Method and system for automatically controlling flow of oxygen generator

Abstract

The invention relates to the technical field of oxygenerator oxygen flow control, and discloses an oxygenerator flow automatic control method and system, the oxygenerator flow automatic control method comprises the following steps: configuring a target oxygen configuration flow # imgabs0 # and a target oxygen concentration # imgabs1 # required by a target person; the actual oxygen flow # imgabs2 # and the actual oxygen concentration # imgabs3 # are obtained in real time; the effective oxygen uptake deviation # imgabs4 # is calculated, and when the effective oxygen uptake deviation # imgabs5 # is not lower than the specified oxygen uptake deviation # imgabs6 #, the short-time oxygen configuration flow # imgabs7 # is dynamically obtained; based on the deviation between the short-time oxygen configuration flow # imgabs8 # and the actual oxygen flow # imgabs9 #, a flow control signal # imgabs10 # is generated through a preset PID control algorithm; driving a flow regulation actuator to output oxygen according to the flow control signal; a first parameter group # imgabs11 # is adopted in the inspiration phase period of a target person, a second parameter group # imgabs12 # is adopted in the expiration phase period of the target person, # imgabs13 # and # imgabs14 # are adopted, the response delay of the rapid inspiration stage of the patient is reduced, oxygen waste can be reduced in the expiration period, and the method is particularly suitable for the irregular breathing mode of the COPD patient.

Description

Technical Field

[0001] The present application relates to the technical field of oxygen flow control of an oxygen concentrator, and in particular to an automatic flow control method and system for an oxygen concentrator. Background Art

[0002] As people's living standards continue to improve, their demand for health is gradually increasing. Oxygen inhalation will gradually become a means of rehabilitation in families and communities. Oxygen concentrators are used for oxygen supplementation and inhalation in leisure, home, or medical settings. The oxygen concentrator draws air into the compressor through an intake pipe, which produces compressed air. It then uses molecular sieve physical adsorption and desorption technology to adsorb nitrogen from the air during pressurization. The remaining unabsorbed oxygen is collected and purified to become high-purity oxygen. The specific working process is that the compressed air is purified by an air purification dryer and then enters the adsorption tower through a switching valve. In the adsorption tower, nitrogen is adsorbed by the molecular sieve. Oxygen accumulates in the adsorption tower and enters the oxygen storage tank. It is then filtered through odor removal, dust removal filters, and sterilization filters to obtain qualified medical oxygen.

[0003] Oxygen inhalation is the most common clinical method for correcting hypoxia. While it improves hypoxia symptoms, too low a concentration can lead to persistent hypoxia, while too high a concentration can cause oxygen toxicity. Existing oxygen concentrators can only provide a single oxygen concentration (greater than 90%) and cannot directly adjust the oxygen concentration to suit the patient's needs. Existing oxygen concentrators typically use flow control solutions such as rotor flowmeters or solenoid valves with micropores. However, rotor flowmeter adjustment is mechanical, cumbersome, and inaccurate. Solenoid valves with micropores can only achieve fixed flow control, not continuous flow adjustment, and are relatively expensive. Summary of the Invention

[0004] In order to provide a low-cost oxygen concentrator flow automatic control method and system with accurately adjustable oxygen concentration, the present application provides an oxygen concentrator flow automatic control method and system.

[0005] In a first aspect, the present application provides an oxygen concentrator flow automatic control method, which adopts the following technical solution: An oxygen concentrator flow automatic control method, the flow automatic control method comprising: Configure the target oxygen flow rate required by the target personnel and target oxygen concentration ; Obtain actual oxygen flow in real time and actual oxygen concentration ; Calculating effective oxygen uptake deviation , when the effective oxygen uptake deviates Not less than the specified oxygen uptake , dynamically obtain short-term oxygen configuration flow ; Based on the short-term oxygen configuration flow The actual oxygen flow rate The deviation is used to generate flow control signal through the preset PID control algorithm ; driving a flow regulating actuator to output oxygen according to the flow control signal; During the configuration of the PID control algorithm, the target person adopts the first parameter group during the inhalation phase. , using the second parameter set during the exhalation phase of the target person ,in, , .

