阅读说明：本技术 一种流量计量方法、装置及系统 (flow metering method, device and system ) 是由 史晋峰 吴彦强 张鹏 郑亮 于 2019-10-17 设计创作，主要内容包括：本发明提供了一种流量计量方法、装置及系统,依据目标流量的流量范围确定目标流量计量设备,所述目标流量计量设备包括高频差压扫描阀、节流装置以及所述高频差压扫描阀与所述节流装置之间的高压测量管路和低压测量管路；利用所述高频差压扫描阀采集所述目标流量通过所述节流装置在不同采样点在所述高压测量管路和所述低压测量管路之间的差压值；将不同采样点的所述差压值输入所述目标流量计量设备预先标定的流量标定模型中进行计算,得到目标流量在不同采样点的流量值,实现了对高动态短周期流量的精确测量。(The invention provides a flow measuring method, a device and a system, which determine target flow measuring equipment according to the flow range of target flow, wherein the target flow measuring equipment comprises a high-frequency differential pressure scanning valve, a throttling device, and a high-pressure measuring pipeline and a low-pressure measuring pipeline between the high-frequency differential pressure scanning valve and the throttling device; collecting differential pressure values of the target flow between the high-pressure measuring pipeline and the low-pressure measuring pipeline at different sampling points through the throttling device by using the high-frequency differential pressure scanning valve; and inputting the differential pressure values of different sampling points into a flow calibration model calibrated in advance by the target flow metering equipment for calculation to obtain flow values of the target flow at different sampling points, thereby realizing accurate measurement of high-dynamic short-period flow.)

1. A flow metering method, comprising:

Determining target flow metering equipment according to a flow range of target flow, wherein the target flow metering equipment comprises a high-frequency differential pressure scanning valve, a throttling device, and a high-pressure measuring pipeline and a low-pressure measuring pipeline which are arranged between the high-frequency differential pressure scanning valve and the throttling device;

Collecting differential pressure values of the target flow between the high-pressure measuring pipeline and the low-pressure measuring pipeline at different sampling points through the throttling device by using the high-frequency differential pressure scanning valve;

And inputting the differential pressure values of different sampling points into a flow calibration model calibrated in advance by the target flow metering equipment for calculation to obtain flow values of the target flow at different sampling points.

2. The method according to claim 1, wherein the number of the target flow metering devices is at least 1, and each target flow metering device corresponds to one flow calibration model.

3. the method of claim 1, further comprising:

obtaining calibration recording parameters of the target flow metering equipment under a steady-state flow working condition and a dynamic flow working condition;

and constructing a flow calibration model, and calculating parameter values in the flow calibration model through calibration recording parameters of the target flow metering equipment under the steady-state flow working condition and the dynamic flow working condition to obtain the flow calibration model of the target flow metering equipment.

4. the method of claim 3, wherein the obtaining of the calibration record parameters of the target flow metering device under the steady-state flow condition and the dynamic flow condition comprises:

Setting a calibration flow point under a steady-state working condition;

Controlling the liquid medium power source to output a flow value to be calibrated;

Collecting flow-pressure difference characteristic parameters of each calibration flow point of the target flow metering equipment under a steady-state working condition;

setting a calibration flow point under a dynamic working condition;

controlling the liquid medium power source to output a change step quantity of a flow value to be calibrated;

And collecting the flow-pressure difference characteristic parameters of each calibrated flow point of the target flow metering equipment under the dynamic working condition.

5. The method according to claim 3, wherein the constructing a flow calibration model, and calculating parameter values in the flow calibration model through calibration recorded parameters of the target flow metering device under a steady-state flow condition and a dynamic flow condition to obtain the flow calibration model of the target flow metering device comprises:

constructing a flow calibration model based on an average sliding autoregressive model, and setting an optimization constraint condition of the flow calibration model;

And calculating parameters of a flow calibration model meeting the optimization constraint condition by using a least square parameter identification algorithm according to the flow-pressure difference specific parameters of each calibration flow point under the steady-state working condition and the dynamic working condition to obtain the flow calibration model of the target flow metering equipment.

