CN115184427B - Temperature compensation experiment method applied to pH sensor - Google Patents
Temperature compensation experiment method applied to pH sensor Download PDFInfo
- Publication number
- CN115184427B CN115184427B CN202211102674.3A CN202211102674A CN115184427B CN 115184427 B CN115184427 B CN 115184427B CN 202211102674 A CN202211102674 A CN 202211102674A CN 115184427 B CN115184427 B CN 115184427B
- Authority
- CN
- China
- Prior art keywords
- temperature
- sensor
- temperature compensation
- electrode
- adc
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
- G01N27/28—Electrolytic cell components
- G01N27/30—Electrodes, e.g. test electrodes; Half-cells
- G01N27/302—Electrodes, e.g. test electrodes; Half-cells pH sensitive, e.g. quinhydron, antimony or hydrogen electrodes
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/18—Water
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
- G05B19/042—Programme control other than numerical control, i.e. in sequence controllers or logic controllers using digital processors
- G05B19/0423—Input/output
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F17/00—Digital computing or data processing equipment or methods, specially adapted for specific functions
- G06F17/10—Complex mathematical operations
- G06F17/16—Matrix or vector computation, e.g. matrix-matrix or matrix-vector multiplication, matrix factorization
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
- G06F3/05—Digital input using the sampling of an analogue quantity at regular intervals of time, input from a/d converter or output to d/a converter
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
- H03M1/00—Analogue/digital conversion; Digital/analogue conversion
- H03M1/06—Continuously compensating for, or preventing, undesired influence of physical parameters
- H03M1/0602—Continuously compensating for, or preventing, undesired influence of physical parameters of deviations from the desired transfer characteristic
- H03M1/0604—Continuously compensating for, or preventing, undesired influence of physical parameters of deviations from the desired transfer characteristic at one point, i.e. by adjusting a single reference value, e.g. bias or gain error
- H03M1/0607—Offset or drift compensation
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Mathematical Physics (AREA)
- Pathology (AREA)
- Computational Mathematics (AREA)
- Data Mining & Analysis (AREA)
- Pure & Applied Mathematics (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- Immunology (AREA)
- General Engineering & Computer Science (AREA)
- Mathematical Optimization (AREA)
- Mathematical Analysis (AREA)
- Medicinal Chemistry (AREA)
- Molecular Biology (AREA)
- Computing Systems (AREA)
- Food Science & Technology (AREA)
- Automation & Control Theory (AREA)
- Human Computer Interaction (AREA)
- Electrochemistry (AREA)
- Algebra (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Databases & Information Systems (AREA)
- Software Systems (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
- Apparatus Associated With Microorganisms And Enzymes (AREA)
Abstract
The invention discloses a temperature compensation experiment method applied to a pH sensor, relates to the technical field of water quality monitoring, and solves the technical problems that the pH value monitoring is inaccurate and the water quality safety cannot be accurately and timely early warned because the influence of the liquid pH value on the pH sensor electrode aging and the influence of the environment temperature on the change of the measured liquid pH value are not considered in the prior art; according to the invention, on the basis of the first temperature experiment platform, the ADC temperature compensation model is constructed and obtained in combination with the preset temperature sequence, on the basis of the second temperature experiment platform, the electrode temperature compensation model is constructed and obtained in combination with the preset temperature sequence and the preset pH sequence, and the ADC temperature compensation model and the electrode temperature compensation model can ensure that the pH sensor can automatically perform temperature compensation in the changing construction environment temperature, so that the influence of temperature on the measurement precision is eliminated, and the measurement precision of the pH sensor is further improved.
Description
Technical Field
The invention belongs to the field of water quality monitoring, relates to a temperature compensation technology of a pH sensor, and particularly relates to a temperature compensation experiment method applied to the pH sensor.
