A flow metering device, method and storage medium

Abstract

The present invention relates to the technical field of flow metering, and discloses a flow metering device, method and storage medium, wherein the device comprises a housing, a power generation mechanism, a data acquisition module and a data processing module, wherein the housing is connected to an inlet pipe, the power generation mechanism is arranged in the housing, and the power generation mechanism is used to detect the fluid flow of the inlet pipe and output an AC voltage; the data acquisition module is communicatively connected to the data processing module, the data acquisition module is used to obtain the AC voltage according to a preset sampling period and send it to the data processing module, and the data processing module is used to calculate the fluid flow according to the frequency of the AC voltage. This method can realize the measurement of small flow rates and improve the measurement accuracy at the same time.

Description

Technical Field

[0001] The present invention relates to the technical field of flow measurement, and in particular to a flow measurement device, method and storage medium. Background Art

[0002] At present, existing flow meters, such as water meters, are divided into rotor-type mechanical water meters, ultrasonic electronic water meters, electromagnetic electronic water meters, pulse water meters based on rotor-type mechanical water meters, etc. according to different measurement principles.

[0003] Among the existing water meters, mechanical water meters can only meet the measurement accuracy requirements within the set water pressure range, and are unable to measure very small flow rates (i.e., dripping phenomena); ultrasonic electronic water meters require external power supply, and the measurement is greatly affected by temperature, scale, foam, etc., and the measurement stability is insufficient; electromagnetic electronic water meters also require external power supply, and have high requirements for the resistivity stability of the fluid.

[0004] In summary, the measurement accuracy of various existing flow meters is not high and they are unable to measure small flow rates. Summary of the invention

[0005] The present invention provides a flow metering device, method and storage medium to achieve the metering of small flows and improve the metering accuracy.

[0006] In a first aspect, in order to solve the above technical problems, the present invention provides a flow metering device, comprising a housing, a power generation mechanism, a data acquisition module and a data processing module, wherein the housing is connected to an inlet pipe, the power generation mechanism is arranged in the housing, and the power generation mechanism is used to detect the fluid flow of the inlet pipe and output an AC voltage; the data acquisition module is communicatively connected to the data processing module, and the data acquisition module is used to obtain the AC voltage according to a preset sampling period and send it to the data processing module; the data processing module is configured as follows:

[0007] receiving the AC voltage and calculating a voltage frequency of the AC voltage;

[0008] Performing a fast Fourier transform on the voltage frequency to obtain a fundamental frequency;

[0009] According to the fundamental frequency and a preset flow coefficient database, a flow coefficient corresponding to the fundamental frequency is obtained;

[0010] Calculating the product of the sampling period and the flow coefficient to obtain the instantaneous flow in each sampling period;

[0011] All the instantaneous flow rates are accumulated to obtain the fluid flow rate.

[0012] Preferably, the power generation mechanism comprises a stator and a rotor, the rotor is used to rotate with the fluid, the rotation axis of the rotor is perpendicular to the flow direction of the fluid, and the data input end of the data acquisition module is connected to the output end of the stator.

[0013] Preferably, the power generation mechanism also includes a rectifier module and an energy storage module, the input end of the rectifier module is connected to the output end of the stator, the output end of the rectifier module is connected to the input end of the energy storage module, and the output end of the energy storage module is connected to the power input end of the data acquisition module.

[0014] Preferably, the flow coefficient database includes a fundamental frequency-flow coefficient relationship curve.

[0015] Preferably, the configuration process of the fundamental frequency-discharge coefficient relationship curve includes:

[0016] According to the preset m flow gears, m measurement voltage frequencies are obtained, where m is a positive integer greater than 1;

[0017] Performing fast Fourier transform on the m measured voltage frequencies respectively to obtain m measured fundamental wave frequencies;

[0018] Calculating according to the m measurement fundamental frequencies, the number of non-zero values ​​among the m measurement fundamental frequencies and a preset total flow rate, to obtain m measurement flow coefficients corresponding to the measurement fundamental frequencies;

[0019] Fitting is performed based on the m measured fundamental frequencies and the m measured flow coefficients to obtain a fundamental frequency-flow coefficient relationship curve.

