NB remote ultrasonic gas meter internal metering flow channel calibration method, terminal, and system

Abstract

The present application relates to a method, terminal, and system for calibrating the metering flow channel in an NB remote ultrasonic gas meter, wherein the method includes: obtaining a plurality of first ultrasonic signal data within a first time period under zero flow conditions; preliminarily determining whether the gas meter has a zero bias problem based on the first ultrasonic signal data; when the gas meter has a zero bias problem, obtaining a plurality of second ultrasonic signal data within a second time period to determine whether the time deviation of the gas meter caused by the zero bias problem is a fixed value; when the time deviation is a fixed value, calibrating the gas meter based on the first offset curve and the second offset curve to obtain a calibration result. The gas meter of the present application can still obtain accurate flow values when a small flow of gas is circulating, effectively improving the problem of low gas meter measurement accuracy caused by relying solely on the zero flow time deviation measured under a standard test environment.

Description

Technical Field

[0001] The present application relates to the technical field of flow zero bias correction, and in particular to a method, terminal, and system for correcting a metering flow channel in an NB remote ultrasonic gas meter. Background Art

[0002] In modern gas metering systems, NB remote ultrasonic gas meters are gradually becoming mainstream equipment in the gas metering field due to their significant advantages such as high precision, no mechanical wear, and remote data transmission. NB remote ultrasonic gas meters rely on NB-IoT Internet of Things technology to achieve remote and stable data transmission, and at the same time use the propagation time difference of ultrasonic waves in gas to accurately measure gas flow rate and thus accurately calculate gas flow.

[0003] Currently, the time difference method is the main way for NB remote ultrasonic gas meters to measure gas flow in the flow channel. Its core is to accurately calculate the gas flow rate through the upstream and downstream flight time of the ultrasonic wave in the flow channel. In an ideal static zero-flow state, in theory, the upstream and downstream flight times should be completely equal. However, in real scenarios, even if the user does not use gas, a certain amount of gas or other gases will often remain in the flow channel, and it is not in an absolute zero-flow state. This situation will cause deviations in the upstream and downstream flight times of the ultrasonic wave, which will cause the gas meter to still measure a smaller flow value at zero flow. This is the so-called zero-point offset problem.

[0004] In response to the above-mentioned zero bias problem, the traditional solution is usually to conduct a zero-flow experiment in a standard test environment before the gas meter leaves the factory, thereby obtaining a zero-flow time deviation value; and when the gas meter subsequently calculates the upstream and downstream flight time difference, the zero bias is corrected by directly subtracting the zero-flow time deviation; however, due to the large difference between the actual application scenario of the gas meter and the standard test environment, the gas meter cannot simply rely on the zero-flow time deviation determined in the standard test environment at the time of leaving the factory to achieve accurate measurement of small-flow gas in other working environments such as temperature, pressure, and non-parallel installation of the internal transducer of the gas meter; therefore, relying solely on the zero-flow time deviation measured at the factory for correction in non-standard environment scenarios will result in low actual measurement accuracy of the gas meter, which is far from meeting the high requirements for gas meter measurement accuracy in actual use. Summary of the Invention

[0005] In order to improve the problem of low gas meter measurement accuracy caused by relying solely on the zero flow time deviation measured under the standard test environment at the factory for correction, the present application provides a NB remote ultrasonic gas meter internal metering flow channel correction method, terminal, and system.

[0006] In a first aspect, the present application provides a method for calibrating a metering flow channel in an NB remote ultrasonic gas meter, which adopts the following technical solution:

[0007] A method for calibrating a metering flow channel in a NB remote ultrasonic gas meter is applied to an ultrasonic gas meter. The ultrasonic gas meter includes a flow sensor for detecting and obtaining ultrasonic signal data of an ultrasonic wave in a flow channel to be measured. Each ultrasonic signal data includes a set of upstream flight time and downstream flight time, including:

[0008] Under zero flow conditions, obtaining a plurality of first ultrasonic signal data within a preset first time period;

[0009] Preliminarily determine whether the gas meter has a zero offset problem based on the first ultrasonic signal data;

[0010] When the gas meter has a zero bias problem, obtaining a plurality of second ultrasonic signal data within a preset second time period;

[0011] obtaining a first offset curve based on the first ultrasonic signal data, and obtaining a second offset curve based on the second ultrasonic signal data, wherein the first offset curve and the second offset curve are used to reflect the continuous change of the difference between the upstream flight time and the downstream flight time within a corresponding time period;

[0012] Obtaining an initial zero bias function according to the first offset curve and the second offset curve, wherein the initial zero bias function is used to calculate an approximate zero bias value of the gas meter in the first time period and the second time period;

[0013] Determine whether the time deviation of the gas meter caused by the zero offset problem is a fixed value according to the approximate zero offset value;

[0014] When the time offset is a fixed value, obtaining a correction zero offset value based on the first offset curve and the second offset curve;

[0015] The difference between each set of upstream flight time and downstream flight time is corrected according to the correction zero bias value to obtain a correction result.

[0016] By adopting the above technical solution, under zero flow conditions, a number of first ultrasonic signal data within a first time period are first obtained to make a preliminary judgment on whether the gas meter has a zero bias problem. This preliminary detection mechanism provides a prerequisite for subsequent precise calibration, avoids unnecessary complex processing of gas meters without zero bias problems, and can also promptly detect gas meters with zero bias problems, taking a critical first step towards improving measurement accuracy.

[0017] After determining that the gas meter has a zero-bias problem, further data from several second ultrasonic signals within a second time period is obtained and combined with the first ultrasonic signal data to determine whether the time deviation caused by the zero-bias problem is a fixed value. This step breaks through the limitation of the traditional method of relying solely on a single zero-flow test at the factory. In this way, it can accurately determine which subsequent correction method should be selected;

[0018] When the time deviation is determined to be a fixed value, the gas meter is calibrated using the first ultrasonic signal data and the second ultrasonic signal data, fully considering the complexity of the gas meter in actual use scenarios, and taking into account a series of interference factors that may affect the time deviation, such as temperature, pressure, and transducer installation conditions. A fixed time deviation obtained through comprehensive analysis and processing of multiple groups of data is used to uniformly mark the impact of these interference factors. This avoids the situation where the single zero flow time deviation obtained under a standard test environment is still used for correction when there are multiple factors acting together in the time deviation of the gas meter, resulting in low measurement accuracy of the corrected gas meter. This comprehensively improves the measurement accuracy of the gas meter in actual use, while meeting the high requirements for gas meter measurement accuracy under small flow conditions, and overcomes the problem of low measurement accuracy of traditional calibration methods in non-standard environments.

