Oxygen generator flow automatic control method and system

Abstract

The application relates to the technical field of oxygen flow control of an oxygen generator, and discloses an oxygen generator flow automatic control method and system, an oxygen generator flow automatic control method, which comprises the following steps: configuring a target oxygen configuration flow and a target oxygen concentration required by target personnel; acquiring actual oxygen flow and actual oxygen concentration in real time; calculating an effective oxygen uptake deviation; when the effective oxygen uptake deviation is not lower than a specified oxygen uptake, dynamically acquiring a short-time oxygen configuration flow; generating a flow control signal through a preset PID control algorithm based on the deviation between the short-time oxygen configuration flow and the actual oxygen flow; and driving a flow adjustment actuator to output oxygen according to the flow control signal; a first parameter group is adopted during an inhalation phase of the target personnel, and a second parameter group is adopted during an exhalation phase of the target personnel, wherein, and, the response delay of the patient during a rapid inhalation phase is reduced, the oxygen waste during the exhalation phase is reduced, and the method is especially suitable for irregular breathing modes of COPD patients.

Description

Technical Field

[0001] This application relates to the technical field of oxygen flow control for oxygen generators, and in particular to an automatic flow control method and system for oxygen generators. Background Technology

[0002] As people's living standards continue to improve, their demand for health is gradually increasing. Oxygen inhalation will gradually become a means of home and community rehabilitation. Oxygen concentrators are used for oxygen supplementation and inhalation in both leisure and medical fields. An oxygen concentrator draws air into a compressor through an intake pipe, which generates compressed air. Then, using molecular sieve physical adsorption and desorption technology, nitrogen in the air is adsorbed during pressurization. The remaining unabsorbed oxygen is collected and purified to become high-purity oxygen. Specifically, the compressed air is purified by an air purification dryer and then enters an adsorption tower through a switching valve. Inside the adsorption tower, nitrogen is adsorbed by molecular sieves, and oxygen is accumulated before entering an oxygen storage tank. Finally, it is filtered through odor removal, dust removal, and sterilization filters to obtain qualified medical oxygen.

[0003] Oxygen therapy is also the most common way to correct hypoxia in clinical practice. While it improves symptoms, too low a concentration may not alleviate the hypoxia, while too high a concentration may lead to oxygen toxicity. Current oxygen concentrators can only provide one concentration (greater than 90%) of oxygen and cannot directly adjust the concentration to suit the patient's needs. Existing oxygen concentrators generally use flow control schemes with rotor flowmeters or solenoid valves with micro-orifices. However, rotor flowmeter adjustment is mechanical, cumbersome, and inaccurate; solenoid valves with micro-orifices only allow for fixed flow rate levels, not continuous adjustment, and are also costly. Summary of the Invention

[0004] In order to provide a low-cost method and system for automatic control of oxygen generator flow rate with precise adjustable oxygen concentration, this application provides a method and system for automatic control of oxygen generator flow rate.

[0005] In a first aspect, this application provides an automatic flow control method for an oxygen concentrator, employing the following technical solution:

[0006] An automatic flow control method for an oxygen concentrator, the automatic flow control method comprising:

[0007] Configure the target oxygen flow rate required for the target personnel. and target oxygen concentration ;

[0008] Real-time acquisition of actual oxygen flow and actual oxygen concentration ;

[0009] Calculate the effective oxygen uptake deviation When the effective oxygen uptake deviates When not lower than the specified oxygen uptake Dynamically obtain short-term oxygen configuration flow rate ;

[0010] Based on the short-time oxygen configuration flow rate With the actual oxygen flow rate The deviation is used to generate a flow control signal through a preset PID control algorithm. ;

[0011] The flow control signal drives the flow regulating actuator to output oxygen.

[0012] During the configuration process, the PID control algorithm uses the first parameter set during the inhalation phase of the target person. The second parameter set is used during the expiratory phase of the target person. ,in, , .