6. a flow metering device, comprising:

The flow metering equipment determining unit is used for determining target flow metering equipment according to the flow range of target flow, and the target flow metering equipment comprises a high-frequency differential pressure scanning valve, a throttling device, and a high-pressure measuring pipeline and a low-pressure measuring pipeline which are arranged between the high-frequency differential pressure scanning valve and the throttling device;

The differential pressure value acquisition unit is used for acquiring the differential pressure value of the target flow between the high-pressure measurement pipeline and the low-pressure measurement pipeline at different sampling points through the throttling device by utilizing the high-frequency differential pressure scanning valve;

and the flow value calculation unit is used for inputting the differential pressure values of different sampling points into a flow calibration model calibrated in advance by the target flow metering equipment for calculation to obtain the flow values of the target flow at different sampling points.

7. The apparatus of claim 6, further comprising:

The calibration recording parameter acquisition unit is used for acquiring calibration recording parameters of the target flow metering equipment under a steady-state flow working condition and a dynamic flow working condition;

and the flow calibration model construction unit is used for constructing a flow calibration model, and calculating parameter values in the flow calibration model through the calibration recording parameters of the target flow metering equipment under the steady-state flow working condition and the dynamic flow working condition to obtain the flow calibration model of the target flow metering equipment.

8. the apparatus according to claim 7, wherein the calibration record parameter obtaining unit is specifically configured to:

Setting a calibration flow point under a steady-state working condition;

Controlling the liquid medium power source to output a flow value to be calibrated;

collecting flow-pressure difference characteristic parameters of each calibration flow point of the target flow metering equipment under a steady-state working condition;

Setting a calibration flow point under a dynamic working condition;

controlling the liquid medium power source to output a change step quantity of a flow value to be calibrated;

and collecting the flow-pressure difference characteristic parameters of each calibrated flow point of the target flow metering equipment under the dynamic working condition.

9. the apparatus according to claim 7, wherein the flow calibration model construction unit is specifically configured to:

Constructing a flow calibration model based on an average sliding autoregressive model, and setting an optimization constraint condition of the flow calibration model;

and calculating parameters of a flow calibration model meeting the optimization constraint condition by using a least square parameter identification algorithm according to the flow-pressure difference specific parameters of each calibration flow point under the steady-state working condition and the dynamic working condition to obtain the flow calibration model of the target flow metering equipment.

10. a flow metering system, comprising: the system comprises a calibration system computer, at least one flow metering device, a liquid medium power source and a liquid medium load device;

the flow metering equipment comprises a high-frequency differential pressure scanning valve, a throttling device, and a high-pressure measuring pipeline and a low-pressure measuring pipeline which are arranged between the high-frequency differential pressure scanning valve and the throttling device;

The calibration system computer is used for executing a flow measurement method according to any one of claims 1 to 5.

Technical Field

The invention relates to the technical field of flow measurement, in particular to a flow measurement method, a device and a system.

Background

referring to fig. 1, the flow rate change process of a high dynamic short period requires accurate measurement of the flow rate of a filling process within 0.2 second. Wherein the flow rate of the liquid medium is linearly increased from 0t/h to 20t/h within 0-0.1 s; the flow of the liquid medium is kept stable within 0.1-0.15 seconds; the flow rate of the liquid medium is linearly reduced from 20t/h to 0t/h within 0.15-0.2 seconds, so that the accurate metering of the flow rate of the liquid medium with the period of 0.2 seconds is completed.

the existing mature flowmeter products have products with different measurement principles such as an electromagnetic flowmeter, an ultrasonic flowmeter, a turbine flowmeter, a coriolis flowmeter and the like, but the flow measurement frequency effect of the flowmeter products is slow, and the highest measurement frequency is usually 10Hz, namely: only 10 times of flow measurement signals are output to the outside within 1 second, and therefore the product is suitable for process measurement occasions and is not suitable for measurement of dynamic flow in a high-dynamic short period.