Background
The pH sensor is used for detecting the concentration of hydrogen ions in a detected object and converting the hydrogen ions into corresponding usable output signals, is a high-precision pH measuring system, and is suitable for liquid media needing to detect pH.
The existing pH sensor does not have a real temperature compensation function, when the pH sensor is installed on a construction site, due to the influence of the environmental temperature of the construction site, signals of a circuit and an electrode of the pH sensor fluctuate, and the pH value of the measured liquid also changes, so that the pH value is measured inaccurately, and the measurement precision is influenced.
In the prior art, when the pH sensor is subjected to temperature compensation, the influence of the pH value of liquid on the aging of the pH sensor electrode and the influence of the ambient temperature on the change of the pH value of the measured liquid are not considered, and the ambient temperature also has influence on a sensor signal circuit, so that the temperature compensation error of the prior pH sensor is large, the safety decision of pH value monitoring is influenced, and the timely and accurate early warning on the water quality safety cannot be performed; therefore, a temperature compensation experiment method applied to a pH sensor is needed.
Disclosure of Invention
The present invention is directed to solving at least one of the problems of the prior art; therefore, the invention provides a temperature compensation experiment method applied to a pH sensor, which is used for solving the technical problems that the pH value monitoring is inaccurate and the water quality safety cannot be timely and accurately early warned due to the fact that the influence of the liquid pH value on the pH sensor electrode aging and the influence of the environment temperature on the pH value change of the measured liquid are not considered in the prior art.
In order to achieve the above object, a first aspect of the present invention provides a temperature compensation experiment method applied to a pH sensor, including:
placing an onboard temperature chip, an ADC (analog to digital converter) and an MCU (micro control unit) of a pH sensor in a programmable incubator, arranging a temperature probe and a pH electrode of the pH sensor at one side of the outside of the programmable incubator, wherein the pH electrode is used for measuring a pH standard solution; an upper computer is arranged on the other side of the exterior of the programmable constant temperature box, and a first temperature generating experiment platform is constructed; wherein, the upper computer is connected with the pH sensor; the onboard temperature chip is used for measuring the temperature of the pH sensor circuit board, and the onboard temperature chip, the ADC and the MCU are welded on the pH sensor circuit board;
on the basis of a first temperature experiment platform, carrying out temperature loading on a pH sensor according to a preset temperature sequence, acquiring and processing an output temperature and a pH value through an upper computer, obtaining a first output value report, and constructing an ADC temperature compensation model according to the first output value report;
placing a pH electrode, a temperature probe, a pH standard solution and an MCU of a pH sensor in the programmable incubator, and connecting the pH sensor with an upper computer outside the programmable incubator to construct a second temperature experiment platform; in the second temperature experiment platform, a temperature probe is used for measuring the temperature of the pH standard solution and the pH electrode; the upper computer is connected with the pH sensor through an RS485 serial port line;
on the basis of a second temperature experiment platform, carrying out temperature loading and pH loading on a pH sensor according to a preset temperature sequence and a preset pH sequence, acquiring and processing the output temperature and the output pH value through the upper computer to obtain a second output value report, and constructing an electrode temperature compensation model according to the second output value report;
and writing the ADC temperature compensation model and the electrode temperature compensation model into the MCU to complete ADC temperature compensation and electrode temperature compensation of the pH sensor.
Preferably, the constructing the ADC temperature compensation model based on the preset temperature sequence includes:
constructing an ADC temperature compensation model, such as formula (1):
pH(T i )=pH 0 +C 1t T i +C 2t T i 2 (1)
wherein the pH (T) i ) Is the output value T of the pH sensor under the condition of the temperature value measured at the ith time i The temperature value (unit: DEG C) measured by the pH sensor at the ith time; i =1,2,3, …,6, corresponding to 6 temperature gradients respectively;
the ADC temperature compensation model is rewritten into a matrix form as shown in formula (2):
BX=Y (2)
wherein the matrix X is defined as
The matrix Y is defined as
The matrix B is defined as
；
Obtained from the formula (2)
Then, an ADC temperature compensation model is solved; and writing the obtained ADC temperature compensation model into the MCU to complete ADC temperature compensation.
