Quick calibration control system and device for multi-stage multi-connected mass flow controller

Abstract

The invention discloses a rapid calibration control system and device for a multi-stage multi-connected mass flow controller. The system comprises a multi-stage shunting pipeline module, a central core control and regulation module, a digital monitoring and testing module and a safety protection module, independent pre-calibration is carried out on each electric flow distribution valve in a secondary pipeline, a flow model is established, and then the flow of each path is cooperatively controlled and regulated based on the model; batch synchronous closed-loop calibration of a plurality of parallel mass flow controllers is realized; the digital monitoring and testing module serves as a special testing device of the system, collects flow data in real time and feeds back the flow data to the control core, and the safety protection module serves as a state monitoring and protection unit of the system and achieves whole-process operation state monitoring. According to the invention, the problems of mutual interference and low efficiency of parallel flow calibration are solved, and the calibration consistency, precision and automation level are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fluid control or regulation systems, in particular to a multi-stage multi-connection mass flow controller rapid calibration control system and device. BACKGROUND

[0002] As the core component in the field of fluid control, the accuracy of the flow controller directly determines the operation quality of industrial production, scientific research experiments and other scenes. Before leaving the factory, the performance needs to be ensured to meet the standards through strict calibration, and the calibration process relies on reliable control or regulation systems, as well as supporting functional units and monitoring test devices. There are many problems to be solved in the existing calibration-related control / regulation systems: the control / regulation system corresponding to the traditional calibration equipment mostly adopts single-channel or a small number of multi-channel architecture, the functional unit configuration is single, lacks the collaborative control mechanism required for batch calibration, the number of single calibration is limited, and when facing batch production demand, the calibration period is too long to match the production rhythm; although some multi-connection calibration schemes attempt to realize multi-device synchronous calibration, the corresponding control / regulation system does not optimize the cooperation of functional units, does not design precise regulation mechanisms for pipeline resistance differences and uneven fluid distribution, and the monitoring test device coverage is not complete, resulting in poor consistency of the calibration accuracy of mass flow controllers at different workstations, frequent secondary rework, and increased production costs; the monitoring test device corresponding to the detection link generally adopts full detection mode, which is single in function, consumes a large amount of time and standard gas, and relies on manual analysis of detection data, lacking efficient digital monitoring and batch judgment functional units. The disclosed multi-connection calibration-related control / regulation systems mostly focus on basic parallel architecture design, and do not solve the problems of independent pre-calibration control of valves, collaborative regulation based on flow uniformity, and optimization of monitoring test functional units corresponding to batch error estimation, which cannot balance the calibration efficiency, accuracy and detection cost, and cannot meet the needs of large-scale, high-precision mass flow controller calibration for control / regulation systems and their functional units and monitoring test devices. Therefore, there is an urgent need for a technical solution that optimizes the control / regulation system architecture, perfects the functional unit configuration, and strengthens the monitoring and testing capabilities. SUMMARY

[0003] The purpose of the present application is to provide a multi-stage multi-connection mass flow controller rapid calibration control system and device, which has the advantages of improving calibration efficiency, ensuring batch calibration accuracy consistency, and reducing detection cost.

[0004] The present application provides a multi-stage multi-connection mass flow controller rapid calibration control system, which comprises a multi-stage shunt pipeline module, a central core control and regulation module, a digital monitoring and testing module, and a safety protection module. The multi-stage shunt pipeline module comprises a primary pipeline, a secondary shunt pipeline and a tertiary shunt pipeline connected in series; wherein the primary pipeline is used for connecting a standard gas source and is provided with a pressure stabilizing and standard flow detection unit; the secondary shunt pipeline is provided with a plurality of independent branches, each branch being provided with a controllable electric precise flow distribution valve; the tertiary shunt pipeline comprises a plurality of parallel branches, each branch being provided with a to-be-calibrated mass flow controller interface; The central core control and adjustment module is electrically connected with the electric precise flow distribution valve and the to-be-calibrated mass flow controller, respectively, and is used for controlling the electric precise flow distribution valve to perform independent pre-calibration and cooperatively controlling the flow of each branch based on the pre-calibration result to realize batch synchronous calibration of the to-be-calibrated mass flow controller. The digital monitoring and testing module comprises a plurality of digital flow detection units connected to the output ends of the to-be-calibrated mass flow controllers, respectively, and is used for collecting actual output flow data of each controller in real time and transmitting the actual output flow data to the central core control and adjustment module. The safety protection module comprises a pressure sensor and / or an overload protection unit arranged at key nodes of the pipelines at different levels, and is used for monitoring system pressure and operating state and performing a safety protection action when an abnormality occurs.

