Flow compensation method and device of differential pressure flow sensor and breathing machine

Abstract

The invention provides a flow compensation method and device of a differential pressure flow sensor and a breathing machine, and relates to the technical field of breathing machines. The method comprises the following steps: acquiring a first target flow velocity value and a first target pressure difference value at different target gas temperatures; acquiring a second target flow velocity value and a second target pressure difference value at each target rotating speed point; fitting the first target flow velocity value and the first target pressure difference value to obtain a target gas temperature compensation coefficient; determining a target flow velocity compensation difference value according to the target gas temperature compensation coefficient, the second target pressure difference value and the second target flow velocity value; fitting the target flow velocity compensation difference value and the second target pressure difference value to obtain a target flow velocity compensation coefficient; and the current gas temperature and the current pressure difference value are obtained, and the target compensation flow is determined according to the current gas temperature, the current pressure difference value, the target flow velocity compensation coefficient and the target gas temperature compensation coefficient. The problem of inaccurate flow measurement of the differential pressure flow sensor under different gas temperatures can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of ventilators, and in particular to a flow compensation method and device for a differential pressure flow sensor and a ventilator. Background Art

[0002] During the use of the ventilator's differential pressure flow sensor, the fitting calculation of the flow rate is easily affected by the gas temperature, resulting in deviations in the dynamic performance of the ventilator, thereby affecting the ventilator's ventilation performance and the user's actual experience.

[0003] In the related technology 1, a flow sensor with temperature compensation function is directly used. The sensor manufacturer integrates temperature compensation function before leaving the factory, and the user does not need to compensate, and the output of this type of sensor is the compensated flow rate value. Its shortcomings are obvious, that is, this type of sensor is only compensated before leaving the factory, and the repeatability of use is poor. After the sensor has been used for a period of time, due to the influence of environmental conditions such as water vapor and pressure, the measurement data may be biased, resulting in relatively inaccurate measurement results. In addition, this type of integrated digital sensor is expensive. The cost advantage is not obvious enough.

[0004] In the related technology 2, the fitting relationship between the pressure value of the differential pressure sensor and the actual flow rate value is obtained through calibration fitting. When used, it is not used with temperature compensation, and the actual flow rate is directly fitted and calculated. Because it does not have temperature compensation, the pressure measured by the differential pressure sensor will have deviations due to the different molecular densities of the gas at the same flow rate and different temperatures, so the calculated flow rate value will have errors, and the actual tidal volume of the gas will eventually have deviations, thus affecting the control and ventilator performance. Therefore, the accuracy of the flow measured by this method needs to be improved. Summary of the invention

[0005] The purpose of the present invention is to provide a method and a device to address the deficiencies in the above-mentioned prior art.

[0006] To achieve the above purpose, the technical solution adopted in the embodiment of the present application is as follows:

[0007] In a first aspect, an embodiment of the present application provides a flow compensation method for a differential pressure flow sensor, characterized in that it includes: for a target ventilator, obtaining a first target flow rate value and a first target pressure differential value at different target gas temperatures; obtaining a second target flow rate value and a second target pressure differential value at each target speed point output by the target ventilator; fitting the first target flow rate value and the first target pressure differential value at different target gas temperatures to obtain a target gas temperature compensation coefficient; determining a target flow rate compensation difference according to the target gas temperature compensation coefficient, the second target pressure differential value, and the second target flow rate value; fitting the target flow rate compensation difference and the second target pressure differential value to obtain a target flow rate compensation coefficient; during the ventilation process of the target ventilator, obtaining a current gas temperature and a current pressure differential value, and determining the target compensated flow according to the current gas temperature, the current pressure differential value, the target flow rate compensation coefficient, and the target gas temperature compensation coefficient.

[0008] In one embodiment, obtaining the first target flow rate value and the first target pressure difference value at different target gas temperatures includes: determining a target data point set based on a target flow range of the target ventilator; and for each target data point in the target data point set, obtaining the first target flow rate value and the first target pressure difference value at different target gas temperatures.

[0009] In one embodiment, determining the target data point set based on the target flow range of the target ventilator includes: dividing the target flow range of the target ventilator into a plurality of target data points, and determining the target data point set based on the plurality of target data points.

[0010] In one embodiment, obtaining the first target flow rate value and the first target pressure difference value at different target gas temperatures includes: obtaining the first target flow rate value and the first target pressure difference value at different target gas temperatures through a gas metering and calibration device.