[0006] By adopting the above technical solution, the effective oxygen uptake deviation is calculated by real-time monitoring of the actual oxygen flow and actual oxygen concentration, the target flow is adjusted, and then PID control is performed based on the adjusted target flow. This can fundamentally solve the problem of insufficient oxygen uptake caused by oxygen concentration fluctuations in traditional oxygen concentrators. When the performance of the molecular sieve decays and the oxygen concentration decreases, this solution can still maintain the deviation between the patient's actual oxygen uptake and the set value less than the 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. In addition, a dual-group PID parameter strategy with respiratory phase adaptation is adopted to increase the proportional coefficient and reduce the integral coefficient in the inspiratory phase, and reverse the adjustment in the expiratory phase, reducing the response delay of the patient's rapid inhalation stage, and reducing oxygen waste in the expiratory period. It is especially suitable for the irregular breathing pattern of COPD patients.

[0007] Optionally, the PID control algorithm includes: in, , Configure the current oxygen flow rate and output driving the oxygen emission frequency of the flow regulating actuator, Traversal starts from the system To the current moment All time points, Represents every The flow deviation value corresponding to the moment.

[0008] By adopting the above technical solution, when the effective oxygen uptake deviation meets the requirements, the target oxygen configuration flow rate is maintained. Keeping it unchanged can reduce the fluctuations caused by oxygen regulation and achieve the goal of not expanding the regulation intensity unless necessary.

[0009] Optionally, the calculation of effective oxygen uptake deviation include: like , configure the flow rate according to the target oxygen Execute the PID control algorithm, otherwise maintain the target oxygen configuration flow .

[0010] Optionally, a first-order difference calculation is performed on the flow sensor signal, and the start of inhalation is determined when the difference value exceeds a threshold value three times in a row.

[0011] Optionally, the short-term oxygen configuration flow The configuration method is: in, is the adjustment coefficient, which is dynamically related to the working status evaluation score of the adjustment actuator.

[0012] Optionally, the oxygen concentrator includes an oxygen production unit, a first pressure-limiting valve, an elastic one-way gas outlet core, a first gas supply pipe, a water injection observation bottle, a second gas supply pipe and a second pressure-limiting valve, which are sequentially connected; The elastic one-way air outlet core comprises a cylindrical elastic body, an air outlet slit is formed at one end of the cylindrical elastic body close to the air delivery pipe, two opposite seam surfaces of the air outlet slit are tightly sealed against each other, an air inlet channel is formed at one end of the cylindrical elastic body close to the pressure limiting valve, and an extrusion chamber is formed between the air inlet channel and the air outlet slit; A micro drive motor and an extrusion portion fixed to an output end of the micro drive motor are provided on the outside of the cylindrical elastic body. The micro drive motor drives the extrusion portion to rotate and intermittently extrude the extrusion chamber.

[0013] Optionally, the work status assessment score The acquisition methods include: Get within the specified time period, is the actual amount of bubbles emitted from the water-filled observation bottle, is the actual average speed of the micro drive motor, is the theoretical bubble output corresponding to the actual average speed, is the theoretical average rotation speed corresponding to the actual bubble output.

[0014] Optionally, the oxygen concentrator includes a compensation unit, which is connected to the micro drive motor and is used to control the extrusion stroke of the extrusion part on the cylindrical elastic body; When the work status evaluation score When the score is higher than the specified value, the extrusion stroke is adjusted until the working state evaluation score is Less than or equal to the specified score.

[0015] In a second aspect, the present application provides an oxygen concentrator flow automatic control system, which adopts the following technical solution: An oxygen concentrator flow automatic control system, the flow automatic control system comprising: Configuration module, used to configure the target oxygen flow required by the target personnel at the beginning and target oxygen concentration ; Acquisition module, used to obtain actual oxygen flow in real time and actual oxygen concentration ; Microcontroller for calculating effective oxygen uptake deviation , when the effective oxygen uptake deviates Not less than the specified oxygen uptake , dynamically obtain short-term oxygen configuration flow ; Based on the short-term oxygen configuration flow The actual oxygen flow rate The deviation is used to generate flow control signal through the preset PID control algorithm ; driving a flow regulating actuator to output oxygen according to the flow control signal; During the configuration of the PID control algorithm, the target person adopts the first parameter group during the inhalation phase. , using the second parameter set during the exhalation phase of the target person ,in, , .

