CN205582652U - Compensation hardware error influence's high accuracy passive resistance generator - Google Patents
Compensation hardware error influence's high accuracy passive resistance generator Download PDFInfo
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- CN205582652U CN205582652U CN201620410215.5U CN201620410215U CN205582652U CN 205582652 U CN205582652 U CN 205582652U CN 201620410215 U CN201620410215 U CN 201620410215U CN 205582652 U CN205582652 U CN 205582652U
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Abstract
The utility model provides a compensation hardware error influence's high accuracy passive resistance generator, includes the main control unit, connects the resistance network and the resistance measurement unit of main control unit, resistance network includes a M series resistance, corresponds a parallelly connected M normally closed relay and control the M relay drive circuit of corresponding relay switching with each resistance, and relay drive circuit connects the main control unit, the resistance of each resistance among the main control unit receipt resistance measurement unit measuring resistance network to through the corresponding relay switching of relay drive circuit control, will correspond parallelly connected resistance and arrange in and open a way or short -circuit state. The utility model provides a current passive resistance generator output precision depend on the resistance precision completely and export the problem that the precision is low, can satisfy in the in -service use required precision to the passive resistance ware.
Description
Technical field
This utility model relates to the fields such as instrument and meter calibration, circuit test, is about a kind of height compensating hardware error impact
Precision passive resistance generator.
Background technology
Resistance generator is as the important a reference source in the fields such as instrument and meter calibration, circuit test, and its precision index is particularly important.
Existing precision resister generator mainly includes electronic type active adjustable resistance device and digitized passive resistance two kinds.Wherein, electricity
The preset resistance value of input, based on Ohm's law, is converted into corresponding control signal by processor by minor active adjustable resistance device
Control range change-over circuit and gain setting circuit, to change the voltage of circuit overall output, and then realize the intelligence of resistance value
Regulation.The gain that this resistance method for generation uses DAC chip to realize voltage is amplified, when operating current makes more greatly magnitude of voltage exceed
During the maximum reference voltage of DAC, equivalent resistance will keep constant, and resistor lost efficacy, and the method is limited by operating current,
Shortcomings in terms of versatility.Digitized passive resistance uses single-chip microcomputer or CMOS integrated circuit to control relay switching resistance
Value is the precision resistance combination of 8421 codings, it is achieved passive resistance exports.The method is not limited by operating current, versatility
By force, yet with directly using 8421 way of outputs on the basis of resistance nominal value, dividing the impact of hardware error factor is lacked
Analysis, output accuracy places one's entire reliance upon resistance precision, and during use, device aging will cause the reduction of output accuracy.The method exists
Realize high output accuracy and the robustness aspect still Shortcomings of resistor.
The patent No. is that the Chinese patent of CN200410021628.6 proposes one control and compensates " the programmable standard hesistance generator "
The method of error, the method includes: at most 16 precision resistor Ri(i=1～16), presses binary system rule successively and makes by turn
The resistance network being in series；R is eliminated with " potentiometer in parallel, | a |～| b | plus tolerance band method "1～R16Precision resistance is in coiling
The error brought；Determine RString i, multiturn potentiometer RpiOptimal resistance, each precision resistance position R can be madeiError close to 0 Ω.
The contact resistance error of " the programmable standard hesistance generator " relay contact must be made hardware compensating: normal to relay with N
Closed contact composes in parallel certain group relay normally-closed contact K in relay networki(i=1～16), makes each resistance position normal because of relay
The error that closed contact contact resistance brings within value calculated below (as a example by N=8): 0.05 Ω/8=0.0063 Ω ＜ 0.01 Ω.
This patent can make measuring resistance reach to export absolute error≤0.2 Ω of pure resistance in 0～6553.6 Ω ranges.This patent provides
Although error control and compensation method can effectively overcome resistance foozle and the impact on output accuracy of the relay contact resistance,
But the method need to be by regulation Rpi、RString iValue by high-accuracy resistance RiAdjust to nominal value, to resistance and potentiometer required precision
Height, poor operability, and use tolerance range method to realize the compensation to resistance foozle, 0 class precision high stable speciality need to be used
Micron order copper-manganese resistance is to ensure preferable compensation effect, relatively costly.
