Piezoresistor pressure gauge measuring system based on temperature compensation

Abstract

The invention relates to the field of pressure measurement, in particular to a piezoresistor pressure gauge measuring system based on temperature compensation, and aims to solve the problems that the applicable temperature range of a pressure gauge is small and a pressure gauge temperature compensation system is difficult to comprehensively detect and evaluate due to the fact that temperature compensation of the pressure gauge at different temperatures is different when the pressure gauge is used. Comprising a pressure providing module, a pressure measuring unit, a compensation collecting unit and a data checking unit. Standard pressure is provided for the pressure gauge through the stable pressure providing module, measurement is carried out according to the pressure gauge, a direct measurement result and a temperature compensation result are obtained, the direct measurement result, the temperature compensation result and the standard pressure are subjected to comprehensive comparative analysis, and the measurement accuracy is improved. Therefore, the temperature compensation accuracy of the pressure gauge is comprehensively analyzed, and the measurement accuracy of the pressure gauge is improved.

Description

Technical Field

[0001] The invention relates to the field of pressure measurement, in particular to a varistor pressure gauge measurement system based on temperature compensation. Background Art

[0002] Pressure instruments are widely used in various industries as conventional instruments for measuring pressure. At present, there are two main types of products for measuring pressure in industry. One type is a mechanical pressure gauge, which transmits the pressure deformation to the pointer through the elastic deformation of the sensitive element in the gauge, and then causes the pointer to rotate to display the pressure. The other type is a pressure transmitter that outputs industrial standard signals, which transmits the monitored pressure in the form of electrical signals through the cooperation of the pressure sensor and the transmitter circuit board inside.

[0003] A considerable part of pressure sensors are measured by varistors. When the material is subjected to different pressures, its own electrical properties, such as resistance value, will change, thereby achieving different current outputs, and then converting pressure signals into electrical signals. In actual use, the electrical properties of varistors are also significantly affected by temperature, so that the pressure value measured by the varistor during the application process is affected by temperature and offset. Therefore, in order to ensure the accuracy of the pressure gauge, the pressure gauge needs to be temperature compensated;

[0004] At present, the temperature compensation system of the pressure gauge in the prior art still has some shortcomings. The existing temperature compensation is generally calibrated before leaving the factory, so as to preset the temperature compensation ratio of the pressure gauge. However, in actual application, the temperature of the environment in which the pressure gauge is located is constantly changing. Therefore, there is a certain error in adopting a unified compensation ratio. At the same time, during the long-term operation of the pressure gauge, its own electrical performance will also have a certain deviation, which will lead to inaccurate measurement results of the pressure gauge. After the pressure gauge measures inaccurately, it is difficult to determine whether the inaccuracy of the pressure gauge is caused by insufficient temperature compensation or inaccurate pressure measurement, which is not conducive to the rapid inspection and maintenance of the pressure gauge.

[0005] In view of the above technical problems, this application proposes a solution. Summary of the invention

[0006] The present invention provides a standard pressure for a pressure gauge through a stable pressure providing module, and performs measurements according to the pressure gauge to obtain results obtained by direct measurement and results after temperature compensation. The direct measurement results, the temperature compensation results and the standard pressure are comprehensively compared and analyzed to obtain measurement results of multiple aspects of the pressure gauge, such as the initial deviation, compensation deviation and compensation coupling. Thus, a comprehensive analysis is performed on the temperature compensation accuracy of the pressure gauge, the measurement accuracy of the pressure gauge is improved, and the problems that the temperature compensation of the pressure gauge at different temperatures when in use has a gap, resulting in a small applicable temperature range of the pressure gauge and that it is difficult to conduct a comprehensive detection and evaluation of the temperature compensation system of the pressure gauge are solved. A varistor pressure gauge measurement system based on temperature compensation is proposed.