[0013] By adopting the above technical solution, the effective oxygen uptake deviation is calculated by real-time monitoring of actual oxygen flow and actual oxygen concentration, and the target flow is adjusted. Then, PID control is executed based on the adjusted target flow, which can fundamentally solve the problem of insufficient oxygen uptake caused by oxygen concentration fluctuations in traditional oxygen concentrators. When the performance of molecular sieve deteriorates and the oxygen concentration decreases, this solution can still maintain the deviation between the patient's actual oxygen uptake and the set value within an acceptable value, significantly improving the treatment safety of patients with chronic respiratory diseases and avoiding the risk of decreased blood oxygen saturation caused by sudden concentration fluctuations. Moreover, the dual-group PID parameter strategy with respiratory phase adaptation increases the proportional coefficient and decreases the integral coefficient in the inspiratory phase and adjusts it in the opposite way in the expiratory phase, reducing the response delay in the rapid inhalation phase and reducing oxygen waste in the expiratory phase. It is especially suitable for the irregular breathing patterns of COPD patients.

[0014] Optionally, the PID control algorithm includes:

[0015]

[0016] in, , Configure the current oxygen flow rate and output. The oxygen emission frequency that drives the flow regulating actuator Traversing from system startup up to the current moment All points in time, This represents each historical figure The flow deviation value corresponding to the time.

[0017] By adopting the above technical solution, the target oxygen configuration flow rate is maintained when the effective oxygen uptake deviation meets the requirements. Keeping it unchanged can reduce fluctuations in oxygen regulation and achieve the goal of not increasing the regulation intensity unnecessarily.

[0018] Optionally, the calculation of effective oxygen uptake deviation include:

[0019]

[0020] like Configure flow rate according to the target oxygen level. Execute the PID control algorithm; otherwise, maintain the target oxygen configuration flow rate. .

[0021] Optionally, a first-order differential calculation is performed on the flow sensor signal, and the intake is determined to begin when the differential value exceeds the threshold three times consecutively.

[0022] Optionally, the short-time oxygen configuration flow rate The configuration method is as follows:

[0023]

[0024] in, This is an adjustment coefficient, which is dynamically related to the working status evaluation score of the adjustment actuator.

[0025] Optionally, the oxygen generator includes an oxygen generating unit, a first pressure limiting valve, an elastic one-way gas outlet core, a first gas delivery pipe, a water injection observation bottle, a second gas delivery pipe, and a second pressure limiting valve, which are connected in sequence.

[0026] The elastic one-way air outlet core includes a cylindrical elastic body. An air outlet slit is opened at one end of the cylindrical elastic body near the air supply pipe. The two opposite seam surfaces of the air outlet slit are tightly sealed against each other. An air inlet channel is opened at one end of the cylindrical elastic body near the pressure limiting valve. A compression chamber is opened between the air inlet channel and the air outlet slit.

[0027] The cylindrical elastomer is provided with a micro drive motor and a compression part fixed to the output end of the micro drive motor. The micro drive motor drives the compression part to rotate, intermittently compressing the compression chamber.

[0028] Optionally, the work status evaluation score The methods for obtaining the information include:

[0029]

[0030] Get within a specified time period, The actual amount of air bubbles produced in the water-filled observation bottle. This refers to the actual average speed of the micro drive motor. This is the theoretical bubble output corresponding to the actual average rotational speed. The theoretical average rotational speed corresponding to the actual amount of bubbles produced.

[0031] Optionally, the oxygen generator includes a compensation unit connected to the micro drive motor for controlling the extrusion stroke of the extrusion section on the cylindrical elastomer;

[0032] When the work status assessment score If the score is higher than the specified value, adjust the extrusion stroke until the working state evaluation score is reached. Less than or equal to the specified score.