[0016] In summary, this application includes at least one of the following beneficial technical effects: 1. By real-time monitoring of the actual oxygen flow and actual oxygen concentration, the effective oxygen uptake deviation is calculated, the target flow is adjusted, and PID control is performed based on the adjusted target flow. This can fundamentally solve the problem of insufficient oxygen uptake caused by oxygen concentration fluctuations in traditional oxygen concentrators. When the molecular sieve performance decays 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. In addition, a dual-group PID parameter strategy with respiratory phase adaptation is adopted. The proportional coefficient is increased and the integral coefficient is reduced in the inspiratory phase, and the reverse adjustment is made in the expiratory phase, reducing the response delay of the patient's rapid inhalation stage and reducing oxygen waste in the expiratory period. It is especially suitable for the irregular breathing pattern of COPD patients.

[0017] 2. The inspiratory phase recognition method based on the first-order difference of the flow signal can accurately capture the respiratory phase transition point without the need for an additional respiratory sensor, reducing hardware costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the automatic flow control method of the oxygen concentrator in this application; Figure 2 This is a schematic diagram of the oxygen flow and principle structural connection of the oxygen concentrator in this application; Figure 3 This is a cross-sectional view of the structure of the first pressure limiting valve of the oxygen concentrator in this application; Figure 4 This is a cross-sectional view of the elastic one-way air outlet core structure of the oxygen concentrator in this application.

[0019] Figure numerals: 1. first pressure-limiting valve; 2. cylindrical elastic body; 3. air outlet gap; 4. extrusion chamber; 5. sealing protrusion. DETAILED DESCRIPTION

[0020] Embodiments of the present application are described in detail below, examples of which are illustrated in the accompanying drawings.

[0021] Throughout this specification, reference to the terms "certain embodiments," "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, the schematic representations 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 any one or more embodiments or examples.

[0022] The present application discloses an oxygen concentrator flow automatic control method, referring to Figure 1 ,include: Configure the target oxygen flow rate required by the target personnel and target oxygen concentration ; Obtain actual oxygen flow in real time and actual oxygen concentration ; Calculating effective oxygen uptake deviation , when the effective oxygen uptake deviates Not less than the specified oxygen uptake , dynamically obtain short-term oxygen configuration flow ; Based on the short-term oxygen configuration flow The actual oxygen flow rate The deviation is used to generate flow control signal through the preset PID control algorithm ; driving a flow regulating actuator to output oxygen according to the flow control signal; In this embodiment of the present application, the specific operations are as follows: Initialization setting: The user enters the target oxygen configuration flow required and target oxygen concentration , load the PID initial parameter proportional coefficient through the microcontroller (STM32F407 microcontroller can be used to run the adaptive PID algorithm) , integral coefficient , differential coefficient ; Real-time data collection: The actual oxygen flow rate is obtained through a thermal mass flow meter (model SFM3000, measuring range 0-20 L / min, accuracy ±2%) (Unit: L / min), the actual oxygen concentration is obtained through the electrochemical oxygen sensor (model O2-A2, range 0-100%, accuracy ±1.5%) (unit:%); Calculating effective oxygen uptake deviation , unit is mL / min·%: like , configure the flow rate according to the target oxygen Execute the PID control algorithm, otherwise maintain the target oxygen configuration flow ; When the effective oxygen uptake deviation meets the requirements, maintain the target oxygen configuration flow Keeping it unchanged can reduce the fluctuations caused by oxygen regulation and achieve the goal of not expanding the regulation intensity unless necessary.

[0023] Dynamically configure short-term oxygen flow , the short-term oxygen configuration flow The configuration method is: in, is the adjustment coefficient, which 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 1. Otherwise, it is adjusted according to the comparison result between the oxygen output and the expected value. If the oxygen output is higher than the expected value, the adjustment coefficient can be reduced, otherwise it can be increased.

[0024] Generated according to PID control algorithm : in, , Configure the current oxygen flow rate and output driving the oxygen emission frequency of the flow regulating actuator, Traversal starts from the system To the current moment All time points, Represents every The flow deviation value corresponding to the moment.

[0025] During the inspiratory phase identification process, the actual oxygen flow The first-order difference calculation is performed on the signal, and the start of inspiration is determined when the difference value exceeds the threshold three times in a row.

[0026] In this embodiment, during the configuration of the PID control algorithm, the target person adopts an aggressive parameter set during the inhalation phase. , which can reduce the integral effect and prevent the integral term from being excessively accumulated when the flow rate rises rapidly, resulting in overshoot oscillation. During the exhalation phase of the target person, the second parameter group is used. , enhance the integral effect, quickly eliminate the residual deviation during the exhalation period, and strengthen the ability to suppress small flow deviations during the exhalation period. In addition, it can reduce the oxygen flow by about 20% during the exhalation phase to reduce oxygen waste.