[0019] In a specific possible implementation scheme, the first time period consists of a plurality of initial acquisition cycles, each initial acquisition cycle in the first time period corresponds to a first ultrasonic signal data, and each first ultrasonic signal data specifically includes a set of a first upstream flight time and a first downstream flight time; and preliminarily determining whether the gas meter has a zero bias problem based on the first ultrasonic signal data includes:

[0020] calculating an average phase difference between each group of the first upstream flight time and the first downstream flight time;

[0021] If the average phase difference is zero, it is determined that the gas meter does not have a zero bias problem;

[0022] If the average phase difference exceeds the preset value fluctuation range, it is determined that the gas meter has an abnormal fault and an alarm is triggered;

[0023] If the average phase difference value is within the numerical fluctuation range, it is determined that the gas meter has a zero bias problem.

[0024] In a specific possible implementation scheme, the second time period consists of a plurality of initial acquisition cycles, each initial acquisition cycle in the second time period corresponds to a second ultrasonic signal data, and each second ultrasonic signal data specifically includes a set of second upstream flight time and second downstream flight time; obtaining a first offset curve based on the first ultrasonic signal data and obtaining a second offset curve based on the second ultrasonic signal data include:

[0025] determining a plurality of first target acquisition cycles corresponding to the first time period based on all of the first upstream flight times, and determining a plurality of second target acquisition cycles corresponding to the second time period based on all of the second upstream flight times;

[0026] Calculating a plurality of first time differences corresponding to each first target acquisition period based on the first upstream flight time and the first downstream flight time, and calculating a plurality of second time differences corresponding to each second target acquisition period based on the second upstream flight time and the second downstream flight time, wherein the first time difference represents a difference between a certain group of the first upstream flight time and the first downstream flight time within the first time period; and the second time difference represents a difference between a certain group of the second upstream flight time and the second downstream flight time within the second time period;

[0027] A first offset curve corresponding to the first time period is obtained based on all the first time differences, and a second offset curve corresponding to the second time period is obtained based on all the second time differences. The first offset curve is specifically used to reflect the continuous change of the first time difference within the first time period, and the second offset curve is specifically used to reflect the continuous change of the second time difference within the second time period.

[0028] In a specific implementation scheme, the initial zero bias function is used to obtain an approximate zero bias value corresponding to each initial acquisition period based on the first time difference and the second time difference, and the approximate zero bias value is used to represent the actual bias value of the gas meter in the initial acquisition period; the calculation formula of the initial zero bias function is as follows:

[0029] ;

[0030] in, represents the initial zero bias function; represents the first offset curve; represents the second offset curve;

[0031] The determining, based on the approximate zero offset value, whether the time deviation of the gas meter caused by the zero offset problem is a fixed value includes:

[0032] Calculating an average zero bias of the initial zero bias function in the first time period or the second time period, where the average zero bias is an average of all consecutive approximate zero bias values of the initial zero bias function in the first time period or the second time period;

[0033] Calculating the sum of the squared errors between the approximate zero bias values corresponding to all the initial acquisition cycles in the first time period or the second time period and the average zero bias;

[0034] If the sum of the variances is less than or equal to a preset variance sum threshold, it is determined that the time deviation corresponding to the gas meter is a fixed value;

[0035] If the sum of the variances is greater than the sum of the variances threshold, it is determined that the time deviation corresponding to the gas meter is not a fixed value.

[0036] In a specific implementation manner, determining a plurality of first target acquisition cycles corresponding to the first time period based on all the first upstream flight times includes:

[0037] determining a reference upstream flight time corresponding to the first time period from among all the first upstream flight times;

[0038] Calculating a first phase difference between the reference upstream flight time and all other first upstream flight times;

[0039] If the first phase difference is less than or equal to a preset phase difference threshold, the initial acquisition period corresponding to the first phase difference is used as a first target acquisition period.

[0040] In a second aspect, the present application provides a smart terminal, which adopts the following technical solution:

[0041] A smart terminal includes a memory and a processor, wherein the memory stores at least one instruction, at least one program, code set, or instruction set, and the at least one instruction, at least one program, code set, or instruction set is loaded and executed by the processor to implement the metering flow channel calibration method in the NB remote ultrasonic gas meter as described in the first aspect.

[0042] In a third aspect, the present application provides a NB remote ultrasonic gas meter internal metering flow channel calibration system, which adopts the following technical solutions:

[0043] A NB remote ultrasonic gas meter internal metering flow channel calibration system, comprising:

[0044] A temperature sensor is used to measure the gas temperature in the flow channel to be measured;

[0045] A pressure sensor is used to measure the gas pressure in the flow channel to be measured;

[0046] The smart terminal as described in the second aspect is communicatively connected to the flow sensor, the temperature sensor and the pressure sensor, and is used to calibrate the ultrasonic gas meter according to the gas temperature, the gas pressure, the upstream flight time and the downstream flight time to obtain a calibration result.

[0047] In a fourth aspect, the present application provides a computer-readable storage medium, which adopts the following technical solution:

[0048] A computer-readable storage medium, wherein the readable storage medium stores at least one instruction, at least one program, code set, or instruction set, wherein the at least one instruction, at least one program, code set, or instruction set is loaded and executed by a processor to implement the metering flow channel calibration method in an NB remote ultrasonic gas meter as described in the first aspect.

[0049] In summary, this application includes at least one of the following beneficial technical effects:

[0050] 1. This application provides a more comprehensive and accurate solution for detecting and correcting zero-bias problems in ultrasonic gas meters. Under zero-flow conditions, a simple first ultrasonic signal data set is used to preliminarily determine whether the gas meter has a zero-bias problem. If a zero-bias problem exists, a second ultrasonic signal data set is added for comparative analysis of the two data sets, avoiding blind operation and effectively improving correction efficiency.

[0051] 2. When the time offset is fixed, a zero offset value is derived based on the first and second offset curves, and the difference between the upstream and downstream flight times of the flow sensor is accurately corrected. This correction method effectively addresses the different time offsets caused by zero offset issues for each gas meter. This method significantly improves measurement accuracy, particularly in low-flow gas flow conditions, bringing gas meter results closer to the true value in complex real-world environments. This method overcomes the low measurement accuracy often associated with relying solely on the zero-flow time offset measured under standard test conditions at the factory.