[0007] The purpose of the present invention can be achieved through the following technical solutions:

[0008] A temperature-compensated varistor pressure gauge measurement system includes a pressure providing module, which is used to provide a set value of pressure to the pressure gauge, record it as the standard pressure, and record the change of the standard pressure, and send the standard pressure and its change to a data checking unit;

[0009] A pressure measuring unit, wherein the pressure measuring unit can collect the pressure provided by the pressure providing module through the pressure gauge to obtain an initial collected pressure, and send the initial collected pressure to the data checking unit;

[0010] A compensation collection unit, which continuously collects the temperature change of the pressure gauge and sends the collected temperature change to the pressure measurement unit. The pressure measurement unit performs compensation calculation according to the temperature change to obtain the compensated pressure, and sends the compensated pressure to the data verification unit;

[0011] A data checking unit performs a comprehensive analysis on the standard pressure, the initial acquisition pressure and the compensated pressure to obtain an initial deviation value, a compensated deviation value and a compensation coupling degree, and generates a measurement result.

[0012] As a preferred embodiment of the present invention, the pressure providing module includes a change recording unit and a pressure guarantee unit, the pressure guarantee unit is used to provide the standard pressure to the pressure gauge according to the set control logic, wherein the set control logic of the standard pressure includes the pressure value and the pressure maintenance time, and the change recording unit records the pressure value and the pressure value change provided by the pressure guarantee unit;

[0013] The method for recording the pressure value change by the change recording unit is:

[0014] The change recording unit creates a time axis, and records the pressure values ​​at different times on the time axis according to their corresponding times, thereby obtaining a standard pressure curve.

[0015] As a preferred embodiment of the present invention, when collecting pressure, the pressure measurement unit simultaneously records the collected pressure and the time of the pressure, creates an initial collected pressure curve according to the recorded information, and sends the initial collected pressure curve to the data checking unit;

[0016] The pressure measurement unit divides the initial collected pressure curve into a pulse segment and a change segment, wherein the pulse segment is the portion of the initial collected pressure curve where the pressure remains constant, and the change segment is the pressure variation region between two groups of pulse segments in the initial collected pressure curve.

[0017] As a preferred embodiment of the present invention, after collecting the temperature change of the pressure gauge, the compensation acquisition unit records the temperature change of the pressure gauge in a time axis manner, and obtains a temperature change curve according to the recorded results;

[0018] The compensation acquisition unit obtains the temperature compensation coefficient of the varistor and obtains the initial acquisition pressure curve through the pressure measurement unit. The compensation acquisition unit corrects the initial acquisition pressure curve through the temperature compensation coefficient and the temperature change curve to obtain the compensated pressure curve.

[0019] As a preferred embodiment of the present invention, the method for the compensation acquisition unit to correct the initial acquisition pressure curve is:

[0020] Step 1: Extract the pressure Pi and time ti corresponding to point i on the initial acquisition pressure curve, where i is a non-zero natural number;

[0021] Step 2: Obtain the temperature Ti corresponding to the time ti on the temperature change curve according to the time ti;

[0022] Step 3: Generate the compensated pressure through formula analysis using the temperature compensation coefficient, temperature Ti and pressure Pi;

[0023] Step 4: Create a time axis, and record the compensated pressure obtained on the time axis according to time ti to obtain a compensated pressure curve.

[0024] As a preferred embodiment of the present invention, the data verification unit compares the standard pressure curve and the compensated pressure curve by overlapping, obtains the difference between the compensated pressure curve and the standard pressure curve corresponding to each time point based on the comparison, records it as the compensation deviation value, and compares the compensation deviation value with the set threshold value, and classifies the compensation deviation value into a normal deviation value and an excessive deviation value based on the comparison result.

[0025] As a preferred embodiment of the present invention, the data checking unit compares the initial collected pressure curve with the standard pressure curve to obtain the difference between the initial collected pressure curve and the standard pressure curve at the same time, and records it as the initial error value. The data checking unit obtains the temperature at the corresponding time through the temperature change curve, and records the initial error value and the temperature at the corresponding time point as a set of related data;

[0026] The data checking unit calculates the ratio of the initial error value and the temperature in the same group of associated data to obtain an initial deviation value, and compares the initial deviation value with a set deviation threshold value, and obtains a deviation qualified signal or a deviation unqualified signal according to the comparison result.