Preferably, the constructing of the electrode temperature compensation model based on the preset temperature sequence and the preset pH sequence includes:
constructing an electrode temperature compensation model as formula (3):
N (i+j-1) (T i ,pH i,j )=N 0 +C 1t T i +C 2t T i 2 +C 1p pH i,j +C 2p pH i,j 2 +C tp T i pH i,j (3)
wherein N is (i+j-1) (T i ,pH i,j ) The output value and pH value of the pH sensor under the conditions of the ith temperature value and the jth pH electrode given pH value i,j The pH value given by the jth pH electrode when the internal temperature value is measured by the pH sensor for the ith time; i =1,2,3, …,6, corresponding to 6 temperature gradients, respectively; j =1,2,3, …,11, corresponding to 11 pH gradients;
rewriting equation (1) to a matrix form, such as equation (4):
AX=Y (4)
wherein the matrix X is defined as
(ii) a The matrix Y is defined as
，
(ii) a The matrix A is defined as
，
Obtained from the formula (4)
Then, an electrode temperature compensation model is solved; and writing the obtained electrode temperature compensation model into the MCU.
Preferably, in the first temperature experiment platform and the second temperature experiment platform, the pH sensor comprises an onboard temperature chip, an ADC, an MCU and a temperature probe; the upper computer is connected with the pH sensor and is used for displaying pH data and temperature data;
the onboard temperature chip, the ADC and the MCU are welded on a circuit board of the pH sensor; and the ADC is used for collecting pH signals and temperature signals and transmitting the pH signals and the temperature signals to the MCU for signal analysis and processing.
Preferably, in the second temperature experiment platform, the temperature probe is used for measuring the temperature of the pH standard solution and the pH electrode;
the upper computer is connected with the pH sensor through an RS485 serial port line.
Preferably, when the ADC temperature compensation model is constructed, the temperature in the preset temperature sequence comprises 6 temperature gradients of 0 ℃,10 ℃,20 ℃,30 ℃,40 ℃ and 50 ℃;
when an electrode temperature compensation model is constructed, the temperature of the preset temperature sequence comprises 6 temperature gradients of 0 ℃,10 ℃,20 ℃,30 ℃,40 ℃ and 50 ℃.
Preferably, when the electrode temperature compensation model is constructed, the pH values of the preset pH sequence comprise 0,1,2,3, …,10, and 11 pH gradients in total.
Preferably, when an ADC temperature compensation model or an electrode temperature compensation model is constructed, the heat of each temperature gradient is preserved for 1 hour, and the temperature rise time of adjacent temperature gradients is 0.5 hour;
each pH gradient was held for 6 minutes while constructing an electrode temperature compensation model.
Compared with the prior art, the invention has the beneficial effects that:
the invention provides a temperature compensation experimental method applied to a pH sensor, and provides an ADC temperature compensation model and an electrode temperature compensation model simultaneously, so that the problems that the aging influence of pH liquid on an electrode, the influence of temperature on the pH value change of the liquid to be detected and the comprehensive influence of temperature on a sensor signal processing circuit are not considered when a plurality of pH sensors carry out temperature compensation in the prior art are solved; the pH sensor can be guaranteed to automatically perform temperature compensation in the changed construction environment temperature, so that the influence of the temperature on the measurement precision is eliminated, and the measurement precision of the pH sensor is further improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the prior art descriptions will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
FIG. 1 is a schematic diagram of the temperature compensation experimental method of the present invention;
FIG. 2 is a comparison of performance before and after temperature compensation under an acidic environment according to the present invention;
FIG. 3 is a comparison of the performance of the present invention before and after temperature compensation in an alkaline environment;
FIG. 4 is a schematic view of the first hour stability test in a field test of the present invention;
FIG. 5 is a schematic view of the stability test at the seventh hour of the field test of the present invention;
FIG. 6 is a schematic view of the eleventh hour stability test in the field test of the present invention;
FIG. 7 is a schematic view of the thirteenth hour stability test in the field test of the present invention.