[0052] 3. This application overcomes the problem of inconsistent calibration standards due to differences between actual application scenarios (such as non-parallel installation of transducers, different flow channel structures, different temperatures, different pressures, etc.) and standard test environments. It enables each gas meter to be accurately calibrated according to its own situation while eliminating most possible interference factors (determining whether the time deviation is a fixed value), thereby achieving high-precision measurement of ultrasonic gas meters in various complex working environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1This is a structural diagram of a metering flow channel calibration system in a NB remote ultrasonic gas meter according to an embodiment of the present application.

[0054] Figure 2 It is a flow chart of a method for calibrating a metering flow channel in a NB remote ultrasonic gas meter according to another embodiment of the present application.

[0055] Figure 3 2 is a schematic diagram of a first offset curve and a second offset curve according to another embodiment of the present application.

[0056] Figure 4 Schematic diagram of an initial zero bias function according to another embodiment of the present application.

[0057] Figure 5 This is a flowchart of steps S700-S900 after determining whether the time deviation corresponding to the gas meter is a fixed value in S600 according to another embodiment of the present application. DETAILED DESCRIPTION

[0058] In order to make the objectives, technical solutions and advantages of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.

[0059] The following is a further detailed description of the embodiments of the NB remote ultrasonic gas meter internal metering flow channel calibration method, terminal, and system of the present application in conjunction with all the drawings in the specification.

[0060] Reference Figure 1One embodiment of the present application discloses a metering flow channel calibration system for an NB remote ultrasonic gas meter. The zero bias automatic calibration system is applied to an ultrasonic gas meter. The ultrasonic gas meter includes a first transducer, a second transducer, a flow sensor, and a display. The first transducer and the second transducer are respectively installed on opposite sides of the flow channel to be measured. The second transducer is used to emit an ultrasonic wave along the flow direction of the gas (the time from the emission of the ultrasonic wave to the reception by the first transducer corresponds to the downstream flight time described below), and the first transducer is used to emit an ultrasonic wave against the flow direction of the gas (the time from the emission of the ultrasonic wave to the reception by the second transducer corresponds to the upstream flight time described below); the flow sensor is used to detect the ultrasonic wave. Several groups of ultrasonic signal data of the signal in the flow channel to be measured, each group of ultrasonic signal data includes an upstream flight time and a downstream flight time; the ultrasonic gas meter in this embodiment takes the NB remote ultrasonic gas meter as an example. The NB remote ultrasonic gas meter has a powerful data storage function, which can organize and record the upstream flight time, downstream flight time and various test parameters (including gas temperature, gas pressure, etc.) measured by the flow sensor during each complete ultrasonic transmission and reception process, to provide data support for the smart terminal described below for realizing zero bias correction, thereby continuously ensuring the measurement accuracy of the NB remote ultrasonic gas meter. This is an existing technology and will not be repeated here.

[0061] Reference Figure 1 A system for correcting the flow passage in an NB remote ultrasonic gas meter includes a temperature sensor, a pressure sensor, and a smart terminal. The temperature sensor is used to measure the gas temperature at the inlet and outlet of the flow passage to be measured. The pressure sensor is used to measure the gas pressure at the inlet and outlet of the flow passage to be measured. The flow sensor is also used to send each set of measured upstream flight time and downstream flight time to the smart terminal in real time. The smart terminal is used to automatically correct the zero bias of the ultrasonic gas meter flow passage based on the upstream flight time, downstream flight time, temperature parameters, and pressure parameters. The smart terminal is communicatively connected to a display in the ultrasonic gas meter, which is mounted on the outer wall of the flow passage to be measured and is used to display the flow rate corrected by the smart terminal. The smart terminal includes a processor and a memory, the memory being used to store at least one instruction, at least one program, code set, or instruction set. When the processor runs the at least one instruction, at least one program, code set, or instruction set, it executes the following steps of a method for correcting the flow passage in an NB remote ultrasonic gas meter.

[0062] The following describes in detail the implementation of a NB remote ultrasonic gas meter internal metering flow channel calibration method in conjunction with the above-mentioned NB remote ultrasonic gas meter internal metering flow channel calibration system:

[0063] Reference Figure 2Another embodiment of the present application provides a method for calibrating a metering flow channel in a NB remote ultrasonic gas meter, comprising:

[0064] S100, acquiring a plurality of first ultrasonic signal data within a preset first time period under a zero flow condition;

[0065] Among them, the first time period is composed of several initial acquisition cycles. To facilitate the detailed explanation of the subsequent calculation process, the duration of the first time period in this embodiment is taken as 1 hour. The amount of first ultrasonic signal data in the first time period is determined by the acquisition frequency of the transducer. In this embodiment, the two transducers in the flow channel to be measured have an initial acquisition cycle of every 10 minutes. For example, the processor will obtain 6 first ultrasonic signal data within one hour (the amount of first ultrasonic signal data obtained during the actual calibration process will be more; in addition, in each initial acquisition cycle, a complete cross-transmission and reception process of the ultrasonic signal includes: first, the first transducer sends a signal A, then the second transducer sends a signal B in response to the signal A after receiving the signal A sent by the first transducer, and finally, the first transducer receives the signal B sent by the second transducer); the first ultrasonic signal data is used to calculate the flow rate of the gas in the flow channel to be measured, and each initial acquisition cycle in the first time period corresponds to a first ultrasonic signal data.

[0066] S200, preliminarily determining whether the gas meter has a zero offset problem based on the first ultrasonic signal data;

[0067] The first ultrasonic signal data includes a first upstream flight time corresponding to the first transducer and a first downstream flight time corresponding to the second transducer during an initial acquisition period within a first time period; the first upstream flight time represents the flight time of the ultrasonic signal from the first transducer to the second transducer, and the first downstream flight time represents the flight time of the ultrasonic signal from the second transducer to the first transducer; specifically, S200 includes:

[0068] S210, calculating an average phase difference between each group of first upstream flight time and first downstream flight time in the first time period;

[0069] Among them, the average phase difference value is the average value of the difference between each group of first upstream flight time and first downstream flight time corresponding to each initial acquisition cycle. The average phase difference value is used to reflect the overall difference in the propagation characteristics of the ultrasonic signal between the first transducer and the second transducer in the first time period. It can be used as a preliminary indicator to evaluate whether the gas meter has potential zero bias problems or other abnormal conditions.

