CN105023677B - High accuracy is adjustable combined resistance, Auto-Test System and method based on the combined resistance - Google Patents
High accuracy is adjustable combined resistance, Auto-Test System and method based on the combined resistance Download PDFInfo
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- CN105023677B CN105023677B CN201510478097.1A CN201510478097A CN105023677B CN 105023677 B CN105023677 B CN 105023677B CN 201510478097 A CN201510478097 A CN 201510478097A CN 105023677 B CN105023677 B CN 105023677B
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Abstract
High accuracy is adjustable combined resistance, Auto-Test System and method based on the combined resistance, are related to exploitation and the design field of precision resister.The present invention is in order to solve existing combined resistance and its Auto-Test System builds that complicated, measurement accuracy is low and Auto-Test System test mode of existing combined resistance is complicated and affected by environment so that the problem of relatively low measurement accuracy.In high-precision adjustable combined resistance, according to the input signal of an input terminal and No. two input terminals, the ratio of regulation port voltage and electric current carrys out simulation output resistance R.The Auto-Test System of high-precision adjustable combined resistance, the voltage and current of combined resistance is measured by two universal meters respectively, and measurement result is sent to the storage and processing that measurement result is completed in PC, PC by serial ports, realizes automatic test.The present disclosure additionally applies for the automatic test of other resistance and resistance.
Description
Technical field
The present invention relates to the exploitation of precision resister and design field.
Background technology
The effect of high-precision combined resistance is to obtain precision resister by numerical control, and it is mainly used in resistance class sensor
Test circuit or instrument automatic calibration.The Auto-Test System of high-precision combined resistance can test combined resistance automatically
Parameters, additionally it is possible to be more conveniently accomplished the self-inspection of combined resistance.
Existing high-precision combined resistance majority realizes combined resistance using operational amplifier and digital analog converter, then passes through
Programming obtains the ratio of input voltage and electric current, you can obtain programmable linear resistance.But build in this way
Combined resistance is extremely complex in build process, and when the reference voltage of digital analog converter is smaller, combined resistance precision
It is not high.Therefore there is high-precision combined resistance to be very necessary for research and development one.And the test system of existing combined resistance is more
Using high accuracy number universal meter, realized by manual methods.But manual measurement very complicated, and due to environmental factor
So that measured value deviation is larger, it can not be applied in high-acruracy survey.
The content of the invention
The present invention in order to solve existing combined resistance and its Auto-Test System to build complicated, measurement accuracy low and existing
Combined resistance Auto-Test System test mode it is complicated and affected by environment the problem of cause relatively low measurement accuracy, proposition
High-precision adjustable combined resistance, Auto-Test System and method based on the combined resistance.
The core design of the present invention is the application of integrated AD/DA boards and central processing unit, compared with conventional synthesis resistance,
High-precision integrated AD/DA boards improve the precision of combined resistance, and central processing unit is easy to extension, can be embedded in a variety of calculations
Method, such as average value filtering, PID control etc., and because integrated level is high so that its stability is good.And the letter being embedded in PC
Number processing module is used to gathering, store and handle voltage data and the current data that universal meter is gathered.Wherein, average value filtering is
The high-frequency signal of input is filtered, finally makes combined resistance value more accurate；PID control gathers actual synthesis electricity in real time
Resistance, and be compared and follow with the combined resistance value of setting, make the combined resistance value finally obtained more accurate.
The adjustable combined resistance of high accuracy, it includes an input terminal A0, No. two input terminal B0, at signal front end
Manage circuit 1, integrated AD/DA boards 2, source of stable pressure 3 and central processing unit 4；
Signal front-end processing circuit 1 includes sampling resistor Rb and operational amplifier A；Sampling resistor Rb one end concatenation operation
Amplifier A electrode input end；The negative input of operational amplifier A concatenation operation amplifier A output end and integrated simultaneously
The AD signal input parts of AD/DA boards 2；The cathode power supply output of the cathode power supply input connection source of stable pressure 3 of operational amplifier A
End；The negative power supply input of operational amplifier A connects the negative power supply output end of source of stable pressure 3；
Number input terminal A0 connection sampling resistors Rb one end；Sampling resistor Rb other end ground connection；No. two inputs
The DA signal input parts of the integrated AD/DA boards 2 of terminals B0 connections；
The AD/DA signal input output ends of central processing unit 4 connect the AD/DA signal outputs input of integrated AD/DA boards 2
End.
