complete to be converted to corresponding encoded to the sampling of different type analog input signal
Digital signal is sent to the tester body apparatus of rear end, realizes the closed loop verification of direct current instrument transformer, it is mutual to solve current direct current
Sensor closed loop test needs the technical issues of replacing converter repeatedly.
Detailed description of the invention
In order to illustrate the embodiment of the utility model or the technical proposal in the existing technology more clearly, below will be to embodiment
Or attached drawing needed to be used in the description of the prior art is briefly described, it should be apparent that, the accompanying drawings in the following description is only
It is some embodiments of the utility model, for those of ordinary skill in the art, before not making the creative labor property
It puts, can also be obtained according to these attached drawings other attached drawings.
Fig. 1 is the circuit of one embodiment that a kind of DC electronic transformer provided by the utility model detects converter
Schematic diagram；
Fig. 2 is that a kind of DC electronic transformer provided by the utility model is detected and filtered in one embodiment of converter
The circuit diagram of module；
Fig. 3 is that a kind of DC electronic transformer provided by the utility model detects ratio in one embodiment of converter
The circuit diagram of adjustment module.
Specific embodiment
The utility model discloses a kind of DC electronic transformers to detect converter, can complete to simulate different type
The sampling for measuring input signal, is converted to the digital signal of corresponding encoded, is sent to the tester body apparatus of rear end, realizes direct current
The closed loop of mutual inductor verifies, and solves current direct current instrument transformer closed loop test and needs the technical issues of replacing converter repeatedly.
Referring to Fig. 1, a kind of one embodiment of DC electronic transformer detection converter provided by the utility model,
It include: milliohm grade precision resistance, conventional fine resistance, multiple selector, filter module, proportion adjustment module, AD conversion module
And optical fiber receiver-transmitter module；
First input channel port of converter is connected to the input terminal of multiple selector by milliohm grade precision resistance, turns
Second input channel port of parallel operation is connected to the input terminal of multiple selector by conventional fine resistance, and the third of converter is defeated
Enter the input terminal of access port connection multiple selector；
Output end, filter module, proportion adjustment module, AD conversion module and the optical fiber receiver-transmitter module of multiple selector are successively
Connection.
The utility model by multiple selector make converter be adapted to three kinds input, as high current input signal by
The input of first input channel port is converted to small voltage signal subsequently into multiple selector by the precision resistance of milliohm grade, small
Current input signal is inputted by the second input channel port and is converted to small voltage signal subsequently into more by conventional tight resistance
Road selector, small voltage signal are inputted by third input channel port subsequently into multiple selector, realize high current input
Signal, low current input signal and small voltage signal can be converted by the converter of the utility model, can be completed
Sampling to different type analog input signal is converted to the digital signal of corresponding encoded, is sent to the tester sheet of rear end
Body device realizes the closed loop verification of direct current instrument transformer, solves current direct current instrument transformer closed loop test and need to replace conversion repeatedly
The technical issues of device.
Further, multiple selector has 3 tunnel input channels and 1 tunnel output channel, for selecting from 3 tunnel input channels
The small voltage signal of 1 tunnel input channel is exported to output channel.
Select 1 tunnel input channel that can realize by switching circuit from 3 tunnel input channels.
Further, filter module is specially variable filter module；
Variable filter module includes three filter circuits for being in series with switch, and three are in series between the filter circuit of switch
It is in parallel.
Further, filter circuit is specially second order active low-pass filter circuit.
Further, referring to Fig. 2, Fig. 2 is the circuit diagram of filter module；R1 to R6 is the first to the 6th resistance in Fig. 2,
C1 to C6 is the first to the 6th capacitor, and OP1 to OP3 is first to third amplifier；
Referring to Fig. 2, the second order active low-pass filter circuit in filter module includes: first resistor, second resistance, first
Capacitor, the second capacitor and the first amplifier；
First end and second electricity of the input terminal of second order active low-pass filter circuit by first resistor connection first capacitor
The first end of resistance；
The second end of second resistance connects the first end of the second capacitor and the positive input terminal of the first amplifier；
The second end of second capacitor is grounded；
The output end of the second end of first capacitor, the negative input end of the first amplifier and the first amplifier is connected and as two
The output end of rank active low-pass filter circuit.
Other two second order active low-pass filter circuit is as above-mentioned second order active low-pass filter circuit principle, herein
It repeats no more.
