Ultrasonic water meter flow temperature compensation method, medium and terminal

Abstract

The invention is suitable for the technical field of ultrasonic water meters, and relates to an ultrasonic water meter flow temperature compensation method, a medium and a terminal.The method comprises the steps that S10, errors of all flow points of an ultrasonic water meter at a certain temperature t DEG C within the normal temperature range are measured; s20, the temperature t DEG C serves as the standard, errors of all flow points of the ultrasonic water meter at (t + 3 * k) DEG C are measured, and k is an integer; s30, based on the error of each flow point at the temperature t DEG C, performing piecewise fitting linear correction; s40, performing piecewise fitting linear correction on the basis of the error of each flow point at (t + 3 * k) DEG C; and S50, adopting a Lagrange interpolation method to determine segmentation fitting formulas of other temperature ranges. The flow compensation method is simple in process, convenient to operate and capable of compensating flow at different temperatures so as to ensure that all flow points can meet the precision requirement within the whole temperature range.

Description

Technical Field

[0001] The invention belongs to the technical field of ultrasonic water meters, and in particular relates to an ultrasonic water meter flow temperature compensation method, medium and terminal. Background Art

[0002] Ultrasonic water meters are developing rapidly in the water meter market due to their high measurement accuracy, high reliability, wide range ratio, and long service life. At present, the biggest problem with ultrasonic water meters is that temperature has a great influence on them. In the existing technology, fixed formula temperature correction is used to make accurate compensation for flow at different temperatures, and it is impossible to ensure that all flow points can meet the accuracy requirements within the entire temperature range.

[0003] The patent with the announcement number CN113607245B provides an adaptive flow compensation method for ultrasonic water meters, including the following steps: Step 1: Data collection: Collect temperature point T, flow rate point V, and pressure point P, collect the temperature point T through the temperature sensor at the inlet and outlet of the pipe section, determine the flow rate point V through the electromagnetic flowmeter of the calibration station, collect the pressure point P through the built-in pressure sensor of the calibration station, and use the ultrasonic water meter time chip to collect the upstream flight time and downstream flight time of the ultrasonic transducer corresponding to each sampling point; Step 2: Estimated flow value calculation; Step 3: Actual flow compensation parameter calculation; Step 4: Obtain the optimal adaptive compensation parameter equation; Step 5: Calculate the optimal adaptive flow compensation parameter: According to the optimal adaptive compensation parameter equation obtained in step 4 and the current temperature value T, flow rate value V, and pressure value P, calculate the optimal adaptive flow compensation parameter. Although the optimal adaptive flow compensation parameter is adaptively obtained under different environmental conditions in this patent, it does not record the technical solution for compensating the flow in the entire temperature range, which has the same disadvantages as the prior art.

[0004] Therefore, how to provide an ultrasonic water meter flow temperature compensation method that can compensate for flow at different temperatures to ensure that all flow points within the entire temperature range can meet the accuracy requirements is an urgent problem to be solved by personnel in this technical field. Summary of the invention

[0005] In view of the deficiencies in the prior art, the purpose of the present invention is to provide an ultrasonic water meter flow temperature compensation method to solve the problem that the existing ultrasonic water meter cannot accurately compensate the flow at different temperatures and cannot ensure that all flow points in the entire temperature range can meet the accuracy requirements; in addition, the present invention also provides an ultrasonic water meter flow temperature compensation medium and terminal.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a method for flow temperature compensation of an ultrasonic water meter, comprising the following steps:

[0008] S10, measure the error of each flow point of the ultrasonic water meter at a certain temperature t℃ within the normal temperature range; S20, take the temperature t℃ as the reference, measure the error of each flow point of the ultrasonic water meter at (t+3*k)℃, k is an integer;

[0009] S30. Based on the error of each flow point at temperature t℃, perform piecewise fitting linear correction; S40. Based on the error of each flow point at (t+3*k)℃, perform piecewise fitting linear correction; S50. Use Lagrange interpolation method to determine the piecewise fitting formula for other temperature ranges.

[0010] Furthermore, if at the instantaneous flow rate q, the water flow of the standard meter is V, the water flow of the meter under test is Vp, and Qp is the instantaneous flow rate of the meter under test, then the error expression is as follows:

[0011] K = (Vp-V) / V;

[0012] The average error of n times is:

[0013] Kp=(K1+K2+K3+……+K n ) / n;

[0014] Where n≥3, and Qp / q=Vp / V;

[0015] The average instantaneous flow expression of the inspected meter is as follows:

[0016] Qp=(1+Kp )*q.