[0005] Further, the central core control and adjustment module is provided with a fault diagnosis unit, the fault diagnosis unit is electrically connected with a pressure detection component of the standard gas source interface, a state detection component of the electric precise flow distribution valve, a communication detection component of the digital detection unit and a current detection component of the to-be-calibrated mass flow controller, respectively, the touch display unit is used for displaying a fault position, a fault type and troubleshooting suggestions, the central core control and adjustment module is provided with an audible and visual alarm component, and the central core control and adjustment module has a function of storing calibration data when a fault occurs.

[0006] Further, according to a preset interval range of a calibration range, the number of calibration points is set as a number containing a zero point and a full-scale point, and the central core control and adjustment module is imported with initialization parameters corresponding to a gas type parameter, a calibration range and a number of calibration points.

[0007] Further, the standard flow detection unit of the primary pipeline is a standard flow sensor, a control signal of the electric precise flow distribution valve and a feedback signal of the standard flow sensor constitute a closed loop, and the closed loop is used for pre-calibration of the electric precise flow distribution valve.

[0008] Further, the safety protection module further comprises a safety valve arranged at the primary pipeline and / or the secondary shunt pipeline, a detection signal of the pressure sensor is input to the central core control and adjustment module, and the central core control and adjustment module is used for linkage control of the precise pressure stabilizing valve.

[0009] In a second aspect, the present application further provides a multi-stage multi-connection mass flow controller fast calibration control device, comprising the multi-stage multi-connection mass flow controller fast calibration control system according to any one of the preceding aspects, wherein the device comprises a housing; the housing is internally arranged in a multi-layer layout structure, wherein the upper layer is provided with the multi-stage shunt pipeline module, the middle layer is provided with the central core control and adjustment module and the digital monitoring and testing module, and the lower layer is provided with the safety protection module; The housing is integrated with a standard gas source interface, a mass flow controller installation interface and a data interface, the standard gas source interface is connected with the multi-stage shunt pipeline module, the mass flow controller installation interface is connected with the multi-stage shunt pipeline module, and the data interface is electrically connected with the central core control and adjustment module.

[0010] Further, the housing is provided at the bottom with a support component with a moving and fixing function, and the device is further integrated with a wireless communication module for data interaction and remote monitoring with an external terminal.

[0011] Further, a pressure regulator is arranged on each branch of the three-stage shunt pipeline, and the pressure regulator is connected with the central core control and adjustment module.

[0012] Further, the device further comprises a housing sealing unit comprising a clean gas generator and a particulate matter sensor, the clean gas generator is in communication with the internal space of the housing, and the particulate matter sensor is connected with the central core control and adjustment module.

[0013] In a third aspect, the present application further provides a multi-stage multi-connection mass flow controller fast calibration control method, applied to the multi-stage multi-connection mass flow controller fast calibration control system or the multi-stage multi-connection mass flow controller fast calibration control device according to any one of the preceding aspects, and comprising the following steps: In the state of closing all the to-be-calibrated mass flow controllers at the downstream, the flow distribution valves of each branch of the secondary shunt pipeline are independently adjusted, and the flow characteristic model of each valve is established according to the upstream standard flow; Based on the pre-calibration model, the flow of each branch is cooperatively controlled, stable calibration flow is provided for the plurality of to-be-calibrated mass flow controllers connected simultaneously, and the output flow is collected for deviation calculation and correction; The calibrated mass flow controllers are grouped and sampled for detection, the calibration errors of the remaining controllers in the same group are inferred by using the sampling data and the pipeline flow fluctuation, and the batch calibration result is determined.

[0014] The present application has the beneficial effects that: First, in order to solve the problem that the existing calibration control system is difficult to meet the batch and high consistency calibration requirements, the application innovatively adopts the technical path of "valve pre-calibration-collaborative control-batch calibration". The central core control adjustment module first calibrates the flow characteristics of multiple electric precise flow distribution valves in the secondary shunt pipeline independently, and establishes an accurate flow-control instruction mapping model, which fundamentally solves the problem of uneven flow distribution and inconsistent calibration reference caused by the characteristic differences of the flow distribution valves in the multi-parallel calibration control system. Based on the pre-calibration model, the system can collaboratively and accurately control multiple calibration branches, ensuring that each mass flow controller to be calibrated receives stable, accurate and consistent input flow conditions. Combined with the high-resolution digital monitoring test module for real-time flow collection and deviation feedback, the central core control adjustment module can independently correct each controller in a closed loop, and finally realizes high-precision and high-consistency synchronous batch calibration of multiple mass flow controllers, significantly improving the calibration efficiency and the reliability of the results.