[0020] Preferably, the flow rate gear is positively correlated with the cross-sectional area for fluid circulation in the inlet pipe, and the flow rate gear at least includes a maximum flow rate gear and a minimum flow rate gear.

[0021] Preferably, the calculation formula for measuring the flow coefficient is:

[0022] K=L / f*n

[0023] Wherein, K is the measured flow coefficient, L is the total flow, f is the measured fundamental frequency, and n is the number of non-zeros among the m measured fundamental frequencies.

[0024] Preferably, the device further comprises a display module, the display module is communicatively connected with the data processing module, and the display module is used to display the fluid flow rate and the working status of the flow metering device.

[0025] In a second aspect, the present invention provides a flow metering method, which is implemented based on the flow metering device according to any one of the first aspects, and the method comprises:

[0026] Acquiring an alternating current voltage output by a power generation mechanism, and calculating a voltage frequency of the alternating current voltage;

[0027] Performing a fast Fourier transform on the voltage frequency to obtain a fundamental frequency;

[0028] According to the fundamental frequency and a preset flow coefficient database, a flow coefficient corresponding to the fundamental frequency is obtained;

[0029] Calculating the product of the sampling period and the flow coefficient to obtain the instantaneous flow in each sampling period;

[0030] All the instantaneous flow rates are accumulated to obtain the fluid flow rate.

[0031] In a third aspect, the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium includes a stored computer program, wherein when the computer program is running, the device where the computer-readable storage medium is located is controlled to execute the flow metering method described in any one of the above-mentioned second aspects.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] The flow metering device provided by the present invention includes a shell, a power generation mechanism, a data acquisition module and a data processing module. The shell is connected to an inlet pipe, and the power generation mechanism is arranged in the shell. The power generation mechanism is used to detect the fluid flow in the inlet pipe and output an AC voltage; the data acquisition module is communicatively connected with the data processing module, and the data acquisition module is used to obtain the AC voltage according to a preset sampling period and send it to the data processing module.

[0034] When the fluid in the inlet pipe flows, the power generation mechanism can output an AC voltage. At this time, the data acquisition module obtains the AC voltage and sends it to the data processing module. The data processing module is configured to: receive the AC voltage and calculate the voltage frequency of the AC voltage; perform fast Fourier transform on the voltage frequency to obtain the fundamental frequency; obtain the flow coefficient corresponding to the fundamental frequency according to the fundamental frequency and the preset flow coefficient database; calculate the product of the sampling period and the flow coefficient to obtain the instantaneous flow in each sampling period; accumulate all the instantaneous flows to obtain the fluid flow. The flow of the fluid is calculated by the voltage frequency, and an AC voltage can be generated as long as the fluid flows, thereby realizing the measurement of small flows. At the same time, the flow is only related to the frequency of the AC voltage, and this frequency is real-time variable and measurable, that is, as the flow rate changes, the measurement accuracy can be dynamically adjusted by measuring the frequency of the AC voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic structural diagram of a flow metering device provided by a preferred embodiment of the present invention;

[0036] Figure 2 It is a data processing flow diagram provided by a preferred embodiment of the present invention;

[0037] Figure 3 It is a fundamental frequency-flow coefficient relationship curve diagram provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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.

[0039] Reference Figure 1 An embodiment of the present invention provides a flow metering device, including a shell, a power generation mechanism, a data acquisition module and a data processing module. The shell is connected to an inlet pipe, and the power generation mechanism is arranged in the shell. The power generation mechanism is used to detect the fluid flow in the inlet pipe and output an AC voltage; the data acquisition module is communicatively connected with the data processing module, and the data acquisition module is used to obtain the AC voltage according to a preset sampling period and send it to the data processing module.

[0040] Specifically, the power generation mechanism includes a stator and a rotor, the rotor is used to rotate with the fluid, the rotation axis of the rotor is perpendicular to the flow direction of the fluid, and the data input end of the data acquisition module is connected to the output end of the stator. Among them, the rotor includes a plurality of permanent magnets, and the plurality of permanent magnets form a Halbach array, which is conducive to reducing the air gap and increasing sensitivity. Taking the water meter as an example, the rotation axis of the rotor is perpendicular to the flow direction of the fluid, that is, the rotation axis is perpendicular to the horizontal plane, which is conducive to the rotor rotating with the water flow and reducing the friction of the rotor.