[0033] Secondly, this application provides an automatic flow control system for an oxygen concentrator, which adopts the following technical solution:

[0034] An automatic flow control system for an oxygen concentrator, the automatic flow control system comprising:

[0035] The configuration module is used to configure the target oxygen flow rate required by the target personnel upon restarting. and target oxygen concentration ;

[0036] The data acquisition module is used to obtain the actual oxygen flow rate in real time. and actual oxygen concentration ;

[0037] Microcontroller used to calculate effective oxygen uptake deviation When the effective oxygen uptake deviates When not lower than the specified oxygen uptake Dynamically obtain short-term oxygen configuration flow rate ;

[0038] Based on the short-time oxygen configuration flow rate With the actual oxygen flow rate The deviation is used to generate a flow control signal through a preset PID control algorithm. ;

[0039] The flow control signal drives the flow regulating actuator to output oxygen.

[0040] During the configuration process, the PID control algorithm uses the first parameter set during the inhalation phase of the target person. The second parameter set is used during the expiratory phase of the target person. ,in, , .

[0041] In summary, this application includes at least one of the following beneficial technical effects:

[0042] 1. By real-time monitoring of actual oxygen flow rate and actual oxygen concentration to calculate the deviation of effective oxygen uptake, the target flow rate is adjusted, and PID control is executed based on the adjusted target flow rate. This fundamentally solves the problem of insufficient oxygen uptake caused by oxygen concentration fluctuations in traditional oxygen concentrators. When the performance of molecular sieve deteriorates and the oxygen concentration decreases, this solution can still maintain the deviation between the patient's actual oxygen uptake and the set value within an acceptable range, significantly improving the treatment safety of patients with chronic respiratory diseases and avoiding the risk of decreased blood oxygen saturation caused by sudden concentration fluctuations. Moreover, it adopts a dual-group PID parameter strategy with adaptive respiratory phase, increasing the proportional coefficient and decreasing the integral coefficient in the inspiratory phase, and adjusting in the opposite direction in the expiratory phase to reduce the response delay during the patient's rapid inhalation phase and reduce oxygen waste during the expiratory phase. It is especially suitable for the irregular breathing patterns of COPD patients.

[0043] 2. The inspiratory phase identification method based on the first-order difference of the flow signal determines the respiratory phase transition point by detecting three consecutive sampling values ​​exceeding the threshold. This method can accurately capture the respiratory phase transition point without the need for an additional respiratory sensor, thus reducing hardware costs. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the automatic flow control method for an oxygen concentrator in this application;

[0045] Figure 2 This is a schematic diagram of the oxygen flow direction and the principle structure connection of the oxygen generator in this application;

[0046] Figure 3 This is a cross-sectional view of the first pressure limiting valve structure of the oxygen generator in this application;

[0047] Figure 4 This is a cross-sectional view of the elastic unidirectional air outlet core structure of the oxygen generator in this application.

[0048] Reference numerals: 1. First pressure relief valve; 2. Cylindrical elastomer; 3. Air outlet; 4. Extrusion chamber; 5. Sealing protrusion. Detailed Implementation

[0049] The embodiments of this application are described in detail below, and examples of the embodiments are shown in the accompanying drawings.

[0050] In the description of this specification, the references to "certain embodiments," "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples" refer to specific features, structures, materials, or characteristics described in connection with the described embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0051] This application discloses an automatic flow control method for an oxygen concentrator, referring to... Figure 1 ,include:

[0052] Configure the target oxygen flow rate required for the target personnel. and target oxygen concentration ;

[0053] Real-time acquisition of actual oxygen flow and actual oxygen concentration ;

[0054] Calculate the effective oxygen uptake deviation When the effective oxygen uptake deviates When not lower than the specified oxygen uptake Dynamically obtain short-term oxygen configuration flow rate ;

[0055] Based on the short-time oxygen configuration flow rate With the actual oxygen flow rate The deviation is used to generate a flow control signal through a preset PID control algorithm. ;

[0056] The flow control signal drives the flow regulating actuator to output oxygen.