disclosure of Invention

in view of this, the invention provides a flow measuring method, device and system, which can realize accurate measurement of high-dynamic short-period flow.

in order to achieve the above purpose, the invention provides the following specific technical scheme:

A flow metering method comprising:

Determining target flow metering equipment according to a flow range of target flow, wherein the target flow metering equipment comprises a high-frequency differential pressure scanning valve, a throttling device, and a high-pressure measuring pipeline and a low-pressure measuring pipeline which are arranged between the high-frequency differential pressure scanning valve and the throttling device;

Collecting differential pressure values of the target flow between the high-pressure measuring pipeline and the low-pressure measuring pipeline at different sampling points through the throttling device by using the high-frequency differential pressure scanning valve;

And inputting the differential pressure values of different sampling points into a flow calibration model calibrated in advance by the target flow metering equipment for calculation to obtain flow values of the target flow at different sampling points.

Optionally, the number of the target flow metering devices is at least 1, and each target flow metering device corresponds to one flow calibration model.

Optionally, the method further includes:

Obtaining calibration recording parameters of the target flow metering equipment under a steady-state flow working condition and a dynamic flow working condition;

and constructing a flow calibration model, and calculating parameter values in the flow calibration model through calibration recording parameters of the target flow metering equipment under the steady-state flow working condition and the dynamic flow working condition to obtain the flow calibration model of the target flow metering equipment.

Optionally, the obtaining of the calibration recording parameter of the target flow metering device under the steady-state flow condition and the dynamic flow condition includes:

Setting a calibration flow point under a steady-state working condition;

controlling the liquid medium power source to output a flow value to be calibrated;

collecting flow-pressure difference characteristic parameters of each calibration flow point of the target flow metering equipment under a steady-state working condition;

Setting a calibration flow point under a dynamic working condition;

controlling the liquid medium power source to output a change step quantity of a flow value to be calibrated;

and collecting the flow-pressure difference characteristic parameters of each calibrated flow point of the target flow metering equipment under the dynamic working condition.

optionally, the constructing a flow calibration model, and calculating a parameter value in the flow calibration model through calibration recording parameters of the target flow metering device under the steady-state flow condition and the dynamic flow condition to obtain the flow calibration model of the target flow metering device includes:

constructing a flow calibration model based on an average sliding autoregressive model, and setting an optimization constraint condition of the flow calibration model;

and calculating parameters of a flow calibration model meeting the optimization constraint condition by using a least square parameter identification algorithm according to the flow-pressure difference specific parameters of each calibration flow point under the steady-state working condition and the dynamic working condition to obtain the flow calibration model of the target flow metering equipment.

a flow metering device comprising:

The flow metering equipment determining unit is used for determining target flow metering equipment according to the flow range of target flow, and the target flow metering equipment comprises a high-frequency differential pressure scanning valve, a throttling device, and a high-pressure measuring pipeline and a low-pressure measuring pipeline which are arranged between the high-frequency differential pressure scanning valve and the throttling device;

The differential pressure value acquisition unit is used for acquiring the differential pressure value of the target flow between the high-pressure measurement pipeline and the low-pressure measurement pipeline at different sampling points through the throttling device by utilizing the high-frequency differential pressure scanning valve;

and the flow value calculation unit is used for inputting the differential pressure values of different sampling points into a flow calibration model calibrated in advance by the target flow metering equipment for calculation to obtain the flow values of the target flow at different sampling points.

Optionally, the number of the target flow metering devices is at least 1, and each target flow metering device corresponds to one flow calibration model.

optionally, the apparatus further comprises:

The calibration recording parameter acquisition unit is used for acquiring calibration recording parameters of the target flow metering equipment under a steady-state flow working condition and a dynamic flow working condition;

and the flow calibration model construction unit is used for constructing a flow calibration model, and calculating parameter values in the flow calibration model through the calibration recording parameters of the target flow metering equipment under the steady-state flow working condition and the dynamic flow working condition to obtain the flow calibration model of the target flow metering equipment.