[0041] Furthermore, the power generation mechanism also includes a rectifier module and an energy storage module, the input end of the rectifier module is connected to the output end of the stator, the output end of the rectifier module is connected to the input end of the energy storage module, and the output end of the energy storage module is connected to the power input end of the data acquisition module. Preferably, the output end of the energy storage module is connected to a voltage stabilizing chip. In specific applications, the energy storage module can use a supercapacitor, and the supercapacitor outputs a stable voltage as a working power supply through a voltage stabilizing chip, without the need for external power supply, which further increases the practicality of the device.

[0042] In one embodiment, the data acquisition module is arranged on the housing, and the data acquisition module is integrated with the data processing module, and the energy storage module supplies power to the data acquisition module and the data processing module. In another embodiment, the data acquisition module is arranged on the housing, and the data processing module is arranged on the data processing terminal, and the energy storage module supplies power to the data acquisition module. It should be noted that as long as the data acquisition module and the data processing module are in communication connection, the present invention does not specifically limit the installation position and method of the two.

[0043] Exemplarily, the fluid generator uses a permanent magnet inner rotor and a coreless conductive coil in the stator part, which evenly constitutes a 6-phase voltage output of 12 poles and 6 pairs of coils. When water flows in the copper tube, it drives the permanent magnet inner rotor to rotate, and the 6 pairs of coils output voltage at the same time. The output voltage phase of each pair of coils differs by 60 degrees. The 6 groups of output voltages are rectified by bridge rectification, and the rectified output is output to a 5V supercapacitor through a voltage regulator tube. The supercapacitor then outputs a stable voltage as a working power supply through an LDO voltage regulator chip, so no external power supply is required.

[0044] Furthermore, 2 pairs of coils are selected from the 6 pairs of coils, and differential sampling is adopted with a sampling frequency of 10Khz and a sampling period of 1 / 10Khz to measure the coil output voltage. As the water pressure and water flow vary, the coil output is an approximate sinusoidal voltage with a frequency range of 0-600hz and a Vpp of 10V. The higher the frequency, the greater the water pressure difference, and the greater the flow rate flowing through the cross-section of the inlet pipe per unit time. Regardless of the diameter of the inlet pipe, the flow rate is only related to the frequency of the AC voltage and the circulation time. When a valve device, such as a faucet, is provided on the inlet pipe, the AC voltage frequency changes with the size of the faucet switch, and the frequency of the coil output voltage also changes with the adjustment of the water pressure at the water inlet. In specific applications, the data acquisition module obtains the AC voltage according to the sampling period and sends it to the data processing module.

[0045] Reference Figure 2 , the data processing module is used to perform the following steps:

[0046] S11, receiving the AC voltage and calculating the voltage frequency of the AC voltage;

[0047] S12, performing fast Fourier transform on the voltage frequency to obtain a fundamental frequency;

[0048] S13, obtaining a flow coefficient corresponding to the fundamental frequency according to the fundamental frequency and a preset flow coefficient database;

[0049] S14, calculating the product of the sampling period and the flow coefficient to obtain the instantaneous flow in each sampling period;

[0050] S15, accumulating all the instantaneous flow rates to obtain the fluid flow rate.

[0051] In step S11, the data processing module and the data acquisition module may adopt wired communication or wireless communication such as Bluetooth, ZigBee, WiFi, etc. to transmit AC voltage data. After receiving the AC voltage, the data processing module calculates the voltage frequency of the AC voltage.

[0052] In step S12, the voltage frequency is subjected to a fast Fourier transform to obtain a fundamental frequency. Specifically, a fast Fourier transform-related algorithm is pre-configured in the data processing module to perform a discrete Fourier transform on the voltage frequency to obtain a fundamental frequency.