Utility model content
Main purpose of the present utility model is to provide a kind of passive high-precision resistance generator compensating hardware error impact, solves
Existing passive resistance generator output accuracy places one's entire reliance upon resistance precision and the low problem of output accuracy, improves passive resistance
Output accuracy.
This utility model is by the following technical solutions and technical measures realize.
A kind of passive high-precision resistance generator compensating hardware error impact, including main control unit, the electricity of connection main control unit
Resistance network and resistance measurement unit, described resistor network includes that M series resistance in parallel M corresponding with each resistance is individual normally closed
Relay and M relay drive circuit of the corresponding relay opening and closing of control, relay drive circuit connects main control unit, master control
Unit receives the resistance of each resistance in the resistor network that resistance measurement unit is measured, and passes through hardware error according to preset resistance value R
Compensation method determines the optimum opening and closing compound mode of M normally closed relay, controls corresponding relay by relay drive circuit and opens
Closing, corresponding resistance in parallel is placed in open circuit or short-circuit condition, output compensates the passive resistance of hardware error impact.
It is also preferred that the left described passive resistance generator also includes the display unit being connected with main control unit, main control unit is according to display
Preset resistance value R of unit conveying, pre-output resistance value R that will be obtained by optimum resistance compound modePre-outputSend to display unit
Show.
It is also preferred that the left described passive resistance generator also includes the memory element being connected with main control unit, memory resistor measuring unit
The resistor network resistance measured.
It is also preferred that the left the series resistance of described resistor network uses nominal value can be combined into random natural number within 1～10
Four radixes, M resistance of multiple order of magnitude.
It is also preferred that the left four radixes that described series resistance uses nominal value to be 1,2,2,5 or 1,2,4,8, and quantity
Level W=10tM resistance, t=...-2 ,-1,0,1,2,3 ....
It is also preferred that the left described resistance measurement unit is circuit tester, circuit tester measurement in the resistor network obtained, each resistance is to adopt
Meansigma methods with Kelvin's four-wire ohm metering system repetitive measurement.
Compared with prior art, this utility model at least has following advantages and a beneficial effect:
This utility model utilizes main control unit to control resistor network, analyzes the hardware error affecting laws to resistance output valve, sets up
The quantitative model of the resistance output simulation equation under the influence of each error coupler, uses BFS method by quantitative model, obtains
To real output value (∑ RM)O is realClosest to the optimum opening and closing compound mode of M normally closed relay of preset resistance value R, relay
Optimum opening and closing compound mode correspondence optimum resistance compound mode N, compensate hardware error impact.By controlling resistor network
Relay drive circuit controls corresponding relay opening and closing, corresponding resistance in parallel is placed in output or short-circuit condition, is effectively mended
Repay the optimum resistance combination of hardware error, the passive resistance after output optimization, it is achieved be not entirely dependent on the high accuracy of resistance precision
Resistance exports, and solves existing passive resistance generator output accuracy and places one's entire reliance upon resistance precision and the low problem of output accuracy,
Disclosure satisfy that actually used in required precision to passive resistance, there is stronger robustness and practicality.
Accompanying drawing explanation
Fig. 1 is the structured flowchart of this utility model embodiment.
Fig. 2 is a part of schematic diagram of the resistor network of this utility model embodiment.
Detailed description of the invention
With embodiment, this utility model is further illustrated below in conjunction with the accompanying drawings.