Optionally, the calibration recording parameter obtaining unit is specifically configured to:

setting a calibration flow point under a steady-state working condition;

controlling the liquid medium power source to output a flow value to be calibrated;

Collecting flow-pressure difference characteristic parameters of each calibration flow point of the target flow metering equipment under a steady-state working condition;

setting a calibration flow point under a dynamic working condition;

controlling the liquid medium power source to output a change step quantity of a flow value to be calibrated;

and collecting the flow-pressure difference characteristic parameters of each calibrated flow point of the target flow metering equipment under the dynamic working condition.

Optionally, the flow calibration model building unit is specifically configured to:

Constructing a flow calibration model based on an average sliding autoregressive model, and setting an optimization constraint condition of the flow calibration model;

and calculating parameters of a flow calibration model meeting the optimization constraint condition by using a least square parameter identification algorithm according to the flow-pressure difference specific parameters of each calibration flow point under the steady-state working condition and the dynamic working condition to obtain the flow calibration model of the target flow metering equipment.

a flow metering system comprising: the system comprises a calibration system computer, at least one flow metering device, a liquid medium power source and a liquid medium load device;

the flow metering equipment comprises a high-frequency differential pressure scanning valve, a throttling device, and a high-pressure measuring pipeline and a low-pressure measuring pipeline which are arranged between the high-frequency differential pressure scanning valve and the throttling device;

the calibration system computer is adapted to perform a flow metering method as described in any of the above.

compared with the prior art, the invention has the following beneficial effects:

The flow metering method disclosed by the invention meets the high-frequency response metering requirement of flow metering based on the high-frequency differential pressure scanning valve and the throttling device of the flow metering equipment, and realizes accurate metering of flow in the high-dynamic short-period flow change process by utilizing a pre-calibrated flow calibration model after acquiring the pressure difference values of different sampling points.

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 description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

FIG. 1 is a schematic diagram of a high dynamic short period flow variation process;

FIG. 2 is a schematic flow chart of a flow measurement method according to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a flow metering device according to an embodiment of the present invention;

FIG. 4 is a schematic flowchart of a method for obtaining calibration recording parameters under a steady-state flow condition and a dynamic flow condition according to an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a flow metering device according to an embodiment of the present invention;

Fig. 6 is a schematic structural diagram of a flow metering system according to an embodiment of the present invention.

Detailed Description

the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious 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.

The inventor researches the flow metering equipment commonly used at present to find that: the current commonly used flow metering equipment generally has the problem of low response frequency, such as an electromagnetic flowmeter, the flow metering is realized through the conversion between flow and voltage, and the problem of low excitation frequency is caused due to the hysteresis characteristic; the Coriolis flowmeter realizes flow measurement through conversion between flow and Coriolis force, and due to the reasons of structural safety and measurement accuracy of the measuring tube, the problem of low excitation frequency is caused by reducing excitation frequency, improving harmonic amplitude value and further improving the measurement accuracy of product phase difference; the turbine flowmeter realizes flow measurement through conversion between flow and rotating speed, and when the flow changes due to the rotational inertia of a product, the rotating speed needs to be changed for a long time, so that the problem of low response frequency is caused.

in order to solve the problem that the flow metering device generally has low response frequency, the embodiment discloses a flow metering method applied to a calibration system computer in a flow metering system, wherein the flow metering system comprises: the system comprises a calibration system computer, at least one flow metering device, a liquid medium power source and a liquid medium loading device. Referring to fig. 2, the flow measurement method disclosed in this embodiment specifically includes the following steps:

S101: determining target flow metering equipment according to a flow range of target flow, wherein the target flow metering equipment comprises a high-frequency differential pressure scanning valve, a throttling device, and a high-pressure measuring pipeline and a low-pressure measuring pipeline which are arranged between the high-frequency differential pressure scanning valve and the throttling device;

referring to fig. 3, fig. 3 is a schematic structural diagram of a flow rate metering device.