[0070] S220: If the average phase difference value is zero, it is determined that the gas meter does not have a zero bias problem.

[0071] S230, if the average phase difference value exceeds the preset value fluctuation range, it is determined that the gas meter has an abnormal fault, and an alarm is triggered;

[0072] The numerical fluctuation range is related to the timing accuracy of the ultrasonic sensor in the gas meter. This numerical fluctuation range mainly takes into account the sensor's own errors and the possible differences in ultrasonic signal transmission time under slight environmental fluctuations. This numerical fluctuation range can be manually input before the zero-bias calibration of the gas meter begins, or it can be automatically matched by the smart terminal according to the gas meter model to be calibrated. In this embodiment, under normal operation and zero flow, the numerical fluctuation range is [-100ns, 100ns] as an example. For sensors with higher accuracy requirements, the corresponding numerical fluctuation range can reach [-10ns, 10ns].

[0073] When the average phase difference exceeds the corresponding numerical fluctuation range, it indicates that there are significant factors affecting the propagation time of the ultrasonic wave. It may be a serious deviation in the installation angles of the two transducers (including excessive torsion, pitch angle, and roll angle), which makes the propagation path length of the ultrasonic wave in the flow channel to be measured very different in the downstream and upstream directions. There may also be serious blockage, foreign matter or local deformation inside the flow channel to be measured, which changes the propagation path and speed of the ultrasonic wave. There may also be strong electromagnetic interference near the flow channel to be measured or a mechanical failure of the transducer (such as abnormal transmission and receiving functions). The above factors often cannot be reduced by simple data correction, so a direct alarm is issued to notify relevant technical personnel to perform maintenance.

[0074] S240: If the average phase difference value is within the numerical fluctuation range, it is determined that the gas meter has a zero bias problem.

[0075] S300, when the gas meter has a zero offset problem, obtaining a plurality of second ultrasonic signal data within a preset second time period;

[0076] The second time period is similar to the first time period in S100, and the second time period is equal to the first time period in length. Similarly, the second time period is composed of a plurality of initial acquisition cycles. The second ultrasonic signal is also used to calculate the flow rate of the gas in the flow channel to be measured, and each initial acquisition cycle in the second time period corresponds to a second ultrasonic signal data. The second ultrasonic signal data includes a first upstream flight time corresponding to the first transducer and a first downstream flight time corresponding to the second transducer during a certain initial acquisition cycle in the second time period. The second upstream flight time represents the flight time of the ultrasonic signal from the first transducer to the second transducer, and the second downstream flight time represents the flight time of the ultrasonic signal from the second transducer to the first transducer.

[0077] The first ultrasonic signal data of this embodiment is shown in Table 1 below, and the second ultrasonic signal data is shown in Table 2 below:

[0078] Table 1 The first period All first ultrasonic signal data tables within

[0079]

[0080] Table 2 The second time period All second ultrasonic signal data tables within

[0081]

[0082] It should be noted that, in terms of signal processing, since the various component parameters of the signal processing circuit in the ultrasonic gas meter can be considered relatively stable during the first and second time periods, this embodiment does not consider the impact of circuit component aging and performance fluctuations (such as changes in capacitor leakage rate and amplifier gain drift) on the ultrasonic signal flight time measurement. Other interference factors in the signal transmission process, such as the intensity and frequency characteristics of electromagnetic interference, also remain basically consistent during the first and second time periods. Therefore, this embodiment also does not take these interference factors into account.

[0083] From an environmental perspective, within the selected first and second time periods, factors such as ambient temperature, pressure, and gas composition (humidity, impurity content) in the flow channel may fluctuate due to factors such as air flow and equipment heat dissipation, resulting in deviations in the measured first upstream flight time, second upstream flight time, first downstream flight time, and second downstream flight time under zero flow conditions, resulting in a lower accuracy of the final time deviation, which in turn affects the correction effect of the present application; therefore, in order to ensure as much as possible that the effects of various environmental factors on the ultrasonic propagation speed remain relatively stable in the zero flow experiment, this embodiment adopts the following step S410 after step S300 to screen out the first (second) target acquisition period that can be used as effective comparison data in the zero flow experiment from all first (second) ultrasonic signal data.

[0084] S410, determining a plurality of first target acquisition cycles corresponding to a first time period based on all first upstream flight times, and determining a plurality of second target acquisition cycles corresponding to a second time period based on all second upstream flight times;

[0085] Among them, the first upstream flight times corresponding to all first target acquisition periods have a small difference in value and can be regarded as the flight times of ultrasonic signals measured under substantially the same environmental factors; similarly, the second upstream flight times corresponding to the second target acquisition period also have a small difference in value; specifically, since the principles of the determination methods of the first target acquisition period and the second target acquisition period are the same, this embodiment takes the first target acquisition period as an example for detailed description, and in S410, determining the plurality of first target acquisition periods corresponding to the first time period based on all the first upstream flight times includes:

[0086] S411, determining a reference upstream flight time corresponding to the first time period from all first upstream flight times;

[0087] The reference upstream flight time may be any one of all first upstream flight times. In this embodiment, the reference upstream flight time takes the first upstream flight time corresponding to the first initial acquisition cycle as an example.

[0088] S412, determining a number of first target acquisition cycles corresponding to the first time period according to the reference upstream flight time;

[0089] Specifically, S412 includes:

[0090] S4121, calculating a first phase difference between the reference upstream flight time and all other first upstream flight times;

[0091] The first phase difference between each first upstream flight time and the reference upstream flight time is calculated as follows:

[0092] ;

[0093] in, Indicates the a first phase difference between a first upstream flight time corresponding to an initial acquisition cycle and a reference upstream flight time; represents the reference upstream flight time corresponding to the first time period; Indicates the The first upstream flight time corresponding to the initial acquisition cycle.

[0094] S4122: If the first phase difference is less than or equal to a preset phase difference threshold, the initial acquisition period corresponding to the first phase difference is used as a first target acquisition period;

[0095] Among them, the phase difference threshold of this embodiment takes 0.1 as an example; by screening the initial acquisition cycle in step S4122, the first target acquisition cycle set (including all first target acquisition cycles) can be quickly determined within the first time period when all influencing factors remain relatively consistent. This helps to eliminate data deviations caused by various unstable interference factors, thereby providing a stable and reliable data basis for the accurate calculation of subsequent time deviations.

