Gas flow detection method, controller and gas equipment

Abstract

The invention discloses a fuel gas flow detection method, a controller and fuel gas equipment, and relates to the technical field of fuel gas equipment.The fuel gas flow detection method is used for the fuel gas equipment, and the fuel gas equipment comprises a fuel gas pipe, a pressure sensor arranged on the fuel gas pipe and a control valve used for closing or opening the fuel gas pipe. The gas flow detection method comprises the steps that under the condition that a control valve is switched on, a first pressure value detected by a pressure sensor is obtained; under the condition that the control valve is cut off, a second pressure value detected by the pressure sensor is obtained; under the condition that the second pressure value is zero, the flow of gas flowing through the gas pipe is determined according to the obtained first pressure value; and under the condition that the second pressure value is not zero, the second pressure value is determined to be an error value, and the gas flow flowing through the gas pipe is determined according to the difference value between the obtained first pressure value and the error value. The gas flow detection method provided by the invention aims to improve the accuracy of gas flow detection in gas equipment by eliminating actual errors.

Description

Technical Field

[0001] The present invention relates to the technical field of gas equipment, and in particular to a gas flow detection method, a controller and a gas equipment. Background Art

[0002] Gas equipment is a device that uses fuels such as natural gas or liquefied petroleum gas for heating. Specifically, it generates heat by burning natural gas or liquefied petroleum gas, and transfers the heat to water or other heat media to achieve the functions of heating and hot water supply. It is mainly used for heating and domestic hot water supply in homes or commercial buildings.

[0003] At present, the gas consumption of gas equipment is large, and the gas flow of the gas equipment needs to be detected in order to take corresponding measures. The gas flow detection method in the relevant technology needs to use a gas flow meter. In actual applications, the gas flow measured by the gas flow meter will have deviations, and this deviation is difficult to eliminate directly, or complex technical adjustments and hardware replacements are required to eliminate the deviation. Therefore, the traditional gas flow detection method has the problem of low measurement accuracy. Summary of the invention

[0004] The main purpose of the present invention is to provide a gas flow detection method, a controller and a gas device, aiming to improve the accuracy of gas flow detection in the gas device.

[0005] To achieve the above object, the present invention proposes a gas flow detection method, which is used for a gas device, wherein the gas device includes a gas pipe, a pressure sensor provided on the gas pipe, and a control valve for cutting off or conducting the gas pipe. The gas flow detection method includes:

[0006] When the control valve is turned on, obtaining a first pressure value detected by the pressure sensor;

[0007] When the control valve is cut off, obtaining a second pressure value detected by the pressure sensor;

[0008] When the second pressure value is zero, determining the gas flow rate flowing through the gas pipe with the obtained first pressure value;

[0009] When the second pressure value is not zero, the second pressure value is determined as an error value, and the gas flow rate flowing through the gas pipe is determined by the difference between the obtained first pressure value and the error value.

[0010] In one embodiment, when the second pressure value is zero, determining the gas flow rate flowing through the gas pipe based on the acquired first pressure value includes:

[0011] When the second pressure value is zero, determining a first average velocity of the gas according to the acquired first pressure value and a preset gas density;

[0012] The product of the first average velocity and the pipe cross-sectional area of ​​the gas pipe is determined as the gas flow rate of the gas pipe.

[0013] In one embodiment, the first average velocity of the gas is determined according to the acquired first pressure value and the preset gas density as follows:

[0014] Dividing twice the first pressure value by a preset gas density to obtain a first calculated value;

[0015] A negative quadratic operation is performed on the first calculated value to obtain a second calculated value, and the second calculated value is determined as the first average speed of the fuel gas.

[0016] In one embodiment, when the second pressure value is not zero, determining the second pressure value as an error value, and determining the gas flow rate flowing through the gas pipe by the difference between the obtained first pressure value and the error value includes:

[0017] When the second pressure value is not zero, determining a second average velocity of the gas according to the difference between the first pressure value and the second pressure value and a preset gas density;

[0018] The gas flow rate of the gas pipe is determined according to the product of the second average velocity and the pipe cross-sectional area of ​​the gas pipe.

[0019] In one embodiment, when the second pressure value is not zero, the second average velocity of the gas is determined according to the difference between the first pressure value and the second pressure value and the preset gas density:

[0020] subtracting the second pressure value from the first pressure value to obtain a third calculated value;

[0021] Dividing twice the third calculated value by a preset gas density to obtain a fourth calculated value;

[0022] A negative quadratic operation is performed on the fourth calculated value to obtain a fifth calculated value, and the fifth calculated value is determined as the second average speed of the fuel gas.