[0057] In this embodiment of the application, the specific operation is as follows:

[0058] Initialization settings: The user inputs the desired target oxygen flow rate. and target oxygen concentration The initial PID parameters, proportional coefficients, are loaded via a microcontroller (such as an STM32F407 microcontroller running an adaptive PID algorithm). Integral coefficient Differential coefficients ;

[0059] Real-time data acquisition: Actual oxygen flow rate is obtained using a thermal mass flow meter (model SFM3000, measurement range 0-20 L / min, accuracy ±2%). (Unit: L / min) The actual oxygen concentration is obtained through an electrochemical oxygen sensor (model O2-A2, range 0-100%, accuracy ±1.5%). (unit:%);

[0060] Calculate the effective oxygen uptake deviation The unit is mL / min·%:

[0061]

[0062] like Configure flow rate according to the target oxygen level. Execute the PID control algorithm; otherwise, maintain the target oxygen configuration flow rate. When the effective oxygen uptake deviation meets the requirements, maintain the target oxygen configuration flow rate. Keeping it unchanged can reduce fluctuations in oxygen regulation and achieve the goal of not increasing the regulation intensity unnecessarily.

[0063] Dynamically configure short-term oxygen flow rate The short-time oxygen configuration flow rate The configuration method is as follows:

[0064]

[0065] in, The adjustment coefficient is dynamically related to the working status evaluation score of the adjustment actuator. When the working status evaluation score is less than the specified score, it is configured to be 1. Otherwise, it is adjusted according to the comparison result of oxygen output and expected value. If the oxygen output is higher than the expected value, the adjustment coefficient can be reduced; otherwise, it can be increased.

[0066] Generated based on PID control algorithm :

[0067]

[0068] in, , Configure the current oxygen flow rate and output. The oxygen emission frequency that drives the flow regulating actuator Traversing from system startup up to the current moment All points in time, This represents each historical figure The flow deviation value corresponding to the time.

[0069] During the inspiratory phase identification process, the actual oxygen flow rate is... The signal is subjected to first-order differential calculation, and inhalation is determined to begin when the differential value exceeds the threshold three times in a row.

[0070] In this embodiment, during the configuration process, the PID control algorithm uses an aggressive parameter set during the inhalation phase of the target person. This reduces the integral effect and prevents excessive accumulation of the integral term during a rapid increase in flow rate, which could lead to overshoot oscillations. A second parameter set is used during the expiratory phase of the target individual. It enhances the integral effect, quickly eliminates residual deviations during the expiratory phase, strengthens the ability to suppress small flow deviations during the expiratory phase, and can reduce oxygen flow by about 20% during the expiratory phase, thus reducing oxygen waste.

[0071] By calculating the effective oxygen uptake deviation through real-time monitoring of actual oxygen flow and concentration, the target flow is adjusted, and PID control is executed based on the adjusted target flow. This fundamentally solves the problem of insufficient oxygen uptake caused by oxygen concentration fluctuations in traditional oxygen concentrators. Even when the molecular sieve performance deteriorates and the oxygen concentration decreases, this solution can still maintain the deviation between the patient's actual oxygen uptake and the set value within an acceptable range, significantly improving the treatment safety of patients with chronic respiratory diseases and avoiding the risk of decreased blood oxygen saturation caused by sudden concentration fluctuations. Moreover, the dual-group PID parameter strategy with adaptive respiratory phase increases the proportional coefficient and decreases the integral coefficient during the inspiratory phase, while adjusting in the opposite direction during the expiratory phase. This reduces the response delay during the patient's rapid inhalation phase and reduces oxygen waste during the expiratory phase, making it particularly suitable for the irregular breathing patterns of COPD patients.

[0072] Specifically, such as Figure 2-4 As shown, the oxygen generator includes an oxygen generating unit, a first pressure limiting valve 1, an elastic one-way gas outlet core, a first gas delivery pipe, a water injection observation bottle, a second gas delivery pipe, and a second pressure limiting valve, which are connected in sequence.

[0073] The elastic one-way air outlet core includes a cylindrical elastomer 2 made of rubber. An air outlet slit 3 is opened at one end of the cylindrical elastomer 2 near the air supply pipe. The two opposite seam surfaces of the air outlet slit 3 are tightly sealed against each other. An air inlet channel is opened at one end of the cylindrical elastomer 2 near the pressure limiting valve. An extrusion chamber 4 is opened between the air inlet channel and the air outlet slit 3. A sealing protrusion 5 is integrally formed inside to improve oxygen delivery efficiency and prevent oxygen from backflushing the oxygen generating unit.

