CN109459067A - A kind of method of sensor accuracy compensation - Google Patents

A kind of method of sensor accuracy compensation Download PDF

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Publication number
CN109459067A
CN109459067A CN201811643557.1A CN201811643557A CN109459067A CN 109459067 A CN109459067 A CN 109459067A CN 201811643557 A CN201811643557 A CN 201811643557A CN 109459067 A CN109459067 A CN 109459067A
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temperature
groups
sensor
correction factor
sensitivity
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CN201811643557.1A
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Inventor
王小岗
刘建群
付海亮
周智荣
李文渊
王晓东
陈益强
李永强
张锐
孙光文
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Zhonghang Electronic Measuring Instruments Co Ltd
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Zhonghang Electronic Measuring Instruments Co Ltd
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D3/00—Indicating or recording apparatus with provision for the special purposes referred to in the subgroups
    • G01D3/028—Indicating or recording apparatus with provision for the special purposes referred to in the subgroups mitigating undesired influences, e.g. temperature, pressure
    • G01D3/036—Indicating or recording apparatus with provision for the special purposes referred to in the subgroups mitigating undesired influences, e.g. temperature, pressure on measuring arrangements themselves
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D18/00—Testing or calibrating apparatus or arrangements provided for in groups G01D1/00 - G01D15/00

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Indication And Recording Devices For Special Purposes And Tariff Metering Devices (AREA)

Abstract

The invention discloses a kind of method of sensor accuracy compensation, the compensation including zero temperature drift includes the following steps；1. debugging sensor is placed under three groups of different temperatures environment, three groups of temperature are measured using debugging sensor, code value AD_Z1, AD_Z2 and AD_Z3 of the offset output value at a temperature of obtaining three groups；2. according to the code value of zero temperature drift, the difference △ AD_Zt of the offset output value of the difference △ Zt and each temperature of corresponding observed temperature value at a temperature of calculating each group；3. the data of step 1 and step 2 are calculated the correction factor of zero temperature drift by least square method；4. the correction factor of zero temperature drift is input in sensor, compensation is completed.It is limited to solve accuracy compensation present in existing analog compensation technology, complex process needs repeatedly to calibrate repeatedly, production cycle longer problem.