[0015] Second, in order to solve the problem of low integration, complex operation and poor field adaptability of existing calibration devices, the application has highly integrated the above-mentioned calibration control system in a modular and structurally optimized case. The device shell adopts a multi-layer layout design, with pipeline modules, control modules, detection modules and safety protection modules arranged in separate zones, ensuring the regularity of internal gas circuits and circuits, and improving reliability and maintenance convenience. By integrating standardized gas interfaces, controller interfaces, data interfaces and safety control components, the device realizes rapid deployment and connection. Combined with built-in fault diagnosis, safety interlock protection (such as pressure monitoring and overload cutoff) and optional wireless communication functions, the device not only greatly simplifies the operation process of field calibration and reduces the personnel operation threshold, but also enhances the adaptability and safety in different environments in the industrial field, truly realizing the transformation from laboratory precision equipment to efficient and reliable tools in the field. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, a brief introduction will be given below to the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the application, and for those skilled in the art, other drawings can be obtained from the structures shown in the drawings without creative labor.

[0017] Figure 1 A schematic diagram of the multi-stage multi-parallel mass flow controller rapid calibration control system of the application; Figure 2 A structural diagram of the multi-stage multi-parallel mass flow controller rapid calibration control device of the application; Figure 3The figure shows the working steps of the rapid calibration control method of the multi-stage multi-connection mass flow controller of the present application.

[0018] BRIEF DESCRIPTION OF DRAWINGS: 1, multi-stage shunt pipeline module; 2, central core control adjustment module; 3, digital monitoring test module; 4, safety protection module. DETAILED DESCRIPTION

[0019] In order for those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0020] The terms "first", "second", etc. in the specification and claims of the present application and the above drawings are used to distinguish different objects, not to describe a specific order. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, device, product or end including a series of steps or units is not limited to the listed steps or units, but can optionally include steps or units not listed, or can optionally include other steps or units inherent to the process, method, product or end.

[0021] In this paper, the term "embodiment" means that the specific features, structures or characteristics described in conjunction with the embodiment can be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment independent of or alternative to other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0022] In the prior art, the calibration process of the mass flow controller generally faces the problems of low efficiency and insufficient accuracy. The traditional calibration equipment is limited by single-channel architecture and cannot meet the batch production demand. The multi-connection calibration scheme can improve efficiency but has the problem of uneven fluid distribution, resulting in poor consistency of calibration results. The full-range detection mode consumes a lot of resources and the efficiency of manual analysis is low, which is difficult to adapt to large-scale calibration scenarios. Some schemes try to optimize the pipeline structure, but do not solve the problems of valve control accuracy and batch error estimation, which restricts the balance between calibration efficiency and cost.

[0023] In order to solve the above technical problems, with reference to Figure 1The application provides a multi-stage multi-connection mass flow controller rapid calibration control system, which comprises a multi-stage shunt pipeline module, a central core control and adjustment module, a digital monitoring and testing module and a safety protection module. The multi-stage shunt pipeline module 1 comprises a first-stage main pipeline, a second-stage shunt pipeline and a third-stage shunt pipeline connected in series; the first-stage main pipeline is used for connecting a standard gas source and is provided with a voltage stabilizing and standard flow detection unit; the second-stage shunt pipeline is provided with a plurality of independent branches, and each branch is provided with a controllable electric precise flow distribution valve; and the third-stage shunt pipeline comprises a plurality of parallel branches, and each branch is provided with a mass flow controller interface to be calibrated. The central core control and adjustment module 2 is electrically connected with the electric precise flow distribution valve and the mass flow controller to be calibrated respectively, is used for controlling the electric precise flow distribution valve to perform independent pre-calibration, and cooperatively controls the flow of each branch based on the pre-calibration result to realize batch synchronous calibration of the mass flow controller to be calibrated. The digital monitoring and testing module 3 comprises a plurality of digital flow detection units connected to the output ends of the mass flow controllers to be calibrated respectively, is used for collecting the actual output flow data of each controller in real time and transmitting the actual output flow data to the central core control and adjustment module. The safety protection module 4 comprises pressure sensors and / or overload protection units arranged at key nodes of the pipelines at various stages, is used for monitoring the system pressure and operating state, and performs a safety protection action when an abnormality occurs.