[0011] In one embodiment, obtaining the second target flow rate value and the second target pressure difference value at each target speed point output by the target ventilator includes: during the power-on self-test process of the target ventilator, obtaining the second target flow rate value and the second target pressure difference value at each target speed point output by the target ventilator.

[0012] In one embodiment, the fitting of the first target flow rate values ​​and the first target pressure difference values ​​at different target gas temperatures to obtain a target gas temperature compensation coefficient includes: establishing a target mathematical model for the first target flow rate values ​​and the first target pressure difference values ​​at different target gas temperatures, and fitting the first target flow rate values ​​and the first target pressure difference values ​​at different target gas temperatures according to the target mathematical model to obtain the target gas temperature compensation coefficient; the target mathematical model is shown in the following formula:

[0013] f(x,y)=a*x+b*y+c

[0014] Wherein, a, b, and c represent the target gas temperature compensation coefficients; x and y represent the first target flow rate value and the first target pressure difference value at different target gas temperatures; and f(x, y) represents the fitting result.

[0015] In one embodiment, determining the target flow rate compensation difference based on the target gas temperature compensation coefficient, the second target pressure difference value, and the second target flow rate value includes: determining a third target flow rate value corresponding to the second target pressure difference value based on the target gas temperature compensation coefficient; and determining the target flow rate compensation difference based on the third target flow rate value and the second target flow rate value.

[0016] In one embodiment, the target compensated flow rate is determined based on the current gas temperature, the current pressure difference value, the target flow rate compensation coefficient, and the target gas temperature compensation coefficient, including: determining the target temperature compensated flow rate based on the current gas temperature, the current pressure difference value, and the target gas temperature compensation coefficient; determining the target flow rate compensated flow rate based on the current gas temperature, the current pressure difference value, and the target flow rate compensation coefficient; determining the target compensated flow rate based on the target temperature compensated flow rate and the target flow rate compensation flow rate.

[0017] In the second aspect, an embodiment of the present application also provides a flow compensation device for a differential pressure flow sensor, comprising: an acquisition module, configured to acquire a first target flow rate value and a first target pressure difference value at different target gas temperatures for a target ventilator; to acquire a second target flow rate value and a second target pressure difference value at each target speed point output by the target ventilator; a first fitting module, configured to fit the first target flow rate value and the first target pressure difference value at different target gas temperatures to obtain a target gas temperature compensation coefficient; a first determination module, configured to determine a target flow rate compensation difference according to the target gas temperature compensation coefficient, the second target pressure difference value, and the second target flow rate value; a second fitting module, configured to fit the target flow rate compensation difference and the second target pressure difference value to obtain a target flow rate compensation coefficient; a second determination module, configured to acquire a current gas temperature and a current pressure difference value during ventilation of the target ventilator, and determine the target compensated flow according to the current gas temperature, the current pressure difference value, the target flow rate compensation coefficient, and the target gas temperature compensation coefficient.

[0018] In one embodiment, the acquisition module is configured to: determine a target data point set based on a target flow range of the target ventilator; and for each target data point in the target data point set, obtain the first target flow rate value and the first target pressure difference value at different target gas temperatures.

[0019] In one embodiment, the acquisition module is configured to: divide the target flow range of the target ventilator into a plurality of target data points, and determine the target data point set according to the plurality of target data points.

[0020] In one embodiment, the acquisition module is configured to: acquire the first target flow rate value and the first target pressure difference value at different target gas temperatures through a gas metering and calibration device.

[0021] In one embodiment, the acquisition module is configured to: during the power-on self-test process of the target ventilator, acquire the second target flow rate value and the second target pressure difference value at each target speed point output by the target ventilator.

[0022] In one embodiment, the first fitting module is configured to: establish a target mathematical model for the first target flow rate values ​​and the first target pressure difference values ​​at different target gas temperatures, and fit the first target flow rate values ​​and the first target pressure difference values ​​at different target gas temperatures according to the target mathematical model to obtain the target gas temperature compensation coefficient; the target mathematical model is shown in the following formula:

[0023] f(x,y)=a*x+b*y+c

[0024] Wherein, a, b, and c represent the target gas temperature compensation coefficients; x and y represent the first target flow rate value and the first target pressure difference value at different target gas temperatures; and f(x, y) represents the fitting result.

[0025] In one embodiment, the first determination module is configured to: determine a third target flow rate value corresponding to the second target pressure difference value according to the target gas temperature compensation coefficient; and determine the target flow rate compensation difference value according to the third target flow rate value and the second target flow rate value.