[0096] It should be noted that the method for determining the several second target acquisition cycles corresponding to the second time period in S410 is similar to steps S411-S412 and will not be repeated here. Generally speaking, to ensure the rigor of the data, the number of the first / second target acquisition cycles needs to be maintained at 3 or more. If the number of the first / second target acquisition cycles finally determined in step S410 is less than 3 (i.e., does not meet the minimum requirement), the corresponding first / second time period is extended separately to collect more first ultrasonic signal data (second ultrasonic signal data) in S100 (S300). Each time an initial acquisition cycle is added, step S410 is used to determine whether the newly added initial acquisition cycle can be used as the target acquisition cycle. This process is repeated until the number of the corresponding first / second target acquisition cycles meets the minimum requirement.

[0097] In addition, to ensure the accuracy of the determination of whether the time deviation is a fixed value in the subsequent step S600, the reference upstream flight time selected in the first time period must not be the same as the reference upstream flight time selected in the second time period (if the reference upstream flight time selected in the second time period is the same as the reference upstream flight time in the first time period, the first upstream flight time corresponding to the next initial collection period is selected as the reference upstream flight time corresponding to the second time period, and so on, until the above-mentioned limiting conditions are met). For ease of understanding, the first target collection period and the second target collection period of this embodiment are shown in Tables 3 and 4 below, respectively:

[0098] Table 3 The first target acquisition cycle set table ( )

[0099]

[0100] Table 4 Second target acquisition cycle set table ( )

[0101]

[0102] S400, obtaining a first offset curve according to the first ultrasonic signal data, and obtaining a second offset curve according to the second ultrasonic signal data;

[0103] Specifically, S400 includes:

[0104] S420, calculating a plurality of first time differences corresponding to each first target acquisition period based on the first upstream flight time and the first downstream flight time, and calculating a plurality of second time differences corresponding to each second target acquisition period based on the second upstream flight time and the second downstream flight time;

[0105] The first time difference refers to the difference between the first upstream flight time and the first downstream flight time corresponding to a first target acquisition period, and the second time difference refers to the difference between the second upstream flight time and the second downstream flight time corresponding to a second target acquisition period. Specifically, the calculation formulas for the first time difference and the second time difference are as follows:

[0106] ;

[0107] ;

[0108] in, Indicates the A first time difference corresponding to a first target acquisition period; Indicates the The first upstream flight time corresponding to the first target acquisition cycle; Indicates the A first downstream flight time corresponding to a first target acquisition cycle; Indicates the total number of first target acquisition cycles; Indicates the a second time difference corresponding to a second target acquisition period; Indicates the a second upstream flight time corresponding to a second target acquisition cycle; Indicates the a second downstream flight time corresponding to a second target acquisition cycle; Indicates the total number of second target acquisition cycles.

[0109] S430, obtaining a first offset curve corresponding to the first time period according to all the first time differences, and obtaining a second offset curve corresponding to the second time period according to all the second time differences;

[0110] Among them, reference Figure 3The first offset curve and the second offset curve are used to reflect the continuous change of the difference between the upstream flight time and the downstream flight time in the corresponding time period. Specifically, the first offset curve is used to reflect the continuous change of the difference between each group of first upstream flight time and first downstream flight time (i.e., the first time difference) in the first time period; the second offset curve is used to reflect the continuous change of the difference between each group of second upstream flight time and second downstream flight time (i.e., the second time difference) in the second time period. Specifically, the first / second offset curves of this embodiment are calculated based on the least squares method of linear fitting. The calculation formula of the first offset curve is as follows:

[0111] ;

[0112] ;

[0113] ;

[0114] ;

[0115] in, Both are first offset curves The coefficient of Represents the first offset curve Previous continuous time point The corresponding first time difference; Indicates the first time period The discrete time points corresponding to the first time difference; Indicates the total number of first target acquisition cycles; represents the total number of initial collection cycles included in the first time period; Indicates the The first target acquisition cycle corresponds to the first Initial collection cycle; Indicates the first time period Total duration;

[0116] The calculation formula of the second offset curve is as follows:

[0117] ;

[0118] ;

[0119] ;

[0120] ;

[0121] in, Both are second offset curves The coefficient of Represents the second offset curve Previous continuous time point the corresponding second time difference; Indicates the second time period The discrete time points corresponding to the second time difference; Indicates the total number of second target acquisition cycles; Indicates the total number of initial collection cycles included in the second time period, ; Indicates the The second target acquisition cycle corresponds to the first Initial collection cycle; Indicates the second time period The total duration of .

[0122] S500, obtaining an initial zero bias function according to the first offset curve and the second offset curve;

[0123] The initial zero bias function is used to calculate the approximate zero bias value of the gas meter in the first time period and the second time period. The initial zero bias function is specifically used to calculate the approximate zero bias value of the gas meter corresponding to each initial acquisition cycle in the first time period (second time period) based on the first time difference (second time difference). Specifically, the initial zero bias function is as follows:

[0124] ;

[0125] in, represents the initial zero bias function; represents the first offset curve; represents the second offset curve.

[0126] S600: determining whether the time deviation of the gas meter caused by the zero offset problem is a fixed value based on the approximate zero offset value;

[0127] Among them, reference Figure 4 The time deviation is used to reflect the zero offset problem of the gas meter. Specifically, S600 includes:

[0128] S610, calculating the average zero bias of the initial zero bias function in the first time period or the second time period;

[0129] Among them, the average zero bias is the first time period or the second time period Internal initial bias function The average value of all the approximate zero bias values on the continuous θ is given by:

[0130] ;

[0131] in, represents the initial bias function In the interval The average zero bias in .

