Leak Rate Measuring Equipment and System Based on Gas Mass Flow Control Technology

Abstract

The present invention relates to a leak rate measurement device and system based on gas mass flow control technology. The detected first pressure value and the second pressure value pre-input by the user are input into the PID control component, and the PID control component outputs a PID flow value. Furthermore, a target gas mass flow controller with a range matching the PID flow value can be determined, and the PID control component then dynamically adjusts the opening degree of the target gas mass flow controller according to the PID flow value. When the minimum stable time is reached, the human-computer interaction component can output the PID flow value at this time as the leak rate of the measured system. By adopting the technical solution of the present invention, it is not necessary to evacuate, a gas mass flow controller with a range matching the pressure of the measured system is selected, and dynamic adjustment is performed based on the PID control component, which can quickly detect the leak rate of a flexible material system or a low-pressure resistance system, fully meeting the timeliness requirements of mass production.

Description

Technical Field

[0001] The present invention relates to the technical field of equipment detection, and particularly relates to a leak rate measurement device and system based on gas mass flow control technology. Background Art

[0002] There are two traditional methods for leak detection in a closed system: positive pressure leak detection and negative pressure leak detection. The negative pressure leak detection method requires evacuating the entire system to be tested to a preset vacuum level, and then spraying a small amount of high-purity helium gas near the suspected leak point. The leak rate is detected by a helium mass spectrometer leak detector. However, this method requires evacuation and is not suitable for leak detection of flexible material systems. The positive pressure leak detection method requires increasing the pressure of the system to be tested to above 0.5 MPa and connecting an external pressure gauge. After stabilizing for several hours, the pressure gauge reading is taken again, and the leak rate of the closed system is theoretically calculated based on the pressure drop value and time. However, this method has a long detection time and cannot meet the timeliness requirements during mass production. Some materials to be tested have low pressure resistance and cannot use this positive pressure detection method.

[0003] Therefore, how to provide a rapid leak rate detection device suitable for flexible material systems or systems with low pressure resistance is a technical problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a leak rate measurement device and system based on gas mass flow control technology to overcome the problem that the leak rate of flexible material systems or systems with low pressure resistance cannot be detected quickly at present.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions:

[0006] A leak rate measurement device based on gas mass flow control technology includes a cabinet shell, a pressure monitoring component, and a PID control component, a human-machine interaction component, and a plurality of gas mass flow controllers with increasing ranges respectively arranged inside the cabinet shell;

[0007] The inlet end of the gas mass flow controller is used to be connected to a gas source through a first pipeline, the outlet end of the gas mass flow controller is used to be connected to the system to be tested through a second pipeline, and the gas mass flow controller is used to control the inflation flow rate of the system to be tested;

[0008] The pressure monitoring component is arranged at the system to be tested, and the pressure monitoring component is used to monitor the first pressure value inside the system to be tested;

[0009] The PID control component is electrically connected to the pressure monitoring component and the gas mass flow controller respectively;

[0010] The PID control component is used to perform PID control based on the first pressure value and the second pressure value pre-input by the tester through the human-machine interaction component, and output a PID flow value;

[0011] The PID control component is also used to determine a target gas mass flow controller whose range matches the PID flow value, and dynamically adjust the opening degree of the target gas mass flow controller according to the PID flow value until a preset minimum stable time is reached;

[0012] The human-machine interaction component is used to output the PID flow value corresponding to the minimum stable time as the leak rate of the system under test.

[0013] Further, for the leak rate measuring device based on the gas mass flow control technology described above, a stop valve is provided between each gas mass flow controller and the system under test;

[0014] The stop valve is electrically connected to the PID control component;

[0015] The stop valve is used to cut off the gas path of the corresponding gas mass flow controller, avoiding micro-leakage and resulting errors when the gas mass flow controller is in the cut-off state.

[0016] Further, for the leak rate measuring device based on the gas mass flow control technology described above, a high-pressure manual stop valve is provided at the air outlet of the gas source, and the cut-off control knob of the high-pressure manual stop valve is provided on the cabinet shell.

[0017] Further, for the leak rate measuring device based on the gas mass flow control technology described above, a pressure reducing valve is provided at the inlet of the gas mass flow controller;

[0018] The pressure reducing valve is used to reduce the pressure of the gas output by the gas source.

[0019] Further, for the leak rate measuring device based on the gas mass flow control technology described above, the human-machine interaction component is a touch screen;

[0020] The touch screen is embedded on one side of the cabinet shell.

[0021] Further, for the leak rate measuring device based on the gas mass flow control technology described above, the pressure monitoring component and the PID control component interact through digital signals.

[0022] Further, for the leak rate measuring device based on the gas mass flow control technology described above, a one-way valve is provided on the first pipeline and / or the second pipeline.

[0023] Further, for the leak rate measurement device based on the gas mass flow control technology described above, the pressure monitoring component is a high-precision pressure transmitter.

[0024] Further, the leak rate measurement device based on the gas mass flow control technology described above further includes a reminder component;

[0025] The reminder component is connected to the PID control component;

[0026] The PID control component is used to control the reminder component to issue a non-conformance reminder if the leak rate is greater than a preset standard leak rate.

[0027] The present invention also provides a leak rate measurement system based on the gas mass flow control technology, including a gas source and the leak rate measurement device based on the gas mass flow control technology described in any one of the above;

[0028] The gas source is connected to the leak rate measurement device based on the gas mass flow control technology.

[0029] For the leak rate measurement device and system based on the gas mass flow control technology of the present invention, gas mass flow controllers with several ranges are provided. A pressure monitoring component is arranged on the system to be measured to detect the air pressure in the system to be measured at any time. The detected first pressure value and the second pressure value pre-input by the user are input into the PID control component, and the PID control component outputs a PID flow value. Furthermore, a target gas mass flow controller with a range matching the PID flow value can be determined, and the PID control component then dynamically adjusts the opening of the target gas mass flow controller according to the PID flow value. When the minimum stable time is reached, the human-computer interaction component can output the PID flow value at this time as the leak rate of the system to be measured. By adopting the technical solution of the present invention, it is not necessary to evacuate, a gas mass flow controller with a range matching the pressure of the system to be measured is selected, and dynamic adjustment is performed based on the PID control component, so that the leak rate of a flexible material system or a system with low pressure resistance can be quickly detected, fully meeting the timeliness of mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0031] Figure 1 It is a schematic structural diagram provided by an embodiment of the leak rate measurement device based on the gas mass flow control technology of the present invention;

[0032] Figure 2 is Figure 1 a schematic structural diagram of area A in

[0033] Figure 3 a schematic circuit diagram provided by an embodiment of a leak rate measuring device based on gas mass flow control technology of the present invention;

[0034] Figure 4 a schematic structural diagram provided by an embodiment of a leak rate measuring system based on gas mass flow control technology of the present invention. Specific embodiments

[0035] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be described in detail below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the scope protected by the present invention.

[0036] Figure 1 a schematic structural diagram provided by an embodiment of a leak rate measuring device based on gas mass flow control technology of the present invention, Figure 2 is Figure 1 a schematic structural diagram of area A in Figure 3 a schematic circuit diagram provided by an embodiment of a leak rate measuring device based on gas mass flow control technology of the present invention. Please refer to Figure 1 , Figure 2 and Figure 3 , the leak rate measuring device based on gas mass flow control technology of this embodiment includes a cabinet housing 100, a pressure monitoring component 101, and a PID control component 102, a human-machine interaction component 103, and a number of gas mass flow controllers 104 with increasing ranges respectively arranged in the cabinet housing 100.

[0037] Generally, due to the different materials and functions of the measured system, its leak rate range is also different. Therefore, the leak rate ranges of measured systems with different materials and functions may vary greatly. Generally, the controllable range ratio of the gas mass flow controller 104 is 1:50. In order to achieve the best precision control range and adapt to measured systems with different materials and functions, a number of gas mass flow controllers 104 with increasing ranges can be set. For example, 3 gas mass flow controllers 104 can be set, with the largest one having a full scale of 30 liters per minute, the middle one having 10 liters per minute, and the last one having 3 liters per minute. Then, this combination of gas mass flow controllers 104 can measure a range of about 30 liters per minute to 1 liter per minute. If the measured system requires more precise leak rate data, gas mass flow controllers 104 with smaller ranges can also be set, generally about 1 - 5 can be set, and this embodiment does not make a limitation.

[0038] The intake end of the gas mass flow controller 104 is used to be connected to a gas source through the first pipeline 105, and the outlet end of the gas mass flow controller 104 is used to be connected to the system under test through the second pipeline 106. The gas mass flow controller 104 is used to control the inflation flow rate of the system under test.

[0039] The pressure monitoring component 101 is arranged at the system under test. In this embodiment, two placement points of the pressure monitoring component 101 are provided. One is at the end of the outlet of the second pipeline 106, and the other is to arrange the pressure monitoring component 101 on the interface if there is a suitable interface in the cavity of the system under test. The pressure monitoring component 101 is used to monitor the first pressure value in the system under test.

[0040] The PID control component 102 is electrically connected to the pressure monitoring component 101 and the gas mass flow controller 104 respectively.

[0041] In a specific implementation process, the user can select the gas mass flow controller 104 participating in this test from all the gas mass flow controllers 104 according to the volume of the system under test. For example, if the volume of the system under test is 40L, and the ranges of the gas mass flow controllers 104 are 1 liter per minute, 3 liters per minute, 10 liters per minute, and 30 liters per minute respectively, then the user can select all these 4 gas mass flow controllers 104 for batch detection. If the volume of the system under test is 10L, then the user can select the gas mass flow controllers 104 with ranges of 1 liter per minute, 3 liters per minute, and 10 liters per minute.

[0042] In addition, the user can also set a program. After inputting the volume of the system under test, the PID control component 102 automatically selects the gas mass flow controller 104.

[0043] The PID control component 102 is used to perform PID control according to the first pressure value and the second pressure value pre-input by the tester through the human-machine interaction component 103, and output a PID flow value. Specifically, during the PID control process, when the test starts, the first pressure value is lower than the input second pressure value, and the PID flow value output by the PID control component 102 is larger, quickly filling the system under test to above atmospheric pressure. When the first pressure value is closer to the input second pressure value, the PID flow value output by the PID control component 102 is smaller. Moreover, since the gas has a certain compressibility, there may be a situation where the first pressure value is greater than the second pressure value, and at this time, the PID flow value is quickly reduced.

[0044] PID control is widely used in engineering control. The basic implementation formula of PID is as follows:

[0045] u(t) = Kp×e(t) + Ki∑e(t) + Kd[e(t) – e(t - 1)] + u0

[0046] In this embodiment, u0 is the second pressure value, e(t) is the deviation between the first pressure value and the second pressure value, and u(t) is the output PID flow value. Kp, Ki, and Kd are parameters in the PID control process. During actual debugging, Kp, Ki, and Kd need to be repeatedly debugged to achieve the best effect, which is not limited in this embodiment.

[0047] The PID control component 102 is also used to select a target gas mass flow controller whose range matches the PID flow value, that is, the PID flow value should be within the range of the gas mass flow controller 104. And to improve speed and accuracy, in addition to meeting the condition that the PID flow value should be within the range of the gas mass flow, the range of the target gas mass flow controller should be closest to the PID flow value.

[0048] For example, during a detection process, gas mass flow controllers 104 with ranges of 1 liter per minute, 3 liters per minute, and 10 liters per minute are selected. When the test starts and the PID flow value is 10 liters per minute, then a target gas mass flow controller with a range of 10 liters per minute can be selected to work. As the first pressure value gradually increases, under the control of the PID control component 102, the PID flow value gradually decreases, and the opening of the target gas mass flow controller is reduced according to the PID flow value; when the PID flow value decreases to 3 liters per minute, a target gas mass flow controller with a range of 3 liters per minute can be selected to work, and the opening of the target gas mass flow controller is reduced according to the PID flow value; as the first pressure value gradually increases and the PID flow value further decreases, when it decreases to 1 liter per minute, a target gas mass flow controller with a range of 1 liter per minute can be selected to work, and the opening of the target gas mass flow controller is reduced according to the PID flow value.

[0049] When the first pressure value increases to the second pressure value and can remain stable within the preset time, it can be considered that the preset minimum stable time is reached, and the corresponding PID flow value at this time is the leak rate of the measured system.

[0050] In this embodiment, the human - machine interaction component 103 is used to output the leak rate of the measured system.

[0051] Furthermore, in the leak rate measurement device based on gas mass flow control technology of this embodiment, a stop valve 107 is provided between each gas mass flow controller 104 and the measured system, and the stop valve 107 is electrically connected to the PID control component 102.

[0052] When the gas mass flow controller 104 corresponding to the stop valve 107 starts to work as the target gas mass flow controller, the PID control component 102 can control the opening of the stop valve 107, and the other stop valves 107 are in the closed state, so as to avoid micro-leakage of the gas mass flow controller 104 and cause errors. Among them, the stop valve 107 is preferably an electromagnetic stop valve.

[0053] Further, a high-pressure manual stop valve 108 is provided at the air outlet of the gas source, and the stop control knob of the high-pressure manual stop valve 108 is arranged on the cabinet shell 100. The tester can perform overall control on the on-off of the gas source by controlling the high-pressure manual stop valve 108.

[0054] Further, a pressure reducing valve 109 is provided at the air inlet of the gas mass flow controller 104. The outlet pressure of the gas source is relatively high, generally about 15 MPa, while the gas mass flow controller 104 generally works under a pressure of about 0.3 MPa. Therefore, a pressure reducing valve 109 is provided at the air inlet of the gas mass flow controller 104 to reduce the gas pressure to the available pressure of the gas mass flow controller 104.

[0055] Further, the human-computer interaction component 103 includes a touch screen and a microprocessor, and the touch screen is embedded on one side of the cabinet shell 100. Since the gas has compressible properties, the entire PID control process is not a symmetric process of increase and decrease, and there may be multiple oscillation adjustments. Therefore, with the increase in the volume of the measured system and the different stable pressures in this embodiment, the detection time of the detection device in this embodiment may last for several minutes. The microprocessor in this embodiment is provided with functions such as automatic data recording, one-key start, and automatic result export, so as to achieve unattended operation during this period.

[0056] Further, in this embodiment, the pressure monitoring component 101 and the PID control component 102 preferably interact through digital signals, such as RS485 communication, CAN communication, IIC communication, SPI communication, PROFIBUS communication, or DEVICENET communication, etc. The analog signal form is not adopted in this embodiment because the small fluctuations of the analog signal may cause the stabilization time of the entire leak detection system to be too slow, so that the leak rate of the system cannot be read.

[0057] Further, check valves are provided on the first pipeline 105 and / or the second pipeline 106 of this embodiment to prevent the reverse transmission of gas from damaging the equipment and affecting the experimental results.

[0058] Further, the pressure monitoring component 101 in this embodiment is a high-precision pressure transmitter, and the accuracy class requirement reaches 0.1% F.S. Moreover, the communication speed of the pressure monitoring component 101 needs to reach at least 200 ms / byte. The reason is that for the measured system, there is an instantaneous increase in the internal pressure from low to high. Therefore, it is necessary to collect this pressure signal at high speed. If there is a delay in the system, it may cause a lag in control, resulting in excessive overshoot of the pressure in the sealed cavity. In the lightest case, the control speed is reduced, and in the worst case, the measured system is damaged.

[0059] Further, the leak rate measurement device based on the gas mass flow control technology in this embodiment further includes a reminder component, and the reminder component is connected to the PID control component 102. The PID control component 102 is used to control the reminder component to issue an unqualified reminder if the leak rate is greater than the preset standard leak rate. The reminder component can select devices such as a flash lamp or a buzzer, and a voice output device can also be selected. This embodiment does not make a limitation.

[0060] It should be noted that the leak rate measurement device based on the gas mass flow control technology in this embodiment is mainly used for slightly positive pressure detection. The input second voltage value generally does not exceed 0.05 MPa, and it is mainly used for leak rate detection of flexible material systems or low-pressure resistance systems.

[0061] Here, a 30-liter volume sealed chemical protection suit is taken as an example for further illustration. This embodiment requires that the sealed chemical protection suit is qualified within 20 milliliters per minute under a slightly positive pressure of 0.04 MPa, that is, the input second pressure value is 0.04 MPa.

[0062] The pressure of the gas source entering the leak rate measurement device is the cylinder pressure, about 15 MPa, and the pressure reducing valve 109 is used to reduce the pressure to about 0.3 MPa available for the gas mass flow controller 104.

[0063] Among them, the maximum range of one of the gas mass flow controllers 104 is 30 liters per minute for the full scale, one is 10 liters per minute, and the last one is 3 liters per minute. In addition, the gas mass flow controller 104 selects products with a control speed within 1 second to avoid the entire system being stuck in continuous PID adjustment due to slow response time.

[0064] The stop valve 107 behind each gas mass flow controller 104 is used to completely cut off the gas path to avoid errors caused by micro-leaks. Here, the stop valve 107 can use a stop valve with a pressure resistance of 1 MPa, and high-pressure products are not used to save costs. Since there is an interface inside the sealed chemical protection suit, in this embodiment, the pressure monitoring component 101 is arranged on the interface.

[0065] The interface of the human-computer interaction component 103 uses a 15-inch touch screen. The PID control component 102 is designed with an embedded processor with a 32-bit or higher kernel. It is preferably designed with a chip with built-in AD acquisition and DA output (such as the ADUC7 series single-chip microcomputer), or configured with mature products such as PLC + communication module + AD / DA module. After overall system calculation, it is ultimately necessary to ensure that the pressure acquisition interval is at most 200 ms, adjust the gas flow within 100 ms after reading the pressure signal, and stabilize the flow within 1 s.

[0066] After the system hardware is connected, the PID control function is started. At the beginning, the first pressure value is much lower than the second pressure value (0.04 MPa). The PID control component 102 will increase the PID flow value. Since the volume of the airtight chemical protection suit cavity is about 30 liters, a target gas mass flow controller with a full scale of 30 liters per minute is first selected to work. Therefore, at the beginning, the PID flow value will gradually increase, and the airtight chemical protection suit will be filled above atmospheric pressure stably within 1 minute. At this time, the PID flow value will increase slowly. The closer the first pressure value is to the second pressure value, the lower the PID flow value. When it is lower than 10 liters per minute, it automatically switches through the stop valve 107 to work with a target gas mass flow controller of 10 liters per minute. When the PID flow value is lower than 3 liters per minute, it automatically switches through the stop valve 107 to work with a target gas mass flow controller of 3 liters per minute. Due to the compressible nature of the gas, there will be a certain amount of overshoot in the system. When it exceeds 0.04 Mpa, the PID flow value is quickly reduced. The PID parameters of the system are repeatedly debugged in this process to finally reach the minimum stable time. The stable PID flow value at this time is the leakage rate of the chemical protection suit at 0.04 MPa.

[0067] This process can be divided into three stages, and different PID parameters are used in each stage. When the flow rate is large in the first stage, only the Kp proportional parameter needs to be set to avoid system delay. In the second and third stages, the Kp proportional parameter and the Ki integral parameter need to be set, and in actual debugging, repeated debugging is carried out to achieve the best effect. The Kd derivative parameter sometimes does not need to be adjusted or is adjusted slightly. The values of these parameters are determined according to the size of different airtight cavities.

[0068] The leak rate measurement device based on the gas mass flow control technology in this embodiment is provided with gas mass flow controllers 104 of several ranges. A pressure monitoring component 101 is set on the system to be measured to detect the air pressure in the system to be measured at any time. The detected first pressure value and the second pressure value pre-input by the user are input into the PID control component 102, and the PID control component 102 outputs a PID flow value. Furthermore, the target gas mass flow controller with a range matching the PID flow value can be determined, and the PID control component 102 can then dynamically adjust the opening of the target gas mass flow controller according to the PID flow value. When the minimum stable time is reached, the human-computer interaction component 103 can output the PID flow value at this time as the leak rate of the system to be measured. By adopting the technical solution of this embodiment, there is no need to evacuate, the gas mass flow controller 104 with a range matching the pressure of the system to be measured is selected, and dynamic adjustment is performed based on the PID control component 102, so that the leak rate of a flexible material system or a low-pressure resistance system can be quickly detected, fully meeting the timeliness requirements of mass production.