[0017] Furthermore, in step S30, assuming that the entire flow segment is divided into two segments, then:

[0018] q t01 =k t01 *Qp+b t01 , 1.1*Q4>Qp≥a;

[0019] q t02 =k t02 *Qp+b t02 , a>Qp≥Q1;

[0020] where q t01、 q t02 is the corrected flow rate, and the error with the standard instantaneous flow rate q is no more than 1%, and a is the segmentation point.

[0021] Furthermore, in step S40, the segmented point a at room temperature is used for segmented fitting linear correction. When k=1, that is, when the temperature is (t+3)°C, the error fitting formula is as follows:

[0022] q t11 =k t11 *Qp+b t11 ;

[0023] q t12 =k t12 *Qp+b t12 ;

[0024] Among them, q t11 ,q t12 It is the corrected flow rate, and the error with the standard instantaneous flow rate q is no more than 1.5%.

[0025] Furthermore, in step S50, when the actual temperature T is between t°C and (t+3)°C, the Lagrange interpolation method is used to obtain:

[0026]

[0027] Then the coefficient of the piecewise correction fitting formula at T℃ is:

[0028]

[0029]

[0030] Furthermore, the piecewise fitting formula at temperature T°C is:

[0031]

[0032] Furthermore, in step S10, the normal temperature range is 20±5° C., and the number of flow points is not less than 20.

[0033] Furthermore, in step S20, 0≤t+3*k≤50.

[0034] In a second aspect, the present invention further provides a computer-readable storage medium, wherein the storage medium stores a computer program, and the computer program implements the above method when executed by a processor.

[0035] In a third aspect, the present invention further provides an electronic terminal, comprising: a processor and a memory; the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory, so that the terminal executes the method as described above.

[0036] Compared with the prior art, the ultrasonic water meter flow temperature compensation method, medium and terminal provided by the present invention have at least the following beneficial effects:

[0037] The biggest problem of ultrasonic water meters at present is that temperature has a great influence on them. In the prior art, fixed formula temperature correction is applied to them, which cannot accurately compensate for the flow at different temperatures, and cannot ensure that all flow points can meet the accuracy requirements in the entire temperature range. The present invention has a simple process and convenient operation. It takes the flow point at room temperature as the benchmark, which is convenient for production calibration and meter inspection. It uses the measured error coefficient of each flow point at each temperature for compensation. The ultrasonic pipe section and transducer under the same mold have universal applicability, which can ensure that after compensation, the accuracy requirements can be met in the full temperature and full flow range. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the scheme of the present invention, a brief introduction is given below to the figures required for use in the description of the embodiments. Obviously, the figures described below are some embodiments of the present invention. For ordinary technicians in this field, other figures can be obtained based on these figures without paying any creative work.

[0039] Figure 1 The present invention provides a flow chart of an ultrasonic water meter flow temperature compensation method. DETAILED DESCRIPTION

[0040] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0042] The present invention provides an ultrasonic water meter flow temperature compensation method, which is applied to the temperature compensation process of the ultrasonic water meter. The ultrasonic water meter flow temperature compensation method comprises the following steps:

[0043] S10, measure the error of each flow point of the ultrasonic water meter at a certain temperature t℃ within the normal temperature range; S20, take the temperature t℃ as the reference, measure the error of each flow point of the ultrasonic water meter at (t+3*k)℃, k is an integer;

[0044] S30. Based on the error of each flow point at temperature t℃, perform piecewise fitting linear correction; S40. Based on the error of each flow point at (t+3*k)℃, perform piecewise fitting linear correction; S50. Use Lagrange interpolation method to determine the piecewise fitting formula for other temperature ranges.

[0045] The invention has a simple process and convenient operation, and can compensate for flow rates at different temperatures to ensure that all flow points within the entire temperature range can meet accuracy requirements.

[0046] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings.

[0047] The present invention provides an ultrasonic water meter flow temperature compensation method, which is applied to the temperature compensation process of the ultrasonic water meter. Figure 1 As shown, in this embodiment, the ultrasonic water meter flow temperature compensation method includes the following steps:

[0048] S10. Measure the error of each flow point of the ultrasonic water meter at a certain temperature t℃ within the normal temperature range.