[0132] S620, calculating the sum of the squared errors between the approximate zero bias values corresponding to all initial acquisition cycles in the first time period or the second time period and the average zero bias;

[0133] Among them, the initial acquisition period in the first time period is the same as the initial acquisition period in the second time period. Therefore, in this embodiment, one of the above two (all initial acquisition periods in the first / second time period) can be selected to complete the calculation of the sum of variances; the sum of variances is used to reflect the initial zero bias function The actual fluctuation of the approximate zero bias value in the first time period or the second time period;

[0134] Specifically, if the approximate zero bias value in the first time period is used to calculate the sum of variances (in this case, s is taken as 0 in the calculation of the average zero bias), the formula for calculating the sum of variances is as follows:

[0135] ;

[0136] If the approximate zero bias value in the second time period is used to calculate the sum of variances (in this case, s is set to 1 in the calculation of the average zero bias), the formula for calculating the sum of variances is as follows:

[0137] ;

[0138] in, Indicates that the first time period and the The approximate zero bias value corresponding to the initial acquisition cycle; Indicates that the The approximate zero bias value corresponding to the initial acquisition cycle; represents the total number of initial collection cycles included in the first time period; represents the total number of initial collection cycles included in the second time period; represents the sum of the squared errors between the approximate zero bias values corresponding to each initial acquisition cycle and the average zero bias in the first time period; represents the sum of the squares of the approximate zero bias values corresponding to each initial acquisition cycle and the average zero bias in the second time period. In this embodiment, 、 Any one of them is taken as the final sum of variances; represents the mean bias.

[0139] S630, if the sum of the variances is less than or equal to a preset variance sum threshold, determining that the time deviation corresponding to the gas meter is a fixed value;

[0140] For high-precision gas meters, the variance and threshold values are generally between 0.01 and 0.05; for ordinary gas meters, the variance and threshold values are generally between 0.05 and 0.1. In this embodiment, the variance and threshold value are taken as 0.05 as an example.

[0141] S640: If the sum of the variances is greater than the sum of the variances threshold, it is determined that the time deviation corresponding to the gas meter is not a fixed value.

[0142] S700, when the time offset is a fixed value, obtaining a zero offset value for correction based on the first offset curve and the second offset curve;

[0143] Here, once the time deviation is determined to be a fixed value, it means that during the entire flow measurement process, the upstream flight time and downstream flight time of the ultrasonic signal in the same group in the gas meter always maintain a constant deviation, and this deviation is not affected by factors such as gas flow, environmental factors, and measurement time within a certain range. For example, due to the manufacturing tolerance of the sensor in gas meter A, the propagation time difference of the ultrasonic signal (the difference between the upstream flight time and the downstream flight time) in each measurement is always fixedly 5 microseconds longer. At this time, the zero bias of gas meter A can be compensated by using the fixed value of 5 microseconds as the correction zero bias value. The correction zero bias value is used to improve the zero bias problem of the gas meter. In this embodiment, taking the first time period as an example, the calculation formula of the correction zero bias value is as follows:

[0144] ;

[0145] in, Indicates that the first offset curve The approximate zero bias value corresponding to ; Indicates that the second offset curve The approximate zero bias value corresponding to ; Indicates the zero bias value for correction; Indicates the total number of initial acquisition cycles in the first time period. In this embodiment, all the above correction zero bias calculation formulas are Can also be replaced with .

[0146] S800, correcting the difference between each set of upstream flight time and downstream flight time according to the correction zero bias value to obtain a correction result;

[0147] Step S800 is performed once for each set of upstream flight time and downstream flight time sent by the flow sensor, and the correction result is the accurate flow value obtained after correction.

[0148] It should be noted that the S700 Positive and negative, when When it is a positive number, it means that there is a fixed positive deviation between the upstream flight time and the downstream flight time of the ultrasonic signal measured in the flow channel to be measured, which causes the actual flow value to be smaller than the flow detection value. This is because in the process of calculating the flow based on the ultrasonic flight time, a longer flight time difference (such as the difference between the upstream flight time and the downstream flight time in the time difference method) will make the calculated flow velocity smaller, and thus make the flow detection value larger. Therefore, at this time, it is necessary to subtract the correction zero bias value from the measured flight time difference to obtain a more accurate actual flow rate. Conversely, when the correction zero bias value is a negative number, the measured ultrasonic signal flight time is shorter than the actual flight time, and the actual flow value is larger than the flow detection value. At this time, it is necessary to add the absolute value of the correction zero bias value to the measured flight time difference to correct the flow detection value.

[0149] Specifically, the calculation formula for the accurate flow value (i.e., the calibration result) in S800 is as follows:

[0150] ;

[0151] in, Indicates the exact flow value; Indicates the length of the flow channel to be measured; It represents the upstream flight time of the ultrasonic signal measured by the flow sensor in the flow channel to be measured; It represents the downstream flight time of the ultrasonic signal measured by the flow sensor in the flow channel to be measured; Indicates the zero bias value for correction; Indicates the inclination angle between the ultrasonic signal transmission path and the flow channel to be measured, which is a preset value; Indicates the cross-sectional area of the flow channel to be measured, which is a preset value.

[0152] It should be noted that, when the time deviation is a fixed value, if the first transducer and the second transducer are not installed in parallel, the preset value in the above-mentioned S800 accurate flow value calculation formula is However, since the change in the tilt angle is a fixed value for the same ultrasonic gas meter, the offset error caused by the difference between the upstream flight time and the downstream flight time of the ultrasonic signal in the above situation is also a fixed value that can be calculated through steps S100-S800. Therefore, this application does not need to Situations where changes may occur are discussed individually.

[0153] S900, when the time deviation is not a fixed value, constructing a velocity-pressure field coupling function, and obtaining a correction result according to the velocity-pressure field coupling function;

[0154] The velocity-pressure field coupling function is used to solve the velocity field and pressure field that can affect each other during fluid flow through step-by-step iteration. Specifically, S900 includes:

[0155] S910, when the time deviation is not a fixed value, determining design variables and design parameters related to the gas flow rate in the flow channel to be measured;

[0156] Among them, the design variable is the gas flow rate in the flow channel to be metered, which has the greatest impact on the gas flow rate (when the gas demand is large, the gas flow rate in the flow channel to be metered is significantly accelerated); the design parameters include the gas temperature, gas pressure, gas density, and gas viscosity (i.e., the dynamic viscosity among the physical properties of gas) in the flow channel to be metered; the gas density and gas viscosity in this embodiment can be directly obtained by looking up the gas composition and the corresponding temperature based on a preset density and viscosity data table / simple interpolation formula for a specific gas component at different temperatures. Detailed information can be found in existing gas property databases / manuals and will not be repeated here.

[0157] It should be noted that the design parameters are usually parameters that are indirectly changed by changes in the gas flow rate in the flow channel to be metered, or that can directly affect the gas flow rate. The reasons for selecting the design parameters in this implementation are as follows:

[0158] In the actual fluid flow process, different gas components have different densities and dynamic viscosities. Changes in density and dynamic viscosity will cause the gas to exhibit different flow characteristics, because they will affect the resistance and energy loss of the gas flow, which in turn affects the velocity distribution and ultimately affects the time deviation. At the same time, temperature and pressure will also affect the gas density and viscosity. For example, in the flow channel to be measured, changes in temperature or pressure may cause uneven gas flow rate. This uneven flow state will indirectly change the gas density and viscosity, resulting in time deviation.