[0053] In step S13, the flow coefficient corresponding to the fundamental frequency is obtained according to the fundamental frequency and a preset flow coefficient database. The flow coefficient database includes a fundamental frequency-flow coefficient relationship curve, such as Figure 3 Of course, in other embodiments, the flow coefficient database may also be in the form of a chart, an equation, etc. For example, the curve equation after fitting includes multiple straight lines, and the flow coefficient can be calculated by linear interpolation and a straight line equation. With i being a positive integer, when the fundamental frequency f x Falling on f i ,f i+1 When between, the corresponding flow coefficient K x =K i +(K i+1 -K i )*(f x -f i ) / (f i+1 -f i ).

[0054] In one embodiment, the configuration process of the fundamental frequency-discharge coefficient relationship curve includes:

[0055] According to the preset m flow gears, m measurement voltage frequencies are obtained, where m is a positive integer greater than 1;

[0056] Performing fast Fourier transform on the m measured voltage frequencies respectively to obtain m measured fundamental wave frequencies;

[0057] Calculating according to the m measurement fundamental frequencies, the number of non-zero values ​​among the m measurement fundamental frequencies and a preset total flow rate, to obtain m measurement flow coefficients corresponding to the measurement fundamental frequencies;

[0058] Fitting is performed based on the m measured fundamental frequencies and the m measured flow coefficients to obtain a fundamental frequency-flow coefficient relationship curve.

[0059] Furthermore, in order to increase the reliability of the data, the sampling groups are divided according to a preset frequency, and the measured voltage frequencies of multiple sampling groups are obtained, and the sampling points of adjacent sampling groups are partially overlapped.

[0060] Exemplarily, in the configuration process of the fundamental frequency-discharge coefficient relationship curve, the sampling frequency is set to 8Khz, and every 64 sampling points are grouped together to perform a fast Fourier transform (FFT) to obtain the measured fundamental frequency. At the same time, adjacent sampling groups overlap 32 sampling points, and the FFT transform is continuously performed on the 64 continuously overlapping sampling points to obtain the measured fundamental frequency every 4ms in turn. The multiple measured fundamental frequencies every 4ms are measured and calculated by the device, and the multiple measured fundamental frequencies and the number of measured fundamental frequencies that are not 0 are recorded. This measured fundamental frequency is basically fixed when the flow rate is stable. When the water inlet pipe is cut off, the measured fundamental frequency is immediately 0.

[0061] Then, calculation is performed according to the m measurement fundamental wave frequencies, the number of non-zero values ​​in the m measurement fundamental wave frequencies and a preset total flow rate to obtain m measurement flow coefficients corresponding to the measurement fundamental wave frequencies.

[0062] The calculation formula for the measured flow coefficient is:

[0063] K=L / f*n

[0064] Wherein, K is the measured flow coefficient, L is the total flow, f is the measured fundamental frequency, and n is the number of non-zeros among the m measured fundamental frequencies.

[0065] In this embodiment, a water volume of L liters is obtained by an instrument with an accuracy of 0.1 or even higher, and the water volume of L liters is taken as the total flow rate.

[0066] It should be noted that the flow level is positively correlated with the cross-sectional area for fluid circulation in the inlet pipe, and the flow level includes at least a maximum flow level and a minimum flow level. The inlet pipe can be equipped with a valve device, and by controlling the on-off size of the valve device, the increase or decrease of the cross-sectional area for fluid circulation in the inlet pipe can be controlled. For example, through a valve device such as a faucet to control the water flow, the maximum flow level is the flow level when the faucet is opened to the maximum, and the minimum flow level is the flow level when the faucet is closed to the minimum.

[0067] In specific applications, taking the water meter as an example, assuming that the maximum flow rate of the water meter is Q3 and the minimum flow rate is Q1, Q1 to Q3 are set to 10 levels respectively, and 10 groups of different fundamental frequency measurements and flow coefficient measurements are measured respectively. Through curve fitting, the fundamental frequency-flow coefficient relationship curve is obtained.

[0068] In steps S14 and S15, the product of the sampling period and the flow coefficient is calculated to obtain the instantaneous flow in each sampling period; all the instantaneous flow rates are accumulated to obtain the fluid flow rate.