[0024] It should be noted that in some embodiments, the multi-stage shunt pipeline module 1 constitutes the physical basis of the system, which includes a primary pipeline, a secondary shunt pipeline and a tertiary shunt pipeline connected in series. The primary pipeline is the gas source inlet, which integrates a precision pressure stabilizing valve and a standard flow sensor. The former is used to stabilize the upstream gas source pressure at a preset constant value, and the latter is used to accurately measure the total gas flow through the primary pipeline. The secondary shunt pipeline is composed of several (e.g. 4, 8, etc.) independent branches connected in parallel, each of which is equipped with an electrically operated precision flow distribution valve that can receive control signals and accurately adjust the opening of the branch. Each secondary branch is connected downstream to multiple (e.g. 4 per secondary branch) tertiary shunt branches, each of which is provided with a quick connector for connecting a mass flow controller (MFC) to be calibrated. This "one-to-many" tree-like pipeline structure constitutes the basis of the batch calibration station. The central core control and adjustment module is the core of the entire system, usually composed of an industrial programmable logic controller (PLC), a human-machine interaction touch screen and related control software. The PLC is connected to the control end of each electrically operated precision flow distribution valve and each MFC to be calibrated through digital or analog signal cables. One of its core functions is to perform "pre-calibration" of the flow distribution valve: before calibration begins, all MFCs to be calibrated are closed, and by controlling the individual actions of the valves in the secondary pipeline and combining the feedback of the primary pipeline standard flow sensor, a mathematical model of "control instruction-actual flow" for each valve is established. Another core function is to provide consistent flow conditions that meet the calibration point requirements simultaneously and accurately for the input ends of dozens or even hundreds of MFCs to be calibrated based on this model during formal calibration. The digital monitoring and testing module is responsible for collecting the final output data, which includes multiple independent high-precision digital flow meters, each connected to the output end of an MFC to be calibrated. These flow meters collect real-time gas flow data after MFC adjustment and transmit the data to the central core control and adjustment module in real time through a high-speed data acquisition card. The safety protection module includes safety relief valves and pressure sensors distributed at key nodes such as the primary pipeline inlet and each secondary branch, as well as overload protectors connected to the MFC power supply circuit. The pressure sensor monitors the pipeline pressure in real time, and once the pressure exceeds, the signal is transmitted to the PLC to trigger an alarm or control the safety valve to act. The overload protection unit immediately cuts off the power supply of the MFC when it detects abnormal current, usually indicating valve failure or flow loss, to prevent damage.

[0025] Preferably, the central core control adjustment module 2 is embedded with a fault diagnosis unit, which is electrically connected with the pressure detection components of the standard gas source interface, the state detection components of the electric precise flow distribution valve, the communication detection components of the digital detection unit, and the current detection components of the MFC to be calibrated. The touch display unit is used to display the fault location, fault type, and troubleshooting suggestions. The central core control adjustment module is provided with an audible and visual alarm component, and has the function of storing the calibration data when the fault occurs.

[0026] In a preferred embodiment, a special fault diagnosis unit is also embedded in the central core control adjustment module 2. This unit monitors a plurality of key signal points in the system in real time. For example, it monitors whether the pressure of the standard gas source inlet is within the normal range through the pressure sensor; judges whether each electric precise flow distribution valve is stuck or damaged through valve feedback signal or current monitoring; judges whether the data link with each digital flow meter is unobstructed through communication state monitoring; and judges whether each MFC to be calibrated is working normally through monitoring the driving current. When the diagnosis module detects any abnormality, it will immediately display the fault location (for example, "No. 3 MFC of No. 2 secondary branch current overrun") on the touch screen in a graphical interface, and pop up a text description of the fault type and possible troubleshooting suggestions (for example, "check the line or replace the MFC"). At the same time, the audible and visual alarm configured by the system will start to remind the operator. In addition, the system will automatically save all the calibration data such as flow, pressure, valve opening at the moment when the fault occurs, forming a fault snapshot for subsequent analysis.