[0027] By real-time monitoring of the actual oxygen flow and actual oxygen concentration, calculating the effective oxygen uptake deviation, adjusting the target flow, and then executing PID control based on the adjusted target flow, the problem of insufficient oxygen uptake caused by oxygen concentration fluctuations in traditional oxygen concentrators can be fundamentally solved. When the performance of the molecular sieve decays and the oxygen concentration decreases, this solution can still maintain the deviation between the patient's actual oxygen uptake and the set value less than the 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. In addition, a dual-group PID parameter strategy with respiratory phase adaptation is adopted to increase the proportional coefficient and reduce the integral coefficient in the inspiratory phase, and reverse the adjustment in the expiratory phase, reducing the response delay of the patient's rapid inhalation stage, and reducing oxygen waste in the expiratory period. It is especially suitable for the irregular breathing pattern of COPD patients.

[0028] Specifically, such as Figure 2-4 As shown, the oxygen concentrator includes an oxygen production unit, a first pressure-limiting valve 1, an elastic one-way gas outlet core, a first gas supply pipe, a water injection observation bottle, a second gas supply pipe and a second pressure-limiting valve that are connected in sequence; The elastic one-way air outlet core comprises a cylindrical elastic body 2 made of rubber, an air outlet slit 3 is provided at one end of the cylindrical elastic body 2 close to the air delivery pipe, two opposite seam surfaces of the air outlet slit 3 are tightly sealed against each other, an air inlet channel is provided at one end of the cylindrical elastic body 2 close to the pressure limiting valve, an extrusion chamber 4 is provided between the air inlet channel and the air outlet slit 3, and a sealing protrusion 5 is integrally formed therein to improve the oxygen delivery efficiency and prevent oxygen from backflowing into the oxygen production unit; A micro-drive motor and an extrusion part fixed to the output end of the micro-drive motor are provided on the outside of the cylindrical elastomer 2. The extrusion part can adopt a U-shaped rod and an extrusion column. The micro-drive motor drives the U-shaped rod to drive the extrusion column to rotate. The extrusion column intermittently squeezes the extrusion chamber 4 to drive the sealing protrusion 5 away from the end of the air outlet slit 3 to be tightly sealed with the upper end surface of the extrusion chamber 4. As the extrusion column rotates, it continuously compresses the oxygen flow to open the air outlet slit 3 and enter the water injection observation bottle through the first air supply pipe. During the recovery process of the extrusion chamber 4, the internal air pressure decreases, and the new oxygen refills the extrusion 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 obtain a video stream of bubbles in the water injection observation bottle, send a corresponding recognition model for recognition, and count the bubbles; the recognition model used in this scheme is trained based on an existing neural network model and will not be repeated here.

[0029] This design can control the speed of the micro-drive motor to finely adjust the oxygen flow without using a solenoid valve with micropores. It is low-cost and easy to replace and maintain. The second pressure-limiting valve can moderate the pulsed oxygen flow and deliver it smoothly to the user.

[0030] Optionally, the work status assessment score The acquisition methods include: Get within the specified time period, is the actual amount of bubbles emitted from the water-filled observation bottle, is the actual average speed of the micro drive motor, is the theoretical bubble output corresponding to the actual average speed, The solution adopts a two-way evaluation strategy, which can reduce the large error that may be caused by single-angle evaluation.

[0031] Optionally, the oxygen concentrator includes a compensation unit, which is connected to the micro-drive motor and is used to control the extrusion stroke of the extrusion part on the cylindrical elastic body 2; the compensation unit can be driven by electromagnetic attraction or repulsion, or directly by a worm gear, with the goal of achieving the micro-drive motor moving perpendicular to the axis of the cylindrical elastic body 2.

[0032] When the work status evaluation score When the score is higher than the specified value, the specified value can be configured as 0.1, and the extrusion stroke is adjusted until the working status evaluation score is Less than or equal to the specified score.

[0033] The present application also discloses an oxygen concentrator flow automatic control system, which includes: Configuration module, used to configure the target oxygen flow required by the target personnel at the beginning and target oxygen concentration ; Acquisition module, used to obtain actual oxygen flow in real time and actual oxygen concentration ; Microcontroller for calculating effective oxygen uptake deviation , when the effective oxygen uptake deviates Not less than the specified oxygen uptake , dynamically obtain short-term oxygen configuration flow ; Based on the short-term oxygen configuration flow The actual oxygen flow rate The deviation is used to generate flow control signal through the preset PID control algorithm ; driving a flow regulating actuator to output oxygen according to the flow control signal; During the configuration of the PID control algorithm, the target person adopts the first parameter group during the inhalation phase. , using the second parameter set during the exhalation phase of the target person ,in, , .