[0026] In one embodiment, the second determination module is configured to: determine the target temperature compensated flow rate based on the current gas temperature, the current pressure difference value, and the target gas temperature compensation coefficient; determine the target flow rate compensated flow rate based on the current gas temperature, the current pressure difference value, and the target flow rate compensation coefficient; determine the target compensated flow rate based on the target temperature compensated flow rate and the target flow rate compensated flow rate.

[0027] In the third aspect, an embodiment of the present application also provides a ventilator, comprising: a flow device; the air outlet of the flow device is connected to a breathing circuit and a main control chip; the main control chip is connected to a first pressure sensor, a second pressure sensor and a flow sensor; the flow sensor is arranged at the front end of the air outlet; the first pressure sensor is arranged on the side of the breathing circuit close to the flow device; the second pressure sensor is arranged on the side of the breathing circuit 630 away from the flow device through a pressure collection tube; the side of the breathing circuit away from the flow device is connected to a breathing interface.

[0028] In a fourth aspect, an embodiment of the present application provides a computer device, comprising: a processor, a storage medium and a bus, wherein the storage medium stores program instructions executable by the processor, and when the computer device is running, the processor communicates with the storage medium through the bus, and the processor executes the program instructions to perform the steps of any one of the above methods.

[0029] In a fifth aspect, an embodiment of the present application provides a non-volatile computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of any one of the above methods are performed.

[0030] The beneficial effects of the present application are as follows: by obtaining data tables of pressure difference values ​​and true flow rate values ​​at multiple different temperatures, performing three-dimensional data fitting on the data tables, and obtaining a fitting surface of the true flow rate, temperature, and pressure difference value of the pressure difference flow sensor, the gas flow rate at the current ambient temperature can be accurately calculated; in addition, the ventilator can self-correct the flow rate measurement error each time it is powered on for self-test, and can accurately measure the flow through the pressure difference sensor; through the dual flow compensation mechanism, the problem of inaccurate flow measurement of the pressure difference flow sensor at different gas temperatures can be solved, without the need for additional devices or sensors, the sensor has a simple structure and is reusable, and can repeatedly compensate and correct when a flow rate deviation occurs in the sensor; compared with other highly integrated flow sensors, the present application is lower in cost than other sensors, and has obvious cost advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0032] Figure 1 A schematic flow chart of a flow compensation method for a differential pressure flow sensor provided in an embodiment of the present application;

[0033] Figure 2 A schematic flow chart of a flow compensation method for a differential pressure flow sensor provided in an embodiment of the present application;

[0034] Figure 3 A schematic diagram of the corresponding relationship between a first target pressure difference value and a first target flow rate value in a flow compensation method of a pressure difference flow sensor provided in an embodiment of the present application;

[0035] Figure 4 A schematic flow chart of a flow compensation method for a differential pressure flow sensor provided in an embodiment of the present application;

[0036] Figure 5 A schematic flow chart of a flow compensation method for a differential pressure flow sensor provided in an embodiment of the present application;

[0037] Figure 6 A schematic diagram of the structure of a ventilator provided in an embodiment of the present application;

[0038] Figure 7 A schematic structural diagram of a flow compensation device of a differential pressure flow sensor provided in an embodiment of the present application;

[0039] Figure 8A schematic diagram of the structure of a computer device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0041] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0042] In the description of the present application, it should be noted that if the terms "upper", "lower", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, or is the orientation or position relationship in which the product of the application is usually placed when used. It is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0043] In addition, the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0044] It should be noted that, in the absence of conflict, the features in the embodiments of the present application may be combined with each other.

[0045] Figure 1 A flow chart of a flow compensation method for a differential pressure flow sensor provided in an embodiment of the present application; Figure 1 As shown, the method includes:

[0046] Step 110: for a target ventilator, obtain a first target flow rate value and a first target pressure difference value at different target gas temperatures; obtain a second target flow rate value and a second target pressure difference value at each target speed point output by the target ventilator.

[0047] Among them, the target gas temperature refers to the different gas temperatures of the target ventilator.

[0048] The first target flow rate value is the flow rate value of the target ventilator at different target gas temperatures.

[0049] The first target pressure difference value is the pressure difference value of the target ventilator at different target gas temperatures.