[0027] Preferably, according to the preset interval range of the calibration range, the number of calibration points is set to include the number of zero point and full scale point, and the central core control adjustment module imports the initialization parameters corresponding to the gas type parameters and the calibration range, the number of calibration points.

[0028] In a preferred embodiment, before actual operation, the parameters need to be preset in the man-machine interface of the central core control and adjustment module according to the model and specifications of the MFC to be calibrated. The operator needs to select or input the gas type (such as nitrogen, argon), because the physical parameters of different gases are different. Then, the calibration range needs to be set, for example, 0-500 sccm (standard cubic centimeter per minute). Then, the number of calibration points and their distribution need to be set. The number of calibration points is usually not less than 5, and must include the zero point and the full-scale point (i.e. 0 sccm and 500 sccm), and the intermediate points can be set according to the proportion or specific requirements, such as 10%, 30%, 50%, 70%, and 90% of the range. After these initialization parameters are loaded by the PLC, they will become the basis for subsequent automatic calibration processes (such as pre-calibration point setting, target flow rate giving, error determination threshold, etc.), so that the system can perform customized calibration for MFCs of different specifications.

[0029] Preferably, the standard flow detection unit of the primary main pipeline is a standard flow sensor, and the control signal of the electric precise flow distribution valve and the feedback signal of the standard flow sensor form a closed loop for pre-calibration of the electric precise flow distribution valve.

[0030] It should be noted that in the independent pre-calibration process of the flow distribution valve, it is crucial to form a high-precision closed-loop control link. In specific implementation, the central core control and adjustment module (PLC) sends an initial control instruction (such as a voltage signal) to a designated electric precise flow distribution valve. The change in valve opening causes a change in flow, which is reflected in the reading of the standard flow sensor in the primary main pipeline. The PLC continuously reads the real-time measurement value of the standard flow sensor and compares it with the target flow value of the current calibration point. If there is a deviation, the PLC will adjust the control instruction sent to the flow distribution valve in real time based on PID control algorithm, until the reading of the standard flow sensor stabilizes within a small allowed error range of the target value. The stable control instruction value at this time is recorded as the accurate control parameter of the valve at the current flow point. This "instruction-feedback-adjustment" closed-loop process is repeated at all pre-set calibration points of the valve, thereby establishing a high-precision flow characteristic model of the valve.

[0031] Preferably, the safety protection module further comprises a safety valve arranged in the primary main pipeline and / or the secondary shunt pipeline, and the detection signal of the pressure sensor is input to the central core control and adjustment module for linkage control of the precise pressure stabilizing valve.

[0032] It should be noted that in some embodiments, in addition to installing a safety valve at the key pipeline node as the final physical pressure relief guarantee, pressure sensors are also provided in the system, for example, installed after each branch of the secondary shunt pipeline or the primary main pipeline pressure stabilizing valve. The signals of these pressure sensors are transmitted to the central core control and adjustment module in real time. The central core control and adjustment module is provided with upper and lower safety limits of pressure. When the monitored pressure value exceeds the upper safety limit, the PLC will not only trigger an audible and light alarm, but also immediately output a control signal to actively close (or adjust) the precision pressure stabilizing valve at the front end of the primary main pipeline, or even close the upstream total gas source electromagnetic valve, to cut off or reduce the gas source supply from the source, to achieve active pressure suppression, rather than just post-pressure relief. This "monitoring-control" linkage can more quickly and more actively prevent abnormal pressure rise in the system, protecting the pipeline and precision valves.

[0033] Reference Figure 2 The application also provides an embodiment, a multi-stage multi-connection mass flow controller rapid calibration control device, comprising the multi-stage multi-connection mass flow controller rapid calibration control system according to any one of the embodiments. The device comprises a shell. The shell is internally provided with a multi-layer layout structure. The upper layer is provided with the multi-stage shunt pipeline module. The middle layer is provided with the central core control and adjustment module and the digital monitoring and testing module. The lower layer is provided with the safety protection module. The shell is integrated with a standard gas source interface, a mass flow controller installation interface and a data interface. The standard gas source interface is connected with the multi-stage shunt pipeline module. The mass flow controller installation interface is connected with the multi-stage shunt pipeline module. The data interface is electrically connected with the central core control and adjustment module.