[0023] In one embodiment, the gas flow detection method further includes:

[0024] When the second pressure value is not zero and the second pressure value is greater than the first preset pressure value, it is determined that there is a gas leakage in the gas pipe when the control valve is cut off, and the difference between the second pressure value and the first preset pressure value is determined as the error value, and the gas flow rate flowing through the gas pipe is determined by the difference between the obtained first pressure value and the error value.

[0025] In one embodiment, the gas flow detection method further includes:

[0026] When it is determined that there is a gas leak in the gas pipe when the control valve is cut off, an alarm signal indicating the gas leak is output.

[0027] In one embodiment, determining the difference between the second pressure value and the first preset pressure value as an error value, and determining the gas flow rate flowing through the gas pipe based on the difference between the obtained first pressure value and the error value includes:

[0028] When the second pressure value is not zero and the second pressure value is greater than the first preset pressure value, determining a third average speed of the gas according to the difference between the acquired second pressure value and the first preset pressure value and a preset gas density;

[0029] The gas flow rate of the gas pipe is determined according to the product of the third average speed and the gas pipe.

[0030] In one embodiment, when the second pressure value is not zero and the second pressure value is greater than the first preset pressure value, the third average speed of the gas is determined according to the difference between the obtained second pressure value and the first preset pressure value and the preset gas density:

[0031] subtracting the first preset pressure value from the second pressure value to obtain a sixth calculated value;

[0032] Dividing twice the sixth calculated value by a preset gas density to obtain a seventh calculated value;

[0033] A negative quadratic operation is performed on the seventh calculated value to obtain an eighth calculated value, and the fifth calculated value is determined as the third average speed of the fuel gas.

[0034] In one embodiment, the gas flow detection method further includes:

[0035] Obtain the first pressure value detected in the current cycle and the first pressure value detected in the previous cycle;

[0036] When the difference between the first pressure value detected in the current cycle and the first pressure value detected in the previous cycle is not greater than the second preset pressure value, it is determined that the gas pressure detection of the gas pipe is normal;

[0037] When the difference between the first pressure value detected in the current cycle and the first pressure value detected in the previous cycle is greater than the second preset pressure value, the detection value of the pressure sensor is error calibrated, and then the gas flow rate flowing through the gas pipe is calculated based on the detection value of the calibrated pressure sensor.

[0038] In one embodiment, when the control valve is turned on, obtaining the first pressure value detected by the pressure sensor includes: when the control valve is turned on and the turn-on time reaches a first preset time, obtaining the first pressure value detected by the pressure sensor;

[0039] Furthermore, when the control valve is cut off, acquiring the second pressure value detected by the pressure sensor includes: when the control valve is cut off and the cut-off time reaches a second preset time, acquiring the second pressure value detected by the pressure sensor.

[0040] The present invention also provides a controller, which is used to implement the gas flow detection method as described in any one of the above items.

[0041] The present invention also provides a gas device, the gas device comprising:

[0042] A gas main body having a gas pipe;

[0043] a pressure sensor, disposed in the gas pipe, for detecting the flow of gas in the gas pipe and generating a corresponding pressure signal according to the flow of gas in the gas pipe;

[0044] A controller, used to determine the gas flow in the gas pipe according to the pressure signal;

[0045] A control valve, provided on the gas pipe, the control valve is used to cut off or conduct the gas pipe;

[0046] As the controller described above, the controller is used to obtain a first pressure value detected by the pressure sensor when the control valve is turned on, and a second pressure value detected by the pressure sensor when the control valve is turned off; and is used to determine the gas flow through the gas pipe based on the obtained first pressure value when the second pressure value is zero; and to determine the second pressure value as an error value when the second pressure value is not zero, and to determine the gas flow through the gas pipe based on the difference between the obtained first pressure value and the error value.

[0047] In one embodiment, the gas equipment is one of a gas heating water heater, a gas water heater and a gas heating furnace.