[0049] Specifically, in this embodiment, the error of each point of the ultrasonic water meter at a certain temperature point t within the normal temperature range (20±5°C) is measured. Within the full range, the measurement points are evenly selected, not less than 20 points, each measurement point is measured multiple times, and the average value is calculated. If at the instantaneous flow rate q, the water flow of the standard meter is V, and the water flow of the meter under test is Vp, then the error is:

[0050] K = (Vp-V) / V;

[0051] The average error of n times is:

[0052] Kp=(K1+K2+K3+……+K n ) / n;

[0053] Where n≥3, and Qp / q=Vp / V;

[0054] The average instantaneous flow expression of the inspected meter is as follows:

[0055] Qp=(1+Kp)*q.

[0056] S20. Taking the temperature t℃ as the reference, measure the error of each flow point of the ultrasonic water meter at (t+3*k)℃, where k is an integer.

[0057] Specifically, in this embodiment, 0≤t+3*k≤50, the temperature range is determined according to design requirements, and 0-50°C is taken as an example in the embodiment of the present invention, and the average instantaneous flow Qp of the inspected meter corresponding to each standard flow q is calculated.

[0058] S30, based on the error of each flow point at temperature t°C, perform piecewise fitting linear correction.

[0059] Specifically, in this embodiment, according to the corresponding data table of the instantaneous flow rate q of each standard meter and the average instantaneous flow rate Qp of the meter under test at temperature t°C, a segmented fitting linear correction is performed, and the entire flow segment is divided into several segments. Each segment is corrected using a first-order equation. The error is adjusted to within the 1% error range and as close to 0 as possible using fitting software. Assuming that it is divided into 2 segments (the specific number of segments is determined according to the fitting of the measurement error result), then:

[0060] q t01 =k t01 *Qp+b t01 , 1.1*Q4>Qp≥a;

[0061] q t02 =k t02 *Qp+b t02 , a>Qp≥Q1;

[0062] where q t01 ,q t02 is the corrected flow rate, and the error with the standard instantaneous flow rate q is no more than 1%, and a is the segmentation point.

[0063] S40. Based on the error of each flow point at (t+3*k)°C, perform piecewise fitting linear correction.

[0064] Specifically, in this embodiment, the corresponding data table of the instantaneous flow rate q of each standard meter and the average instantaneous flow rate Qp of the meter under test at each temperature of (t+3*k)℃ is calculated according to the method of the above step S30, and the segmentation point a at normal temperature is used as the segmentation point to perform segmented fitting linear correction so that the error is within 1.5%. For example, assuming that when k=1, that is, the temperature is (t+3)℃, the error fitting formula is as follows:

[0065] q t11 =k t11 *Qp+b t11 ;

[0066] q t12 =k t12 *Qp+b t12 ;

[0067] Among them, q t11 ,q t12 It is the corrected flow rate, and the error with the standard instantaneous flow rate q is no more than 1.5%.

[0068] S50. Use Lagrange interpolation method to determine the piecewise fitting formula for other temperature ranges.

[0069] Specifically, in this embodiment, when the actual temperature T is between t°C and (t+3)°C, the Lagrange interpolation method is used to obtain:

[0070]

[0071] Then the coefficient of the segmented correction fitting formula at T℃ is calculated as:

[0072]

[0073] Similarly, we can get:

[0074]

[0075] The piecewise fitting formula at temperature T℃ is:

[0076]

[0077] According to the above steps, temperature compensation in the full temperature range and the full flow section can be achieved.

[0078] An embodiment of the present invention further provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, any one of the methods in the present embodiment is implemented.

[0079] An embodiment of the present invention further provides an electronic terminal, comprising: a processor and a memory; the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory, so that the terminal executes any one of the methods in this embodiment.

[0080] The computer-readable storage medium in this embodiment can be understood by ordinary technicians in this field: all or part of the steps of implementing the above-mentioned method embodiments can be completed by hardware related to the computer program. The aforementioned computer program can be stored in a computer-readable storage medium. When the program is executed, the steps of the above-mentioned method embodiments are executed; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk and other media that can store program codes.

[0081] The electronic terminal provided in this embodiment includes a processor, a memory, a transceiver and a communication interface. The memory and the communication interface are connected to the processor and the transceiver and complete communication with each other. The memory is used to store computer programs, the communication interface is used to communicate, and the processor and the transceiver are used to run computer programs so that the electronic terminal executes each step of the above method.