[0034] An integrated multi-stage multi-parallel mass flow controller rapid calibration control device, in some embodiments, the aforementioned calibration control system is installed in a structured cabinet shell. The shell is usually in the form of a metal cabinet, and the internal space is divided into three clear physical layers: the upper layer is used to install multi-stage shunt pipeline modules, all gas pipelines, valves, joints are fixed on the installation plate, the gas path is clear, and it is convenient for inspection and maintenance. The middle layer is the electrical control area, which centrally installs the central core control and adjustment module (such as PLC cabinet, industrial computer, power supply, etc.) and digital monitoring and testing module (such as data acquisition card box, signal conditioner, etc.). The lower layer is installed with safety protection module components, such as main power switch, overload protector, safety valve exhaust guide pipe, etc. On the back or side of the shell, all external interfaces are integrated: the standard gas source interface is connected to the upper layer through the pipeline; a plurality of mass flow controller installation interfaces (quick plug-in connectors) are arranged on the panel and connected to the upper layer through internal pipelines; the data interface (such as Ethernet, USB, serial port, etc.) is connected to the central core control and adjustment module through a cable for program download, data export and external communication.

[0035] Preferably, the bottom of the shell is installed with a support component with moving and fixing functions, and the device is also integrated with a wireless communication module for data interaction and remote monitoring with external terminals.

[0036] In order to facilitate the movement and fixation of the calibration device between different working places (such as different stations of the production line, laboratory, repair area), the bottom of the device is installed with universal wheels with brake function and adjustable height support feet. When moving, it is easy to push through the universal wheels; after reaching the predetermined position, the support feet can be lowered and tightened to make the device stably supported on the ground, avoiding vibration during work. In addition, a wireless communication module (such as Wi-Fi or 4G / 5G module) is integrated in the device, which is connected to the communication port of the central core control and adjustment module. Through this module, the device can send real-time calibration progress, detection data of each MFC, device running state (pressure, temperature, alarm information, etc.) to the remote monitoring center or the engineer's mobile phone APP. At the same time, the monitoring center can also send instructions in the opposite direction, such as starting / stopping calibration, modifying calibration parameters, requesting data upload, etc., to realize remote monitoring and operation.

[0037] Preferably, a pressure regulator is arranged on each branch of the three-stage shunt pipeline, and the pressure regulator is connected to the central core control and adjustment module.

[0038] It should be noted that in some embodiments, a precision pressure regulator (or back pressure valve) is additionally arranged on each branch of the third shunt pipeline (i.e. before the inlet of each MFC to be calibrated). These pressure regulators are also controlled by the central core control and adjustment module. In the formal calibration process, in addition to cooperating with the flow distribution valve of the second pipeline to set the total flow, the central core control and adjustment module can also fine-tune these precision pressure regulators according to the feedback of the micro pressure sensor installed on the third branch (or the pressure estimated according to the theoretical model due to structural simplification). For example, even if the secondary distribution valve is accurately controlled, due to the slight differences in the flow resistance characteristics of each MFC, the inlet pressure of each MFC may still be slightly different. At this time, the central core control and adjustment module can independently adjust the pressure regulator on each third branch to make the pressure values at the inlets of each MFC to be calibrated highly consistent, thereby eliminating the calibration errors caused by the differences in inlet pressure and achieving higher precision parallel calibration.

[0039] Further, it further comprises a housing sealing unit, which comprises a clean gas generator and a particulate matter sensor, the clean gas generator being in communication with the internal space of the housing, and the particulate matter sensor being connected with the central core control and adjustment module.

[0040] Reference Figure 3 The application also provides an embodiment, a multi-stage multi-connection mass flow controller rapid calibration control method, applied to any one of the multi-stage multi-connection mass flow controller rapid calibration control system or any one of the multi-stage multi-connection mass flow controller rapid calibration control device, comprising the following steps: S1, independently adjusting the flow distribution valve of each branch in the second shunt pipeline in the state of closing all downstream mass flow controllers to be calibrated, and establishing a flow characteristic model of each valve according to the upstream standard flow; S2, based on the pre-calibration model, cooperating with the flow of each branch to provide stable calibration flow for multiple mass flow controllers to be calibrated, and collecting the output flow for deviation calculation and correction; S3, grouping and sampling detection of the calibrated mass flow controllers, and using the sampling data and pipeline flow fluctuation to infer the calibration error of the remaining controllers in the same group to determine the batch calibration result.

[0041] It should be noted that in the present embodiment, the first stage is valve pre-calibration: at the beginning of the calibration operation, all MFCs to be calibrated are not connected or are in the closed state. The central core control and adjustment module (PLC) controls each electrically operated precision flow distribution valve in the secondary shunt pipeline in turn and independently. For each valve, the PLC sends a control signal to it and reads the actual flow value at this time through the main pipeline standard flow meter, and records the data pair of "control instruction-actual flow". This process is repeated at a plurality of preset flow points (such as zero, 10%, 30%, 50%, 70%, 90%, and 100% of the full scale), thereby establishing an accurate flow characteristic calibration curve (i.e., a model) for each valve and storing it. The second stage is synchronous batch closed-loop calibration: connect a plurality of MFCs to be calibrated to the tertiary pipeline interface. The central core control and adjustment module calculates the cooperative control instruction according to the target flow point (for example, 100 sccm) set by the calibration program in combination with the characteristic model established for each secondary valve in the first stage, and sends it to all secondary valves at the same time. This makes all tertiary branches (i.e., the inlets of all MFCs) simultaneously obtain a stable and highly consistent 100 sccm flow input. Then, the control function of the MFC itself is turned on, and the actual output value of each MFC is read in real time through the downstream digital flow detection unit. The central core control and adjustment module compares the actual output value of each MFC with 100 sccm and calculates the percentage error. For MFCs with errors exceeding the allowed range (such as ±1%), the PLC sends a correction instruction to it through its communication interface (such as an analog voltage or digital communication) to adjust its internal parameters, so that its output approaches the target value. This process is repeated until the errors of all MFCs at the current point meet the standard. Then, the system automatically switches to the next flow point (such as 200 sccm) and repeats the process until the calibration of all preset points is completed. The third stage is sample presumption verification: after completing the full-point calibration of all MFCs, instead of performing full-range rechecking one by one, a statistical method is used for efficiency verification. All MFCs are grouped according to the secondary branch to which they are connected. In each group, a certain percentage of samples (such as 20%) are randomly selected. For these sample MFCs, a complete full-range high-precision detection is performed again. The maximum deviation, average deviation, and standard deviation of the deviation of these samples within the range are calculated. At the same time, the system retrieves the flow fluctuation data of the corresponding secondary branch recorded during the calibration process. Combined with the measured statistical data of the samples and the flow fluctuation data of the branch, the calibration error range of the remaining MFCs in the group that are not detected can be estimated through a preset error presumption formula. If the estimation result shows that the errors of all undetected MFCs are also within the qualified range with a high probability, it can be determined that all MFCs in this batch are calibrated to be qualified. This method greatly shortens the time of batch verification while ensuring the reliability of the conclusion.

[0042] The device embodiments described above are only illustrative, wherein the modules described as separate components can or can not be physically separated, and the components displayed as modules can or can not be physical modules, i.e., can be located in one place or can be distributed to multiple network modules. Part or all of the modules can be selected to achieve the purposes of the embodiments according to actual needs. Those skilled in the art can understand and implement without creative labor.

[0043] Finally, it should be noted that: the multi-stage multi-connection mass flow controller rapid calibration control system and device disclosed by the embodiments of the application are only the preferred embodiments of the application, and are used to illustrate the technical solutions of the application, but not to limit them; although the application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that; the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the application.

Claims

1. A multi-stage multi-parallel mass flow controller fast calibration control system, characterized in that, The multi-stage shunt pipeline module, the central core control and adjustment module, the digital monitoring and testing module, and the safety protection module, The multi-stage shunt pipeline module comprises a first-stage main pipeline, a second-stage shunt pipeline and a third-stage shunt pipeline connected in series; the first-stage main pipeline is configured to connect a standard gas source and is provided with a pressure stabilizing and standard flow detection unit; the second-stage shunt pipeline is provided with a plurality of independent branches, each branch being provided with a controllable electric precise flow distribution valve; and the third-stage shunt pipeline comprises a plurality of parallel branches, each branch being provided with a to-be-calibrated mass flow controller interface; The central core control and adjustment module is electrically connected with the electric precise flow distribution valve and the to-be-calibrated mass flow controller, respectively, and is configured to control the electric precise flow distribution valve to perform independent pre-calibration and cooperatively control the flow of each branch based on the pre-calibration result, and to perform batch synchronous calibration on the to-be-calibrated mass flow controller; The digital monitoring and testing module comprises a plurality of digital flow detection units connected to the output ends of the to-be-calibrated mass flow controllers, respectively, and is configured to collect actual output flow data of each controller in real time and transmit the data to the central core control and adjustment module to provide data support for control and adjustment; The safety protection module comprises pressure sensors and / or overload protection units arranged at key nodes of the pipelines at different stages, and is configured to monitor system pressure and operating state and perform a safety protection action when an abnormality occurs.