[0069] It should be noted that the flow rate is related to time. The flow rate is the amount of water flowing out during the period T0-T1 from when the valve is opened to when it is closed. From a mathematical point of view, it is the integral of the unit flow rate in the T0-T1 time period. If the unit flow rate remains unchanged and is a constant, the flow rate is the unit flow rate multiplied by (T1-T0). In this embodiment, the flow coefficient is the unit flow rate in each sampling period, so the product of the sampling period and the flow coefficient is calculated to obtain the instantaneous flow rate in each sampling period. Finally, all the instantaneous flows are accumulated to obtain the fluid flow rate.

[0070] In a preferred embodiment, the device further comprises a display module, the display module is in communication with the data processing module, and the display module is used to display the fluid flow rate and the working state of the flow metering device. For example, the display module can display the water supply start indication, the water supply stop indication, the total amount of water delivered per second (since the start of the water supply this time), and the like.

[0071] The flow metering device provided by the present invention calculates the flow rate of the fluid through the voltage frequency. As long as the fluid flows, an AC voltage can be generated, thereby realizing the measurement of a small flow rate. At the same time, the flow rate is only related to the frequency of the AC voltage, and this frequency is variable and measurable in real time, that is, as the flow rate changes, the measurement accuracy can be dynamically adjusted by measuring the frequency of the AC voltage. In addition, the device does not require external power supply, can automatically adjust the measurement accuracy within a large range, is not subject to external electromagnetic interference, is simple to adjust, consumes less materials in manufacturing, and has a small overall size.

[0072] The embodiment of the present invention further provides a flow metering method, which is implemented based on the flow metering device described in the above embodiment, and includes:

[0073] Acquiring an alternating current voltage output by a power generation mechanism, and calculating a voltage frequency of the alternating current voltage;

[0074] Performing a fast Fourier transform on the voltage frequency to obtain a fundamental frequency;

[0075] According to the fundamental frequency and a preset flow coefficient database, a flow coefficient corresponding to the fundamental frequency is obtained;

[0076] Calculating the product of the sampling period and the flow coefficient to obtain the instantaneous flow in each sampling period;

[0077] All the instantaneous flow rates are accumulated to obtain the fluid flow rate.

[0078] It should be noted that a flow metering method provided in an embodiment of the present invention corresponds to all implementation steps of a flow metering device in the above embodiment, and the working principles and beneficial effects of the two correspond one to one, so they will not be described in detail.

[0079] The embodiment of the present invention further provides a terminal device. The terminal device includes: a processor, a memory, and a computer program stored in the memory and executable on the processor, such as a flow metering program. When the processor executes the computer program, the steps in the above-mentioned flow metering method embodiments are implemented. Alternatively, when the processor executes the computer program, the functions of each module / unit in the above-mentioned device embodiments are implemented, such as a data processing module.

[0080] Exemplarily, the computer program may be divided into one or more modules / units, which are stored in the memory and executed by the processor to implement the present invention. The one or more modules / units may be a series of computer program instruction segments capable of implementing specific functions, which are used to describe the execution process of the computer program in the terminal device.

[0081] The terminal device may be a computing device such as a desktop computer, a notebook, a PDA, and a smart tablet. The terminal device may include, but is not limited to, a processor and a memory. Those skilled in the art will appreciate that the above components are merely examples of terminal devices and do not constitute a limitation on the terminal device. The terminal device may include more or fewer components than the above components, or may combine certain components, or different components. For example, the terminal device may also include input and output devices, network access devices, buses, etc.

[0082] The processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc. The processor is the control center of the terminal device, and uses various interfaces and lines to connect various parts of the entire terminal device.

[0083] The memory can be used to store the computer program and / or module, and the processor realizes various functions of the terminal device by running or executing the computer program and / or module stored in the memory, and calling the data stored in the memory. The memory can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, an application required for at least one function (such as a sound playback function, an image playback function, etc.), etc.; the data storage area can store data created according to the use of the mobile phone (such as audio data, a phone book, etc.), etc. In addition, the memory can include a high-speed random access memory, and can also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0084] Wherein, if the module / unit integrated in the terminal device is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on such an understanding, the present invention implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Wherein, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electric carrier signal, telecommunication signal and software distribution medium. It should be noted that the content contained in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electric carrier signals and telecommunication signals.