Filter circuit uses second order active low-pass filter circuit, Parameter adjustable, by change resistance R1, R2 and capacitor C1,
The size of C2 can adjust the cutoff frequency of filter circuit output signal, obtains and filters out at ability and signal to high-frequency interferencing signal
Manage the equalization point of delay time between the two.By switching selection switch, switch the signal filtering channel of different parameters, realizes filtering
The characteristic variable in circuit, to be suitble to a variety of different signal filtering parameter matching schemes.
Further, proportion adjustment module is specially variable proportion adjustment module；
Variable proportion adjustment module specifically includes three in-phase proportion computing circuits for being in series with switch, and three are in series with out
It is in parallel between the in-phase proportion computing circuit of pass.
Further, referring to Fig. 3, Fig. 3 be proportion adjustment module circuit diagram, wherein R7 to R15 be the 7th resistance extremely
15th resistance, OP4 to OP6 are the 4th amplifier to the 6th amplifier.
Referring to Fig. 3, in-phase proportion computing circuit includes: the 7th resistance, the 8th resistance, the 9th resistance and the 4th amplification
Device；
The input terminal of in-phase proportion computing circuit connects the positive input terminal of the 4th amplifier by the 9th resistance；
The first end of 8th resistance is grounded, and the second end of the 8th resistance connects the negative input end and the 7th electricity of the 4th amplifier
The first end of resistance；
The second end of 7th resistance is connected with the output end of the 4th amplifier and the output as in-phase proportion computing circuit
End.
Other two in-phase proportion computing circuit is no longer superfluous herein as above-mentioned in-phase proportion computing circuit principle
It states.
Proportion adjustment circuit uses in-phase proportion computing circuit, by the resistance value for adjusting resistance R7, R8, thus it is possible to vary output
The proportionate relationship of signal and input signal is adjusted to small voltage signal proportion is originally inputted, to adapt to external variety classes
Analog quantity sampled signal.Inside modules preset the resistive element of multiple groups different parameters, realize the tune of various different proportion relationships
Economize on electricity road, the signal proportion adjustment parameter that control switching switch selection actually uses, cooperates different types of analog input letter
Number, be converted to the A/D module conversion small voltage of standard.
Further, AD conversion module is specially 18 gradual approaching A/D converters.Using 18 gradually force
Plesiotype analog-digital converter AD7982, sample rate maximum 1000kSPS are, it can be achieved that high-precision, the analog-digital conversion function of high sampling rate.
AD7982 is powered using 2.5V single supply, when a built-in low-power consumption, high speed, 18 no missing code sampling ADCs, an internal conversion
Clock and a multi-functional serial interface port.In conversion signal rising edge, the device is to the voltage difference between Differential Input pin
It is sampled.Reference voltage is provided by outside, and can be set to supply voltage.The power consumption and throughput rate of the device are in line
Property variation relation.It supports SPI communication mode and daisy chain to link mode, and an optional busy instruction is provided.
Further, further, optical fiber receiver-transmitter module is specially serial optical fiber transceiving device.Optical fiber and digital transceiver module
Using the serial optical fiber transceiving device of HFBR 1414 and AFBR 2418TZ of Avago company, has the optical signal transceiver energy of high speed
Power can meet the serial data transmitting-receiving demand under most baud rates.
1414 fiber optic transmitter part of HFBR uses the ST interface of Tube packaged type, and operating temperature -40 is maximum to 85 degree
Rise time: 6.5ns, maximum fall time: 6.5ns, pulse width distortion: 7.56ns.
AFBR 2418TZ fiber optic receiver part uses ST interface, and operating temperature -40 receives data wavelength to 85 degree
865nm receives data rate maximum 50MBd, has good data compatibility.
It further, further include rechargable power supplies module；
Rechargable power supplies module is separately connected multiple selector, filter module, proportion adjustment module, AD conversion module and light
Fine transceiver module.
For the electrical isolation for realizing primary measured equipment and second test system, the safety of test process is ensured, convert
Device is preferably placed in direct current instrument transformer to be measured and standard source near zone on the spot, and therefore, converter should have that battery is independently-powered to be made
Ability.
In the rechargeable battery of converter inside placement large capacity, battery is full of using preceding, converter in test process
It powers without additional power supply.Cell output voltage is converted to various specifications by the power supply chip inside device, meets internal different
The work requirements in chip circuit.
Power module is made of built-in rechargeable battery and linear voltage regulator.
Charged battery voltage 9V, battery capacity 8000mAh, can provide after fully charged converter continue working 12 hours with
On.