The actual resistance output valve of passive resistance generator is mainly affected by hardware error intrinsic in resistor network.Error is main
Including: the contact resistance of closing relay and connecting between relay, between relay and resistance in resistance foozle, circuit
Pcb board line resistance R0.Resistance foozle be the resistance actual value that caused by resistance manufacturing process, temperature-coefficient of electrical resistance with
The difference of its nominal value.Relay contact resistance is by many complicated factor shadows such as the resistivity of contact surface material, pressure, forms
Ringing, the repeatedly Guan Bi contact resistance value of different relay single Guan Bi contact resistance values and same relay is the most different, and is
Random error.Pcb board line resistance is mainly caused by PCB layout mode.
For reducing preset resistance value R and real output value (the ∑ R of passive resistance generatori)O is realError, the utility model proposes
A kind of passive high-precision resistance generator compensating hardware error impact, by affecting passive resistance output accuracy key issue
Research, simulate the actual output resistance under each hardware error coupling influence, determine each error affecting laws to output valve,
Search by BFS method can the optimum resistance of most effective compensation each error impact combine according to this rule, it is achieved by mistake
Minimizing of difference impact, it is ensured that resistor output accuracy.
In resistor network of the present utility model select high accuracy, Low Drift Temperature resistance with reduce resistance foozle impact.?
During PCB layout, it then follows lead-in wire, resistance and lead-in wire, outfan lead-out wire etc. between corresponding relay in parallel between series resistance
The shortest layout of circuit and wiring rule are to reduce R0The impact of error, and select contact resistance little and the double-pole pair of electrical endurance length
Throw relay to reduce the impact of this error.
Fig. 1 is the structured flowchart of this utility model embodiment, and Fig. 2 is a part for the resistor network of this utility model embodiment
Schematic diagram.With reference to Fig. 1 and Fig. 2, passive high-precision resistance generator of the present utility model includes main control unit, connects master control list
The resistor network of unit and resistance measurement unit.Resistor network includes that M series resistance in parallel M corresponding with each resistance is individual often
Closing relay and control M relay drive circuit of corresponding relay opening and closing, relay drive circuit connects main control unit.Main
Control unit receives the resistance of each resistance in the resistor network that resistance measurement unit is measured, and passes through hardware by mistake according to preset resistance value R
Difference compensation method determines the optimum opening and closing compound mode of M normally closed relay, and the optimum opening and closing compound mode correspondence of relay is optimum
Resistance compound mode N, controls corresponding relay opening and closing by relay drive circuit, corresponding in parallel resistance is placed in open circuit or
Short-circuit condition, output compensates the passive resistance of hardware error impact.Described obtained by hardware error compensation method that M is normally closed to continue
The optimum opening and closing compound mode of electrical equipment, so determine optimum resistance compound mode N specifically by hardware error to resistance output valve
Affecting laws (i.e. resistance output simulation equation), uses BFS method to obtain.Relay drive circuit receives main
The optimum resistance compound mode signal of control unit output, controls corresponding relay opening and closing, makes corresponding resistance in parallel be placed in open circuit or short
Line state, the passive resistance after output optimization.Passive resistance after this optimization can be with the impact of effective compensation hardware error, it is achieved
Minimizing of error impact, it is ensured that the output accuracy of resistor.
In preferred embodiment of the present utility model, passive resistance generator also includes display unit, display unit and master control list
Unit connect, facilitate user to set preset resistance value R, and flow to main control unit, main control unit according to display unit carry pre-
Put resistance value R, pre-output resistance value R that will be obtained by optimum resistance compound modePre-outputTransmission to display unit shows, side
Just user knows resistor pre-output resistance value R that preset resistance value R of setting is correspondingPre-output。
Further, passive resistance generator can also include memory element, and memory element is connected with main control unit, storage
The resistor network resistance that resistance measurement unit is measured, such as unloaded resistance value R of resistor networkO surveys, m-th resistance in resistor network
Measured value RM surveysDeng.
Resistance measurement unit is preferably high-precision circuit tester, and in resistor network, each resistance preferably employs Kelvin four line electricity
The method that resistance metering system repetitive measurement is averaged obtains.
