A flow rate collection method for flow meter

Abstract

The present invention belongs to a flow acquisition method. In order to solve the technical problems that, in current turbine flowmeters and Coriolis mass flowmeters, if the flow value is calculated by acquiring frequency value, when the linearity of the flowmeter is poor, the calculation error is large, and if the flow value is calculated by acquiring current signal, the calculation method is complicated, a flow acquisition method for flowmeter is provided: obtaining multiple groups of data pairs consisting of standard flow values ​​of the flowmeter and corresponding standard signal parameter values; establishing an acquisition model related to the flow value and the acquisition signal parameter value; using the data pairs obtained in step S1, according to the acquisition model of step S2, through the SLOPE formula and the INTERCEPT formula, obtaining the coefficient of the acquisition model; acquiring the signal parameter value, substituting it into the acquisition model, and obtaining the flow value.

Description

Technical Field

[0001] The invention specifically relates to a flow rate collection method of a flow meter. Background Art

[0002] Turbine flowmeters and Coriolis mass flowmeters usually have three types of signals: frequency signal, current signal, and direct reading signal.

[0003] When collecting frequency signals, users generally directly use the single instrument coefficient value k given in the flow meter certificate and the collected frequency value through Flow calculation, where q is the volume flow and f is the frequency. When the flow meter has poor linearity, the calculation error of this method is large. When collecting current signals, users generally directly use the standard flow value given in the flow meter certificate and the collected current value to calculate the flow, but this method is relatively complicated and requires fitting two linear equations through the three-point data given in the certificate. When using it, substitute the collected current value into one of the equations for calculation to obtain the volume flow value. Summary of the invention

[0004] The present invention provides a flow collection method for a flow meter to solve the technical problems that, in current turbine flow meters and Coriolis mass flow meters, if the flow value is calculated by collecting frequency values, the calculation error is large when the linearity of the flow meter is poor, and if the flow value is calculated by collecting current signals, the calculation method is complicated.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A flow rate collection method of a flow meter, which is special in that it includes the following steps:

[0007] S1, obtaining multiple sets of data pairs consisting of standard flow values ​​of the flow meter and corresponding standard signal parameter values;

[0008] S2, establishing a collection model related to flow value and collection signal parameter value;

[0009] S3, using the data pair obtained in step S1, according to the acquisition model of step S2, through the SLOPE formula and the INTERCEPT formula, to obtain the coefficients of the acquisition model;

[0010] S4, collect signal parameter values, substitute them into the collection model, and obtain the flow value.

[0011] Further, in step S1, the standard signal parameter value is a standard frequency value, or a standard current value minus a minimum value of the collected current.

[0012] Furthermore, the minimum value of the collection current is 4 mA.

[0013] Furthermore, the acquisition model is q=Am+B, wherein q is the volume flow, m is the acquisition signal parameter value, A is the first parameter of the acquisition model, and B is the second parameter of the acquisition model.

[0014] Furthermore, step S3 specifically includes substituting the standard flow value in the data pair obtained in step S1 into q in the acquisition model, substituting the standard signal parameter value in the data pair obtained in step S1 into m in the acquisition model, and obtaining A and B in the acquisition model through the least squares fitting method.

[0015] Further, in step S1, the flow meter is a turbine flow meter, and the standard flow value is a standard volume flow value; in step S4, obtaining the flow value is specifically obtaining a volume flow value;

[0016] Alternatively, in step S1, the flow meter is a Coriolis mass flow meter, and the standard flow value is a standard mass flow value; in step S4, obtaining the flow value is specifically obtaining a mass flow value;

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. The flow collection method of the flow meter of the present invention establishes a collection model for efficiently and accurately collecting flow values. The parameters in the collection model are determined according to the standard flow value in the flow meter certificate and the corresponding standard signal parameter value. When collecting flow, the collection signal parameter value can be directly substituted into the collection model, so that the measured value of the volume flow can be obtained quickly and accurately, which is not affected by the linearity of the flow meter, and the measurement is simple and easy to operate, which effectively improves the measurement accuracy.

[0019] 2. The flow collection method of the flow meter of the present invention can determine the collection model by the standard frequency value in the standard signal parameter value, or by the standard current value. If it is determined by the standard current value, the standard current value is also processed so that the standard current value is subtracted from the minimum value of the collection current to meet the verification procedures.

[0020] 3. The flow rate collection method of the flow meter of the present invention determines the coefficients of the collection model by the least square fitting method, which can effectively ensure the accuracy of the collection model.

[0021] 4. The flow rate collection method of the flow meter of the present invention is applicable to turbine flow meters or Coriolis mass flow meters, and has wide applicability and strong practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The present invention is a flow chart of the flow rate collection method of the flow meter. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0024] like Figure 1 The present invention provides a flow acquisition method of a flow meter based on a least squares fitting method, which can directly obtain the flow value through an acquisition model according to the acquired signal parameter value. The specific steps are as follows:

[0025] S1, obtain multiple groups of data pairs consisting of standard flow values ​​of the flow meter and corresponding standard signal parameter values, wherein the standard signal parameter values ​​are frequency values ​​for frequency parameter type flow meters and current values ​​for current parameter type flow meters. The measurement method of the present invention can be used for turbine flow meters and Coriolis mass flow meters.

[0026] S2, establishing a collection model related to volume flow and collection signal parameter values, the collection model can be specifically q=Am+B, wherein q is the flow value, m is the collection signal parameter value, A is the first parameter of the collection model, and B is the second parameter of the collection model.

[0027] S3, substitute the standard flow value in the data pair obtained in step S1 into q in the acquisition model, substitute the standard signal parameter value in the data pair obtained in step S1 into m in the acquisition model, and obtain A and B in the acquisition model through the SLOPE formula and the INTERCEPT formula based on the least squares fitting method.