[0050] The first target flow rate value can be obtained through gas metering and calibration equipment, and the first target pressure differential value can be obtained by recording the pressure differential value of the pressure differential flow sensor at this time. In actual operation, the first target flow rate value and the first target pressure differential value at different target gas temperatures of several target data points are obtained. These several target data points are determined according to the flow rate range of the target ventilator, specifically, Figure 2 As shown, the above step 110 may include the following steps 210 and 220:

[0051] Step 210: Determine a target data point set according to a target flow range of a target ventilator.

[0052] The flow rate, also called flow velocity, is expressed in L / min.

[0053] The target flow range is the flow range of the target ventilator.

[0054] The target data point is a data point determined according to the target flow range of the target ventilator.

[0055] The target data point set is composed of a plurality of target data points; the target data points can be obtained by evenly dividing the target flow range of the target ventilator. Specifically, the above step 210 may include the following steps:

[0056] The target flow rate range of the target ventilator is evenly divided into a plurality of target data points, and a target data point set is determined according to the plurality of target data points.

[0057] Exemplarily, the target flow rate range of the target ventilator is 0-200 L / min, which is evenly divided into n target data points. Then, the target data point set consists of these n target data points.

[0058] Step 220: For each target data point in the target data point set, obtain a first target flow rate value and a first target pressure difference value at different target gas temperatures.

[0059] For example, the first target flow rate value FLOW1 of each target data point in the target data point set can be obtained as follows: n} and the first target pressure difference value AD1 = {ad1, ad2, ad3, ... ad n}, through the correspondence between the n first target flow rate values ​​and the first target pressure difference values, a single pressure difference value-flow rate value data table can be obtained to record the target gas temperature T1 at this time; further, the target gas temperature is changed, and the above steps are repeated to obtain different target gas temperatures T={T1,T2,T3,......T m} (for example: 0℃~60℃) m sheets of pressure difference value-flow rate value data table, such as Figure 3 shown.

[0060] In actual operation, the first target flow rate value and the first target pressure difference value may be obtained through gas metering and calibration equipment; specifically, the above step 110 (220) may include the following steps:

[0061] The first target flow rate value and the first target pressure difference value at different target gas temperatures are obtained through gas metering and calibration equipment.

[0062] Among them, the gas metering and calibration equipment can be PF300; PF-300 is a gas flow analyzer, which is mainly used for comprehensive quality inspection of various medical equipment such as ventilators, anesthesia ventilators, etc. It has the ability to measure bidirectional flow, pressure, temperature, humidity and oxygen concentration, and is suitable for the measurement of adults, children and high-frequency ventilation modes.

[0063] The main functions and application areas of PF-300 are as follows;

[0064] (1) Bidirectional flow measurement: It can measure the gas flow of a ventilator or anesthesia machine during inhalation and exhalation.

[0065] (2) Pressure measurement: Provides pressure measurement function to ensure that the equipment can work normally under various pressure conditions.

[0066] (3) Temperature and humidity measurement: Built-in temperature and humidity sensors automatically compensate for gas temperature and humidity to ensure high accuracy of flow measurement.

[0067] (4) Oxygen concentration measurement: Measure oxygen concentration to ensure that the gas composition meets medical standards.

[0068] The first target flow rate value and the first target pressure difference value can be obtained in a specific mode.

[0069] The second target flow rate value is the flow rate value of the target ventilator at different rotation speeds.

[0070] The second target pressure difference value is the pressure difference value at different speeds of the target ventilator.

[0071] The second target flow rate value and the second target pressure difference value are usually obtained during the power-on self-test process; specifically, the above step 110 may include the following steps:

[0072] During the power-on self-test process of the target ventilator, a second target flow rate value and a second target pressure difference value at each target rotation speed point output by the target ventilator are obtained.

[0073] Among them, the flow rate value at a fixed speed is fixed; therefore, the second target flow rate value at each target speed point of the target ventilator is fixed, and the second target pressure difference value can be obtained by recording the pressure difference value of the pressure difference flow sensor at this time.

[0074] Exemplarily, y target speed points are output to obtain the second target flow rate value FLOW2 = {flow1, flow2, flow3, ... flow y} and the second target pressure difference value AD2 = {ad1, ad2, ad3, ... ad y}.

[0075] Step 120: Fit the first target flow rate value and the first target pressure difference value at different target gas temperatures to obtain a target gas temperature compensation coefficient.