[0048] The gas flow detection method provided by the present invention is intended to improve the accuracy of gas flow detection in gas equipment. Specifically, a pressure sensor and a control valve are installed in the gas pipe of the gas equipment; when the control valve cuts off the gas pipe, a first pressure value of the pressure sensor is obtained, and the pressure value is the initial pressure value of the pressure sensor, which is used to characterize the existing error value. Then the gas pipe is connected to obtain a second pressure value. That is, when the first pressure value is not zero, that is, when there is an error, the difference between the first pressure value and the second pressure value is combined to calculate the gas flow through the gas pipe. In this way, the error is eliminated and the detection accuracy of the pressure sensor is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0050] Figure 1 A schematic structural diagram of a first embodiment of a gas flow detection method provided by the present invention;

[0051] Figure 2 A schematic diagram of the structure of a second embodiment of the gas flow detection method provided by the present invention;

[0052] Figure 3 A schematic structural diagram of a third embodiment of a gas flow detection method provided by the present invention;

[0053] Figure 4 A schematic structural diagram of a fourth embodiment of a gas flow detection method provided by the present invention;

[0054] Figure 5 A schematic structural diagram of a fifth embodiment of a gas flow detection method provided by the present invention;

[0055] Figure 6 A schematic structural diagram of a sixth embodiment of a gas flow detection method provided by the present invention;

[0056] Figure 7 A structural schematic diagram of a seventh embodiment of a gas flow detection method provided by the present invention;

[0057] Figure 8 A schematic structural diagram of an eighth embodiment of a gas flow detection method provided by the present invention;

[0058] Fig. 9 This is a structural schematic diagram of a ninth embodiment of the gas flow detection method provided by the present invention.

[0059] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0060] 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.

[0061] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0062] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0063] Gas equipment is a device that uses fuels such as natural gas or liquefied petroleum gas for heating. Specifically, it generates heat by burning natural gas or liquefied petroleum gas, and transfers the heat to water or other heat media to achieve the functions of heating and hot water supply. It is mainly used for heating and domestic hot water supply in homes or commercial buildings.

[0064] At present, the gas consumption of gas equipment is large, and the gas flow of the gas equipment needs to be detected in order to take corresponding measures. The gas flow detection method in the relevant technology needs to use a gas flow meter. In actual applications, the gas flow measured by the gas flow meter will have deviations, and this deviation is difficult to eliminate directly, or complex technical adjustments and hardware replacements are required to eliminate the deviation. Therefore, the traditional gas flow detection method has the problem of low measurement accuracy.

[0065] In order to improve the detection accuracy of gas flow, the present invention proposes a gas flow detection method, which is used for gas equipment, and the gas equipment includes a gas pipe, a pressure sensor arranged in the gas pipe for detecting gas flow, and a control valve for cutting off or conducting the gas pipe. It can be understood that the gas equipment can be a gas water heater, a gas wall-mounted boiler, a gas cooker, a gas generator, a gas dryer, etc., and the specific equipment is not limited here. The gas equipment includes a gas pipe, which is a channel for gas flow and is responsible for transporting gas from the supply source to the use point (such as a burner or a water heater), and the gas flow detection method is used to detect the gas flow flowing through the gas pipe; the pressure sensor is installed on the gas pipe, which can sense and respond to the pressure changes generated when the gas flows in the gas pipe, and generate a pressure signal for subsequent processing or monitoring. The control valve is used to control the on and off of the gas pipe, that is, it can cut off or conduct the gas flow, and can adjust the gas flow or cut off the gas supply in an emergency as needed.

[0066] In one embodiment, if Figure 1 As shown, the gas flow detection method may include steps S100-S400.

[0067] In this embodiment, step S100: when the control valve is turned on, obtain the first pressure value detected by the pressure sensor. It can be understood that first, ensure that the control valve of the gas equipment is in the turned-on state, that is, the gas can flow freely through the gas pipe. Then, read the first pressure value detected by the pressure sensor installed on the gas pipe. The first pressure value reflects the pressure state in the gas pipe when the gas flows normally, and is one of the basic data for subsequent calculation of the gas flow.

[0068] In this embodiment, step S200: when the control valve is cut off, obtain the second pressure value detected by the pressure sensor. It is understandable that after the control valve is closed, the second pressure value detected by the pressure sensor is read again. Theoretically, if the gas pipe is completely sealed and there is no leakage, then after the control valve is closed, the pressure in the gas pipe should drop rapidly and eventually approach zero. But in fact, due to various factors such as system sealing, temperature changes, sensor accuracy, etc., the second pressure value may not be completely zero. In this step, the second pressure value reflects the static pressure of the gas pipe and its surrounding environment, and also reflects the initial error value of the pressure sensor. The obtained second pressure value is used as the reference value for subsequent calculations. In this way, the gas flow measurement process can be started in a stable and predictable state, providing a basis for improving detection accuracy in subsequent steps.