Based on the Auto-Test System of the adjustable combined resistance of high accuracy, the system also includes PC 5, an and of universal meter 6
No. two universal meters 7；Embedded signal processing module 5-1 in PC 5；
Two output ends of a number universal meter 6 connect sampling resistor Rb two ends respectively；The two ends difference of No. two universal meters 7
Connect an input terminal A0 and No. two input terminal B0；Connected between a number universal meter 6 and PC 5 by serial ports；Two
Number connected between universal meter 7 and PC 5 by serial ports；
Signal processing module 5-1 is used to gathering, store and handling the data that a universal meter 6 and No. two universal meters 7 are gathered.
The automatic test approach of the Auto-Test System of high-precision adjustable combined resistance, the automatic test approach includes following
Step：
Step 1: adding between an input terminal A0 and No. two input terminal B0 for the adjustable combined resistance of high accuracy
Enter test and excitation, test and excitation is voltage source or current source；
Step 2: measuring the electric current of input using a universal meter 6, the voltage of input is measured using No. two universal meters 7；
Step 3: the serial ports parameter of a universal meter 6 and No. two universal meters 7 is set, including serial port baud rate and odd even school
Position is tested, while setting the serial ports parameter of signal processing module 5-1 in PC 5, distinguishes signal processing module 5-1 serial ports parameter
It is consistent with the serial ports parameter of a universal meter 6 and No. two universal meters 7；
Step 4: setting time of measuring interval and time of measuring by the signal processing module 5-1 in PC 5, and connect
A number universal meter 6 and No. two universal meters 7 are at remote state, start test；
Step 5: the signal processing module 5-1 in PC 5 gathers the voltage that a universal meter 6 and No. two universal meters 7 are measured
Data or current data, and voltage data or current data are included on PC 5 in graphical form；Meanwhile, signal transacting mould
Block 5-1 does average value processing to voltage data or current data, obtains average voltage and current average, average voltage and electricity
Levelling average is divided by as final measurement resistance value.
The electric current of a number measurement input of universal meter 6 of use in step 2 is that input current is converted into electricity by sampling resistor
Pressure realizes measurement.
Beneficial effect：
1st, the adjustable combined resistance of high accuracy based on integrated AD/D boards, can easily obtain the resistance of adjustable combined resistance
Value, compared with conventional synthesis resistance, the adjustable combined resistance integrated level of high accuracy in the present invention is high, it is easy to build, it is easy to extend.
2nd, when the input of the adjustable combined resistance of high accuracy inputs for current source, signal front-end processing circuit can be completed
The conversion of Current Voltage, compared with conventional current voltage conversion circuit, the circuital current flows into signal ground, will not be to subsequent conditioning circuit
Produce influence.
3rd, the Auto-Test System and method based on the adjustable combined resistance of high accuracy in the present invention, using universal meter and PC
Machine realizes System self-test, compared with conventional test methodologies, and automaticity is high, and the automatic measurement of data can be achieved, gathers and divides
Analysis, eliminates the error of manual test, improves equipment precision.
The adjustable combined resistance of high accuracy of the present invention can be simultaneously in voltage signal input and current signal input two
Worked under the state of kind, without changing circuit structure.Therefore, the complexity and cost of product realization are reduced.Employ simultaneously
High-precision integrated AD/DA boards, its precision reaches 0.002%, it is ensured that the automatic test system of high-precision adjustable combined resistance
The overall precision of system.The present disclosure additionally applies for the automatic test of other resistance and resistance.
Brief description of the drawings
Fig. 1 is the structural representation of the adjustable combined resistance of high accuracy；
Fig. 2 is the circuit connecting relation figure of the Auto-Test System of the adjustable combined resistance of high accuracy.
Embodiment
Embodiment one, reference picture 1 illustrate present embodiment, and the high accuracy described in present embodiment can be concocted
Into resistance, it includes input terminal A0, No. two input terminal B0, signal front-end processing circuit 1, an integrated AD/DA plates
Card 2, source of stable pressure 3 and central processing unit 4；
Signal front-end processing circuit 1 includes sampling resistor Rb and operational amplifier A；Sampling resistor Rb one end concatenation operation
Amplifier A electrode input end；The negative input of operational amplifier A concatenation operation amplifier A output end and integrated simultaneously
The AD signal input parts of AD/DA boards 2；The cathode power supply output of the cathode power supply input connection source of stable pressure 3 of operational amplifier A
End；The negative power supply input of operational amplifier A connects the negative power supply output end of source of stable pressure 3；
Number input terminal A0 connection sampling resistors Rb one end；Sampling resistor Rb other end ground connection；No. two inputs
The DA signal input parts of the integrated AD/DA boards 2 of terminals B0 connections；
The AD/DA signal input output ends of central processing unit 4 connect the AD/DA signal outputs input of integrated AD/DA boards 2
End.