Because the metering range of the flow metering equipment is limited, different amounts of flow metering equipment may be required when metering the flows in different flow ranges, the number of the target flow metering equipment may be 1 or more, and if the flow range of the target flow is 1-500L/min, 3 target flow metering equipment are required to cooperate to complete the flow metering in the full range, wherein the metering range of the first flow metering equipment is 1-10L/min, the metering range of the second flow metering equipment is 10-80L/min, and the metering range of the third flow metering equipment is 80-500L/min.

the implementation manner of determining the target flow metering device may be: and switching on a signal bus between the target flow metering equipment and the calibration system computer, and switching off the signal bus between the target flow metering equipment and the calibration system computer in the system.

s102: collecting differential pressure values of the target flow between the high-pressure measuring pipeline and the low-pressure measuring pipeline at different sampling points through the throttling device by using the high-frequency differential pressure scanning valve;

When there are a plurality of target flow rate measuring devices, the flow rate value of the target flow rate in the high dynamic short period is measured by each of the target flow rate measuring devices in turn.

taking the above 3 target flow metering devices as an example, when the first flow metering device is used for metering, the calibration system computer, the liquid medium power source, the first flow metering device and the liquid medium load device form a metering system, the calibration system computer controls the liquid medium power source to output the target flow in the metering range of the first flow metering device, and the high-frequency differential pressure scanning valve of the first flow metering device collects the differential pressure values of the target flow between the high-pressure measuring pipeline and the low-pressure measuring pipeline at different sampling points through the throttling device.

s103: and inputting the differential pressure values of different sampling points into a flow calibration model calibrated in advance by the target flow metering equipment for calculation to obtain flow values of the target flow at different sampling points.

the flow calibration model may be a flow calibration model based on a mean-slip autoregressive model.

The mean-slip autoregressive model is as follows:

wherein Q represents a flow rate, Δ P represents a differential pressure, k represents a time characteristic parameter,Denotes the flow at time k, Δ P_kthe differential pressure at time k is represented, i represents the number of flow rates Q before time k for parameter identification, and Q_k-iIndicates the flow rate at the i-th time point before the k time point, j indicates the number of differential pressures Δ P before the k time point for parameter identification, Δ P_k-jindicating the differential pressure at the jth time point before time k. a is_iand b_jto representAnd variable Q_k-iand Δ P_k-jAssociated parameters to be identified.

It should be noted that before the target flow is measured, the target flow measurement device needs to be calibrated to obtain a flow calibration model of the target flow measurement device.

specifically, firstly, calibration recording parameters of the target flow metering device under a steady-state flow condition and a dynamic flow condition need to be obtained, then a flow calibration model is constructed, and parameter values in the flow calibration model are calculated through the calibration recording parameters of the target flow metering device under the steady-state flow condition and the dynamic flow condition, so as to obtain the flow calibration model of the target flow metering device.

referring to fig. 4, the process of obtaining the calibration recording parameters of the target flow rate measurement device under the steady-state flow rate working condition and the dynamic flow rate working condition is as follows:

S401: setting a calibration flow point under a steady-state working condition;

the more the number of the calibration flow points, the higher the accuracy of the subsequent flow measurement, for example, the flow range is 10L/min-100L/min, the calibration flow points are as follows: 10L/min, 20L/min, 30L/min, 40L/min, 50L/min, 60L/min, 70L/min, 80L/min, 90L/min, and 100L/min.

s402: controlling the liquid medium power source to output a flow value to be calibrated;

Inputting a specific flow value to be calibrated in a calibration system computer, and controlling a liquid medium power source to realize that the flow of the liquid medium runs at a calibration flow point.