Detailed Description
The technical solution of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments; all other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1, in a first aspect of the present invention, a temperature compensation experiment method applied to a pH sensor is provided, including:
a pH sensor is placed in a programmable constant temperature box, a pH electrode and a pH standard solution are arranged on one side outside the programmable constant temperature box, and an upper computer is arranged on the other side outside the programmable constant temperature box to construct a first temperature generation experiment platform; wherein, the upper computer is connected with the pH sensor;
on the basis of a first temperature experiment platform, carrying out temperature loading on a pH sensor according to a preset temperature sequence, acquiring and processing output temperature and pH values through an upper computer, obtaining a first output value report, and constructing an ADC temperature compensation model according to the first output value report;
placing a pH sensor, a pH electrode, a temperature probe, a pH standard solution and an MCU (microprogrammed control unit) in the programmable constant temperature box, and connecting the pH sensor with an upper computer outside the programmable constant temperature box to construct a second temperature experiment platform;
on the basis of the second temperature experiment platform, carrying out temperature loading and pH loading on the pH sensor according to a preset temperature sequence and a preset pH sequence, acquiring and processing the output temperature and the output pH value through an upper computer to obtain a second output value report, and constructing an electrode temperature compensation model according to the second output value report;
and writing the ADC temperature compensation model and the electrode temperature compensation model into the MCU to complete ADC temperature compensation and electrode temperature compensation of the pH sensor.
A first temperature experiment platform is set up according to a design scheme: placing an onboard temperature chip, an ADC and an MCU in a pH sensor in a programmable thermostat; the onboard temperature chip is used for measuring the temperature of the pH sensor circuit board, and the onboard temperature chip, the ADC and the MCU are welded on the pH sensor circuit board; the ADC is used for collecting pH signals and temperature signals and then transmitting the pH signals and the temperature signals to the MCU for signal analysis processing.
A temperature probe, a pH electrode and a pH standard liquid are arranged outside the programmable constant temperature box (in order to ensure that the pH electrode and the pH standard liquid are in a constant temperature environment, the voltage signal acquired by the ADC is a constant value); the pH electrode is placed in the pH standard solution to form a primary battery, and the output pH voltage signal is transmitted to an ADC of a pH sensor in the programmable thermostat for collection through a wire.
Then the pH sensor is connected with an upper computer outside the programmable thermostat through an RS485 serial port line; the upper computer is used for displaying a software interface of pH and temperature data; the host computer can output a data report, and the model is conveniently led in.
A second temperature experiment platform is set up according to a design scheme: firstly, a pH electrode, a temperature probe, a pH standard solution and an MCU in a pH sensor are placed in a programmable constant temperature box; the temperature probe is used for measuring the temperature of the pH standard solution and the pH electrode; the ADC is used for collecting a pH signal and a temperature signal and then transmitting the pH signal and the temperature signal to the MCU for signal analysis processing; (since the ADC temperature compensation model carries out temperature compensation on the ADC, the subsequent upper computer does not need to acquire the onboard temperature and only needs to acquire the temperature of the temperature probe); ADC in the pH sensor is welded on the same circuit board through an SPI communication mode and an MCU wire.
A cup of pH standard liquid, a temperature probe and a pH meter with temperature compensation on the market are placed in a programmable thermostat, and the pH meter is introduced to research the change of the pH standard liquid along with the temperature, and the pH values of different points of the temperature gradient are recorded to be conveniently introduced into the standard pH parameters in a pH electrode.
Connecting the pH sensor with an upper computer outside the programmable thermostat through an RS485 serial port line; the upper computer is used for displaying a software interface of pH and temperature data; the host computer can output data report forms, and the model is conveniently led in.