The basic functional principle and application method of combined resistance be：According to an input terminal A0 and No. two input wires
Hold B0 input signal, regulation port voltage (difference of an input terminal A0 and No. two input terminal B0 input signal)
With the ratio of electric current, carry out simulation output resistance R.According to Fig. 1, the input voltage U=Ua-Ub of combined resistance, input current
For I, equivalent output resistance R=U/I=(Ua-Ub)/I.
Below in two kinds of situation, the course of work of combined resistance is introduced：
1st, input signal is voltage signal
When the input signal of combined resistance is voltage signal, port voltage U is fixed value, and equivalent output resistance passes through
Change electric current I to adjust.According to Fig. 1, the output current I=Ua/Rb, Rb of combined resistance are the bases in signal front-end processing circuit
Quasi- resistance.Ub is the output voltage of the DA signals in integrated AD/DA boards.Ua-Ub is a fixed value U, when adjusting Ub, Ua
It can therewith change, and then electric current I is also changed therewith, it is achieved thereby that the purpose of regulation output resistance.
Keep input terminal A0 input voltage signal and No. two input terminal B0 input voltage signal
Difference is a value U admittedly, is inputted by central processing unit 4 and integrated AD/DA boards 2 to No. two input terminal B0 adjustable
Voltage signal Ub, according to the input voltage U=Ua-Ub of combined resistance, it is known that Ua values change and changed with Ub；Again according to synthesis electricity
The output current I=Ua/Rb of resistance, it is known that now the output current I of combined resistance changes and changed with Ua；Again according to combined resistance
R=U/I=(Ua-Ub)/I, now combined resistance R size with combined resistance output current I change and change, that is, obtain can
It is mixed into resistance R.
2nd, input signal is current signal
When the input signal of combined resistance is current signal, input current I is fixed value, and equivalent output resistance passes through
Change port voltage U to adjust.Due to I=Ua/Rb, when I is fixed, voltage Ua also immobilizes.Again according to formula U=Ua-
Ub, if wanting to obtain the port voltage U of change, directly adjusts the output voltage Ub of the DA signals in integrated AD/DA boards, you can adjust
The port voltage U of combined resistance is saved, so as to realize the purpose of regulation output resistance.
It is fixed value to keep input current I, by central processing unit 4 and integrated AD/DA boards 2 to No. two input terminals
B0 inputs adjustable voltage signal Ub, according to the output current I=Ua/Rb of combined resistance, it is known that now Ua immobilizes；Again
According to the input voltage U=Ua-Ub of combined resistance, it is known that U changes and changed with Ub；Again according to combined resistance R=U/I=(Ua-
Ub)/I, now combined resistance R size change with the change of the input voltage of combined resistance, that is, obtain adjustable combined resistance
R。
It can be known by above-mentioned operation principle, by adjusting the size of input signal, realize the output to combined resistance
The regulation of resistance, and then precision resister is obtained, realize high accuracy adjustable.
In present embodiment, source of stable pressure is power supply, for being powered for signal front-end processing circuit.
Signal front-end processing circuit is used for signal acquisition, conversion and isolated, when in an input terminal A0 and No. two
During input terminal B0 input voltage signals, signal front-end processing circuit is automatically performed following for voltage signal；When defeated at No. one
When entering terminals A0 and No. two input terminal B0 input current signals, signal front-end processing circuit is automatically performed electric current to voltage
Conversion.
Central processing unit 4 is used for the resistance of the voltage and setting combined resistance according to the AD port processings of integrated AD/DA boards 2
The DA outputs of the integrated AD/DA boards 2 of value control, so as to realize regulation output voltage Ub purpose.