S403: collecting flow-pressure difference characteristic parameters of each calibration flow point of target flow metering equipment under a steady-state working condition;

And collecting a differential pressure value, displacement, volume and flow parameters of the target flow metering equipment, and storing the flow-differential pressure characteristic parameters of each calibrated flow point in 60 seconds into a system flow database, wherein the flow-differential pressure characteristic parameters represent the corresponding relation between flow and differential pressure.

S404: setting a calibration flow point under a dynamic working condition;

when the flow-pressure difference characteristic parameters of all the calibration flow points of the target flow metering equipment under the steady-state working condition are completely acquired, setting the calibration flow points under the dynamic working condition, such as: the calibration flow points under the steady state working condition are as follows: 10L/min, 20L/min, 30L/min, 40L/min, 50L/min, 60L/min, 70L/min, 80L/min, 90L/min, and 100L/min. The number of the calibration flow points under the dynamic condition is 9, that is, the transition process between any two adjacent calibration flow points under the steady-state condition.

s405: controlling the liquid medium power source to output a change step quantity of a flow value to be calibrated;

s406: and collecting the flow-pressure difference characteristic parameters of each calibrated flow point of the target flow metering equipment under the dynamic working condition.

And collecting the differential pressure value, displacement, volume and flow parameters of the flow metering equipment in the transition process of each calibrated flow point, and storing the flow-differential pressure characteristic parameters in 60 seconds (30 seconds before and after the transition process) into a system flow database.

Calculating parameters of a flow calibration model by using a least square parameter identification algorithm according to flow-pressure difference specific parameters of each calibration flow point under a steady state working condition and a dynamic working condition, wherein the constructed flow calibration model is as follows:

Setting an optimization constraint condition of the flow calibration model, so that the square of the difference between the real flow value and the calculated flow value is minimum, namely, the deviation degree between the real flow value and the calculated flow value is minimum, specifically, the expression of the optimization constraint condition is as follows:

In combination with the flow calibration model, the expression of the optimization constraint condition is as follows:

calculating and calculating parameters of the flow calibration model meeting the optimization constraint condition by using a least square parameter identification algorithm, specifically, for a_iand b_jcalculating partial derivatives, and setting the partial derivatives to 0 to obtain a matrix equation as follows:

By solving the matrix, a is obtained_iand b_jSo as to obtain a flow calibration model of the target flow metering device.

based on the flow metering method disclosed in the above embodiments, the present embodiment correspondingly discloses a flow metering device, please refer to fig. 5, and the device includes:

a flow metering device determining unit 501, configured to determine a target flow metering device according to a flow range of a target flow, where the target flow metering device includes a high-frequency differential pressure scanning valve, a throttling device, and a high-pressure measuring pipeline and a low-pressure measuring pipeline between the high-frequency differential pressure scanning valve and the throttling device;

a differential pressure value acquisition unit 502, configured to acquire, by using the high-frequency differential pressure scanning valve, a differential pressure value of the target flow between the high-pressure measurement pipeline and the low-pressure measurement pipeline at different sampling points through the throttling device;

and a flow value calculation unit 503, configured to input the differential pressure values at different sampling points into a flow calibration model calibrated in advance by the target flow metering device for calculation, so as to obtain flow values of the target flow at different sampling points.

optionally, the number of the target flow metering devices is at least 1, and each target flow metering device corresponds to one flow calibration model.

optionally, the apparatus further comprises:

The calibration recording parameter acquisition unit is used for acquiring calibration recording parameters of the target flow metering equipment under a steady-state flow working condition and a dynamic flow working condition;

And the flow calibration model construction unit is used for constructing a flow calibration model, and calculating parameter values in the flow calibration model through the calibration recording parameters of the target flow metering equipment under the steady-state flow working condition and the dynamic flow working condition to obtain the flow calibration model of the target flow metering equipment.

optionally, the calibration recording parameter obtaining unit is specifically configured to:

setting a calibration flow point under a steady-state working condition;

controlling the liquid medium power source to output a flow value to be calibrated;

collecting flow-pressure difference characteristic parameters of each calibration flow point of the target flow metering equipment under a steady-state working condition;

setting a calibration flow point under a dynamic working condition;

controlling the liquid medium power source to output a change step quantity of a flow value to be calibrated;

And collecting the flow-pressure difference characteristic parameters of each calibrated flow point of the target flow metering equipment under the dynamic working condition.