[0027] As a preferred embodiment of the present invention, the data verification unit obtains the pulse segment and the change segment in the initial acquisition pressure curve through the pressure measurement unit, and records the calculated compensation deviation value in the initial acquisition pressure curve according to the corresponding time, and simultaneously calculates the excess deviation value in the pulse segment and the excess deviation value in the change segment to obtain the pulse coupling ratio and the change coupling ratio, and compares the pulse coupling ratio and the change coupling ratio with the ratio threshold value respectively, and generates a coupling qualified signal or a coupling unqualified signal according to the comparison result.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. In the present invention, when a varistor pressure gauge is used for measurement, a stable pressure providing module is used to provide a standard pressure for the pressure gauge, and measurement is performed according to the pressure gauge to obtain a direct measurement result and a temperature-compensated result. A comprehensive comparative analysis is performed on the direct measurement result, the temperature-compensated result and the standard pressure to obtain measurement results of the initial deviation, compensation deviation and compensation coupling of the pressure gauge, thereby performing a comprehensive analysis on the temperature compensation accuracy of the pressure gauge and improving the measurement accuracy of the pressure gauge.

[0030] 2. In the present invention, when measuring the pressure gauge of the varistor, the actually measured pressure and temperature compensation are calculated to obtain the correction of the pressure, and then the deviation of the compensation result is obtained based on the difference between the temperature correction and the provided standard pressure, so as to make a preliminary judgment on the accuracy of the compensation result, and then the coupling of the temperature compensation of the pressure gauge when the external pressure is constantly changing is judged based on the distribution of accurate examples and inaccurate examples of the compensation result under pressure changes. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0032] Figure 1is a system block diagram of the present invention;

[0033] Figure 2 It is a system flow chart of the present invention. DETAILED DESCRIPTION

[0034] The technical scheme of the present invention will be described clearly and completely in conjunction with the embodiments below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] Embodiment 1:

[0036] See also Figure 1 - Figure 2 As shown, a varistor pressure gauge measurement system based on temperature compensation includes a pressure providing module, a pressure measuring unit, a compensation acquisition unit and a data checking unit;

[0037] The pressure providing module includes a change recording unit and a pressure guarantee unit. The pressure guarantee unit is used to provide the standard pressure to the pressure gauge according to the set control logic, wherein the set control logic of the standard pressure includes the pressure value and the pressure maintenance time. The change recording unit records the pressure value and the pressure value change provided by the pressure guarantee unit.

[0038] The method for the change recording unit to record the change of pressure value is:

[0039] The change recording unit creates a time axis, records the pressure values ​​at different times on the time axis according to their corresponding times, thereby obtaining a standard pressure curve, and sends the standard pressure curve to the data checking unit;

[0040] The pressure measuring unit can collect the pressure provided by the pressure providing module through the pressure gauge. When collecting the pressure, the pressure measuring unit simultaneously records the collected pressure and the time of the pressure, creates an initial collected pressure curve according to the recorded information, and sends the initial collected pressure curve to the data checking unit;

[0041] The pressure measurement unit divides the initial collected pressure curve into a pulse segment and a change segment, wherein the pulse segment is the portion of the initial collected pressure curve where the pressure remains constant, and the change segment is the pressure change region between two groups of pulse segments in the initial collected pressure curve;

[0042] The compensation acquisition unit continuously acquires the temperature change of the pressure gauge, and after acquiring the temperature change of the pressure gauge, records the temperature change of the pressure gauge in the form of a time axis, and obtains a temperature change curve according to the recorded results. The compensation acquisition unit extracts the pressure Pi and time ti corresponding to point i on the initial acquisition pressure curve, where i is a non-zero natural number. The compensation acquisition unit obtains the temperature Ti corresponding to time ti on the temperature change curve according to time ti. The compensation acquisition unit uses the temperature compensation coefficient, temperature Ti and pressure Pi through the formula Generate the compensated pressure Bi, where q is the temperature compensation coefficient. The compensation acquisition unit then creates a time axis, records the obtained compensated pressure on the time axis according to time ti, obtains the compensated pressure curve, and sends the compensated pressure to the data verification unit.