[0074] A micro-drive motor and a compression section fixed to the output end of the micro-drive motor are provided on the outer side of the cylindrical elastomer 2. The compression section can be a U-shaped rod and a compression column. The micro-drive motor drives the U-shaped rod to rotate the compression column. The compression column intermittently compresses the compression chamber 4, driving the sealing protrusion 5 to press against the upper surface of the compression chamber 4 at one end away from the air outlet 3. As the compression column rotates, it continuously compresses the oxygen flow, causing the oxygen flow to open the air outlet 3 and enter the water injection observation bottle through the first gas supply pipe. During the recovery process of the compression chamber 4, the internal air pressure decreases, and new oxygen refills the compression chamber 4 through the first pressure limiting valve 1. An image acquisition unit is provided on the side of the water injection observation bottle, which can be used to acquire the video stream of bubbles in the water injection observation bottle, send it to the corresponding recognition model for recognition, and count the bubbles. The recognition model used in this solution is trained based on an existing neural network model, which will not be elaborated here.

[0075] This design allows for precise adjustment of oxygen flow by controlling the speed of a micro-drive motor without the need for a solenoid valve with micro-orifices. It is also cost-effective and easy to replace and maintain. The second pressure relief valve can moderate the pulsed oxygen flow and deliver it to the user smoothly.

[0076] Optionally, the work status evaluation score The methods for obtaining the information include:

[0077]

[0078] Get within a specified time period, The actual amount of air bubbles produced in the water-filled observation bottle. This refers to the actual average speed of the micro drive motor. This is the theoretical bubble output corresponding to the actual average rotational speed. This is the theoretical average rotational speed corresponding to the actual bubble output. This scheme employs a two-way evaluation strategy, which can reduce the large errors that may be caused by evaluation from a single angle.

[0079] Optionally, the oxygen generator includes a compensation unit connected to the micro drive motor, used to control the extrusion stroke of the extrusion section on the cylindrical elastic body 2; the compensation unit can be operated by electromagnetic attraction or repulsion, or directly by worm gear drive, with the goal of achieving the movement of the micro drive motor perpendicular to the axis of the cylindrical elastic body 2.

[0080] When the work status assessment score When the score exceeds a specified value, which can be configured to 0.1, the extrusion stroke is adjusted until the working state evaluation score is reached. Less than or equal to the specified score.

[0081] This application also discloses an automatic flow control system for an oxygen concentrator, the automatic flow control system comprising:

[0082] The configuration module is used to configure the target oxygen flow rate required by the target personnel upon restarting. and target oxygen concentration ;

[0083] The data acquisition module is used to obtain the actual oxygen flow rate in real time. and actual oxygen concentration ;

[0084] Microcontroller used to calculate effective oxygen uptake deviation When the effective oxygen uptake deviates When not lower than the specified oxygen uptake Dynamically obtain short-term oxygen configuration flow rate ;

[0085] Based on the short-time oxygen configuration flow rate With the actual oxygen flow rate The deviation is used to generate a flow control signal through a preset PID control algorithm. ;

[0086] The flow control signal drives the flow regulating actuator to output oxygen.

[0087] During the configuration process, the PID control algorithm uses the first parameter set during the inhalation phase of the target person. The second parameter set is used during the expiratory phase of the target person. ,in, , .