Description

A kind of method of sensor accuracy compensation
Technical field
The invention belongs to sensor accuracies to compensate field, be related to a kind of method of sensor accuracy compensation.
Background technique
There is zero temperature drift (ZTC) in all sensors.Sometimes the drift of sensor can make entirely to measure or control System processed can not work normally, in order to reduce the influence that drift exports sensor, current existing analog sensed to greatest extent Device and digital sensor are all made of mechanical system and compensate to the drift of sensor.
The compensation method of zero temperature drift is that the mode of the welding kesistance silk in Wheatstone bridge road compensates calibration.Often Secondary compensation need to repeatedly carry out high/low temperature circulating temperature acquisition, later according to the resistance of compensation data calculation, according to the resistance of calculating The resistance wire for welding corresponding length needs the repeated multiple times precision for compensating and can be only achieved needs, every time the compensation used time 3~5 days.Take When it is laborious, usual accuracy compensation is only capable of reaching 0.02%F.S.Accuracy compensation is limited, complex process, needs repeatedly to calibrate repeatedly, Production cycle is longer
Summary of the invention
It is an object of the invention to overcome the above-mentioned prior art, a kind of method of sensor accuracy compensation is provided, It is limited to solve accuracy compensation present in existing analog compensation technology, complex process needs repeatedly to calibrate repeatedly, the production cycle Longer problem.
In order to achieve the above objectives, the present invention is achieved by the following scheme:
A kind of method of sensor accuracy compensation, the compensation including zero temperature drift include the following steps；
Step 1, will debugging sensor be placed under three groups of different temperatures environment, using debugging sensor to three groups of temperature into Row measurement, code value AD_Z1, AD_Z2 and AD_Z3 of the offset output value at a temperature of obtaining three groups；
Step 2, according to the code value of zero temperature drift, calculate at a temperature of each group the difference △ Zt of corresponding observed temperature value and The difference △ AD_Zt of the offset output value of each temperature；
Step 3, by the data of step 1 and step 2, the correction factor of zero temperature drift is calculated by least square method；
Step 4, the correction factor of zero temperature drift is input in sensor, completes compensation.
Preferably, the difference △ of the sensitivity output valve of the difference △ Zt and each temperature of observed temperature value corresponding at each temperature AD_Zt is
△ Zt=Zt-Ztn
△ AD_Zt=AD_Zt-AD_Ztn
Zt is temperature, ZtnFor any one group of temperature selected in three groups, three groups of temperature are substituted into Zt, by three groups of zero points The code value of output substitutes into AD_Zt, obtains three groups of △ Zt and △ AD_Zt.
Further, the correction factor of zero temperature drift is calculated by least square method
△ AD_Zt=Kz2 △ Zt2+Kz1△Zt+Kz0
Three groups of △ t and △ AD_St are substituted into formula respectively, obtain three groups of formula, wherein Kz0 is initial position amendment system Number, Kz1 are linear correction factor, and Kz2 is curvature correction factor.
Preferably, further include the compensation of sensitivity temperature drift, include the following steps；
Step 1, will debugging sensor be placed under four groups of different temperatures environment, using debugging sensor to four groups of temperature into Row measurement, code value AD_S1, AD_S2, AD_S3 and AD_S4 of the sensitivity output at a temperature of obtaining four groups；
Step 2, the code value exported according to sensitivity calculates at a temperature of each group corresponding observed temperature value ratio △ St and each The sensitivity of temperature exports ratio △ AD_St；
Step 3, data step 1 and step 2 obtained pass through the amendment of least square method meter sensitivity temperature drift Coefficient；
Step 4, the correction factor of sensitivity temperature drift is input in debugging sensor, completes compensation.
Further, the correction factor of sensitivity temperature drift is input in remaining sensor of same production batch, it is right Remaining sensor compensates.