Temperature loading of the pH sensor: setting 6 sections of temperature gradient from 0 ℃,10 ℃,20 ℃ … … to 50 ℃ in a programmable incubator to heat the pH sensor; sequentially collecting output values corresponding to temperature and pH by using an upper computer; and then the output values corresponding to the temperature and the pH are independently averaged, and a first output value report form of the temperature and the pH is derived.
Constructing an ADC temperature compensation model as formula (1):
pH(T i )=pH 0 +C 1t T i +C 2t T i 2 (1)
wherein pH (T) i ) Is the output value T of the pH sensor under the condition of the temperature value measured at the ith time i The temperature value (unit: DEG C) measured by the pH sensor at the ith time; i =1,2,3, …,6 corresponding to 0 ℃,10 ℃,20 ℃,30 ℃,40 ℃,50 ℃,6 temperature gradients respectively,
the ADC temperature compensation model is rewritten into a matrix form as shown in formula (2):
BX=Y (2)
wherein the matrix X is defined as
The matrix Y is defined as
The matrix B is defined as
；
Obtained from the formula (2)
Solving a matrix X and further solving an ADC temperature compensation model; and writing the obtained ADC temperature compensation model into the MCU to complete ADC temperature compensation.
Matrix X, i.e.
The method comprises the steps that a constant term primary term coefficient and a constant term secondary term coefficient in an ADC temperature compensation model are solved to obtain a matrix X, and then the complete ADC temperature compensation model can be obtained.
Temperature and pH loading of the pH sensor: setting 6 sections of temperature gradients of the programmable constant temperature box from 0 ℃,10 ℃,20 ℃, … … and 50 ℃ to heat the pH sensor; simultaneously with pH loading (pH =0, 1,2,3 … …) at each temperature gradient; sequentially collecting output values corresponding to temperature and pH by using an upper computer; and (4) independently averaging the acquired output values of the temperature and the pH value, and deriving a temperature and pH output value report II.
Constructing an electrode temperature compensation model as formula (3):
N (i+j-1) (T i ,pH i,j )=N 0 +C 1t T i +C 2t T i 2 +C 1p pH i,j +C 2p pH i,j 2 +C tp T i pH i,j (3)
wherein N is (i+j-1) (T i ,pH i,j ) The output value and pH value of the pH sensor under the conditions of the ith temperature value and the jth pH electrode given pH value i,j When the internal temperature value is measured for the ith time of the pH sensorThe pH value given by the jth pH electrode; i =1,2,3, …,6, corresponding to 6 temperature gradients, respectively; j =1,2,3, …,11, corresponding to 11 pH gradients; 0 ℃,10 ℃,20 ℃,30 ℃,40 ℃ and 50 ℃; the corresponding pH set point was 0,1,2,3,4,5,6,7,8,9, 10.
Rewriting equation (1) into a matrix form, as equation (4):
AX=Y (4)
wherein the matrix X is defined as
(ii) a The matrix Y is defined as
，
(ii) a The matrix A is defined as
，
Obtained from the formula (4)
Solving a matrix X, and further solving an electrode temperature compensation model; and writing the obtained electrode temperature compensation model into the MCU.
Here matrix X, i.e.
The electrode temperature compensation model comprises a constant term and a coefficient term in the electrode temperature compensation model, and the matrix X is solved for the self-defined coefficient, so that the complete electrode temperature compensation model can be obtained.
It should be noted that the data acquisition frequency of the upper computer is once every 10 s; keeping the temperature of each temperature gradient for 1h, and keeping the temperature rise time of adjacent temperature gradients at 0.5h; each pH gradient was held for 6 minutes.