[0043] Embodiment 2:

[0044] See also Figure 1 - Figure 2 As shown, the data checking unit performs a comprehensive analysis on the standard pressure, the initial acquisition pressure and the compensated pressure, obtains the initial deviation value, the compensated deviation value and the compensation coupling degree, and generates a measurement result;

[0045] Among them, the analysis method of compensation deviation value and compensation coupling degree is:

[0046] The data checking unit compares the standard pressure curve with the compensated pressure curve, obtains the difference between the compensated pressure curve and the standard pressure curve corresponding to each time point according to the comparison, records it as the compensation deviation value, and compares the compensation deviation value with the set threshold value. If the compensation deviation value is greater than the set threshold value, the compensation deviation value is classified as an excessive deviation value; if the compensation deviation value is less than or equal to the set threshold value, the compensation deviation value is classified as a normal deviation value;

[0047] The data checking unit obtains the pulse segment and the change segment in the initial acquisition pressure curve through the pressure measuring unit, and records the calculated compensation deviation value in the initial acquisition pressure curve according to the corresponding time, and simultaneously calculates the over-standard deviation value in the pulse segment and the over-standard deviation value in the change segment to obtain the pulse coupling ratio and the change coupling ratio, and compares the pulse coupling ratio and the change coupling ratio with the ratio threshold value respectively. If the pulse coupling ratio is greater than the ratio threshold value, a pulse coupling unqualified signal is generated, and if the pulse coupling ratio is not greater than the ratio threshold value, a pulse coupling qualified signal is generated;

[0048] If the change coupling ratio is greater than the ratio threshold, a change coupling failure signal is generated; if the change coupling ratio is not greater than the ratio threshold, a change coupling qualification signal is generated;

[0049] When the data checking unit generates a pulse coupling qualified signal and a change coupling qualified signal at the same time, it is judged that the compensation coupling degree meets the standard;

[0050] When the data checking unit generates any one of a pulse coupling failure signal and a change coupling failure signal, it is determined that the compensation coupling degree does not meet the standard.

[0051] Among them, the analysis method of the initial deviation value is:

[0052] The data checking unit compares the initial collected pressure curve with the standard pressure curve, obtains the difference between the initial collected pressure curve and the standard pressure curve at the same time, and records it as the initial error value. The data checking unit obtains the temperature at the corresponding time through the temperature change curve, and records the initial error value and the temperature at the corresponding time point as a set of related data;

[0053] The data verification unit calculates the ratio of the initial error value and temperature in the same group of related data to obtain the initial deviation value, and compares the initial deviation value with the set deviation threshold. If the initial deviation value is greater than the set deviation threshold, a deviation failure signal is generated. If the initial deviation value is less than or equal to the set deviation threshold, a deviation acceptance signal is generated. The data verification unit sends the deviation acceptance signal and the deviation failure signal to the management platform through the network for display, so as to monitor the temperature influence ratio of the varistor of the pressure gauge.

[0054] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A varistor pressure gauge measurement system based on temperature compensation, characterized in that: It includes a pressure providing module, which is used to provide a set value of pressure to the pressure gauge, record it as the standard pressure, and record the change of the standard pressure, and send the standard pressure and its change to the data checking unit; A pressure measuring unit, wherein the pressure measuring unit can collect the pressure provided by the pressure providing module through the pressure gauge to obtain an initial collected pressure, and send the initial collected pressure to the data checking unit; A compensation collection unit, which continuously collects the temperature change of the pressure gauge and sends the collected temperature change to the pressure measurement unit. The pressure measurement unit performs compensation calculation according to the temperature change to obtain the compensated pressure, and sends the compensated pressure to the data verification unit; A data checking unit performs a comprehensive analysis on the standard pressure, the initial acquisition pressure and the compensated pressure to obtain an initial deviation value, a compensated deviation value and a compensation coupling degree, and generates a measurement result.