[0085] It should be noted that the device embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. In addition, in the accompanying drawings of the device embodiments provided by the present invention, the connection relationship between the modules indicates that there is a communication connection between them, which may be specifically implemented as one or more communication buses or signal lines. A person of ordinary skill in the art may understand and implement it without paying any creative effort.

[0086] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. It is particularly pointed out that for those skilled in the art, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. A flow metering device, characterized in that: It comprises a shell, a power generation mechanism, a data acquisition module and a data processing module, wherein the shell is connected to an inlet pipe, the power generation mechanism is arranged in the shell, and the power generation mechanism is used to detect the fluid flow of the inlet pipe and output an AC voltage; the data acquisition module is communicatively connected with the data processing module, and the data acquisition module is used to obtain the AC voltage according to a preset sampling period and send it to the data processing module; The data processing module is configured as follows: receiving the AC voltage and calculating a voltage frequency of the AC voltage; Performing a fast Fourier transform on the voltage frequency to obtain a fundamental frequency; According to the fundamental frequency and a preset flow coefficient database, a flow coefficient corresponding to the fundamental frequency is obtained; Calculating the product of the sampling period and the flow coefficient to obtain the instantaneous flow in each sampling period; Accumulating all the instantaneous flow rates to obtain the fluid flow rate; The flow coefficient database includes a fundamental frequency-flow coefficient relationship curve; The configuration process of the fundamental frequency-discharge coefficient relationship curve includes: According to the preset m flow gears, m measurement voltage frequencies are obtained, where m is a positive integer greater than 1; Performing fast Fourier transform on the m measured voltage frequencies respectively to obtain m measured fundamental wave frequencies; Calculating according to the m measurement fundamental frequencies, the number of non-zero values ​​among the m measurement fundamental frequencies and a preset total flow rate, to obtain m measurement flow coefficients corresponding to the measurement fundamental frequencies; Fitting is performed based on the m measured fundamental frequencies and the m measured flow coefficients to obtain a fundamental frequency-flow coefficient relationship curve.

2. The flow metering device according to claim 1, characterized in that: The power generation mechanism includes a stator and a rotor. The rotor is used to rotate with the fluid. The rotation axis of the rotor is perpendicular to the flow direction of the fluid. The data input end of the data acquisition module is connected to the output end of the stator.

3. The flow metering device according to claim 2, characterized in that: The power generation mechanism also includes a rectifier module and an energy storage module, the input end of the rectifier module is connected to the output end of the stator, the output end of the rectifier module is connected to the input end of the energy storage module, and the output end of the energy storage module is connected to the power input end of the data acquisition module.

4. The flow metering device according to claim 1, characterized in that: The flow rate gear is positively correlated with the cross-sectional area for fluid circulation in the inlet pipe, and the flow rate gear at least includes a maximum flow rate gear and a minimum flow rate gear.

5. The flow metering device according to claim 1, characterized in that: The device further comprises a display module, which is in communication connection with the data processing module and is used for displaying the fluid flow rate and the working state of the flow metering device.

6. A flow metering method, implemented based on the flow metering device according to any one of claims 1 to 5, characterized in that: The method comprises: Acquiring an alternating current voltage output by a power generation mechanism, and calculating a voltage frequency of the alternating current voltage; Performing a fast Fourier transform on the voltage frequency to obtain a fundamental frequency; According to the fundamental frequency and a preset flow coefficient database, a flow coefficient corresponding to the fundamental frequency is obtained; Calculating the product of the sampling period and the flow coefficient to obtain the instantaneous flow in each sampling period; All the instantaneous flow rates are accumulated to obtain the fluid flow rate.

7. A computer-readable storage medium, characterized in that: The computer-readable storage medium includes a stored computer program, wherein when the computer program is executed, the device where the computer-readable storage medium is located is controlled to execute the flow metering method according to claim 6.

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