[0076] The first target flow rate value and the first target pressure difference value at different target gas temperatures may be fitted by a mathematical model; specifically, the above step 120 may include the following steps:

[0077] For the first target flow rate values ​​and the first target pressure difference values ​​at different target gas temperatures, a target mathematical model is established. The first target flow rate values ​​and the first target pressure difference values ​​at different target gas temperatures are fitted according to the target mathematical model to obtain the target gas temperature compensation coefficient. The target mathematical model is shown in the following formula (1):

[0078] f(x,y)=a*x+b*y+c (1)

[0079] Wherein, a, b, and c represent the target gas temperature compensation coefficients; x and y represent the first target flow rate value and the first target pressure difference value at different target gas temperatures; and f(x, y) represents the fitting result.

[0080] For example, for different target gas temperatures T={T1, T2, T3, ...... T m} and the first target flow rate value and the first target pressure difference value {FLOW1,AD1}, {FLOW2,AD2},........{FLOW m,AD m}Establish the target mathematical model f(x,y)=a*x+b*y+c between T, FLOW and AD; according to the target mathematical model, obtain the functional correspondence between the flow rate value, gas temperature and pressure difference value FLOW=Function1(TAD1) and the three-dimensional surface data fitting parameters, which are the above-mentioned target gas temperature compensation coefficients.

[0081] Step 130: Determine a target flow rate compensation difference according to the target gas temperature compensation coefficient, the second target pressure difference value, and the second target flow rate value.

[0082] The target flow rate compensation difference is obtained by the flow rate value of the second target flow rate value and the second target pressure difference value under the target gas temperature compensation coefficient; specifically, Figure 4 As shown, the above step 130 may include the following steps 410 and 420:

[0083] Step 410: Determine a third target flow rate value corresponding to the second target pressure difference value according to the target gas temperature compensation coefficient.

[0084] For example, according to the second target pressure difference value AD2={ad1, ad2, ad3, ... ad y} and the target gas temperature compensation coefficient, determine the third target flow rate value Flow_Calc under the second target pressure difference value = {flow1_calc, flow2_calc, flow3_calc, ... flow y _calc}.

[0085] Step 420: Determine a target flow rate compensation difference according to the third target flow rate value and the second target flow rate value.

[0086] The target flow rate compensation difference delta_flow = Flow - Flow_Calc = {flow1_delta, flow2_delta, flow3_delta, ... flow y _delta}.

[0087] Step 140: Fit the target flow rate compensation difference and the second target pressure difference value to obtain a target flow rate compensation coefficient.

[0088] Among them, the fitting model f(z)=d*z is established between the target flow rate compensation difference and the second target pressure difference value. g+e; wherein, d, g, e represent target flow rate compensation coefficients; z represents the second target pressure difference value; f(z) represents the target flow rate compensation difference; according to the fitting, the functional correspondence between the target flow rate compensation difference value and the second target pressure difference value delta_flow = Function2 (Ad2) and the fitting parameters are obtained, and the fitting parameters are the above-mentioned target flow rate compensation coefficients.

[0089] Step 150: During the ventilation process of the target ventilator, obtain the current gas temperature and the current pressure difference value, and determine the target compensated flow rate according to the current gas temperature, the current pressure difference value, the target flow rate compensation coefficient, and the target gas temperature compensation coefficient.

[0090] Among them, this step is to calculate two compensation flow rates through the current gas temperature, the current pressure difference value, the target flow rate compensation coefficient, and the target gas temperature compensation coefficient, and then obtain the final target compensation flow rate through these two compensation flow rates; specifically, Figure 5 As shown, the above step 150 may include the following steps 510 to 530:

[0091] Step 510: Determine the target temperature compensated flow rate according to the current gas temperature, the current pressure difference value, and the target gas temperature compensation coefficient.

[0092] Among them, based on the functional correspondence between the flow rate value, gas temperature, and pressure difference value FLOW=Function1(TAD1), the target temperature compensated flow (flow rate, i.e. flow rate) Flow_temper=Function1(T,AD1) is determined according to the current gas temperature, the current pressure difference value, and the target gas temperature compensation coefficient.

[0093] Step 520: Determine the target flow rate compensation flow rate according to the current gas temperature, the current pressure difference value, and the target flow rate compensation coefficient.

[0094] Among them, based on the functional correspondence between the target flow rate compensation difference and the second target pressure difference value delta_flow=Function2(Ad2), according to the current pressure difference value and the target flow rate compensation coefficient, the target flow rate compensation flow (flow rate, i.e. flow rate) Flow_start=Function2(AD2) is determined.