[0069] In this embodiment, step S300: when the second pressure value is zero, the gas flow rate flowing through the gas pipe is determined by using the obtained first pressure value. It can be understood that in this case, since the second pressure value is zero, it can be considered that the gas pipe and the pressure sensor are in an ideal working state. Therefore, the first pressure value (i.e., the pressure value when the gas flows) can be directly used to calculate the gas flow rate. Since there is a certain relationship between pressure and flow rate, in practice, the first average velocity of the gas in the gas pipe can be calculated based on the known gas density and the first pressure value through an appropriate conversion formula or model.

[0070] In this embodiment, step S400: when the second pressure value is not zero, the second pressure value is determined to be an error value, and the gas flow rate flowing through the gas pipe is determined by the difference between the first pressure value and the error value. It can be understood that when the second pressure value is not equal to zero, it means that there is a certain static pressure in the gas pipe before measurement, which may be caused by leakage of the gas pipe, incomplete exhaustion of the system, initial value of the pressure sensor or other reasons. At this time, the non-zero second pressure value is regarded as an error value, which represents the measurement error introduced due to non-ideal conditions (such as leakage, sensor deviation, etc.). In order to correct this error, it is necessary to subtract the error value from the first pressure value obtained in step S100 to obtain a corrected pressure value, and then use this corrected pressure value to calculate the gas flow rate. This can improve the accuracy of gas flow detection to a certain extent.

[0071] Steps S100 to S400 are applied to a gas wall-mounted boiler. First, before the gas wall-mounted boiler is ready to detect the gas flow, the control valve in the gas wall-mounted boiler is closed to ensure that there is no gas flowing in the gas pipe. At this time, the pressure value measured by the pressure sensor is the static pressure of the gas pipe and its surrounding environment, or the initial pressure value of the pressure sensor, that is, the second pressure value mentioned above. Comparing the second pressure value with 0 can intuitively reflect whether the initial pressure value of the pressure sensor deviates from the expected value, thereby characterizing the initial error of the pressure sensor. Then, open the control valve in the gas wall-mounted boiler, the pressure sensor will respond to the dynamic pressure change, and output the corresponding pressure value, that is, the first pressure value, to reflect the actual pressure during the gas flow process. Finally, start calculating the gas flow. When the second pressure value is not 0, the difference between the first pressure value and the second pressure value is used to determine the part of the first pressure value that characterizes the actual gas flow, and the corresponding gas flow can be determined by the first pressure value.

[0072] It is understandable that, because the preset program used in the above judgment method is a default value of 0 as a no-error situation; therefore, when the second pressure value is not compared with 0, the preset program needs to be processed. In addition, the above is only an application scenario of an embodiment, which is used to understand the solution and does not represent an actual limitation.

[0073] It is understandable that the specific logic implementation order of step S100 and step S200 can be swapped; similarly, the specific logic implementation order of step S300 and step S400 can be swapped.

[0074] In summary, the gas flow detection method provided by the present invention is intended to improve the accuracy of gas flow detection in gas equipment. Specifically, a pressure sensor and a control valve are installed in the gas pipe of the gas equipment; when the control valve cuts off the gas pipe, a second pressure value of the pressure sensor is obtained, and this pressure value is the initial pressure value of the pressure sensor, which is used to characterize the existing error value. Then the gas pipe is turned on to obtain the first pressure value. That is, when the second pressure value is not zero, that is, when there is an error, the difference between the second pressure value and the first pressure value is combined to calculate the gas flow through the gas pipe. In this way, the error is eliminated and the detection accuracy of the pressure sensor is improved.

[0075] In one embodiment, if Figure 2 As shown, step S300 may include steps S310 to S320.

[0076] In this embodiment, step S310: when the second pressure value is zero, determining the first average velocity of the gas according to the acquired first pressure value and the preset gas density.

[0077] In this embodiment, step S320: determining the product of the first average velocity and the pipe cross-sectional area of ​​the gas pipe as the gas flow rate of the gas pipe.

[0078] It is understandable that the average velocity of the gas in the gas pipe is estimated by using the basic principles of fluid mechanics, especially the Bernoulli equation or its simplified form, and the physical properties of the gas in combination with the first pressure value.

[0079] Furthermore, if Figure 3 As shown, step S310 includes steps S311 and S312.