Embodiment two, the automatic test system based on the adjustable combined resistance of high accuracy described in embodiment one
System, the system also includes PC 5, a universal meter 6 and No. two universal meters 7；Embedded signal processing module 5-1 in PC 5；
Two output ends of a number universal meter 6 connect sampling resistor Rb two ends respectively；The two ends difference of No. two universal meters 7
Connect an input terminal A0 and No. two input terminal B0；Connected between a number universal meter 6 and PC 5 by serial ports；Two
Number connected between universal meter 7 and PC 5 by serial ports；
Signal processing module 5-1 is used to gathering, store and handling the data that a universal meter 6 and No. two universal meters 7 are gathered.
In present embodiment, a universal meter 6 and No. two universal meters 7 are the type universal meter of model 34401.It is worked
Journey：Two universal meters measure the voltage and current of combined resistance respectively, and measurement result is sent into PC 5, PC by serial ports
The storage and processing of measurement result are completed in machine 5, automatic test is realized.
The Auto-Test System of the adjustable combined resistance of high accuracy described in embodiment three, present embodiment it is automatic
Method of testing, the automatic test approach comprises the steps：
Step 1: adding between an input terminal A0 and No. two input terminal B0 for the adjustable combined resistance of high accuracy
Enter test and excitation, test and excitation is voltage source or current source；
Step 2: measuring the electric current of input using a universal meter 6, the voltage of input is measured using No. two universal meters 7；
Step 3: the serial ports parameter of a universal meter 6 and No. two universal meters 7 is set, including serial port baud rate and odd even school
Position is tested, while setting the serial ports parameter of signal processing module 5-1 in PC 5, distinguishes signal processing module 5-1 serial ports parameter
It is consistent with the serial ports parameter of a universal meter 6 and No. two universal meters 7；
Step 4: setting time of measuring interval and time of measuring by the signal processing module 5-1 in PC 5, and connect
A number universal meter 6 and No. two universal meters 7 are at remote state, start test；
Step 5: the signal processing module 5-1 in PC 5 gathers the voltage that a universal meter 6 and No. two universal meters 7 are measured
Data or current data, and voltage data or current data are included on PC 5 in graphical form；Meanwhile, signal transacting mould
Block 5-1 does average value processing to voltage data or current data, obtains average voltage and current average, average voltage and electricity
Levelling average is divided by as final measurement resistance value.
In present embodiment, the serial ports parameter of the signal processing module 5-1 in step 3 respectively with a universal meter 6 and two
The serial ports parameter of number universal meter 7 is consistent, can also be expressed as when using a universal meter 6, signal processing module 5-1 serial ports ginseng
Number sets consistent with a universal meter 6, when using No. two universal meters 7, signal processing module 5-1 serial ports parameter setting and two
Number universal meter 7 is consistent.
The advantage of the automatic test approach is：
A. the resistance of the adjustable combined resistance of automatic test high accuracy, eliminates cumbersome manual measurement, it is to avoid artificial survey
Measure the error introduced.
B. voltage data and current data are automatically processed by signal processing module 5-1, eliminates the rings such as temperature
The influence of border factor, makes measurement more accurate.
Embodiment four, present embodiment are to the adjustable combined resistance of high accuracy described in embodiment three
The automatic test approach of Auto-Test System is further illustrated, in present embodiment, number universal meter 6 of use in step 2
The electric current of measurement input is that input current is converted into voltage realization measurement by sampling resistor.
Embodiment five, present embodiment are one embodiment.
The adjustable combined resistance of high accuracy, it includes an input terminal A0, No. two input terminal B0, at signal front end
Manage circuit 1, integrated AD/DA boards 2, source of stable pressure 3 and central processing unit 4；
Signal front-end processing circuit 1 includes sampling resistor Rb and operational amplifier A；Sampling resistor Rb one end concatenation operation
Amplifier A electrode input end；The negative input of operational amplifier A concatenation operation amplifier A output end and integrated simultaneously
The AD signal input parts of AD/DA boards 2；The cathode power supply output of the cathode power supply input connection source of stable pressure 3 of operational amplifier A
End；The negative power supply input of operational amplifier A connects the negative power supply output end of source of stable pressure 3；
Number input terminal A0 connection sampling resistors Rb one end；Sampling resistor Rb other end ground connection；No. two inputs
The DA signal input parts of the integrated AD/DA boards 2 of terminals B0 connections；
The DA signal input output ends of central processing unit 4 connect the DA signal output inputs of integrated AD/DA boards 2.