[0088] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. An automatic flow control method for an oxygen concentrator, characterized in that, The automatic flow control method includes: Configure the target oxygen flow rate required for the target personnel. and target oxygen concentration ; Real-time acquisition of actual oxygen flow and actual oxygen concentration ; Calculate the effective oxygen uptake deviation When the effective oxygen uptake deviates When not lower than the specified oxygen uptake Dynamically obtain short-term oxygen configuration flow rate ; Based on the short-time oxygen configuration flow rate With the actual oxygen flow rate The deviation is used to generate a flow control signal through a preset PID control algorithm. ; The flow control signal drives the flow regulating actuator to output oxygen. During the configuration process, the PID control algorithm uses the first parameter set during the inhalation phase of the target person. The second parameter set is used during the expiratory phase of the target person. ,in, , ; The oxygen generator includes an oxygen generating unit, a first pressure limiting valve (1), an elastic one-way gas outlet core, a first gas delivery pipe, a water injection observation bottle, a second gas delivery pipe, and a second pressure limiting valve, which are connected in sequence. The elastic one-way air outlet core includes a cylindrical elastic body (2). An air outlet slit (3) is provided at one end of the cylindrical elastic body (2) near the air supply pipe. The two opposite seam surfaces of the air outlet slit (3) are sealed against each other. An air inlet channel is provided at one end of the cylindrical elastic body (2) near the pressure limiting valve. A compression chamber (4) is provided between the air inlet channel and the air outlet slit (3). The cylindrical elastomer (2) is provided with a micro drive motor and a pressing part fixed at the output end of the micro drive motor. The micro drive motor drives the pressing part to rotate and intermittently press the pressing chamber (4). Work status assessment score The methods for obtaining the information include: Get within a specified time period, The actual amount of air bubbles produced in the water-filled observation bottle. This refers to the actual average speed of the micro drive motor. This is the theoretical bubble output corresponding to the actual average rotational speed. The theoretical average rotational speed corresponding to the actual amount of bubbles produced.

2. The automatic flow control method for an oxygen concentrator according to claim 1, characterized in that, The PID control algorithm includes: in, , Configure the current oxygen flow rate and output. The oxygen emission frequency that drives the flow regulating actuator Traversing from system startup up to the current moment All points in time, This represents each historical figure The flow deviation value corresponding to the time.

3. The automatic flow control method for an oxygen concentrator according to claim 1, characterized in that, The calculation of effective oxygen uptake deviation include: like Configure flow rate according to the target oxygen level. Execute the PID control algorithm; otherwise, maintain the target oxygen configuration flow rate. .

4. The automatic flow control method for an oxygen concentrator according to claim 1, characterized in that, The method for identifying the inhalation phase is as follows: perform first-order differential calculation on the flow sensor signal, and determine the start of inhalation when the differential value exceeds the threshold three times consecutively.

5. The automatic flow control method for an oxygen concentrator according to claim 1, characterized in that, The short-time oxygen configuration flow rate The configuration method is as follows: in, This is an adjustment coefficient, which is dynamically related to the working status evaluation score of the adjustment actuator.

6. The automatic flow control method for an oxygen concentrator according to claim 1, characterized in that, The oxygen generator includes a compensation unit, which is connected to the micro drive motor and is used to control the extrusion stroke of the extrusion section on the cylindrical elastomer (2). When the work status assessment score If the score is higher than the specified value, adjust the extrusion stroke until the working state evaluation score is reached. Less than or equal to the specified score.

7. An automatic flow control system for an oxygen concentrator, comprising the automatic flow control method for an oxygen concentrator as described in any one of claims 1-6, characterized in that, The automatic flow control system includes: The configuration module is used to configure the target oxygen flow rate required by the target personnel upon restarting. and target oxygen concentration ; The data acquisition module is used to obtain the actual oxygen flow rate in real time. and actual oxygen concentration ; Microcontroller used to calculate effective oxygen uptake deviation When the effective oxygen uptake deviates When not lower than the specified oxygen uptake Dynamically obtain short-term oxygen configuration flow rate ; Based on the short-time oxygen configuration flow rate With the actual oxygen flow rate The deviation is used to generate a flow control signal through a preset PID control algorithm. ; The flow control signal drives the flow regulating actuator to output oxygen. During the configuration process, the PID control algorithm uses the first parameter set during the inhalation phase of the target person. The second parameter set is used during the expiratory phase of the target person. ,in, , .

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