Referring to fig. 2 to 3, performance tests before and after pH temperature compensation show that after the pH sensor is subjected to ADC temperature compensation and pH electrode temperature compensation, the measurement value of the pH sensor is greatly improved by the temperature, and under the working condition of normal temperature (20 ℃ -30 ℃), the temperature drift value of the pH sensor is small, the temperature drift value in an acidic environment (pH = 4.0) is about 0.003/° c, the temperature drift value in an alkaline environment (pH = 9.18) is about 0.006p ℃, and the temperature drift value of the pH sensor is large when the pH sensor is operated at 0-20 ℃ and 30 ℃ -50 ℃, and the temperature drift value is below 0.01/° c in the general view, which meets the design requirements; in addition, the double-temperature compensation design of the pH sensor ensures that the pH sensor can automatically perform temperature compensation in the changed construction environment temperature, thereby eliminating the influence of temperature on the measurement precision and further improving the measurement precision of the pH sensor.
Referring to fig. 4 to 7, the temperature and the PH value measured by the PH sensor in the first hour, the seventh hour, the eleventh hour and the thirteenth hour are selected, so that the stability of the test data of the PH sensor during long-time working and ultra-long-time running can be effectively reflected when the PH sensor starts to measure, the change orientation of the PH value is approximately 6.60 to 6.62 within four hours, and the data jitter amplitude is only about 0.17% of the full-scale range, which proves that the stability of the PH sensor during measuring the data meets the performance requirement.
Part of data in the formula is obtained by removing dimension and taking the value to calculate, and the formula is obtained by simulating a large amount of collected data through software and is closest to a real situation; the preset parameters and the preset threshold values in the formula are set by those skilled in the art according to actual conditions or obtained through simulation of a large amount of data.
Although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the spirit and scope of the present invention.
Claims (5)
1. The temperature compensation experiment method applied to the pH sensor is characterized by comprising the following steps:
placing an onboard temperature chip, an ADC (analog to digital converter) and an MCU (microprogrammed control unit) of a pH sensor in a programmable incubator, arranging a temperature probe and a pH electrode of the pH sensor at one side outside the programmable incubator, wherein the pH electrode is used for measuring a pH standard solution; the upper computer is arranged on the other side outside the programmable constant temperature box, and a first generated temperature experiment platform is constructed; wherein, the upper computer is connected with the pH sensor; the onboard temperature chip, the ADC and the MCU are welded on the pH sensor circuit board, and the onboard temperature chip is used for measuring the temperature of the pH sensor circuit board;
on the basis of a first temperature experiment platform, carrying out temperature loading on a pH sensor according to a preset temperature sequence, acquiring and processing an output temperature and a pH value through an upper computer, obtaining a first output value report, and constructing an ADC temperature compensation model according to the first output value report;
placing a pH electrode, a temperature probe, a pH standard solution and an MCU of a pH sensor in the programmable incubator, and connecting the pH sensor with an upper computer outside the programmable incubator to construct a second temperature experiment platform; in the second temperature experiment platform, a temperature probe is used for measuring the temperature of the pH standard solution and the pH electrode; the upper computer is connected with the pH sensor through an RS485 serial port line;