The series resistance of resistor network uses nominal value can be combined into four radixes of random natural number within 1～10, many
M resistance of the individual order of magnitude.Such as, series resistance 4 that nominal value can be used to be 1,2,2,5 or 1,2,4,8
Radix, order of magnitude W=10t=... 10-2, 10-1, 100, 101, 102, 103... M resistance, t=...-2,
-1,0,1,2,3 ....
Main control unit determines that the hardware error compensation method of optimum resistance compound mode N is:
(1) resistance output simulation equation is set upWherein, (∑ RM)O mouldIt it is the mould of resistor network
Intend output valve, RO surveysRepresent the unloaded resistance value of resistor network,RM surveysIt it is resistor network m-th electricity
The measured value of resistance；
(2) use BFS method to optimize the resistance compound mode of resistor network, compensate the impact of hardware error, makeObtain optimum resistance compound mode N, wherein, XiServe as reasonsThe matrix of composition,
I is XiRower, i=1,2 ..., s, KniFor corresponding to XiAnd it is encoded to niRelay on-off combination, Kni=0 or 1,
Ni is XiAssembly coding number, the matrix that optimum resistance compound mode N is made up of n1～ns, min represents minimum.
It should be noted that the actual output of resistor network is represented by:Wherein,
(∑RM)O is realRepresent the real output value of resistor network, ReFor the not homogeneous mis-tie misclosure value of relay, it is set to resistance output mould
Intend the difference of equation and actual output.
Described employing BFS method determines that the method for resistance compound mode N of optimum resistance network is:
(1) definition byThe matrix of composition is X(H×4), H represents line number, and columns is 4 row, H × 4 >=M, X(H×4)Corresponding
Nominal value be XMark (H × 4)=(S1 × W, S2 × W, S3 × W, S4 × W),
Kni=[Kni1, Kni2, Kni3, Kni4；
(2) by XMark (H × 4)Set up preferable output equation RReason=∑ (S1 × Kni4, S2 × Kni3, S3 × Kni2, S4 ×
Kni1 × W, W=10t, t=-2 ,-1,0,1,2 ... H-3, according to preferable output equation to X(H×4)Resistance combine into
Row coding, sets up resistor group and compiles in collaboration with code table；
(3) compiled in collaboration with code table by resistor group, and obtain the matrix likely solved of F (N) according to BFS method
U=[N1, N2, N3..., Nj...]；
(4) definition F (N)=min (f (Nj)-R),According to
Deep search method searching matrix U successively, obtains f (Nj) minima of-R, corresponding f (Nj) it is RPre-output, to NjIn
Element is compiled in collaboration with code table according to resistor group and is decoded, and i.e. obtains optimum resistance compound mode N.
Embodiment one
The output area setting passive resistance generator as 1.0 Ω～20.0K Ω, resolving power as 0.1 Ω, the resistance of employing is
0.01 Ω～10K Ω, four radixes and the order of magnitude W={0.01 that series resistance selects nominal value to be 1,2,2,5,0.1,
25 resistance of 1,10,100,1000,10000}M=1,2 ..., 25.This embodiment optimizes resistor network
The method of resistance compound mode is:
(1) definition byThe matrix of composition isx11、x21～x74Correspond respectively toNominal value corresponding for X is
Kni=[Kni1, Kni2, Kni3, Kni4]；
(2) by XMarkSet up preferable output equation RReason=∑ (S1 × Kni4, S2 × Kni3, S3 × Kni2, S4 × Kni1×
W, wherein, S1, S2, S3, S4 are respectively 1,2,2,5, encode resistance combination according to preferable output equation, build
Vertical resistor group as shown in table 1 compiles in collaboration with code table；
(3) matrix of all resistance compound modes is obtained according to BFS method
U=[N1, N2, N3..., Nj...]；
(4) definition F (N)=min (f (Nj)-R),According to deeply
Degree searching method searching matrix U successively, obtains f (Nj) minima of-R, corresponding f (Nj) it is RPre-output, to NjIn element
Compile in collaboration with code table according to resistor group to be decoded, i.e. obtain optimum resistance compound mode N.