[0080] In this embodiment, step S311: dividing twice the first pressure value by a preset gas density to obtain a first calculated value.

[0081] In this embodiment, step S312: performing a negative quadratic operation on the first calculated value to obtain a second calculated value, and determining the second calculated value as the first average speed of the gas.

[0082] It can be understood that in step S311 to step S312, specifically, to calculate the first average velocity v, the relationship between pressure and density can be used: Among them, P 1 is the first pressure value, and ρ is the density of the gas. After obtaining the first average velocity of the gas in the gas pipe, the continuity equation of the fluid, that is, the principle that flow equals velocity multiplied by area, can be used to calculate the gas flow. Here, area refers to the cross-sectional area of ​​the gas pipe, which is a known or measurable parameter. By multiplying the first average velocity by the cross-sectional area of ​​the gas pipe, the flow of the gas in a given time can be obtained. Specifically, to calculate the gas flow, the formula Q=Av can be used; wherein Q is the gas flow, A is the cross-sectional area of ​​the gas pipe, and v is the first average velocity of the gas. In this way, the specific gas flow can be calculated.

[0083] Furthermore, if Figure 4 As shown, step S400 may include steps S410 to S420.

[0084] In this embodiment, step S410: when the second pressure value is not zero, determine the second average speed of the gas according to the difference between the first pressure value and the second pressure value and the preset gas density. It can be understood that, similar to step S310, here we use the pressure difference (i.e., the difference between the second pressure value and the first pressure value) instead of the first pressure value alone to calculate the second average speed of the gas.

[0085] In this embodiment, step S420: determining the gas flow rate of the gas pipe according to the product of the second average velocity and the pipe cross-sectional area of ​​the gas pipe.

[0086] In this embodiment, if Figure 5 As shown, step S410 includes steps S411 to S413.

[0087] Step S411: subtract the second pressure value from the first pressure value to obtain a third calculated value.

[0088] Step S412: Divide twice the third calculated value by a preset gas density to obtain a fourth calculated value.

[0089] Step S413: performing a negative quadratic operation on the fourth calculated value to obtain a fifth calculated value, and determining the fifth calculated value as the second average speed of the fuel gas.

[0090] Specifically, the second average speed v 1 You can use the formula Calculate, where P 1 is the first pressure value, P 2is the second pressure value, ρ is the density of the gas. Similarly, through Q = Av 1 , the corresponding gas flow can be calculated.

[0091] It can be understood that the difference between step S411-step S413 and step S311-step S312 is that the former uses the difference between the first pressure value and the second pressure value (i.e., the pressure difference) to calculate the second average speed of the gas, while the latter directly uses the first pressure value to calculate the first average speed of the gas. Through this calculation, the corresponding error can be directly eliminated to calculate the actual gas flow rate.

[0092] In one embodiment, if Figure 6 As shown, the gas flow detection method may also include step S500: when the second pressure value is not zero and the second pressure value is greater than the first preset pressure value, determining that there is a gas leakage in the gas pipe when the control valve is cut off, and determining the difference between the second pressure value and the first preset pressure value as the error value, and determining the gas flow flowing through the gas pipe based on the difference between the obtained first pressure value and the error value.

[0093] It is understandable that, ideally, after the control valve is shut off, the pressure in the gas pipe should drop rapidly to near zero. If the second pressure value is still high and exceeds the preset threshold, it means that there may be a leak in the system, resulting in the pressure in the gas pipe not being able to drop completely to zero. In addition, the first preset pressure value is a threshold value used to distinguish between static pressure under normal conditions and abnormal pressure under leakage conditions. This threshold value can be set according to the characteristics of the specific gas equipment and the use environment to ensure that there will be no false alarms under normal conditions, and that leaks can be detected in time when they occur.

[0094] In this embodiment, when it is determined that there is a gas leak in the gas pipe when the control valve is cut off, an alarm signal indicating the presence of a gas leak is output.

[0095] It is understood that when the system detects that the second pressure value exceeds the first preset pressure value, the alarm mechanism will be triggered immediately to notify the user or maintenance personnel through sound and light alarms or other means so that timely measures can be taken to repair the leak and ensure the safe operation of the gas equipment. In addition, the system can also record the time and duration of the leak for subsequent analysis and maintenance.

[0096] In this embodiment, if Figure 7 As shown, step S500 may include steps S510 to S520.

[0097] Step S510: when the second pressure value is not zero and the second pressure value is greater than the first preset pressure value, determine a third average speed of the gas according to the difference between the acquired second pressure value and the first preset pressure value and a preset gas density.