on the basis of a second temperature experiment platform, carrying out temperature loading and pH loading on a pH sensor according to a preset temperature sequence and a preset pH sequence, acquiring and processing the output temperature and the output pH value through the upper computer to obtain a second output value report, and constructing an electrode temperature compensation model according to the second output value report;
writing the ADC temperature compensation model and the electrode temperature compensation model into the MCU to complete ADC temperature compensation and electrode temperature compensation of the pH sensor;
an ADC temperature compensation model is built based on a preset temperature sequence, and the method comprises the following steps:
constructing an ADC temperature compensation model as formula (1):
pH(T i )=pH 0 +C 1t T i +C 2t T i 2 (1)
wherein the pH (T) i ) Is the output value T of the pH sensor under the condition of the temperature value measured at the ith time i The temperature value measured by the pH sensor at the ith time; i =1,2,3, …,6, with the unit of ° c, corresponding to 6 temperature gradients, respectively;
the ADC temperature compensation model is rewritten into a matrix form as shown in formula (2):
BX=Y (2)
wherein the matrix X is defined as
The matrix Y is defined as
The matrix B is defined as
；
Obtained from the formula (2)
Solving out a matrix
Then, an ADC temperature compensation model is solved; writing the obtained ADC temperature compensation model into the MCU to complete ADC temperature compensation;
an electrode temperature compensation model is constructed based on a preset temperature sequence and a preset pH sequence, and the method comprises the following steps:
constructing an electrode temperature compensation model, such as formula (3):
N (i+j-1) (T i ,pH i,j )=N 0 +C 1t T i +C 2t T i 2 +C 1p pH i,j +C 2p pH i,j 2 +C tp T i pH i,j (3)
wherein, N (i+j-1) (T i ,pH i,j ) The output value and pH value of the pH sensor under the conditions of the ith temperature value and the jth pH electrode given pH value i,j For pH sensingThe pH value given by the pH electrode at the jth time is measured when the temperature value of the inside of the device is measured at the ith time; i =1,2,3, …,6, corresponding to 6 temperature gradients, respectively; j =1,2,3, …,11, corresponding to 11 pH gradients;
rewriting equation (1) into a matrix form, as equation (4):
AX=Y (4)
wherein the matrix X is defined as
(ii) a The matrix Y is defined as
，
(ii) a The matrix A is defined as
，
(ii) a Wherein the matrix A is a coefficient matrix with AX = Y;
obtained from the formula (4)
To obtain a parameter vector
Further solving an electrode temperature compensation model; and writing the obtained electrode temperature compensation model into the MCU.
2. The temperature compensation experiment method applied to the pH sensor according to claim 1, wherein the pH sensor comprises an onboard temperature chip, an ADC, an MCU and a temperature probe; the upper computer is connected with the pH sensor and is used for displaying pH data and temperature data;
the onboard temperature chip, the ADC and the MCU are welded on a circuit board of the pH sensor; and the ADC is used for collecting pH signals and temperature signals and transmitting the pH signals and the temperature signals to the MCU for signal analysis and processing.
3. The temperature compensation experimental method applied to the pH sensor according to claim 1, wherein the temperatures in the preset temperature sequence include 6 temperature gradients of 0 ℃,10 ℃,20 ℃,30 ℃,40 ℃ and 50 ℃ when the ADC temperature compensation model is constructed;
when an electrode temperature compensation model is constructed, the temperature of the preset temperature sequence comprises 6 temperature gradients of 0 ℃,10 ℃,20 ℃,30 ℃,40 ℃ and 50 ℃.
4. The temperature-compensated experimental method applied to the pH sensor as claimed in claim 1, wherein the pH value of the preset pH sequence comprises 11 pH gradients of 0,1,2,3, … and 10.