Optionally, the flow calibration model building unit is specifically configured to:

constructing a flow calibration model based on an average sliding autoregressive model, and setting an optimization constraint condition of the flow calibration model;

and calculating parameters of a flow calibration model meeting the optimization constraint condition by using a least square parameter identification algorithm according to the flow-pressure difference specific parameters of each calibration flow point under the steady-state working condition and the dynamic working condition to obtain the flow calibration model of the target flow metering equipment.

The invention also discloses a flow metering system, comprising: the system comprises a calibration system computer, at least one flow metering device, a liquid medium power source and a liquid medium load device;

The flow metering equipment comprises a high-frequency differential pressure scanning valve, a throttling device, and a high-pressure measuring pipeline and a low-pressure measuring pipeline which are arranged between the high-frequency differential pressure scanning valve and the throttling device;

the calibration system computer is used for executing the following flow measurement method:

determining target flow metering equipment according to a flow range of target flow, wherein the target flow metering equipment comprises a high-frequency differential pressure scanning valve, a throttling device, and a high-pressure measuring pipeline and a low-pressure measuring pipeline which are arranged between the high-frequency differential pressure scanning valve and the throttling device;

collecting differential pressure values of the target flow between the high-pressure measuring pipeline and the low-pressure measuring pipeline at different sampling points through the throttling device by using the high-frequency differential pressure scanning valve;

And inputting the differential pressure values of different sampling points into a flow calibration model calibrated in advance by the target flow metering equipment for calculation to obtain flow values of the target flow at different sampling points.

furthermore, the number of the target flow metering devices is at least 1, and each target flow metering device corresponds to one flow calibration model.

Further, the method further comprises:

Obtaining calibration recording parameters of the target flow metering equipment under a steady-state flow working condition and a dynamic flow working condition;

and constructing a flow calibration model, and calculating parameter values in the flow calibration model through calibration recording parameters of the target flow metering equipment under the steady-state flow working condition and the dynamic flow working condition to obtain the flow calibration model of the target flow metering equipment.

Further, the acquiring of the calibration recording parameters of the target flow metering device under the steady-state flow condition and the dynamic flow condition includes:

Setting a calibration flow point under a steady-state working condition;

Controlling the liquid medium power source to output a flow value to be calibrated;

Collecting flow-pressure difference characteristic parameters of each calibration flow point of the target flow metering equipment under a steady-state working condition;

setting a calibration flow point under a dynamic working condition;

Controlling the liquid medium power source to output a change step quantity of a flow value to be calibrated;

and collecting the flow-pressure difference characteristic parameters of each calibrated flow point of the target flow metering equipment under the dynamic working condition.

Further, the constructing a flow calibration model, and calculating parameter values in the flow calibration model through calibration recording parameters of the target flow metering device under the steady-state flow condition and the dynamic flow condition to obtain the flow calibration model of the target flow metering device includes:

Constructing a flow calibration model based on an average sliding autoregressive model, and setting an optimization constraint condition of the flow calibration model;

and calculating parameters of a flow calibration model meeting the optimization constraint condition by using a least square parameter identification algorithm according to the flow-pressure difference specific parameters of each calibration flow point under the steady-state working condition and the dynamic working condition to obtain the flow calibration model of the target flow metering equipment.