[0028] S4, collect signal parameter values, substitute them into m in the collection model, and obtain the flow value.

[0029] The following are four specific embodiments of the present invention:

[0030] Embodiment 1

[0031] For turbine flowmeter, the data shown in Table 1 are obtained from a turbine flowmeter calibration certificate:

[0032] Table 1 Data sheet of the turbine flowmeter verification certificate in Example 1

[0033] Standard volume flow rate values Standard frequency value qv1 f1 qv2 f2 qv3 f3

[0034] Through the data pairs (qv1, f1), (qv2, f2), (qv3, f3), based on the least squares fitting method, the SLOPE formula is used to obtain A in the acquisition model q=Am+B, and the INTERCEPT formula is used to obtain B in the acquisition model q=Am+B. In actual use, after the frequency is collected, the volume flow rate can be obtained through the acquisition model.

[0035] Embodiment 2

[0036] Similar to the first embodiment, for the turbine flowmeter, Table 2 is the data obtained from the calibration certificate of a turbine flowmeter.

[0037] Table 2 Data sheet of the turbine flowmeter verification certificate in Example 2

[0038] Standard volume flow rate values Standard current value qv1' i1 qv2' i2 qv3' i3

[0039] Since the range of the collected current signal is 4-20mA, according to the verification standard, the above standard current value needs to be processed before the least squares fitting method can be applied for calculation. The specific processing method is: the value of i1 after processing is i11=i1-4, the value of i2 after processing is i12=i2-4, and the value of i3 after processing is i13=i3-4.

[0040] Through the processed data pairs (qv1', i11), (qv2', i12), (qv3', i13), based on the least squares fitting method, the SLOPE formula is used to obtain the A in the acquisition model q=Am+B, and the INTERCEPT formula is used to obtain the B in the acquisition model q=Am+B. In actual measurement, after the current I is collected, it is processed and then the volume flow is obtained through the acquisition model.

[0041] Embodiment 3

[0042] For the Coriolis mass flowmeter, the data shown in Table 3 are obtained from a Coriolis mass flowmeter calibration certificate:

[0043] Table 3 Coriolis mass flowmeter calibration certificate data sheet in Example 3

[0044] Standard mass flow value Standard frequency value qm1 f1’ qm2 f2’ qm3 f3’

[0045] Based on the least squares fitting method, the data pairs (qm1, f1'), (qm2, f2'), and (qm3, f3') are used to obtain A in the acquisition model q=Am+B using the SLOPE formula, and the acquisition model q=Am+B using the INTERCEPT formula. In actual use, after the frequency is acquired, the mass flow rate can be obtained through the acquisition model.

[0046] Embodiment 4

[0047] For the Coriolis mass flowmeter, Table 4 is the data obtained from the calibration certificate of a Coriolis mass flowmeter.

[0048] Table 4 Coriolis mass flowmeter calibration certificate data sheet in Example 4

[0049] Standard mass flow value Standard current value qm1' i1’ qm2' i2’ qm3' i3’

[0050] Since the range of the collected current signal is 4-20mA, according to the verification standard, the above standard current value needs to be processed before the least squares fitting method can be applied for calculation. The specific processing method is: the value after i1' processing is i11'=i1'-4, the value after i2' processing is i12'=i2'-4, and the value after i3' processing is i13'=i3'-4.

[0051] Through the processed data pairs (qm1', i11'), (qm2', i12'), (qm3', i13'), based on the least squares fitting method, the SLOPE formula is used to obtain the A in the acquisition model q=Am+B, and the INTERCEPT formula is used to obtain the B in the acquisition model q=Am+B. In actual measurement, after the current I' is collected, it is processed and then the mass flow is obtained through the acquisition model.

[0052] In the above embodiment, the volume flow value obtained by the turbine flowmeter can also be converted into a mass flow value according to the formula, and the mass flow value obtained by the Coriolis mass flowmeter can also be converted into a volume flow value according to the formula.

[0053] The measuring method of the present invention can simply and efficiently measure the volume flow of the flow meter, and the measurement result is more accurate and is not limited by the linearity of the flow meter itself.

[0054] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A flow rate collection method of a flow meter, characterized in that: The following steps are involved: S1, obtaining multiple sets of data pairs consisting of standard flow values ​​of the flow meter and corresponding standard signal parameter values; the standard signal parameter value is a standard frequency value, or a standard current value minus a minimum value of the collected current; S2, establishing a collection model related to the flow value and the collection signal parameter value; the collection model is q=Am+B, where q is the flow value, m is the collection signal parameter value, A is the first parameter of the collection model, and B is the second parameter of the collection model; S3, using the data pairs obtained in step S1, according to the acquisition model of step S2, and obtaining the coefficients of the acquisition model by a least squares fitting method; S4, substituting the collected signal parameter value into the collection model to obtain the flow value.

2. A flow rate collection method of a flow meter as claimed in claim 1, characterized in that: Specifically, step S3 substitutes the standard flow value in the data pair obtained in step S1 into q in the acquisition model, substitutes the standard signal parameter value in the data pair obtained in step S1 into m in the acquisition model, and obtains A and B in the acquisition model through the SLOPE formula and the INTERCEPT formula based on the least squares fitting method.

3. A flow rate collection method of a flow meter as claimed in claim 2, characterized in that: In step S1, the flow meter is a turbine flow meter, and the standard flow value is a standard volume flow value; in step S4, obtaining the flow value is specifically obtaining a volume flow value; Alternatively, in step S1, the flow meter is a Coriolis mass flow meter, and the standard flow value is a standard mass flow value; in step S4, obtaining the flow value is specifically obtaining a mass flow value.

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