Further, the code value ratio of the sensitivity output of observed temperature value ratio △ St corresponding at each temperature and each temperature △ AD_St is
△ St=(St-Stn)/Stn
△ AD_St=(AD_St-AD_Stn)/AD_Stn
St is temperature, StnFor any one group of temperature selected in four groups, four groups of temperature are substituted into St, it is sensitive by four groups The code value of degree output substitutes into St, obtains four groups of △ St and △ AD_St.
Further, pass through the correction factor of least square method meter sensitivity temperature drift
△ AD_St=Ks3 △ St3+Ks2△St2+Ks1△St+Ks0
Four groups of △ St and △ AD_St are substituted into formula respectively, obtain four groups of formula, wherein Ks0 is initial position amendment Coefficient, Ks1 are linear correction factor, and Ks2 is that curvature slightly repairs coefficient, and Ks3 is curvature refine coefficient.
Preferably, further include the compensation of linear coefficient, include the following steps；
Step 1, set loaded weight as Wf, will debugging sensor according to Wf × (1/n), Wf × (2/n) ... Wf is added Carry, corresponding AD value be AD_1, AD_2 ..., AD_n, n >=3；
Step 2, data step 1 obtained calculate linear correction factor by least square method.
Further, linear correction factor is calculated by least square method
AD_LM=Kw2 × AD_x2+Kw1×AD_x+Kw0
Wherein, x=1,2 ..., n, AD_LM is theory AD code value, and Kw0 is initial position correction factor, and Kw1 is linearly repairs Positive coefficient, Kw2 are curvature correction factor.
Compared with prior art, the invention has the following advantages:
The present invention measures sensor to three groups of temperature, and output switchs to digital signal, obtains corresponding offset output Code value the correction factor for calculating zero temperature drift is fitted by least square method in conjunction with actual temperature, will amendment system Number is input in debugging sensor, is completed zero temperature drift compensation, is promoted the precision of sensor significantly, precision can reach Total temperature section C3, reaches 0.01%F.S, does not need to carry out artificial compensation, simple process greatly reduces compensation cycle.
Further, sensor measures four groups of temperature, output switchs to digital signal, and it is defeated to obtain corresponding sensitivity Code value out is fitted the correction factor of meter sensitivity temperature drift by least square method in conjunction with actual temperature, will repair Positive coefficient is input in debugging sensor, is completed sensitivity temperature drift compensation, is promoted the precision of sensor significantly, precision It can reach total temperature section C3, reach 0.01%F.S, do not need to carry out artificial compensation, simple process greatly reduces compensation week Phase.
Further, since the processing of same production batch elastomer, the material of sensor production, technique are consistent, meter The correction factor for calculating the sensitivity temperature drift of a sensor, all the sensors being applicable in same production batch, The correction factor of sensitivity temperature drift is input in remaining sensor of same production batch, just can be realized to remaining biography The sensitivity temperature drift of sensor compensates, and greatly improves compensation efficiency.
Further, sensor loads multiple groups weight, output switchs to digital signal, obtains corresponding AD value, ties Actual weight and loaded weight theoretical coefficient are closed, is fitted by least square method and calculates linear correction factor, is by amendment Number is input in debugging sensor, is completed linear compensation, is promoted the precision of sensor significantly, simple process greatly reduces Compensation cycle.
Detailed description of the invention
Fig. 1 is the flow diagram of zero temperature drift of the present invention compensation；
Fig. 2 is the flow diagram of sensitivity temperature drift of the present invention compensation；
Fig. 3 is the flow diagram of linear compensation of the present invention.
Specific embodiment
The invention will be described in further detail with reference to the accompanying drawing:
As shown in Figure 1, the compensation of sensor zero point temperature drift ZTC, includes the following steps；
Step 1, debugging sensor is placed under three groups of different temperatures environment, the present embodiment preferably three groups of temperature are respectively 5 DEG C, 20 DEG C and 30 DEG C, three groups of temperature are measured using debugging sensor, the offset output value at a temperature of obtaining three groups Code value AD_Z05, AD_Z20 and AD_Z30；