[0159] When studying the impact of these design parameters on flow calculation accuracy, it was found that when a single design parameter is changed (i.e., only that single variable is changed, while the other parameters remain the same as the standard values under a standard experimental environment), the overall flow calculation accuracy is not significantly affected. However, in actual practice, all design parameters often deviate from their corresponding standard values. In this case, the mutual influence of these design parameters can significantly increase the complexity of the flow calculation and significantly affect the overall flow calculation accuracy, potentially leading to large errors in the measurement results. Therefore, the design parameters of this embodiment include these variable factors, so that the impact of these variable factors is fully incorporated into the calculation of the correction zero bias.

[0160] S920, constructing a velocity-pressure field coupling function based on the design parameters and design variables;

[0161] The velocity-pressure field coupling function is as follows:

[0162] ;

[0163] in, Indicates gas viscosity; The velocity vector representing the gas transmitted in the flow channel to be measured, i.e. the gas flow velocity with directional attributes; Represents the gradient operator, which is a vector differential operator. That is the Laplace operator; Represents the pressure gradient, which is the driving force generated by the pressure difference of the fluid element and determines the direction of the fluid acceleration; the viscosity term represents the momentum diffusion caused by internal friction of the fluid.

[0164] It should be noted that since the method for correcting the flow conditions in the metering channel in this application is only applicable to horizontally laid channels, in this case, the pressure changes and flow rate changes in the metering channel are mainly caused by the pressure of the gas source and the flow demand of the gas-using equipment, and are not driven by volume forces such as gravity. Therefore, when applying the NS equation to solve the problem, the influence of volume forces on the solution results can be ignored.

[0165] S930, determining the boundary conditions and initial conditions of the velocity-pressure field coupling function;

[0166] The boundary conditions include the gas flow rate at the inlet and outlet of the flow channel to be measured (i.e., the design variable), the gas pressure measured by the pressure sensors at the inlet and outlet of the flow channel to be measured, and the gas temperature measured by the temperature sensor in the flow channel to be measured; the initial conditions include the gas flow rate, gas pressure, and gas temperature at the initial moment;

[0167] It should be noted that the gas flow rate at the inlet (outlet) of the flow channel to be measured can be directly obtained by the outlet (inlet) flow rate of upstream equipment such as a compressor and a gas storage tank (such as downstream equipment such as a gas furnace and a gas turbine); in this embodiment, the gas flow rate at the initial moment is 0, the gas pressure at the initial moment is the gas pressure measured by the pressure sensor at the inlet of the flow channel to be measured, and the gas temperature at the initial moment is the gas temperature measured by the temperature sensor in the flow channel to be measured.

[0168] S940, obtaining a correction result according to all boundary conditions, initial conditions, and velocity-pressure field coupling function;

[0169] The correction result is the accurate flow value recalculated by taking into account various design parameters. Specifically, in S940, all boundary conditions and initial conditions are first substituted into the velocity-pressure field coupling function to solve and obtain the velocity field and pressure field of the gas in the flow channel to be measured. The specific solution method can be achieved by the following method:

[0170] ① Finite Difference Method: Divide the gas flow channel in the flow channel to be metered into a grid, discretize the partial differential equations in the NS equations at the grid points, and obtain a set of algebraic equations. These algebraic equations are then solved numerically (iterative solution, such as Gauss-Seidel iteration, Jacobi iteration, etc.) to obtain the velocity and pressure values at each grid point, thereby obtaining the velocity field and pressure field in the flow channel to be metered.

[0171] Finite Volume Method: Divide the gas flow channel in the flow channel to be metered into a series of control volumes. Integrate the NS equations over the control volumes to obtain algebraic equations for the physical quantities at the center of the control volumes (i.e., convert the partial differential equations into algebraic equations in units of control volumes). Then, based on the boundary conditions and initial conditions, the integrated algebraic equations are iteratively solved to obtain physical quantities such as the average velocity and pressure in each control volume, thereby obtaining the velocity and pressure fields in the flow channel.

[0172] Finite element method: Discretize the gas flow channel in the flow channel to be metered into several units. Use interpolation functions to express the physical quantity in the unit as a function of the node value. Then, perform variational solution on the NS equation to obtain the algebraic equation about the node value. The subsequent processing steps of the algebraic equation are the same as those of the finite volume method mentioned above.

[0173] The above calculation methods are all existing technologies and will not be described in detail here.

[0174] It should be noted that through steps S910-S940, when the time deviation is not a fixed value, the present application can comprehensively consider the design variables, design parameters, boundary conditions and initial conditions through the constructed velocity-pressure field coupling function, so that the gas meter can meet the measurement requirements under complex working conditions such as different temperatures, pressures, gas composition changes and internal structure changes (such as transducer installation problems). By considering the interaction of multiple physical factors, accurate correction of the gas flow is achieved, effectively ensuring high-precision measurement of the gas meter in various actual usage scenarios.

[0175] Based on the same inventive concept mentioned above, an embodiment of the present application also discloses an intelligent terminal, which includes a memory and a processor, wherein the memory stores at least one instruction, at least one program, code set or instruction set, and the at least one instruction, at least one program, code set or instruction set is loaded and executed by the processor to implement a method for correcting the metering flow channel in an NB remote ultrasonic gas meter as provided in the above method embodiment.

[0176] Based on the same inventive concept mentioned above, an embodiment of the present application also discloses a computer-readable storage medium, which stores at least one instruction, at least one program, code set or instruction set. The at least one instruction, at least one program, code set or instruction set can be loaded and executed by a processor to implement a method for correcting the metering flow channel in a NB remote ultrasonic gas meter provided in the above method embodiment.

[0177] It should be understood that the term "several" in this document refers to two or more. "And / or" describes a relationship between related objects, indicating that three possible relationships exist. For example, "A and / or B" can mean: A exists alone, A and B exist simultaneously, or B exists alone. The character " / " generally indicates that the related objects are in an "or" relationship.