5. The temperature compensation experiment method applied to the pH sensor according to claim 1, wherein when an ADC temperature compensation model or an electrode temperature compensation model is constructed, the temperature of each temperature gradient is kept for 1 hour, and the temperature rise time of adjacent temperature gradients is 0.5 hour;
each pH gradient was held for 6 minutes while constructing an electrode temperature compensation model.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211102674.3A CN115184427B (en) | 2022-09-09 | 2022-09-09 | Temperature compensation experiment method applied to pH sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211102674.3A CN115184427B (en) | 2022-09-09 | 2022-09-09 | Temperature compensation experiment method applied to pH sensor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115184427A CN115184427A (en) | 2022-10-14 |
| CN115184427B true CN115184427B (en) | 2022-12-13 |
Family
ID=83524727
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211102674.3A Active CN115184427B (en) | 2022-09-09 | 2022-09-09 | Temperature compensation experiment method applied to pH sensor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115184427B (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113932765A (en) * | 2021-10-28 | 2022-01-14 | 中大检测(湖南)股份有限公司 | High-precision static level gauge based on temperature compensation and temperature compensation method thereof |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58160859A (en) * | 1982-03-18 | 1983-09-24 | Horiba Ltd | Ph meter |
| US5016201A (en) * | 1989-02-06 | 1991-05-14 | Bryan Avron I | System for calibrating, monitoring and reporting the status of a pH sensor |
| CN102866180B (en) * | 2012-09-19 | 2014-06-25 | 河海大学 | High-precision intelligent acidity meter and measuring method thereof |
| CN203720130U (en) * | 2014-02-28 | 2014-07-16 | 金川集团股份有限公司 | PH value measuring device |
| CN206399476U (en) * | 2016-12-26 | 2017-08-11 | 东莞市海川博通信息科技有限公司 | A kind of water analysis circuit |
| CN111157681A (en) * | 2019-12-31 | 2020-05-15 | 陕西中良智能科技有限公司 | Automatic liquid ph value adjusting system and method |
| CN214703410U (en) * | 2021-01-19 | 2021-11-12 | 中国科学院过程工程研究所 | Online pH detection device |
| CN216594905U (en) * | 2021-11-18 | 2022-05-24 | 常州罗盘星检测科技有限公司 | Online multi-parameter water quality measuring sensor |
-
2022
- 2022-09-09 CN CN202211102674.3A patent/CN115184427B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113932765A (en) * | 2021-10-28 | 2022-01-14 | 中大检测(湖南)股份有限公司 | High-precision static level gauge based on temperature compensation and temperature compensation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115184427A (en) | 2022-10-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110196075B (en) | Remote temperature and humidity testing method for environmental test equipment calibration | |
| CN110018275A (en) | A kind of gas detector with compensation function and compensation method | |
| CN101782567B (en) | Intelligent ammonia nitrogen transmitting system and ammonia nitrogen in situ high-frequency detection method | |
| CN105976411B (en) | A kind of preposition measurement module and Calibration Method for electrical impedance tomography data collecting system | |
| CN106405460A (en) | Electronic instrument voltage detection calibration system and calibration method | |
| CN205664929U (en) | Level sensor automatic correcting device vows in pond | |
| CN115791891A (en) | Structural damage identification method and system based on piezoelectric impedance technology | |
| CN206114150U (en) | Measure thermocouple time constant's device | |
| CN105738438A (en) | Instrument and method for fast detecting bicarbonate radical and carbonate radical in water through double-electrode method | |
| CN115184427B (en) | Temperature compensation experiment method applied to pH sensor | |
| CN112083299B (en) | DC system insulation fault prediction method based on Kalman filtering | |
| CN115200748B (en) | State measurement control system based on intelligent electronic thermometer | |
| CN109357793B (en) | Pressure measurement system and method based on voltage type pressure sensor | |
| CN107543574B (en) | Automatic detector for high-temperature aging test of airborne sensor and operation method | |
| CN212391150U (en) | Temperature sensor precision test system | |
| CN209690255U (en) | A kind of Multiple Source Sensor calibration platform | |
| CN113049650A (en) | Intelligent calibration system and method for soil humidity sensor | |
| CN113552529A (en) | Self-calibration system and method based on intelligent electric energy meter online monitoring | |
| CN110285895A (en) | A kind of acquisition of temperature measurement utensil data and detection device and detection method | |
| CN205562066U (en) | A measuring circuit for PT1000 temperature sensor | |
| Wen et al. | Research on the Compliance Judgment of Indication Error of Calibration Result of Platinum Resistance Air Temperature Sensor | |
| CN217980580U (en) | Wearable electronic thermometer based on disposable temperature probe | |
| CN103616082A (en) | Intelligent miniature temperature recorder | |
| CN203643391U (en) | Self-adaption ion meter | |
| CN204241406U (en) | A kind of SCM Based solution ph measuring instrument |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |