Particulate matter sampler with self-learning and self-adaptive calibration functions

Abstract

The invention provides a particulate matter sampler with a self-learning and self-adaptive calibration function, and relates to the field of particulate matter sampling, the particulate matter sampler comprises a sampling head, a sucking pump, a flowmeter, a gas circuit pipeline, a multi-parameter sensing module, a control terminal and a self-calibration execution unit; the sampling head is communicated with a sucking pump through a gas path pipeline; a flow meter and a multi-parameter sensing module are arranged in the gas path pipeline; the self-calibration execution unit comprises an electric three-way ball valve, a built-in standard critical hole calibration module and a self-cleaning device; three interfaces of the electric three-way ball valve are respectively connected with a gas circuit pipeline between the flowmeter and the sucking pump, an outlet of the standard critical hole calibration module and a blowback gas port of the self-cleaning device; an inlet of the standard critical hole calibration module is connected with a gas path pipeline between the sampling head and the flowmeter; the control terminal comprises an LSTM prediction unit and is electrically connected with the flow meter, the sensor, the air pump and the self-calibration execution unit. The problem of high maintenance cost of the online particulate matter sampler is solved, the maintenance period can be prolonged, and the maintenance cost is reduced.

Description

Technical Field

[0001] The present invention relates to the field of particle sampling, and in particular to a particle sampler with a self-learning and adaptive calibration function. Background Art

[0002] Automatic air quality monitoring stations are generally equipped with online particulate matter samplers, and flow rate is a key parameter that determines the accuracy of particulate matter sampling. In the existing technology, some samplers achieve automatic calibration functions through integrated flow meters. For example, the "An Online Particulate Matter Analyzer Flow Automatic Inspection and Calibration Device" disclosed in the Chinese patent (application number: 201621103247.7, authorization announcement number: CN206095369U) connects the particulate matter analyzer to an external standard flow meter through a connection switch. The control terminal compares the instantaneous flow values ​​of the two. When the difference exceeds the set value (such as 5%), the calibration instruction is triggered to achieve automatic calibration of the flow rate. This solution reduces manual intervention to a certain extent by regularly introducing an external standard flow meter as a benchmark, and is suitable for flow checks in daily operation and maintenance.

[0003] However, the above-mentioned comparative documents have significant defects:

[0004] First, its calibration process only relies on the comparison of real-time volume flow (such as the instantaneous flow value of the standard flow meter and the particle analyzer), and does not involve the impact of temperature, pressure, and humidity on gas volume. This leads to significant errors in the conversion of standard flow in high-altitude, high-temperature and other environments, and cannot meet the high-precision sampling requirements under different environmental conditions. As a standard collection equipment, for environmental particle sampling in different regions, a set of flow calibration parameters for the local environment needs to be specially adapted, which increases the complexity of equipment installation.

[0005] Secondly, its control logic is based on a fixed threshold. For example, calibration is triggered when the flow difference is greater than 5%. However, calibration can only be passively triggered after the flow deviation exceeds the 5% threshold. During this period, low-precision sampling data may have accumulated for several hours to several days, affecting the continuity and reliability of the monitoring results. Moreover, it cannot predict the risk of blockage through abnormal pump electrical parameters, and will not alarm until the flow deviation exceeds the limit. This "post-calibration" may cause the sampling data before calibration to be distorted due to abnormal gas path resistance. This "post-calibration" mode cannot adapt to the gradual degradation of equipment performance, especially in unmanned long-term monitoring scenarios, which can easily lead to the risk of data failure and increase the cost of later data correction. Summary of the Invention

[0006] In response to the above technical problems, the present invention provides a particulate matter sampler with a self-learning and adaptive calibration function, which can extend the maintenance cycle and reduce maintenance costs.

[0007] To achieve the above object, the technical solution adopted by the present invention is:

[0008] The particle sampler with self-learning and adaptive calibration function provided by the present invention comprises a sampling head, an air pump, a flow meter and an air pipeline, and is characterized in that it also comprises a multi-parameter sensing module, a control terminal, a self-calibration execution unit and a storage module; the air outlet of the sampling head is connected to the air inlet of the air pump through the air pipeline; the flow meter is provided on the air pipeline; a first solenoid valve is provided between the flow meter and the air pump; the multi-parameter sensing module comprises a temperature sensor, a pressure sensor, and a humidity sensor; the temperature sensor, the pressure sensor, and the humidity sensor are arranged in the air pipeline; the self-calibration execution unit comprises an electric three-way ball valve, a built-in standard critical hole calibration module and a self-cleaning device; the electric three-way ball valve has a first interface, a second interface, a third interface and a valve body; the valve body can open or close the first interface, the second interface and the third interface Interface; the first interface is connected to the air pipeline; the first interface is connected between the flow meter and the vacuum pump; the standard critical hole calibration module includes a calibration inlet and a calibration outlet; the calibration inlet is connected to the air pipeline; the calibration inlet is connected to the lower side of the flow meter and the upper side of the first solenoid valve; the calibration outlet is connected to the second interface; the self-cleaning device includes a back-blowing air port; the self-cleaning device can blow out gas at the back-blowing air port; the third interface is connected to the back-blowing air port; the control terminal includes an LSTM prediction unit; the LSTM prediction unit can predict the sensor drift trend based on historical calibration data; the control terminal is electrically connected to the flow meter, the temperature sensor, the pressure sensor, the humidity sensor, the vacuum pump, the electric three-way ball valve, the first solenoid valve, the built-in standard critical hole calibration module and the storage module respectively.

[0009] The particulate matter sampler with self-learning adaptive calibration function provided by the present invention preferably comprises the following: the standard critical hole calibration module further comprises a calibration pressure sensor and a plurality of calibration temperature sensors; the calibration pressure sensor is respectively provided at the calibration inlet and the calibration outlet; the calibration temperature sensor is provided at the calibration outlet; the calibration pressure sensor and the calibration temperature sensor are both electrically connected to the control terminal.

[0010] The particulate matter sampler with self-learning and adaptive calibration function provided by the present invention preferably includes a gas storage tank and a second solenoid valve; the gas storage tank is connected to the third interface through the second solenoid valve; and the second solenoid valve is electrically connected to the control terminal.

[0011] The particulate matter sampler with self-learning adaptive calibration function provided by the present invention preferably comprises the following: the standard critical hole calibration module further comprising a constant temperature chamber and a flow limiting orifice; the flow limiting orifice and the calibration temperature sensor are arranged in the constant temperature chamber; the constant temperature chamber is configured to control the temperature of the flow limiting orifice at 20±0.5°C; the flow limiting orifice is arranged between the calibration inlet and the calibration outlet; a standard critical hole with a diameter of 0.5-1.5 mm is provided at the center of the flow limiting orifice.

[0012] The particle sampler with self-learning and adaptive calibration function provided by the present invention is preferably provided with an anti-static coating on the inner wall of the gas pipeline.

[0013] The particulate matter sampler with a self-learning and adaptive calibration function provided by the present invention is preferably provided with a third solenoid valve at the inlet of the air pump; and the third solenoid valve is electrically connected to the control terminal.

[0014] The above technical solution has the following advantages or beneficial effects:

[0015] The present invention provides a particulate matter sampler with a self-learning and adaptive calibration function, which relates to the field of particulate matter sampling, includes a sampling head, an air pump, a flow meter and an air pipeline, and is characterized in that it also includes a multi-parameter sensing module, a control terminal, a self-calibration execution unit and a storage module; the air outlet of the sampling head is connected to the air inlet of the air pump through the air pipeline; the flow meter is provided on the air pipeline; a first solenoid valve is provided between the flow meter and the air pump; the multi-parameter sensing module includes a temperature sensor, a pressure sensor, and a humidity sensor; the temperature sensor, the pressure sensor, and the humidity sensor are arranged in the air pipeline; the self-calibration execution unit includes an electric three-way ball valve, a built-in standard critical hole calibration module and a self-cleaning device; the electric three-way ball valve has a first interface, a second interface, a third interface and a valve body; the valve body can open or close the first interface, the second interface and the third interface; the first interface is connected to the air pipeline; the first interface is connected between the flow meter and the vacuum pump; the standard critical hole calibration module includes a calibration inlet and a calibration outlet; the calibration inlet is connected to the air pipeline; the calibration inlet is connected to the lower side of the flow meter and the upper side of the first solenoid valve; the calibration outlet is connected to the second interface; the self-cleaning device includes a back-blowing air port; the self-cleaning device can blow out gas at the back-blowing air port; the third interface is connected to the back-blowing air port; the control terminal includes an LSTM prediction unit; the LSTM prediction unit can predict the sensor drift trend based on historical calibration data; the control terminal is electrically connected to the flow meter, the temperature sensor, the pressure sensor, the humidity sensor, the vacuum pump, the electric three-way ball valve, the first solenoid valve, the built-in standard critical hole calibration module and the storage module respectively. The particulate matter sampler with self-learning adaptive calibration function provided by the present invention solves the problem of high maintenance cost of online particulate matter samplers in the prior art, can extend the maintenance cycle and reduce maintenance cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention and its features, configurations, and advantages will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings. Like reference numerals indicate like parts throughout the drawings. The drawings are not drawn to scale, emphasis instead being placed on illustrating the subject matter of the present invention.

[0017] Figure 1 This is a schematic diagram of the overall structure of a particulate matter sampler with a self-learning and adaptive calibration function provided in Example 1 of the present invention.

[0018] Figure 2 This is a circuit wireframe connection diagram of a particulate matter sampler with a self-learning and adaptive calibration function provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0019] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of this application can be combined with each other. It should be noted that the terms used in the present invention are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to this application.

[0020] The technical solutions in the embodiments of the present invention are described below in conjunction with the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Therefore, the detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making any creative efforts shall fall within the scope of protection of the present invention.

[0021] Example 1:

[0022] The particle sampler with self-learning and adaptive calibration function provided in embodiment 1 of the present invention is as follows: Figures 1 to 2 As shown, it includes a sampling head 1, an air pump 2, a flow meter 3, an air pipeline 4, a multi-parameter sensing module, a control terminal 6, a self-calibration execution unit 7 and a storage module 8; the air outlet of the sampling head 1 is connected to the air inlet of the air pump 2 through the air pipeline 4; the air pipeline 4 is provided with a flow meter 3; a first solenoid valve 31 is provided between the flow meter 3 and the air pump 2; the multi-parameter sensing module includes a temperature sensor 51, a pressure sensor 52, and a humidity sensor 53; the temperature sensor 51, the pressure sensor 52, and the humidity sensor 53 are arranged in the air pipeline 4; the self-calibration execution unit 7 includes an electric three-way ball valve 71, a built-in standard critical hole calibration module and a self-cleaning device 73; the electric three-way ball valve 71 has a first interface 711, a second interface 712, a third interface 713 and a valve body; the valve body can open or close the first interface 711, the second interface 712 and the third interface 713; The first interface 711 is connected to the air path pipeline 4; the first interface 711 is connected between the flow meter 3 and the first solenoid valve 31; the standard critical hole calibration module includes a calibration inlet 721 and a calibration outlet 722; the calibration inlet 721 is connected to the air path pipeline 4; the calibration inlet 721 is connected between the sampling head 1 and the flow meter 3; the calibration outlet 722 is connected to the second interface 712; the self-cleaning device 73 includes a back-blowing air port; the self-cleaning device 73 can blow out gas at the back-blowing air port; the third interface 713 is connected to the back-blowing air port; the control terminal 6 includes an LSTM prediction unit; the LSTM prediction unit can predict the sensor drift trend based on historical calibration data; the control terminal 6 is electrically connected to the flow meter 3, the temperature sensor 51, the pressure sensor 52, the humidity sensor 53, the vacuum pump 2, the electric three-way ball valve 71, the first solenoid valve 31, the built-in standard critical hole calibration module and the storage module 8 respectively.

[0023] The particulate matter sampler with self-learning adaptive calibration function provided in Example 1 of the present invention has four modes when in use: normal sampling, automatic flow calibration, automatic cleaning, and predictive maintenance:

[0024] The purpose of the normal sampling mode is to collect environmental particulate matter and measure the flow rate through the flow meter 3 at all times (the device 01 for realizing automatic membrane replacement is set on the air path 4 above the flow meter 3 and below the sampling head 1. The device for realizing automatic membrane replacement is a prior art and will not be described in detail here). According to the measurement data of the flow meter 3, the air pump 2 is adjusted to ensure the speed at which air enters the sampling head 1. In this mode, under the control of the control terminal 6, the first solenoid valve 31 is in the open state (allowing gas to pass through), and the first interface 711, the second interface 712, and the third interface 713 are all in Closed state; the specific work flow is that the control terminal 6 starts the vacuum pump 2, and the ambient air enters the gas pipeline 4 through the sampling head 1; the gas flows through the flow meter 3, the flow meter measures the real-time flow and transmits the data to the control terminal 6; the temperature sensor 51, the pressure sensor 52, and the humidity sensor 53 in the multi-parameter sensing module synchronously monitor the gas parameters for correcting the flow data (such as temperature and pressure compensation, Q measured = Q measured actual * (P measured actual / P standard condition) * (T standard condition / T measured actual)); the processed data is stored in the storage module 8 as a historical sampling record.

[0025] The purpose of automatic flow calibration is to calibrate the accuracy of the flow meter 3 using the standard critical hole calibration module; in this mode, the first solenoid valve 31 is in a closed state, the first interface 711 and the second interface 712 are open; the third interface 713 is closed; the specific working process is that the vacuum pump 2 is started, and the gas enters the standard critical hole calibration module from the calibration inlet 721 through the flow meter 3 (the standard critical hole calibration module can provide a standard flow, and the specific structure of this embodiment is reflected below); the control terminal 6 obtains the flow data obtained by the standard critical hole calibration module, and then the control terminal 6 compares the flow data obtained by the standard critical hole calibration module with the flow meter 3 data, calculates the error and generates a calibration coefficient, and the control terminal 6 adjusts the vacuum pump 2 according to the standard critical hole calibration module data; after automatic flow calibration, adjustments are made based on the calibration coefficient of the flow meter 3 data, and the vacuum pump 2 is controlled according to the adjustment data.

[0026] The purpose of self-cleaning is to remove particulate dust on the surface of the sampling head 1 and the flow meter 3; in this mode, the first solenoid valve 31 is in a closed state, the first interface 711 and the third interface 713 are open; the second interface 712 is closed; the specific working process is that the self-cleaning device 73 injects high-pressure gas (such as compressed air or nitrogen) into the third interface 713 through the back-blowing air port; the back-blowing air flows through the first interface 711 into the air path pipe 4, flows in the reverse direction through the flow meter 3 and the sampling head 1, and removes the accumulated dust; the accumulated dust is discharged from the sampling head 1 with the air flow, and the cleaning is completed.

[0027] The purpose of the intelligent prediction and maintenance mode is to predict sensor performance based on historical data and optimize the calibration cycle; during automatic flow calibration, external air will enter from the sampling head 1 and enter the standard critical hole calibration module from the calibration inlet 721 through the air pipe 4, causing contamination of the standard critical hole calibration module. If automatic calibration is used frequently, the accuracy of the standard critical hole module may decrease due to contamination; if only relying on a fixed threshold (such as a difference greater than 5%) to passively trigger calibration, low-precision data may accumulate, and low-precision sampling data may have accumulated for several hours to several days during this period, affecting the continuity and reliability of the monitoring results. The LSTM prediction unit of the control terminal 6 of this embodiment (the LSTM prediction unit is a long short-term memory network prediction unit, which can analyze data and make predictions. Since it is a prior art, it will not be described in detail here) continuously analyzes the historical calibration parameters, environmental parameters (temperature, humidity, etc.) and sensor drift trends in the storage module 8, predicts possible measurement errors in the future, outputs a corrected signal based on historical calibration data and flow meter measurement values ​​to the vacuum pump 2, and plans the calibration time point (such as when the prediction error is close to the allowable range, the calibration mode is automatically triggered); thereby reducing the frequency of automatic flow calibration, extending the overall maintenance cycle of the equipment, reducing maintenance costs, and better reducing flow deviation while reducing frequency.

[0028] The particle sampler with a self-learning and adaptive calibration function provided in this embodiment solves the problem of high maintenance cost of online particle samplers in the prior art, thereby extending the maintenance cycle and reducing maintenance costs.

[0029] As a preferred embodiment, in this embodiment, the standard critical orifice calibration module further includes a calibration pressure sensor 723 and a calibration temperature sensor 724. Calibration pressure sensors 723 are provided at the calibration inlet 721 and calibration outlet 722; calibration temperature sensor 724 is provided at the calibration outlet 722. Both calibration pressure sensor 723 and calibration temperature sensor 724 are electrically connected to the control terminal 6. Calibration pressure sensor 723 and calibration temperature sensor 724 are provided within the self-calibration execution unit 7 to directly measure the real-time temperature and pressure at the critical orifice inlet and outlet, ensuring that the calculated standard flow value (which serves as the calibration reference) is highly accurate.

[0030] As a preferred solution, in this embodiment, the self-cleaning device 73 further includes a gas tank 731 and a second solenoid valve 732; the gas tank 731 is connected to the third interface 713 via the second solenoid valve 732; and the second solenoid valve 732 is electrically connected to the control terminal 6. The control terminal 6 can output the clean gas in the gas tank 731 by controlling the opening and closing of the second solenoid valve 732; the gas tank 731 can pre-store clean gas (preferably dry compressed air in this embodiment) to ensure that a pulsed airflow with a certain pressure and flow rate can be quickly released during self-cleaning to powerfully purge key parts such as the gas pipeline, sampling head, and flow meter. If it directly relies on an external gas source, the backflushing force may be insufficient due to pressure fluctuations, or impurities in the external gas source may contaminate the sampler.

[0031] As a preferred embodiment, in this embodiment, the standard critical orifice calibration module further includes a constant temperature chamber 725 and a flow restriction orifice 726. The constant temperature chamber 725 controls the temperature of the flow restriction orifice 726 at 20±0.5°C. The flow restriction orifice 726 and a calibration temperature sensor 723 are disposed within the constant temperature chamber 725. The flow restriction orifice 726 is disposed between the calibration inlet 721 and the calibration outlet 722. A standard critical orifice with a diameter of 0.5-1.5 mm is provided in the center of the flow restriction orifice 726. When the system enters calibration mode, the electric three-way ball valve 71 switches the gas path, diverting the main gas path gas to the standard critical orifice calibration module: the gas enters the constant temperature chamber from the calibration inlet 721, flows through the critical orifice after flow restriction, and exits the calibration outlet 722. The calibration pressure sensor 723 monitors the upstream pressure P1 in real time and, based on the constant temperature chamber temperature of 20°C, calculates the standard flow rate Qstandard using a formula. The control terminal 6 compares the real-time measurement value Qmeasured of the main gas path flowmeter 3 with Qstandard, calculates the deviation, and performs calibration parameter correction.

[0032] Calculation of Q mark: The flow formula of gas flowing through the critical hole is: Q mark = C*A*P1*√(M / RT1).

[0033]

[0034] C is the flow coefficient (related to the orifice shape, preset in the control terminal 6),

[0035] A is the critical hole cross-sectional area (preset in the control terminal 6),

[0036] P1 is the upstream absolute pressure (measured by calibrated pressure sensor 723),

[0037] M is the molar mass of the gas,

[0038] R is the gas constant,

[0039] T1 is the thermodynamic temperature of the upstream gas. Since the temperature T1 directly affects the gas density ρ = RT / PM, if the temperature fluctuates, even if the pressure is constant, the flow rate will still change. For example, for every 1°C change in temperature, the air density changes by approximately 0.35%, resulting in a synchronous fluctuation in the flow rate error. Therefore, in this embodiment, a constant temperature chamber is set up to control the temperature of the flow-limiting orifice plate at 20 ± 0.5°C to ensure constant density and stable flow coefficient; P1 is the upstream absolute pressure, and the value of P1 is different at different altitudes; the critical hole diameter is set to 0.5 - 1.5 mm (preferably 1 mm in this embodiment). The reason is that a smaller hole diameter causes the gas to flow through at a faster speed, making it easier to satisfy that the ratio of the downstream pressure P2 (a calibration pressure sensor is also set on the lower side of the flow-limiting orifice plate 726 to measure the downstream pressure P2) to the upstream pressure P1 is less than or equal to 0.528 (critical flow state). The specific operation is to adjust the pump speed according to the ratio of P1 to P2. In the state of less than or equal to 0.528, the dynamic reference flow rate Q standard under the current environment is obtained. When adjusting the pump speed of the air extraction pump 2 as described above, the difference and relative error between Q measured and Q standard can be calculated: difference / Q standard, to clarify the magnitude of the flow deviation and provide a basis for pump power adjustment; in the calibration mode, adjust the air extraction pump power. If Q measured > Q standard, reduce the pump power; if Q measured < Q standard, increase the pump power. Based on the pump characteristic curve (the "rotation speed - flow rate" mapping table calibrated at the factory), convert the Q difference into the pump rotation speed adjustment.

[0040] The Q standard of the critical hole is the true flow rate, and the Q measured displayed by the flow meter is a measured value with an error. According to the values of Q standard and Q measured, correction parameters are formed (for example, linear correction coefficient: K = Q standard / Q measured; offset correction: ΔQ = Q standard - Q measured). After calibration, adjust the value of Q measured through the correction coefficient to form the Q measured correction; specifically, within a calibration period, multiple calibrations can be performed until the error between Q measured and Q standard is less than ±1%. According to the deviation between Q measured and Q standard under multiple calibrations, select an appropriate correction method, and then in the subsequent sampling mode, follow this correction method to form the Q measured correction and use the power of the air extraction pump 2 that forms the Q measured correction.

[0041] In this embodiment, an anti-static coating is provided on the inner wall of the gas pipeline 4. During the gas flow process, the inner wall of the gas pipeline 4 is prone to generating static electricity when rubbing against gas molecules and dust particles. The charged surface will adsorb dust, aerosol and other particles in the air; the anti-static coating can prevent particles from adsorbing to the inner wall of the gas pipeline 4 and avoid measurement deviation.

[0042] In this embodiment, a third solenoid valve 21 is provided at the inlet of the air extraction pump 2; the third solenoid valve 21 is electrically connected to the control terminal 6. During the self-cleaning period, the control terminal 6 closes the air extraction pump 2, and the third solenoid valve 21 closes to prevent the backflush air from flowing through the first interface 711 into the gas pipeline 4 and directly entering the air extraction pump 2, causing damage to the air extraction pump 2.

[0043] In summary, the present invention provides a particulate matter sampler with a self-learning and adaptive calibration function, which relates to the field of particulate matter sampling, including a sampling head, an air pump, a flow meter and an air pipeline, and is characterized in that it also includes a multi-parameter sensing module, a control terminal, a self-calibration execution unit and a storage module; the air outlet of the sampling head is connected to the air inlet of the air pump through the air pipeline; the flow meter is provided on the air pipeline; a first solenoid valve is provided between the flow meter and the air pump; the multi-parameter sensing module includes a temperature sensor, a pressure sensor, and a humidity sensor; the temperature sensor, the pressure sensor, and the humidity sensor are arranged in the air pipeline; the self-calibration execution unit includes an electric three-way ball valve, a built-in standard critical hole calibration module and a self-cleaning device; the electric three-way ball valve has a first interface, a second interface, a third interface and a valve body; the valve body can open or close the first interface, the second The interface is connected to the third interface; the first interface is connected to the air pipeline; the first interface is connected between the flow meter and the air pump; the standard critical hole calibration module includes a calibration inlet and a calibration outlet; the calibration inlet is connected to the air pipeline; the calibration inlet is connected to the lower side of the flow meter and the upper side of the first solenoid valve; the calibration outlet is connected to the second interface; the self-cleaning device includes a back-blowing air port; the self-cleaning device can blow out gas at the back-blowing air port; the third interface is connected to the back-blowing air port; the control terminal includes an LSTM prediction unit; the LSTM prediction unit can predict the sensor drift trend based on historical calibration data; the control terminal is electrically connected to the flow meter, the temperature sensor, the pressure sensor, the humidity sensor, the air pump, the electric three-way ball valve, the first solenoid valve, the built-in standard critical hole calibration module and the storage module respectively. The particulate sampler with self-learning adaptive calibration function provided by the present invention solves the problem of high maintenance cost of online particulate samplers in the prior art, can extend the maintenance cycle and reduce maintenance cost.

[0044] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformation made by using the contents of the present invention description and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A particle sampler with self-learning and adaptive calibration function, comprising a sampling head, an air pump, a flow meter and an air pipeline, characterized in that: It also includes a multi-parameter sensing module, a control terminal, a self-calibration execution unit and a storage module; The air outlet of the sampling head is connected to the air inlet of the air pump through the air pipeline; the flow meter is provided on the air pipeline; a first solenoid valve is provided between the flow meter and the air pump; The multi-parameter sensing module includes a temperature sensor, a pressure sensor, and a humidity sensor; the temperature sensor, the pressure sensor, and the humidity sensor are arranged in the gas pipeline; The self-calibration execution unit includes an electric three-way ball valve, a built-in standard critical hole calibration module and a self-cleaning device; The electric three-way ball valve has a first interface, a second interface, a third interface and a valve body; The valve body can open or close the first interface, the second interface and the third interface; The first interface is connected to the air pipeline; the first interface is connected between the flow meter and the air pump; The standard critical orifice calibration module includes a calibration inlet and a calibration outlet; the calibration inlet is connected to the gas pipeline; the calibration inlet is connected to the lower side of the flow meter and the upper side of the first solenoid valve; the calibration outlet is connected to the second interface; The self-cleaning device includes a back-blowing port; the self-cleaning device can blow out gas at the back-blowing port; the third interface is connected to the back-blowing port; The control terminal includes an LSTM prediction unit; the LSTM prediction unit can predict the sensor drift trend based on historical calibration data; The control terminal is electrically connected to the flow meter, the temperature sensor, the pressure sensor, the humidity sensor, the air pump, the electric three-way ball valve, the first solenoid valve, the built-in standard critical hole calibration module and the storage module respectively.

2. The particle sampler with self-learning and adaptive calibration function according to claim 1, characterized in that: The standard critical hole calibration module also includes a calibration pressure sensor and a plurality of calibration temperature sensors; The calibration inlet and the calibration outlet are respectively provided with the calibration pressure sensor; The calibration temperature sensor is provided at the calibration outlet; The calibration pressure sensor and the calibration temperature sensor are both electrically connected to the control terminal.

3. The particle sampler with self-learning and adaptive calibration function according to claim 2, characterized in that: The self-cleaning device also includes an air storage tank and a second solenoid valve; The gas storage tank is connected to the third interface through the second solenoid valve; The second solenoid valve is electrically connected to the control terminal.

4. The particle sampler with self-learning and adaptive calibration function according to claim 2, characterized in that: The standard critical orifice calibration module further includes a constant temperature chamber and a flow limiting orifice plate; the constant temperature chamber controls the temperature of the flow limiting orifice plate at 20±0.5°C; The flow limiting orifice and the calibration temperature sensor are arranged in the constant temperature chamber; The flow limiting orifice is arranged between the calibration inlet and the calibration outlet; a standard critical hole with a diameter of 0.5-1.5 mm is opened at the center of the flow limiting orifice.

5. The particle sampler with self-learning and adaptive calibration function according to claim 1, characterized in that: The inner wall of the gas pipeline is provided with an antistatic coating.

6. The particle sampler with self-learning and adaptive calibration function according to claim 1, characterized in that: The inlet of the air pump is provided with a third solenoid valve; the third solenoid valve is electrically connected to the control terminal.

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