[0095] Step 530: Determine a target compensation flow rate according to the target temperature compensation flow rate and the target flow velocity compensation flow rate.

[0096] The sum of the target temperature compensated flow rate and the target flow velocity compensated flow rate is determined as the target compensated flow rate Flow=Flow_temper+Flow_start.

[0097] The flow compensation method of the differential pressure flow sensor provided in the embodiment of the present application first obtains the first target flow rate value and the first target pressure difference value at different target gas temperatures for the target ventilator; obtains the second target flow rate value and the second target pressure difference value at each target speed point output by the target ventilator; secondly, fits the first target flow rate value and the first target pressure difference value at different target gas temperatures to obtain the target gas temperature compensation coefficient; thirdly, determines the target flow rate compensation difference according to the target gas temperature compensation coefficient, the second target pressure difference value, and the second target flow rate value; then, fits the target flow rate compensation difference and the second target pressure difference value to obtain the target flow rate compensation coefficient; finally, during the ventilation process of the target ventilator, obtains the current gas temperature and the current pressure difference value, and determines the target compensated flow according to the current gas temperature, the current pressure difference value, the target flow rate compensation coefficient, and the target gas temperature compensation coefficient. In this way, by obtaining data tables of pressure difference values ​​and true flow rate values ​​at multiple temperatures, performing three-dimensional data fitting on the data tables, and obtaining a fitting surface of the true flow rate, temperature, and pressure difference value of the pressure difference flow sensor, the gas flow rate at the current ambient temperature can be accurately calculated; in addition, the ventilator can self-correct the flow rate measurement error each time it is powered on for self-test, and can accurately measure the flow through the pressure difference sensor; through the dual flow compensation mechanism, the problem of inaccurate flow measurement of the pressure difference flow sensor at different gas temperatures can be solved, without the need for additional devices or sensors, the sensor has a simple structure and is reusable, and can repeatedly compensate and correct when a flow rate deviation occurs in the sensor; compared with other highly integrated flow sensors, the present application is lower in cost than other sensors, and has obvious cost advantages.

[0098] After introducing the flow compensation method of the differential pressure flow sensor according to the exemplary embodiment of the present disclosure, next, reference is made to Figure 6 A ventilator 600 according to an exemplary embodiment of the present disclosure will be described.

[0099] refer to Figure 6 , Ventilator 600, including:

[0100] Flow device 610;

[0101] The air outlet 620 of the flow device 610 is connected to the breathing circuit 630 and the main control chip 640; the main control chip 640 is connected to the first pressure sensor 650, the second pressure sensor 660 and the flow sensor 670; the flow sensor 670 is arranged at the front end of the air outlet 620; the first pressure sensor 650 is arranged on the side of the breathing circuit 630 close to the flow device 610; the second pressure sensor 660 is arranged on the side of the breathing circuit 630 away from the flow device 610 through the pressure collection tube 680; the side of the breathing circuit 630 away from the flow device 610 is connected to the breathing interface 690.

[0102] After introducing the ventilator of the exemplary embodiment of the present disclosure, next, reference is made to Figure 7 A flow compensation device 700 of a differential pressure flow sensor according to an exemplary embodiment of the present disclosure will be described.

[0103] refer to Figure 7 , a flow compensation device 700 of a differential pressure flow sensor, comprising:

[0104] The acquisition module 710 is configured to acquire, for a target ventilator, a first target flow rate value and a first target pressure difference value at different target gas temperatures; and acquire a second target flow rate value and a second target pressure difference value at each target speed point output by the target ventilator;

[0105] A first fitting module 720 is configured to fit the first target flow rate value and the first target pressure difference value at different target gas temperatures to obtain a target gas temperature compensation coefficient;

[0106] The first determination module 730 is configured to determine a target flow rate compensation difference value according to a target gas temperature compensation coefficient, a second target pressure difference value, and a second target flow rate value;

[0107] The second fitting module 740 is configured to fit the target flow rate compensation difference and the second target pressure difference value to obtain a target flow rate compensation coefficient;

[0108] The second determination module 750 is configured to obtain the current gas temperature and the current pressure difference value during the ventilation process of the target ventilator, and determine the target compensated flow rate according to the current gas temperature, the current pressure difference value, the target flow rate compensation coefficient, and the target gas temperature compensation coefficient.