The model CB-68LP expansion board of integrated AD/DA boards；Source of stable pressure is SS3323 source of stable pressure；Central processing unit is
Realize that data transfer is real by the boards of PXI 6221 with integrated AD/DA boards in NI PXI8108 processors, central processing unit
Existing.
Claims (3)
1. based on the Auto-Test System of the adjustable combined resistance of high accuracy, the adjustable combined resistance of high accuracy includes an input
Terminals (A0), No. two input terminals (B0), signal front-end processing circuit (1), integrated AD/DA boards (2), source of stable pressure (3)
With central processing unit (4)；
Signal front-end processing circuit (1) includes sampling resistor Rb and operational amplifier (A)；Sampling resistor Rb one end concatenation operation
The electrode input end of amplifier (A)；The negative input of operational amplifier (A) is while the output end of concatenation operation amplifier (A)
With the AD signal input parts of integrated AD/DA boards (2)；The cathode power supply input connection source of stable pressure (3) of operational amplifier (A)
Cathode power supply output end；The negative power supply output end of the negative power supply input connection source of stable pressure (3) of operational amplifier (A)；
Number input terminal (A0) connection sampling resistor Rb one end；Sampling resistor Rb other end ground connection；No. two inputs connect
Line end (B0) connects the DA signal input parts of integrated AD/DA boards (2)；
The AD/DA signal input output ends of central processing unit (4) connect the AD/DA signal outputs input of integrated AD/DA boards (2)
End；
Characterized in that, the Auto-Test System also includes PC (5), a universal meter (6) and No. two universal meters (7)；PC
Embedded signal processing module (5-1) in machine (5)；
Two output ends of a number universal meter (6) connect sampling resistor Rb two ends respectively；The two ends difference of No. two universal meters (7)
Connect an input terminal (A0) and No. two input terminals (B0)；Pass through serial ports between a number universal meter (6) and PC (5)
Connection；It is connected between No. two universal meters (7) and PC (5) by serial ports；
Signal processing module (5-1) is used for the number for gathering, storing and handling a universal meter (6) and No. two universal meter (7) collections
According to.
2. the automatic test approach of the Auto-Test System according to claim 1 based on the adjustable combined resistance of high accuracy,
Characterized in that, the automatic test approach comprises the steps：
Step 1: adding between an input terminal (A0) and No. two input terminals (B0) for the adjustable combined resistance of high accuracy
Enter test and excitation, test and excitation is voltage source or current source；
Step 2: measuring the electric current of input using a universal meter (6), the voltage of input is measured using No. two universal meters (7)；
Step 3: the serial ports parameter of a universal meter (6) and No. two universal meters (7) is set, including serial port baud rate and odd even school
Position is tested, while setting the serial ports parameter of signal processing module (5-1) in PC (5), joins the serial ports of signal processing module (5-1)
Number is consistent with the serial ports parameter of a universal meter (6) and No. two universal meters (7) respectively；
Step 4: setting time of measuring interval and time of measuring by the signal processing module (5-1) in PC (5), and connect
A number universal meter (6) and No. two universal meters (7) are at remote state, start test；
Step 5: what signal processing module (5-1) number universal meter (6) of collection and No. two universal meters (7) in PC (5) measured
Voltage data or current data, and voltage data or current data are included on PC (5) in graphical form；Meanwhile, signal
Processing module (5-1) does average value processing to voltage data or current data, obtains average voltage and current average, and voltage is put down
Average and current average are divided by as final measurement resistance value.
3. the automatic test approach of the Auto-Test System according to claim 2 based on the adjustable combined resistance of high accuracy,
Characterized in that, the electric current of number universal meter (6) the measurement input of use in step 2 is that input current is turned by sampling resistor
Change voltage into and realize measurement.
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Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201237611Y (en) * | 2008-05-14 | 2009-05-13 | 张蒙 | Multifunctional high-precision resistor signal generator |
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2015
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Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201237611Y (en) * | 2008-05-14 | 2009-05-13 | 张蒙 | Multifunctional high-precision resistor signal generator |
Non-Patent Citations (2)
| Title |
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| "基于DSP的便携式过程校验仪的研究与设计";马扬龙;《中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑》;20140415(第04期);第C042-678页 * |
| "用于电阻类传感器校准的电子合成电阻";张天宏 等;《传感器技术》;20041020;第23卷(第10期);第53-59页 * |
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