Step 2, according to the code value of zero temperature drift, calculate at a temperature of each group the difference △ Zt of corresponding observed temperature value and The difference △ AD_Zt of the offset output value of each temperature；
△ Zt=Zt-Ztn
△ AD_Zt=AD_Zt-AD_Ztn
Zt is temperature, ZtnFor any one group of temperature selected in three groups, the preferred Zt of the present embodimentnIt is 20 DEG C, AD_ZtnFor AD_Z20 substitutes into three groups of temperature in Zt, and the code value of three groups of offset outputs is substituted into AD_Zt, three groups of △ Zt and △ AD_ are obtained Zt。
Step 3, by the data of step 1 and step 2, the correction factor of zero temperature drift is calculated by least square method；
△ AD_Zt=Kz2 △ Zt2+Kz1△Zt+Kz0
Three groups of △ t and △ AD_St are substituted into formula respectively, obtain three groups of formula, wherein Kz0 is initial position amendment system Number, Kz1 are linear correction factor, and Kz2 is curvature correction factor.
Step 4, the correction factor of zero temperature drift is input in sensor, completes compensation.
As shown in Fig. 2, the compensation of sensor sensitivity temperature drift STC, includes the following steps；
Step 1, debugging sensor is placed under four groups of different temperatures environment, the present embodiment preferably four groups of temperature are respectively 5 DEG C, 20 DEG C, 30 DEG C and 40 DEG C, four groups of temperature are measured using debugging sensor, the sensitivity at a temperature of obtaining four groups is defeated Code value AD_S05, AD_S20, AD_S30 and AD_S40 out.
Step 2, the code value exported according to sensitivity calculates at a temperature of each group corresponding observed temperature value ratio △ St and each The sensitivity of temperature exports ratio △ AD_St；
△ St=(St-Stn)/Stn
△ AD_St=(AD_St-AD_Stn)/AD_Stn
St is temperature, StnFor any one group of temperature selected in four groups, the preferred St of the present embodimentnIt is 20 DEG C, AD_StnFor AD_S20 substitutes into four groups of temperature in St, and the code value of four groups of sensitivity outputs is substituted into St, four groups of △ St and △ AD_ are obtained St。
Step 3, data step 1 and step 2 obtained pass through the amendment of least square method meter sensitivity temperature drift Coefficient；
△ AD_St=Ks3 △ St3+Ks2△St2+Ks1△St+Ks0
Four groups of △ St and △ AD_St are substituted into formula respectively, obtain four groups of formula, wherein Ks0 is initial position amendment Coefficient, Ks1 are linear correction factor, and Ks2 is that curvature slightly repairs coefficient, and Ks3 is curvature refine coefficient.
Step 4, four correction factors of sensitivity temperature drift are input in all the sensors of same production batch, Complete compensation.
As shown in figure 3, the compensation of pickup wire property coefficient, includes the following steps；
Step 1, set loaded weight as Wf, will debugging sensor according to Wf × (1/n), Wf × (2/n) ... Wf is added Carry, corresponding AD value be AD_1, AD_2 ..., AD_n, n >=3；
Step 2, data step 1 obtained calculate linear correction factor by least square method
AD_LM=Kw2 × AD_x2+Kw1×AD_x+Kw0
Wherein, x=1,2 ..., n, AD_LM is theory AD code value, and Kw0 is initial position correction factor, and Kw1 is linearly repairs Positive coefficient, Kw2 are curvature correction factor.
The example of the compensation of pickup wire property coefficient is as follows, and full Cheng Chongliang Wf, current zero point corresponding A D value is AD_Z20, right AD_F, Kf=AD_F/Wf should be exported
If currently given weight is W, AD_LM=W × Kf+AD_Z20
As shown in table 1: the target AD code value of load 10kg output is 50000, Kf=5000
Take 0kg point, AD_LM=AD_Z20
2.5kg point is taken, theoretical AD code value output at this time is AD_LM=2.5 × 5000+AD_Z20
Weight Target code value (y) Actual acquisition code value (x)
10kg 50000+AD_Z20 AD_10
2.5kg 2.5×Kf+AD_Z20 AD_2.5
0kg AD_Z20 AD_0
Data in table 1 are substituted into formula AD_LM=Kw2 × AD_x2In+Kw1 × AD_x+Kw0, solution obtain Kw2, Kw1、Kw0。
The above content is merely illustrative of the invention's technical idea, and this does not limit the scope of protection of the present invention, all to press According to technical idea proposed by the present invention, any changes made on the basis of the technical scheme each falls within claims of the present invention Protection scope within.