[0098] Step S520: determining the gas flow rate of the gas pipe according to the product of the third average speed and the gas pipe.

[0099] In this embodiment, if Figure 8 As shown, step S510 may include steps S511 to S513.

[0100] Step S511: subtracting the first preset pressure value from the second pressure value to obtain a sixth calculated value;

[0101] Step S512: dividing twice the sixth calculated value by a preset gas density to obtain a seventh calculated value;

[0102] Step S513: performing a negative quadratic operation on the seventh calculated value to obtain an eighth calculated value, and determining the fifth calculated value as the third average speed of the gas.

[0103] Specifically, the leaked gas flow rate can also be detected by the second pressure value detected by the pressure sensor. Similarly, using the formula And the formula Q = Av 2 ; Where Q is the gas leakage flow, A is the cross-sectional area of ​​the gas pipe, v 2 is the third average velocity of the gas. In this way, the specific gas flow rate corresponding to the second pressure value can be determined, and the physical meaning in this embodiment is the specific leakage amount of the gas.

[0104] In one embodiment, if Fig. 9 As shown, the gas flow detection method may further include steps S610 to S630.

[0105] Step S610: Obtain the first pressure value detected in the current cycle and the first pressure value detected in the previous cycle. In this step, the system needs to obtain the first pressure detection value detected in the current cycle and the first pressure value detected in the previous cycle. Specifically, the first pressure detection value detected in the current cycle refers to the pressure value detected by the pressure sensor when the control valve is turned on in the current detection cycle. The first pressure value detected in the previous cycle refers to the pressure value detected by the pressure sensor in the previous detection cycle, also when the control valve is turned on. The acquisition of these two values ​​is for subsequent comparison and judgment to ensure the stability and accuracy of pressure detection.

[0106] Step S620: When the difference between the first pressure value detected in the current cycle and the first pressure value detected in the previous cycle is not greater than the second preset pressure value, it is determined that the gas pressure detection of the gas pipe is normal. In this step, the system calculates the difference between the first pressure detection value detected in the current cycle and the first pressure value detected in the previous cycle. Then, this difference is compared with the second preset pressure value. The second preset pressure value is a preset threshold value used to determine whether the change in the pressure detection value is within a normal range. If the calculated difference is not greater than the second preset pressure value, it means that the change in the detection value of the pressure sensor is within a reasonable range and the gas pressure detection is normal. This means that the system can continue to use the current pressure detection value for subsequent flow calculations without the need for additional calibration or adjustment.

[0107] Step S630: When the difference between the first pressure value detected in the current cycle and the first pressure value detected in the previous cycle is greater than the second preset pressure value, the detection value of the pressure sensor is calibrated for error, and then the gas flow through the gas pipe is calculated based on the detection value of the calibrated pressure sensor. In this step, if the difference between the first pressure detection value detected in the current cycle and the first pressure value detected in the previous cycle is greater than the second preset pressure value, it means that the detection value of the pressure sensor changes abnormally and there may be an error. In this case, the system will perform error calibration on the detection value of the pressure sensor. The specific operation includes determining a reasonable error correction value, which can be determined by historical data, calibration values ​​or other methods. Then, the first pressure detection value detected in the current cycle is subtracted from the error correction value to obtain the calibrated pressure detection value.

[0108] It is understandable that, under normal circumstances, the deviation of the first pressure value obtained in the same detection cycle will not be too large. For example, if the detection cycle is one year, the first pressure value will not change much within one year. If the difference between the first pressure value detected in the next detection cycle and the pressure value detected in the previous detection cycle exceeds the second preset pressure value, this may indicate that the pressure sensor has failed or the external conditions have changed significantly. At this time, the system needs to perform error calibration on the detection value of the pressure sensor to ensure that the subsequent gas flow calculation is accurate. In this way, potential problems can be discovered and corrected in a timely manner to ensure the normal operation and safe use of gas equipment.

[0109] It is understandable that the preset period can be determined according to actual application conditions.

[0110] In one embodiment, step S100 further includes obtaining a first pressure value detected by the pressure sensor when the control valve is turned on and the turn-on time reaches a second preset time. And step S200 includes obtaining a second pressure value detected by the pressure sensor when the control valve is turned off and the turn-off time reaches the first preset time.