Table 1 embodiment one resistance assembly coding
| kni1 | kni2 | kni3 | kni4 | RReason | ni |
| 0 | 0 | 0 | 0 | 0 | 0 |
| 1 | 0 | 0 | 0 | 1 | 1 |
| 0 | 1 | 0 | 0 | 2 | 2 |
| 0 | 0 | 1 | 0 | 2 | 3 |
| 1 | 1 | 0 | 0 | 3 | 4 |
| 1 | 0 | 1 | 0 | 3 | 5 |
| 0 | 1 | 1 | 0 | 4 | 6 |
| 0 | 0 | 0 | 1 | 5 | 7 |
| 1 | 1 | 1 | 0 | 5 | 8 |
| 1 | 0 | 0 | 1 | 6 | 9 |
| 0 | 0 | 1 | 1 | 7 | 10 |
| 0 | 1 | 0 | 1 | 7 | 11 |
| 1 | 0 | 1 | 1 | 8 | 12 |
| 1 | 1 | 0 | 1 | 8 | 13 |
| 0 | 1 | 1 | 1 | 9 | 14 |
| 1 | 1 | 1 | 1 | 10 | 15 |
Embodiment two
The output area setting passive resistance generator is selected as 1.0 Ω～1.0M Ω, resolving power as 0.1 Ω, series resistance
Nominal value is four radixes and the order of magnitude W={0.01 of 1,2,4,8,0.1,1,10,100,1000,10000,100000}
32 resistanceM=1,2 ..., 32.The method of the resistance compound mode that this embodiment optimizes resistor network is:
(1) definition byThe matrix of composition isx11、x21～x84Correspond respectively toNominal value corresponding for X is
Kni=[Kni1, Kni2, Kni3, Kni4]；
(2) by XMarkSet up preferable output equation RReason=∑ (S1 × Kni4, S2 × Kni3, S3 × Kni2, S4 × Kni1)×
W, wherein, S1, S2, S3, S4 are respectively 1,2,4,8, encode resistance combination according to preferable output equation, build
Vertical resistor group as shown in table 2 compiles in collaboration with code table；
Table 2 embodiment two resistance assembly coding
| kni1 | kni2 | kni3 | kni4 | RReason | ni |
| 0 | 0 | 0 | 0 | 0 | 0 |
| 1 | 0 | 0 | 0 | 1 | 1 |
| 0 | 1 | 0 | 0 | 2 | 2 |
| 1 | 1 | 0 | 0 | 3 | 3 |
| 0 | 0 | 1 | 0 | 4 | 4 |
| 1 | 0 | 1 | 0 | 5 | 5 |
| 0 | 1 | 1 | 0 | 6 | 6 |
| 1 | 1 | 1 | 0 | 7 | 7 |
| 0 | 0 | 0 | 1 | 8 | 8 |
| 1 | 0 | 0 | 1 | 9 | 9 |
| 0 | 1 | 0 | 1 | 7 | 10 |
(3) matrix of all resistance compound modes is obtained according to BFS method
U=[N1, N2, N3..., Nj ...]；
(4) definition F (N)=min (f (Nj)-R),According to
Deep search method searching matrix U successively, obtains f (Nj) minima of-R, corresponding f (Nj) it is RPre-output, to NjIn unit
Element is compiled in collaboration with code table according to resistor group and is decoded, and i.e. obtains optimum resistance compound mode N.
Below by experimental verification effect of the present utility model.
First initial to system calibration, using precision is 61/2Aligent 34401A High Precision Multimeter as resistance measurement list
Unit, with the resistance of each resistance in Kelvin's four-wire ohm metering system repetitive measurement resistor network, seeks its meansigma methods, minimizes survey
The accuracy that amount lead-in wire, the impact of metering contact resistance are measured with guarantee.After system initially calibrates execution once, resistance generator
Can normally work.For ensureing that the precision of resistance generator is not affected by device aging, can be according to resistance and continue during use
Electrical equipment aging performance is periodically executed calibration process, to ensure the robustness of this resistor.