[0034] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method for automatic flow control of an oxygen concentrator, characterized in that: The automatic flow control method comprises: Configure the target oxygen flow rate required by the target personnel and target oxygen concentration ; Obtain actual oxygen flow in real time and actual oxygen concentration ; Calculating effective oxygen uptake deviation , when the effective oxygen uptake deviates Not less than the specified oxygen uptake , dynamically obtain short-term oxygen configuration flow ; Based on the short-term oxygen configuration flow The actual oxygen flow rate The deviation is used to generate flow control signal through the preset PID control algorithm ; driving a flow regulating actuator to output oxygen according to the flow control signal; During the configuration of the PID control algorithm, the target person adopts the first parameter group during the inhalation phase. , using the second parameter set during the exhalation phase of the target person ,in, , .

2. The oxygen concentrator flow automatic control method according to claim 1, characterized in that: The PID control algorithm includes: in, , Configure the current oxygen flow rate and output driving the oxygen emission frequency of the flow regulating actuator, Traversal starts from the system To the current moment All time points, Represents every The flow deviation value corresponding to the moment.

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

4. The oxygen concentrator flow automatic control method according to claim 1, characterized in that: The method for identifying the inhalation phase is: performing first-order difference calculation on the flow sensor signal, and determining that inhalation has begun when the difference value exceeds a threshold value three times in a row.

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

6. The oxygen concentrator flow automatic control method according to claim 1, characterized in that: The oxygen concentrator comprises an oxygen concentrating unit, a first pressure-limiting valve (1), an elastic one-way gas outlet core, a first gas supply pipe, a water injection observation bottle, a second gas supply pipe and a second pressure-limiting valve, which are sequentially connected; The elastic one-way air outlet core comprises a cylindrical elastic body (2), an air outlet slit (3) is provided at one end of the cylindrical elastic body (2) close to the air delivery pipe, two opposite seam surfaces of the air outlet slit (3) are tightly pressed against each other and sealed, an air inlet channel is provided at one end of the cylindrical elastic body (2) close to the pressure limiting valve, and an extrusion chamber (4) is provided between the air inlet channel and the air outlet slit (3); A micro drive motor and an extrusion portion fixed to an output end of the micro drive motor are provided on the outside of the cylindrical elastic body (2); the micro drive motor drives the extrusion portion to rotate and intermittently extrudes the extrusion chamber (4).

7. The oxygen concentrator flow automatic control method according to claim 6, characterized in that: The work status evaluation score The acquisition methods include: Get within the specified time period, is the actual amount of bubbles emitted from the water-filled observation bottle, is the actual average speed of the micro drive motor, is the theoretical bubble output corresponding to the actual average speed, is the theoretical average rotation speed corresponding to the actual bubble output.

8. The oxygen concentrator flow automatic control method according to claim 7, characterized in that: The oxygen concentrator comprises a compensation unit, which is connected to the micro drive motor and is used to control the extrusion stroke of the extrusion part on the cylindrical elastic body (2); When the work status evaluation score When the score is higher than the specified value, the extrusion stroke is adjusted until the working state evaluation score is Less than or equal to the specified score.

9. An oxygen concentrator flow automatic control system, running the oxygen concentrator flow automatic control method according to any one of claims 1 to 8, characterized in that: The automatic flow control system comprises: Configuration module, used to configure the target oxygen flow required by the target personnel at the beginning and target oxygen concentration ; Acquisition module, used to obtain actual oxygen flow in real time and actual oxygen concentration ; Microcontroller for calculating effective oxygen uptake deviation , when the effective oxygen uptake deviates Not less than the specified oxygen uptake , dynamically obtain short-term oxygen configuration flow ; Based on the short-term oxygen configuration flow The actual oxygen flow rate The deviation is used to generate flow control signal through the preset PID control algorithm ; driving a flow regulating actuator to output oxygen according to the flow control signal; During the configuration of the PID control algorithm, the target person adopts the first parameter group during the inhalation phase. , using the second parameter set during the exhalation phase of the target person ,in, , .

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