[0069] The present invention also provides a leak rate measurement system based on the gas mass flow control technology. Figure 4 FIG. is a schematic structural diagram provided by an embodiment of the leak rate measurement system based on the gas mass flow control technology of the present invention. Please refer to Figure 4 , this embodiment includes a gas source 21 and the leak rate measurement device 22 based on the gas mass flow control technology described in the above embodiment. The gas source 21 is connected to the leak rate measurement device 22 based on the gas mass flow control technology, and the leak rate measurement device 22 based on the gas mass flow control technology is also connected to the system to be measured 23.

[0070] By adopting the technical solution of this embodiment, there is no need to evacuate, the gas mass flow controller 104 with a range matching the pressure of the system to be measured 23 is selected, and dynamic adjustment is performed based on the PID control component 102, so that the leak rate of a flexible material system or a low-pressure resistance system can be quickly detected, fully meeting the timeliness requirements of mass production.

[0071] It can be understood that the same or similar parts in the above embodiments can be referred to each other, and the content not detailed in some embodiments can be referred to the same or similar content in other embodiments.

[0072] It should be noted that in the description of the present invention, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of the present invention, unless otherwise specified, the meaning of "a plurality" refers to at least two.

[0073] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples", etc., mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0074] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A leak rate measurement device based on gas mass flow control technology, applicable to flexible material systems or low-pressure resistance systems, characterized in that, It includes a cabinet shell, a pressure monitoring component, a PID control component, a human-machine interaction component, and several gas mass flow controllers with increasing ranges, which are respectively arranged inside the cabinet shell; The inlet end of the gas mass flow controller is used to be connected to a gas source through a first pipeline, and the outlet end of the gas mass flow controller is used to be connected to a system under test through a second pipeline. The gas mass flow controller is used to control the inflation flow rate of the system under test; The pressure monitoring component is arranged at the system under test, and the pressure monitoring component is used to monitor a first pressure value inside the system under test; The PID control component is electrically connected to the pressure monitoring component and the gas mass flow controller respectively; The PID control component is used to perform PID control according to the first pressure value and a second pressure value pre-input by a tester through the human-machine interaction component, and output a PID flow rate value; The PID control component is further used to determine a target gas mass flow controller whose range matches the PID flow rate value, and dynamically adjust the opening degree of the target gas mass flow controller according to the PID flow rate value until a preset minimum stable time is reached; The human-machine interaction component is used to output the PID flow rate value corresponding to the minimum stable time as the leak rate of the system under test; A stop valve is arranged between each gas mass flow controller and the system under test; The stop valve is electrically connected to the PID control component; The stop valve is used to cut off the gas path of the corresponding gas mass flow controller, and avoid micro-leakage caused by the gas mass flow controller being in a cut-off state, thus causing errors.

2. The leak rate measuring device based on the gas mass flow control technology according to claim 1, characterized in that A high-pressure manual stop valve is arranged at the outlet of the gas source, and the stop control knob of the high-pressure manual stop valve is arranged on the cabinet shell; 3. The leak rate measuring device based on the gas mass flow control technology according to claim 1, wherein A pressure reducing valve is arranged at the inlet of the gas mass flow controller; The pressure reducing valve is used to reduce the pressure of the gas output by the gas source; 4. The leak rate measuring device based on the gas mass flow control technology according to claim 1, characterized in that, The human-machine interaction component is a touch screen; The touch screen is embedded on one side of the cabinet shell; 5. The leak rate measuring device based on the gas mass flow control technology according to claim 1, wherein The pressure monitoring component and the PID control component interact through digital signals; 6. The leak rate measuring device based on the gas mass flow control technology according to claim 1, characterized in that, A one-way valve is arranged on the first pipeline and / or the second pipeline; 7. The leak rate measuring device based on the gas mass flow control technology according to claim 1, characterized in that, The pressure monitoring component is a high-precision pressure transmitter; 8. The leak rate measuring device based on the gas mass flow control technology according to claim 1, characterized in that, It further includes a reminder component; The reminder component is connected to the PID control component; The PID control component is used to control the reminder component to send out a non-conformance reminder if the leak rate is greater than a preset standard leak rate; 9. A leak rate measurement system based on gas mass flow control technology, characterized in that, It includes a gas source and a leak rate measuring device based on gas mass flow control technology according to any one of claims 1-8; The gas source is connected to the leak rate measuring device based on gas mass flow control technology.

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