[0109] In one embodiment, the acquisition module 710 is configured to: determine a target data point set based on a target flow range of a target ventilator; and for each target data point in the target data point set, obtain a first target flow rate value and a first target pressure difference value at different target gas temperatures.

[0110] In one implementation, the acquisition module 710 is configured to: divide the target flow range of the target ventilator into a plurality of target data points, and determine a target data point set according to the plurality of target data points.

[0111] In one embodiment, the acquisition module 710 is configured to: acquire the first target flow rate value and the first target pressure difference value at different target gas temperatures through a gas metering and calibration device.

[0112] In one embodiment, the acquisition module 710 is configured to: during the power-on self-test process of the target ventilator, acquire the second target flow rate value and the second target pressure difference value at each target speed point output by the target ventilator.

[0113] In one embodiment, the first fitting module 720 is configured to: establish a target mathematical model for the first target flow rate values ​​and the first target pressure difference values ​​at different target gas temperatures, and fit the first target flow rate values ​​and the first target pressure difference values ​​at different target gas temperatures according to the target mathematical model to obtain a target gas temperature compensation coefficient; the target mathematical model is shown in the following formula:

[0114] f(x,y)=a*x+b*y+c

[0115] Wherein, a, b, and c represent the target gas temperature compensation coefficients; x and y represent the first target flow rate value and the first target pressure difference value at different target gas temperatures; and f(x, y) represents the fitting result.

[0116] In one embodiment, the first determination module 730 is configured to: determine a third target flow rate value corresponding to the second target pressure difference value according to the target gas temperature compensation coefficient; and determine a target flow rate compensation difference value according to the third target flow rate value and the second target flow rate value.

[0117] In one embodiment, the second determination module 750 is configured to: determine the target temperature compensated flow rate based on the current gas temperature, the current pressure difference value, and the target gas temperature compensation coefficient; determine the target flow rate compensated flow rate based on the current gas temperature, the current pressure difference value, and the target flow rate compensation coefficient; determine the target compensated flow rate based on the target temperature compensated flow rate and the target flow rate compensated flow rate.

[0118] The above-mentioned device is used to execute the method provided by the aforementioned embodiment, and its implementation principle and technical effect are similar, which will not be repeated here.

[0119] The above modules may be one or more integrated circuits configured to implement the above methods, such as one or more application specific integrated circuits (ASICs), or one or more microprocessors, or one or more field programmable gate arrays (FPGAs). For another example, when a module is implemented in the form of a processing element scheduling program code, the processing element may be a general-purpose processor, such as a central processing unit (CPU) or other processor that can call program code. For another example, these modules may be integrated together and implemented in the form of a system-on-a-chip (SOC).

[0120] Figure 8A schematic diagram of a computer device provided in an embodiment of the present application. The device can be integrated into a terminal device or a chip of a terminal device. The terminal can be a computing device with data processing capabilities.

[0121] The device includes: a processor 801 , a storage medium 802 and a bus 803 .

[0122] The storage medium 802 stores program instructions executable by the processor 801. When the computer device 800 is running, the processor 801 communicates with the storage medium 802 via the bus 803. The processor 801 executes the program instructions to perform the above method embodiment. The specific implementation method and technical effect are similar and will not be repeated here.

[0123] Optionally, the present invention also provides a program product, such as a computer-readable storage medium, comprising a program, which is used to execute the above method embodiment when executed by a processor.

[0124] In the several embodiments provided by the present invention, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0125] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0126] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of hardware plus software functional units.

[0127] The above-mentioned integrated unit implemented in the form of a software functional unit can be stored in a computer-readable storage medium. The above-mentioned software functional unit is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor (English: processor) to perform some steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (English: Read-Only Memory, abbreviated: ROM), random access memory (English: Random Access Memory, abbreviated: RAM), disk or optical disk and other media that can store program codes.

[0128] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A flow compensation method for a differential pressure flow sensor, characterized in that: include: For a target ventilator, obtaining a first target flow rate value and a first target pressure difference value at different target gas temperatures; Obtaining a second target flow rate value and a second target pressure difference value at each target speed point output by the target ventilator; Fitting the first target flow rate value and the first target pressure difference value at different target gas temperatures to obtain a target gas temperature compensation coefficient; determining a target flow rate compensation difference value according to the target gas temperature compensation coefficient, the second target pressure difference value, and the second target flow rate value; Fitting the target flow rate compensation difference and the second target pressure difference value to obtain a target flow rate compensation coefficient; During the ventilation process of the target ventilator, the current gas temperature and the current pressure difference value are obtained, and the target compensated flow rate is determined according to the current gas temperature, the current pressure difference value, the target flow rate compensation coefficient, and the target gas temperature compensation coefficient.