Claims (9)

1. a kind of method of sensor accuracy compensation, which is characterized in that the compensation including zero temperature drift, including following step Suddenly；
Step 1, debugging sensor is placed under three groups of different temperatures environment, three groups of temperature is surveyed using debugging sensor Amount, code value AD_Z1, AD_Z2 and AD_Z3 of the offset output value at a temperature of obtaining three groups；
Step 2, according to the code value of zero temperature drift, difference the △ Zt and Ge Wen of corresponding observed temperature value at a temperature of each group are calculated The difference △ AD_Zt of the offset output value of degree；
Step 3, by the data of step 1 and step 2, the correction factor of zero temperature drift is calculated by least square method；
Step 4, the correction factor of zero temperature drift is input in sensor, completes compensation.
2. a kind of method of sensor accuracy compensation according to claim 1, which is characterized in that reality corresponding at each temperature The difference △ AD_Zt of the sensitivity output valve of the difference △ Zt and each temperature of thermometric angle value is
△ Zt=Zt-Ztn
△ AD_Zt=AD_Zt-AD_Ztn
Zt is temperature, ZtnFor any one group of temperature selected in three groups, three groups of temperature are substituted into Zt, by three groups of offset outputs Code value substitutes into AD_Zt, obtains three groups of △ Zt and △ AD_Zt.
3. a kind of method of sensor accuracy compensation according to claim 2, which is characterized in that pass through least square method meter Calculate the correction factor of zero temperature drift
△ AD_Zt=Kz2 △ Zt2+Kz1△Zt+Kz0
Three groups of △ t and △ AD_St are substituted into formula respectively, obtain three groups of formula, wherein Kz0 is initial position correction factor, Kz1 is linear correction factor, and Kz2 is curvature correction factor.
4. a kind of method of sensor accuracy compensation according to claim 1, which is characterized in that further include sensitivity temperature The compensation of drift, includes the following steps；
Step 1, debugging sensor is placed under four groups of different temperatures environment, four groups of temperature is surveyed using debugging sensor Amount, code value AD_S1, AD_S2, AD_S3 and AD_S4 of the sensitivity output at a temperature of obtaining four groups；
Step 2, the code value exported according to sensitivity calculates corresponding observed temperature value ratio △ St and each temperature at a temperature of each group Sensitivity export ratio △ AD_St；
Step 3, data step 1 and step 2 obtained pass through the amendment system of least square method meter sensitivity temperature drift Number；
Step 4, the correction factor of sensitivity temperature drift is input in debugging sensor, completes compensation.
5. a kind of method of sensor accuracy compensation according to claim 4, which is characterized in that by sensitivity temperature drift Correction factor be input in remaining sensor of same production batch, remaining sensor is compensated.
6. a kind of method of sensor accuracy compensation according to claim 4, which is characterized in that reality corresponding at each temperature The code value ratio △ AD_St of the sensitivity output of thermometric angle value ratio △ St and each temperature is △ St=(St-Stn)/Stn
△ AD_St=(AD_St-AD_Stn)/AD_Stn
St is temperature, StnFor any one group of temperature selected in four groups, four groups of temperature are substituted into St, four groups of sensitivity are exported Code value substitute into St in, obtain four groups of △ St and △ AD_St.
7. a kind of method of sensor accuracy compensation according to claim 6, which is characterized in that pass through least square method meter Calculate the correction factor of sensitivity temperature drift
△ AD_St=Ks3 △ St3+Ks2△St2+Ks1△St+Ks0
Four groups of △ St and △ AD_St are substituted into formula respectively, obtain four groups of formula, wherein Ks0 is initial position correction factor, Ks1 is linear correction factor, and Ks2 is that curvature slightly repairs coefficient, and Ks3 is curvature refine coefficient.
8. a kind of method of sensor accuracy compensation according to claim 1, which is characterized in that further include linear coefficient Compensation, includes the following steps；
Step 1, set loaded weight as Wf, will debugging sensor according to Wf × (1/n), Wf × (2/n) ... Wf is loaded, Corresponding AD value be AD_1, AD_2 ..., AD_n, n >=3；
Step 2, data step 1 obtained calculate linear correction factor by least square method.
9. a kind of method of sensor accuracy compensation according to claim 1, which is characterized in that pass through least square method meter Calculate linear correction factor
AD_LM=Kw2 × AD_x2+Kw1×AD_x+Kw0
Wherein, x=1,2 ..., n, AD_LM is theory AD code value, and Kw0 is initial position correction factor, and Kw1 is that linear amendment is Number, Kw2 is curvature correction factor.
CN201811643557.1A 2018-12-29 2018-12-29 A kind of method of sensor accuracy compensation Pending CN109459067A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111256744A (en) * 2020-02-27 2020-06-09 苏州海之博电子科技有限公司 Calibration method of linear output position sensor
CN113588063A (en) * 2021-07-28 2021-11-02 天津市府易科技股份有限公司 Detection system of going out based on living body gravity induction and edge intelligent recognition technology

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111256744A (en) * 2020-02-27 2020-06-09 苏州海之博电子科技有限公司 Calibration method of linear output position sensor
CN111256744B (en) * 2020-02-27 2021-06-29 苏州海之博电子科技有限公司 Calibration method of linear output position sensor
CN113588063A (en) * 2021-07-28 2021-11-02 天津市府易科技股份有限公司 Detection system of going out based on living body gravity induction and edge intelligent recognition technology

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