specifically, if the target flow rate has a flow rate range of 1-500L/min, 3 flow rate metering devices are required to cooperate to complete the full-range flow rate metering due to the limited metering range of the flow rate metering devices, wherein the metering range of the first flow rate metering device is 1-10L/min, the metering range of the second flow rate metering device is 10-80L/min, and the metering range of the third flow rate metering device is 80-500L/min, please refer to fig. 6, which illustrates a flow rate metering system including 3 flow rate metering devices, where the first flow rate metering device includes a first high-frequency differential pressure scanning valve, a first throttling device, a first high-frequency differential pressure scanning valve, a high-pressure measuring pipeline and a low-pressure measuring pipeline between the first throttling device, and the second flow rate metering device includes a second high-frequency differential pressure scanning valve, a second throttling device, a second high-frequency differential pressure scanning valve, And the third flow metering equipment comprises a third high-frequency differential pressure scanning valve, a third throttling device, a third high-frequency differential pressure scanning valve, a high-pressure measuring pipeline and a low-pressure measuring pipeline which are arranged between the third throttling device and the third throttling device.

It should be noted that fig. 6 is only one example of the disclosed flow rate metering system, the number of flow rate metering devices in the disclosed flow rate metering system is not limited thereto, and the number of flow rate metering devices may be one or more than one.

In the calibration stage, a calibration system computer sequentially calibrates flow calibration models of 3 flow metering devices, taking a first flow metering device as an example, the calibration system computer firstly sets a calibration flow point under a steady-state working condition, then sends a control instruction to a liquid medium power source, controls the liquid medium power source to output a flow value which needs to be calibrated at the current calibration flow point, acquires a differential pressure value, displacement, volume and flow parameters of the first flow metering device, stores flow-differential pressure characteristic parameters of the current calibration flow point within 60 seconds into a system flow database, and then controls the liquid medium power source to output a flow value which needs to be calibrated at the next calibration flow point until all calibration of the calibration flow points under all the steady-state working conditions are completed. And then the computer of the calibration system sets a calibration flow point under the dynamic working condition, controls the liquid medium power source to output the change step quantity of the flow rate required to be calibrated at the current calibration flow point, acquires the differential pressure value, displacement, volume and flow rate parameters of the first flow rate measurement equipment, stores the flow rate-differential pressure characteristic parameters of the current calibration flow point in 60 seconds into a system flow rate database, and controls the liquid medium power source to output the change step quantity of the flow rate required to be calibrated at the next calibration flow point until the calibration of the calibration flow points under all dynamic working conditions is completely finished. And finally, calculating parameters of a flow calibration model meeting the optimization constraint condition by using a least square parameter identification algorithm according to the flow-pressure difference specific parameters of each calibration flow point under the steady-state working condition and the dynamic working condition to obtain the flow calibration model of the first flow metering equipment. And the calibration of the flow calibration models of the second flow metering device and the third flow metering device is completed in sequence in the same way as the first flow metering device.

in the metering stage, the calibration system computer controls the liquid medium power source to output target flow, and in the flow change process of high dynamic short period, the method comprises the steps of respectively and firstly acquiring differential pressure values of target flow at different sampling points through high-frequency differential pressure scanning valves of flow metering equipment, second flow metering equipment and third flow metering equipment by utilizing the flow metering equipment, the second flow metering equipment and the third flow metering equipment, inputting the differential pressure values of the first flow metering equipment at the different sampling points into a flow calibration model of the first flow metering equipment for calculation, inputting the differential pressure values of the second flow metering equipment at the different sampling points into a flow calibration model of the second flow metering equipment for calculation, inputting the differential pressure values of the third flow metering equipment at the different sampling points into a flow calibration model of the third flow metering equipment for calculation, and obtaining the flow values of the target flow at the different sampling points.

the flow metering system disclosed by the embodiment meets the high-frequency response metering requirement of flow metering based on the high-frequency differential pressure scanning valve and the throttling device of the flow metering equipment, and after pressure difference values of different sampling points are obtained, accurate metering of flow in the high-dynamic short-period flow change process is realized by utilizing a pre-calibrated flow calibration model.

the previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.