2. The multi-stage multi-parallel mass flow controller fast calibration control system of claim 1, wherein, The central core control and adjustment module is provided with a fault diagnosis unit, the fault diagnosis unit is electrically connected with a pressure detection component of a standard gas source interface, a state detection component of an electric precise flow distribution valve, a communication detection component of a digital detection unit, and a current detection component of a to-be-calibrated mass flow controller, a touch display unit is configured to display a fault position, a fault type and troubleshooting suggestions, the central core control and adjustment module is provided with an audible and visual alarm component, and the central core control and adjustment module has a function of storing calibration data when a fault occurs.

3. The multi-stage multi-parallel mass flow controller fast calibration control system of claim 1, wherein, According to a preset interval range of a calibration range, the number of calibration points is set to include zero points and full-scale points, and the central core control and adjustment module is imported with initialization parameters corresponding to a gas type parameter, a calibration range and a number of calibration points.

4. The multi-stage multi-parallel mass flow controller fast calibration control system of claim 1, wherein, The standard flow detection unit of the first-stage main pipeline is a standard flow sensor, a control signal of the electric precise flow distribution valve and a feedback signal of the standard flow sensor constitute a closed loop, and the closed loop is used for pre-calibration of the electric precise flow distribution valve.

5. The multi-stage multi-parallel mass flow controller fast calibration control system of claim 1, wherein, The safety protection module further comprises a safety valve arranged in the first-stage main pipeline and / or the second-stage shunt pipeline, a detection signal of the pressure sensor is input to the central core control and adjustment module, and the safety valve is used for linkage control of a precise pressure stabilizing valve.

6. A multi-stage multi-parallel mass flow controller fast calibration control device, characterized in that, The device comprises a shell, a multi-layer layout structure is adopted inside the shell, an upper layer of the multi-layer layout structure is provided with the multi-stage shunt pipeline module, a middle layer of the multi-layer layout structure is provided with the central core control and adjustment module and the digital monitoring and testing module, and a lower layer of the multi-layer layout structure is provided with the safety protection module. The shell is integrated with a standard gas source interface, a mass flow controller installation interface and a data interface, the standard gas source interface is connected with the multi-stage shunt pipeline module, the mass flow controller installation interface is connected with the multi-stage shunt pipeline module, and the data interface is electrically connected with the central core control and adjustment module.

7. The multi-stage multi-parallel mass flow controller fast calibration control device according to claim 6, wherein, The bottom of the shell is provided with a support component with moving and fixing functions, and the device is further integrated with a wireless communication module for data interaction with an external terminal and remote monitoring.

8. The multi-stage multi-parallel mass flow controller fast calibration control device of claim 6, wherein, A pressure regulator is arranged on each branch of the three-stage shunt pipeline, and the pressure regulator is connected with the central core control and adjustment module.

9. The multi-stage multi-parallel mass flow controller fast calibration control device of claim 6, wherein, The shell sealing unit includes a clean gas generator and a particulate matter sensor, the clean gas generator is communicated with the internal space of the shell, and the particulate matter sensor is connected with the central core control and adjustment module.

10. A method for fast calibration control of a multi-stage multi-parallel mass flow controller, characterized in that, The application is applied to the multi-stage multi-connection mass flow controller rapid calibration control system of any one of claims 1-5 or the multi-stage multi-connection mass flow controller rapid calibration control device of any one of claims 6-9, and includes the following steps: In the state of closing all to-be-calibrated mass flow controllers downstream, the flow distribution valves of each branch of the secondary shunt pipeline are independently adjusted, and the flow characteristic model of each valve is established according to the upstream standard flow; Based on the pre-calibration model, the flow of each branch is controlled, stable calibration flow is provided for multiple to-be-calibrated mass flow controllers, and the output flow is collected for deviation calculation and correction; The calibrated mass flow controllers are grouped and sampled, the calibration errors of the remaining controllers in the same group are inferred by using the sampling data and the pipeline flow fluctuation, and the batch calibration result is determined.

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