[0111] It is understandable that step S100 includes obtaining a first pressure value detected by the pressure sensor when the control valve is turned on and the on time reaches a second preset time. This is done to ensure that the gas fully flows in the gas pipe and reaches a stable state, so that the first pressure value can accurately reflect the pressure when the gas flows. Step S200 includes obtaining a second pressure value detected by the pressure sensor when the control valve is turned off and the cut-off time reaches a first preset time. This is to ensure that the pressure in the gas pipe can be completely stabilized and reach a static state, so that the second pressure value can accurately reflect the static pressure and the initial error value of the sensor. By waiting for the preset time when the control valve is turned on and off, the accuracy of pressure detection can be improved, providing a reliable data basis for subsequent gas flow calculations.

[0112] The present invention also proposes a controller, which adopts the gas flow detection method in the above embodiment to solve the technical problem of gas flow detection. Compared with the prior art, the beneficial effects of the controller provided by the present application are the same as the beneficial effects of the gas flow detection method provided by the above embodiment, and other technical features in the controller are the same as the features disclosed in the above embodiment method, which will not be repeated here.

[0113] It is understandable that the controller can be applied to different devices, including gas equipment. After the controller is applied to the gas equipment, it can be used to detect the gas flow of the gas pipe in the gas equipment and can eliminate certain detection errors to improve the detection accuracy of the gas flow.

[0114] The present invention also provides a gas device, including a gas main body, a pressure sensor, a control valve and a controller, wherein the gas main body has a gas pipe; the pressure sensor is arranged on the gas pipe, and the pressure sensor is used to detect the flow of gas in the gas pipe, and generate a corresponding pressure signal according to the flow of gas in the gas pipe; the control valve is arranged on the gas pipe, and the control valve is used to cut off or conduct the gas pipe. The controller is used to obtain a first pressure value detected by the pressure sensor when the control valve is conducted, and a second pressure value detected by the pressure sensor when the control valve is cut off; and is used to determine the gas flow rate flowing through the gas pipe with the first pressure value obtained when the second pressure value is zero; and to determine the second pressure value as an error value when the second pressure value is not zero, and to determine the gas flow rate flowing through the gas pipe with the difference between the first pressure value obtained and the error value.

[0115] It should be noted that the specific functions of the controller included in the gas equipment refer to the above embodiments. Since this controller adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.

[0116] In one embodiment, the gas device is one of a gas heating water heater, a gas water heater and a gas heating furnace. The gas flow detection method or controller provided by the present invention is applied to the above-mentioned gas device to detect the gas flow in the gas pipe of the gas device, and to a certain extent improve the detection accuracy by eliminating the deviation.

[0117] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A gas flow detection method, characterized in that: For a gas device, the gas device includes a gas pipe, a pressure sensor provided on the gas pipe, and a control valve for cutting off or conducting the gas pipe, and the gas flow detection method includes: When the control valve is turned on, obtaining a first pressure value detected by the pressure sensor; When the control valve is cut off, obtaining a second pressure value detected by the pressure sensor; When the second pressure value is zero, determining the gas flow rate flowing through the gas pipe with the obtained first pressure value; When the second pressure value is not zero, the second pressure value is determined as an error value, and the gas flow rate flowing through the gas pipe is determined by the difference between the obtained first pressure value and the error value.

2. The gas flow detection method according to claim 1, characterized in that: When the second pressure value is zero, determining the gas flow rate flowing through the gas pipe by using the acquired first pressure value includes: When the second pressure value is zero, determining a first average velocity of the gas according to the acquired first pressure value and a preset gas density; The product of the first average velocity and the pipe cross-sectional area of ​​the gas pipe is determined as the gas flow rate of the gas pipe.

3. The gas flow detection method according to claim 2, characterized in that: The method of determining the first average velocity of the gas according to the acquired first pressure value and the preset gas density is specifically: Dividing twice the first pressure value by a preset gas density to obtain a first calculated value; A negative quadratic operation is performed on the first calculated value to obtain a second calculated value, and the second calculated value is determined as the first average speed of the fuel gas.

4. The gas flow detection method according to claim 1, characterized in that: When the second pressure value is not zero, determining the second pressure value as an error value, and determining the gas flow rate flowing through the gas pipe by the difference between the obtained first pressure value and the error value comprises: When the second pressure value is not zero, determining a second average velocity of the gas according to the difference between the first pressure value and the second pressure value and a preset gas density; The gas flow rate of the gas pipe is determined according to the product of the second average velocity and the pipe cross-sectional area of ​​the gas pipe.