[0082] Compared with the prior art, the flow temperature compensation method of the ultrasonic water meter described in the above embodiment has the biggest problem of the current ultrasonic water meter that the temperature has a great influence on it. In the prior art, a fixed formula temperature correction is performed, and the flow at different temperatures cannot be accurately compensated, and it cannot be guaranteed that all flow points can meet the accuracy requirements in the entire temperature range. The present invention has a simple process and convenient operation. It takes the flow point at room temperature as the benchmark, which is convenient for production calibration and meter inspection. It uses the measured error coefficient of each flow point at each temperature for compensation. The ultrasonic pipe section and transducer under the same mold have universal applicability, and can ensure that after compensation, the accuracy requirements can be met in the full temperature and full flow range.

[0083] Obviously, the embodiments described above are only preferred embodiments of the present invention, rather than all embodiments. The preferred embodiments of the present invention are shown in the accompanying drawings, but they do not limit the patent scope of the present invention. The present invention can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive. Although the present invention has been described in detail with reference to the aforementioned embodiments, for those skilled in the art, it is still possible to modify the technical solutions recorded in the aforementioned specific embodiments, or to perform equivalent replacements for some of the technical features therein. Any equivalent structure made using the contents of the specification and drawings of the present invention, directly or indirectly used in other related technical fields, is also within the scope of patent protection of the present invention.

Claims

1. A method for flow temperature compensation of an ultrasonic water meter, characterized in that: The following steps are involved: S10, measure the error of each flow point of the ultrasonic water meter at a certain temperature t℃ within the normal temperature range; S20, taking temperature t℃ as the reference, measure the error of each flow point of the ultrasonic water meter at (t+3*k)℃, where k is an integer; S30, based on the error of each flow point at temperature t°C, perform piecewise fitting linear correction; S40, based on the error of each flow point at (t+3*k)℃, perform piecewise fitting linear correction; S50. Use Lagrange interpolation method to determine the piecewise fitting formula for other temperature ranges.

2. The method for flow temperature compensation of an ultrasonic water meter according to claim 1, characterized in that: If at the instantaneous flow rate q, the water flow of the standard meter is V, the water flow of the meter under test is Vp, and Qp is the instantaneous flow rate of the meter under test, then the error expression is as follows: K = (Vp-V) / y; The average error of n times is: Kp=(K1+K2+K3+……+K n ) / n; Where n≥3, and Qp / q=Vp / V; The average instantaneous flow expression of the inspected meter is as follows: Qp=(1+Kp)*q.

3. The method for flow temperature compensation of an ultrasonic water meter according to claim 2, characterized in that: In step S30, assuming that the entire flow segment is divided into two segments, then: q t01 =k t01 *Qp+b t01 ,1.1*Q4>Qp≥a; q t02 =k t02 *Qp+b t02 ,a>Qp≥Q1; where q t01 ,q t02 is the corrected flow rate, and the error with the standard instantaneous flow rate q is no more than 1%, and a is the segmentation point.

4. The method for flow temperature compensation of an ultrasonic water meter according to claim 3, characterized in that: In step S40, the segmented point a at room temperature is used for segmented fitting linear correction. When k=1, that is, the temperature is (t+3)°C, the error fitting formula is as follows: q t11 =k t11 *Qp+b t11 ; q t12 =k t12 *Qp+b t12 ; Among them, q t11 ,q t12 It is the corrected flow rate, and the error with the standard instantaneous flow rate q is no more than 1.5%.

5. The method for flow temperature compensation of an ultrasonic water meter according to claim 4, characterized in that: In step S50, when the actual temperature T is between t°C and (t+3)°C, the Lagrange interpolation method is used to obtain: Then the coefficient of the piecewise correction fitting formula at T℃ is:

6. The method for flow temperature compensation of an ultrasonic water meter according to claim 5, characterized in that: The piecewise fitting formula at temperature T℃ is:

7. The method for temperature compensation of ultrasonic water meter flow rate according to claim 1, characterized in that: In the step S10, the normal temperature range is 20±5°C, and the number of flow points is not less than 20.

8. The method for temperature compensation of ultrasonic water meter flow rate according to claim 1, characterized in that: In the step S20, 0≤t+3*k≤50.

9. A computer-readable storage medium, characterized in that: The storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 8 is implemented.

10. An electronic terminal, characterized in that: include: Processor and memory; The memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory, so that the terminal executes the method according to any one of claims 1 to 8.

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