Rear end use AMS1117 linear voltage regulator, by rechargeable battery export 9V voltage be converted to 1.2V, 2.5V, 3.3V,
Several groups of 5V, stable working power is provided for the various chips of converter inside.
A kind of DC electronic transformer detection converter provided by the utility model is described in detail above,
For those of ordinary skill in the art, based on the idea of the embodiment of the present invention, in specific embodiment and application range
Upper there will be changes, in conclusion the content of the present specification should not be construed as a limitation of the present invention.
Claims (10)
1. a kind of DC electronic transformer detects converter characterized by comprising milliohm grade precision resistance, conventional fine
Resistance, multiple selector, filter module, proportion adjustment module, AD conversion module and optical fiber receiver-transmitter module；
First input channel port of the converter is connected to the multiple selector by the milliohm grade precision resistance
Second input channel port of input terminal, the converter is connected to the multiple selector by the conventional fine resistance
Input terminal, the third input channel port of the converter connect the input terminal of the multiple selector；
The output end of the multiple selector, the filter module, the proportion adjustment module, the AD conversion module and described
Optical fiber receiver-transmitter module is sequentially connected.
2. a kind of DC electronic transformer according to claim 1 detects converter, which is characterized in that the multichannel choosing
Selecting device has 3 tunnel input channels and 1 tunnel output channel, for selecting the small voltage signal of 1 tunnel input channel from 3 tunnel input channels
It exports to output channel.
3. a kind of DC electronic transformer according to claim 1 detects converter, which is characterized in that the filtering mould
Block is specially variable filter module；
The variable filter module includes three filter circuits for being in series with switch, and described three are in series with the filter circuit of switch
Between it is in parallel.
4. a kind of DC electronic transformer according to claim 3 detects converter, which is characterized in that the filtered electrical
Road is specially second order active low-pass filter circuit.
5. a kind of DC electronic transformer according to claim 4 detects converter, which is characterized in that the second order has
Source low-pass filter circuit includes: first resistor, second resistance, first capacitor, the second capacitor and the first amplifier；
The input terminal of the second order active low-pass filter circuit connects the first end of the first capacitor by the first resistor
With the first end of the second resistance；
The second end of the second resistance connects the first end of second capacitor and the positive input terminal of first amplifier；
The second end of second capacitor is grounded；
The second end of the first capacitor, first amplifier negative input end be connected with the output end of first amplifier
And the output end as the second order active low-pass filter circuit.
6. a kind of DC electronic transformer according to claim 1 detects converter, which is characterized in that the ratio tune
Saving module is specially variable proportion adjustment module；
The variable proportion adjustment module specifically includes three in-phase proportion computing circuits for being in series with switch, three series connection
Have in parallel between the in-phase proportion computing circuit of switch.
7. a kind of DC electronic transformer according to claim 6 detects converter, which is characterized in that described compared with
Example computing circuit includes: the 7th resistance, the 8th resistance, the 9th resistance and the 4th amplifier；
The input terminal of the in-phase proportion computing circuit connects the positive input terminal of the 4th amplifier by the 9th resistance；
The first end of 8th resistance is grounded, and the second end of the 8th resistance connects the negative input end of the 4th amplifier
With the first end of the 7th resistance；
The second end of 7th resistance is connected and with the output end of the 4th amplifier as in-phase proportion computing circuit
Output end.
8. a kind of DC electronic transformer according to claim 1 detects converter, which is characterized in that the AD conversion
Module is specially 18 gradual approaching A/D converters.
9. a kind of DC electronic transformer according to claim 1 detects converter, which is characterized in that the optical fiber is received
Sending out module is specially serial optical fiber transceiving device.
10. a kind of DC electronic transformer according to claim 1 detects converter, which is characterized in that further including can
Charging power modules；
The rechargable power supplies module is separately connected the multiple selector, the filter module, the proportion adjustment module, institute
State AD conversion module and the optical fiber receiver-transmitter module.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201821461881.7U CN208705467U (en) | 2018-09-06 | 2018-09-06 | A kind of DC electronic transformer detection converter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201821461881.7U CN208705467U (en) | 2018-09-06 | 2018-09-06 | A kind of DC electronic transformer detection converter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN208705467U true CN208705467U (en) | 2019-04-05 |
Family
ID=65946693
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201821461881.7U Active CN208705467U (en) | 2018-09-06 | 2018-09-06 | A kind of DC electronic transformer detection converter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN208705467U (en) |
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2018
- 2018-09-06 CN CN201821461881.7U patent/CN208705467U/en active Active
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