2. The temperature-compensated varistor pressure gauge measurement system according to claim 1, characterized in that: The pressure providing module includes a change recording unit and a pressure guarantee unit. The pressure guarantee unit is used to provide a standard pressure to the pressure gauge according to a set control logic, wherein the set control logic of the standard pressure includes a pressure value and a pressure maintenance time. The change recording unit records the pressure value and the pressure value change provided by the pressure guarantee unit. The method for recording the pressure value change by the change recording unit is: The change recording unit creates a time axis, and records the pressure values ​​at different times on the time axis according to their corresponding times, thereby obtaining a standard pressure curve.

3. The temperature-compensated varistor pressure gauge measurement system according to claim 1, characterized in that: When the pressure measurement unit collects the pressure, the collected pressure and the time of the pressure are recorded simultaneously, an initial collected pressure curve is created according to the recorded information, and the initial collected pressure curve is sent to the data checking unit; The pressure measurement unit divides the initial collected pressure curve into a pulse segment and a change segment, wherein the pulse segment is the portion of the initial collected pressure curve where the pressure remains constant, and the change segment is the pressure variation region between two groups of pulse segments in the initial collected pressure curve.

4. The temperature-compensated varistor pressure gauge measurement system according to claim 1, characterized in that: After collecting the temperature change of the pressure gauge, the compensation acquisition unit records the temperature change of the pressure gauge in a time axis manner, and obtains a temperature change curve according to the recorded results; The compensation acquisition unit obtains the temperature compensation coefficient of the varistor and obtains the initial acquisition pressure curve through the pressure measurement unit. The compensation acquisition unit corrects the initial acquisition pressure curve through the temperature compensation coefficient and the temperature change curve to obtain the compensated pressure curve.

5. The temperature-compensated varistor pressure gauge measurement system according to claim 4, characterized in that: The method for the compensation acquisition unit to correct the initial acquisition pressure curve is: Step 1: Extract the pressure Pi and time ti corresponding to point i on the initial acquisition pressure curve, where i is a non-zero natural number; Step 2: Obtain the temperature Ti corresponding to the time ti on the temperature change curve according to the time ti; Step 3: Generate the compensated pressure through formula analysis using the temperature compensation coefficient, temperature Ti and pressure Pi; Step 4: Create a time axis, and record the compensated pressure obtained on the time axis according to time ti to obtain a compensated pressure curve.

6. The temperature-compensated varistor pressure gauge measurement system according to claim 1, characterized in that: The data checking unit compares the standard pressure curve and the compensated pressure curve by overlapping, obtains the difference between the compensated pressure curve and the standard pressure curve corresponding to each time point based on the comparison, records it as the compensation deviation value, and compares the compensation deviation value with the set threshold value, and classifies the compensation deviation value into a normal deviation value and an excessive deviation value based on the comparison result.

7. The temperature-compensated varistor pressure gauge measurement system according to claim 1, characterized in that: The data checking unit compares the initial collected pressure curve with the standard pressure curve to obtain the difference between the initial collected pressure curve and the standard pressure curve at the same time, and records it as the initial error value. The data checking unit obtains the temperature at the corresponding time through the temperature change curve, and records the initial error value and the temperature at the corresponding time point as a set of related data; The data checking unit calculates the ratio of the initial error value and the temperature in the same group of associated data to obtain an initial deviation value, and compares the initial deviation value with a set deviation threshold value, and obtains a deviation qualified signal or a deviation unqualified signal according to the comparison result.

8. The temperature-compensated varistor pressure gauge measurement system according to claim 1, characterized in that: The data checking unit obtains the pulse segment and the change segment in the initial acquisition pressure curve through the pressure measuring unit, and records the calculated compensation deviation value in the initial acquisition pressure curve according to the corresponding time, and simultaneously calculates the excess deviation value in the pulse segment and the excess deviation value in the change segment to obtain the pulse coupling ratio and the change coupling ratio, and compares the pulse coupling ratio and the change coupling ratio with the ratio threshold value respectively, and generates a coupling qualified signal or a coupling unqualified signal according to the comparison result.

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