Experiment is at room temperature carried out, and main control unit dominant frequency is 72MHz, and using precision in resistor network is one thousandth, low temperature
25 resistance of degree coefficient.Use embodiment one, 10000 preset resistance values in the range of experiment extraction 1.0 Ω～20K Ω
As experiment sample, it is sequentially output optimum resistance combination according to resistance output flow process, controls 34401A simultaneously and use Kelvin four
Line mode measures the output valve of each optimum resistance combination, is the serial ports of 9600bps by measurement result and pre-output value by baud rate
Transmission to host computer carries out statistical analysis.In experimental result, preset resistance value and real output value in output area relative by mistake
Difference is as shown in table 3.
Table 3 relative error table
In table 3, preset resistance value R of secondary series and real output value (∑ Ri)O is realRelative error be resistor at output model
Enclosing interior overall relative error, the 3rd row show and determine, by the combination of this utility model optimum resistance, the pre-output resistance that method produces
Value RPre-outputWith the relative error of preset resistance value R, the pre-output determined by this utility model hardware error compensation method is maximum definitely
Error is ± 0.008 Ω.Experiment shows, passive resistance generator of the present utility model is realizing the defeated of 1.0 Ω～20.0K Ω
Going out under the technical specification of scope, 0.1 Ω resolving power, output error is better than ± 0.09 Ω, and output response time is less than 8ms, its
Repeat circuit response time is about 4ms, and the execution time of optimum resistance compound mode is about to use hardware error compensation method to determine
3.6ms.This utility model disclosure satisfy that actually used in required precision to passive resistance, there is stronger robustness and practicality
Property.
Claims (6)
1. the passive high-precision resistance generator compensating hardware error impact, it is characterised in that include main control unit, connection
The resistor network of main control unit and resistance measurement unit, described resistor network includes M series resistance and each resistance pair
Answering M normally closed relay in parallel and control M relay drive circuit of corresponding relay opening and closing, relay drives
Circuit connects main control unit, and main control unit receives the resistance of each resistance in the resistor network that resistance measurement unit is measured, and leads to
Cross relay drive circuit and control corresponding relay opening and closing, corresponding resistance in parallel is placed in open circuit or short-circuit condition.
A kind of passive high-precision resistance generator compensating hardware error impact the most according to claim 1, it is characterised in that
Described passive resistance generator also includes the display unit being connected with main control unit.
A kind of passive high-precision resistance generator compensating hardware error impact the most according to claim 1, it is characterised in that
Described passive resistance generator also includes the memory element being connected with main control unit, the resistance that memory resistor measuring unit is measured
Network resistance.
A kind of passive high-precision resistance generator compensating hardware error impact the most according to claim 1, it is characterised in that
The series resistance of described resistor network use nominal value can be combined into random natural number within 1～10 four radixes,
M resistance of multiple orders of magnitude.
A kind of passive high-precision resistance generator compensating hardware error impact the most according to claim 1, it is characterised in that
Four radixes that described series resistance uses nominal value to be 1,2,2,5 or 1,2,4,8, order of magnitude W=10tM
Individual resistance, t=...-2 ,-1,0,1,2,3 ....
A kind of passive high-precision resistance generator compensating hardware error impact the most according to claim 1, it is characterised in that
Described resistance measurement unit is circuit tester.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106500752A (en) * | 2016-12-09 | 2017-03-15 | 上海仪电汽车电子系统有限公司 | Programmable multichannel network resistance circuit |
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2016
- 2016-05-06 CN CN201620410215.5U patent/CN205582652U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106500752A (en) * | 2016-12-09 | 2017-03-15 | 上海仪电汽车电子系统有限公司 | Programmable multichannel network resistance circuit |
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