[0178] Those skilled in the art will appreciate that all or part of the steps of implementing the above embodiments may be accomplished by hardware, or may be accomplished by a program instructing the relevant hardware. The program may be stored in a computer-readable storage medium. The above-mentioned storage medium may include, for example, various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0179] The above description is merely an optional embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A method for calibrating a metering flow channel in a NB remote ultrasonic gas meter, applied to an ultrasonic gas meter comprising a flow sensor for detecting and obtaining ultrasonic signal data in a flow channel to be measured, characterized in that: include: Under zero flow conditions, obtaining a plurality of first ultrasonic signal data within a preset first time period, where the first time period consists of a plurality of initial acquisition cycles, each initial acquisition cycle within the first time period corresponds to one piece of first ultrasonic signal data, and each piece of the first ultrasonic signal data specifically includes a set of a first upstream flight time and a first downstream flight time; Preliminarily determine whether the gas meter has a zero offset problem based on the first ultrasonic signal data; When the gas meter has a zero bias problem, a plurality of second ultrasonic signal data within a preset second time period is obtained, where the second time period is composed of a plurality of initial acquisition cycles, each initial acquisition cycle within the second time period corresponds to one second ultrasonic signal data, and each second ultrasonic signal data specifically includes a set of second upstream flight time and second downstream flight time; obtaining a first offset curve based on the first ultrasonic signal data, and obtaining a second offset curve based on the second ultrasonic signal data, wherein the first offset curve and the second offset curve are used to reflect the continuous change of the difference between the upstream flight time and the downstream flight time within a corresponding time period; Obtaining an initial zero bias function according to the first offset curve and the second offset curve, wherein the initial zero bias function is used to calculate an approximate zero bias value of the gas meter in the first time period and the second time period; Determine whether the time deviation of the gas meter caused by the zero offset problem is a fixed value according to the approximate zero offset value; When the time offset is a fixed value, obtaining a correction zero offset value based on the first offset curve and the second offset curve; Correcting the difference between each set of upstream flight time and downstream flight time according to the correction zero bias value to obtain a correction result; The obtaining of a first offset curve according to the first ultrasonic signal data and obtaining a second offset curve according to the second ultrasonic signal data includes: determining a plurality of first target acquisition cycles corresponding to the first time period based on all of the first upstream flight times, and determining a plurality of second target acquisition cycles corresponding to the second time period based on all of the second upstream flight times; Calculating a plurality of first time differences corresponding to each first target acquisition period based on the first upstream flight time and the first downstream flight time, and calculating a plurality of second time differences corresponding to each second target acquisition period based on the second upstream flight time and the second downstream flight time, wherein the first time difference represents a difference between a certain group of the first upstream flight time and the first downstream flight time within the first time period; and the second time difference represents a difference between a certain group of the second upstream flight time and the second downstream flight time within the second time period; A first offset curve corresponding to the first time period is obtained based on all the first time differences, and a second offset curve corresponding to the second time period is obtained based on all the second time differences. The first offset curve is specifically used to reflect the continuous change of the first time difference within the first time period, and the second offset curve is specifically used to reflect the continuous change of the second time difference within the second time period.

2. The method for calibrating the internal metering flow channel of a NB remote ultrasonic gas meter according to claim 1 is characterized in that: The preliminarily determining whether the gas meter has a zero offset problem based on the first ultrasonic signal data includes: calculating an average phase difference between each group of the first upstream flight time and the first downstream flight time; If the average phase difference is zero, it is determined that the gas meter does not have a zero bias problem; If the average phase difference exceeds the preset value fluctuation range, it is determined that the gas meter has an abnormal fault and an alarm is triggered; If the average phase difference value is within the numerical fluctuation range, it is determined that the gas meter has a zero bias problem.

3. The method for calibrating the internal metering flow channel of a NB remote ultrasonic gas meter according to claim 1, characterized in that: The initial zero bias function is used to obtain an approximate zero bias value corresponding to each initial acquisition period based on the first time difference and the second time difference. The approximate zero bias value is used to represent the actual bias value of the gas meter in the initial acquisition period. The calculation formula of the initial zero bias function is as follows: ； in, represents the initial zero bias function; represents the first offset curve; represents the second offset curve; The determining, based on the approximate zero offset value, whether the time deviation of the gas meter caused by the zero offset problem is a fixed value includes: Calculating an average zero bias of the initial zero bias function in the first time period or the second time period, where the average zero bias is an average of all consecutive approximate zero bias values of the initial zero bias function in the first time period or the second time period; Calculating the sum of the squared errors between the approximate zero bias values corresponding to all the initial acquisition cycles in the first time period or the second time period and the average zero bias; If the sum of the variances is less than or equal to a preset variance sum threshold, it is determined that the time deviation corresponding to the gas meter is a fixed value; If the sum of the variances is greater than the sum of the variances threshold, it is determined that the time deviation corresponding to the gas meter is not a fixed value.

4. The method for calibrating the internal metering flow channel of a NB remote ultrasonic gas meter according to claim 3, characterized in that: The determining of a plurality of first target acquisition cycles corresponding to the first time period according to all the first upstream flight times includes: determining a reference upstream flight time corresponding to the first time period from among all the first upstream flight times; Calculating a first phase difference between the reference upstream flight time and all other first upstream flight times; If the first phase difference is less than or equal to a preset phase difference threshold, the initial acquisition period corresponding to the first phase difference is used as a first target acquisition period.

5. An intelligent terminal, characterized in that: It includes a memory and a processor, wherein the memory stores at least one instruction, at least one program, code set or instruction set, and the at least one instruction, at least one program, code set or instruction set is loaded and executed by the processor to implement a method for calibrating a metering flow channel in a NB remote ultrasonic gas meter as described in any one of claims 1 to 4.

6. A NB remote ultrasonic gas meter internal metering flow channel calibration system, characterized in that: include: A temperature sensor is used to measure the gas temperature in the flow channel to be measured; A pressure sensor is used to measure the gas pressure in the flow channel to be measured; The intelligent terminal according to claim 5 is communicatively connected to the flow sensor, the temperature sensor, and the pressure sensor, and is used to calibrate the ultrasonic gas meter according to the gas temperature, the gas pressure, the upstream flight time, and the downstream flight time to obtain a calibration result.

7. A computer-readable storage medium, characterized in that The readable storage medium stores at least one instruction, at least one program, code set or instruction set, and the at least one instruction, at least one program, code set or instruction set is loaded and executed by the processor to implement a method for calibrating the metering flow channel in a NB remote ultrasonic gas meter as described in any one of claims 1 to 4.

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