2. The method according to claim 1, characterized in that The obtaining of the first target flow rate value and the first target pressure difference value at different target gas temperatures includes: Determining a target data point set according to a target flow range of the target ventilator; For each target data point in the target data point set, the first target flow rate value and the first target pressure difference value at different target gas temperatures are obtained.

3. The method according to claim 2, characterized in that Determining a target data point set according to a target flow range of the target ventilator includes: The target flow range of the target ventilator is divided into a plurality of target data points, and the target data point set is determined according to the plurality of target data points.

4. The method according to claim 1, characterized in that: The obtaining of the first target flow rate value and the first target pressure difference value at different target gas temperatures includes: The first target flow rate value and the first target pressure difference value at different target gas temperatures are obtained through gas metering and calibration equipment.

5. The method according to claim 1, characterized in that The step of obtaining a second target flow rate value and a second target pressure difference value at each target speed point output by the target ventilator includes: During the power-on self-test process of the target ventilator, the second target flow rate value and the second target pressure difference value at each target rotation speed point output by the target ventilator are obtained.

6. The method according to claim 1, characterized in that The fitting of the first target flow rate value and the first target pressure difference value at different target gas temperatures to obtain a target gas temperature compensation coefficient includes: A target mathematical model is established for the first target flow rate values ​​and the first target pressure difference values ​​at different target gas temperatures, and the first target flow rate values ​​and the first target pressure difference values ​​at different target gas temperatures are fitted according to the target mathematical model to obtain the target gas temperature compensation coefficient; the target mathematical model is shown in the following formula: f(x,y)=a*x+b*y+c Wherein, a, b, and c represent the target gas temperature compensation coefficients; x and y represent the first target flow rate value and the first target pressure difference value at different target gas temperatures; and f(x, y) represents the fitting result.

7. The method according to claim 1, characterized in that The step of determining the target flow rate compensation difference value according to the target gas temperature compensation coefficient, the second target pressure difference value, and the second target flow rate value comprises: determining a third target flow rate value corresponding to the second target pressure difference value according to the target gas temperature compensation coefficient; The target flow rate compensation difference is determined according to the third target flow rate value and the second target flow rate value.

8. The method according to claim 1, characterized in that The determining the target compensation flow rate according to the current gas temperature, the current pressure difference value, the target flow rate compensation coefficient, and the target gas temperature compensation coefficient includes: Determining a target temperature compensated flow rate according to the current gas temperature, the current pressure difference value, and the target gas temperature compensation coefficient; Determining a target flow rate compensation flow rate according to the current gas temperature, the current pressure difference value, and the target flow rate compensation coefficient; The target compensated flow rate is determined according to the target temperature compensated flow rate and the target flow velocity compensated flow rate.

9. A flow compensation device for a differential pressure flow sensor, characterized in that: include: An acquisition module is configured to acquire, for a target ventilator, a first target flow rate value and a first target pressure difference value at different target gas temperatures; Obtaining a second target flow rate value and a second target pressure difference value at each target speed point output by the target ventilator; A first fitting module is configured to fit the first target flow rate value and the first target pressure difference value at different target gas temperatures to obtain a target gas temperature compensation coefficient; A first determination module is configured to determine a target flow rate compensation difference value according to the target gas temperature compensation coefficient, the second target pressure difference value, and the second target flow rate value; A second fitting module is configured to fit the target flow rate compensation difference and the second target pressure difference value to obtain a target flow rate compensation coefficient; The second determination module is configured to obtain the current gas temperature and the current pressure difference value during the ventilation process of the target ventilator, and determine the target compensated flow rate based on the current gas temperature, the current pressure difference value, the target flow rate compensation coefficient, and the target gas temperature compensation coefficient.

10. A ventilator, characterized in that: include: Flow devices; The air outlet of the flow device is connected to a breathing circuit and a main control chip; the main control chip is connected to a first pressure sensor, a second pressure sensor and a flow sensor; the flow sensor is arranged at the front end of the air outlet; the first pressure sensor is arranged on a side of the breathing circuit close to the flow device; the second pressure sensor is arranged on a side of the breathing circuit away from the flow device through a pressure collection tube; and a breathing interface is connected to the side of the breathing circuit away from the flow device.

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