5. The gas flow detection method according to claim 4, characterized in that: When the second pressure value is not zero, the second average velocity of the gas is determined according to the difference between the first pressure value and the second pressure value and the preset gas density: subtracting the second pressure value from the first pressure value to obtain a third calculated value; Dividing twice the third calculated value by a preset gas density to obtain a fourth calculated value; A negative quadratic operation is performed on the fourth calculated value to obtain a fifth calculated value, and the fifth calculated value is determined as the second average speed of the fuel gas.

6. The gas flow detection method according to claim 1, characterized in that: The gas flow detection method further comprises: When the second pressure value is not zero and the second pressure value is greater than the first preset pressure value, it is determined that there is a gas leakage in the gas pipe when the control valve is cut off, and the difference between the second pressure value and the first preset pressure value is determined as the error value, and the gas flow rate flowing through the gas pipe is determined by the difference between the obtained first pressure value and the error value.

7. The gas flow detection method according to claim 6, characterized in that: The gas flow detection method further comprises: When it is determined that there is a gas leak in the gas pipe when the control valve is cut off, an alarm signal indicating the gas leak is output.

8. The gas flow detection method according to claim 6, characterized in that: The step of determining the difference between the second pressure value and the first preset pressure value as an error value, and determining the gas flow rate flowing through the gas pipe based on the difference between the first pressure value and the error value comprises: When the second pressure value is not zero and the second pressure value is greater than the first preset pressure value, determining a third average speed of the gas according to the difference between the acquired second pressure value and the first preset pressure value and a preset gas density; The gas flow rate of the gas pipe is determined according to the product of the third average speed and the gas pipe.

9. The gas flow detection method according to claim 8, characterized in that: When the second pressure value is not zero and the second pressure value is greater than the first preset pressure value, the third average speed of the gas is determined according to the difference between the obtained second pressure value and the first preset pressure value and the preset gas density: subtracting the first preset pressure value from the second pressure value to obtain a sixth calculated value; Dividing twice the sixth calculated value by a preset gas density to obtain a seventh calculated value; A negative quadratic operation is performed on the seventh calculated value to obtain an eighth calculated value, and the fifth calculated value is determined as the third average speed of the fuel gas.

10. The gas flow detection method according to any one of claims 1 to 9, characterized in that: The gas flow detection method further comprises: Obtain the first pressure value detected in the current cycle and the first pressure value detected in the previous cycle; When the difference between the first pressure value detected in the current cycle and the first pressure value detected in the previous cycle is not greater than the second preset pressure value, it is determined that the gas pressure detection of the gas pipe is normal; When the difference between the first pressure value detected in the current cycle and the first pressure value detected in the previous cycle is greater than the second preset pressure value, the detection value of the pressure sensor is error calibrated, and then the gas flow rate flowing through the gas pipe is calculated based on the detection value of the calibrated pressure sensor.

11. The gas flow detection method according to any one of claims 1 to 9, characterized in that: The obtaining of the first pressure value detected by the pressure sensor when the control valve is turned on comprises: obtaining the first pressure value detected by the pressure sensor when the control valve is turned on and the turn-on time reaches a first preset time; Furthermore, when the control valve is cut off, acquiring the second pressure value detected by the pressure sensor includes: when the control valve is cut off and the cut-off time reaches a second preset time, acquiring the second pressure value detected by the pressure sensor.

12. A controller, characterized in that: The controller is used to implement the gas flow detection method according to any one of claims 1 to 11.

13. A gas equipment, characterized in that: The gas equipment comprises: A gas main body having a gas pipe; a pressure sensor, disposed in the gas pipe, for detecting the flow of gas in the gas pipe and generating a corresponding pressure signal according to the flow of gas in the gas pipe; A control valve, provided on the gas pipe, the control valve is used to cut off or conduct the gas pipe; The controller as claimed in claim 12, wherein the controller is used to obtain a first pressure value detected by the pressure sensor when the control valve is turned on, and a second pressure value detected by the pressure sensor when the control valve is turned off; and is used to determine the gas flow through the gas pipe based on the first pressure value obtained when the second pressure value is zero; and to determine the second pressure value as an error value when the second pressure value is not zero, and to determine the gas flow through the gas pipe based on the difference between the first pressure value obtained and the error value.

14. The gas device according to claim 13, characterized in that: The gas equipment is one of a gas heating water heater, a gas water heater and a gas heating furnace.

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