Gas mass flow servo control device and control method

Abstract

The application provides a gas mass flow servo control device and a control method, which comprises a gas collecting pipe, an inlet electromagnetic valve group, an exhaust electromagnetic valve group, a pressure regulating valve and a regulator; the gas collecting pipe is sealedly connected with the inlet electromagnetic valve group, the exhaust electromagnetic valve group and the pressure regulating valve to provide a gas storage space with stable gas pressure; supersonic nozzles in the inlet electromagnetic valve group and the exhaust electromagnetic valve group are installed on the two sides of the gas collecting pipe in a split manner, and the on-off states are opposite, so that the required gas mass flow of a gas using device is provided while the gas pressure in the gas collecting pipe is kept stable; the regulator determines the current gas mass flow, the theoretical pressure of the gas collecting pipe at the next moment and the on-off combination of all supersonic nozzles in the inlet and exhaust electromagnetic valve groups, and drives the actuator to act. The application overcomes the problems of discontinuous data, large overshoot, long response time and large steady-state error during the regulation of the gas mass flow, and has the characteristics of simple structure, high automation and intelligence and good system stability.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of plasma technology and aerodynamic heating test, and particularly relates to a gas mass flow follow-up control device and a control method. BACKGROUND

[0002] A plasma generator is a kind of high-efficiency energy conversion device that converts electrical energy into internal energy of gas, and is widely used in many fields such as national defense, industrial production and environmental governance. During the operation of the plasma generator, the gas flow entering the plasma generator needs to be accurately controlled, and sometimes it is even necessary to track a continuously changing gas mass flow curve in real time to achieve the purpose of fine control of the output flow field of the generator.

[0003] The sonic nozzle, also known as the Venturi nozzle, has a gas flow passage in the shape of a horn mouth with a wide end and a narrow middle. When a certain pressure ratio is formed between the upstream and downstream, the minimum cross section of the sonic nozzle is exactly the sonic speed. According to this feature, the downstream gas mass flow can be accurately controlled. Currently, the gas mass flow control of the plasma generator is mainly realized through the following two ways: one is to change the minimum cross section of the sonic nozzle, and the other is to use a pressure regulating valve to control the upstream pressure of the sonic nozzle.

[0004] One of the methods to change the minimum cross section of the sonic nozzle is to design a sonic nozzle with a variable minimum cross section, combined with a control method for changing the minimum cross section. This method requires a very complex nozzle structure design. Some studies have proposed using electromagnetic valves to select sonic nozzles with different throat areas to achieve dynamic regulation of gas flow. However, this method of changing the throat area of the sonic nozzle needs to set up a large number of nozzles to meet the continuously changing simulation conditions. Using a pressure regulating valve to regulate the upstream pressure of the sonic nozzle, when the gas mass flow changes in a large range, the pressure at the output end of the pressure regulating valve has the problems of long response time, large overshoot and large steady-state error. Although there are patents that provide a three-stage pressure regulating solution to solve the problem of large pressure regulation, the overall control speed and accuracy are still difficult to meet the high-level demand for fast and high-precision regulation. SUMMARY

[0005] In order to overcome the deficiencies in the prior art, the present inventors have made intensive research and provided a gas mass flow follow-up control device and a control method, which solve the problems of long response time, large overshoot and large dynamic error of a single pressure regulating valve when regulating the gas of a plasma generator and other gas equipment, and the problem that a single electromagnetic valve cannot continuously regulate the flow.

[0006] The technical solutions provided by the present application are as follows:

[0007] In a first aspect, a gas mass flow follow-up control device includes a gas collecting pipe, an inlet electromagnetic valve group, an exhaust electromagnetic valve group, a pressure regulating valve and a regulator.

[0008] The gas collecting pipe is sealed with the intake electromagnetic valve group, the exhaust electromagnetic valve group and the pressure regulating valve, and is used for providing a gas storage space with stable pressure;

[0009] The intake electromagnetic valve group comprises multiple pairs of sealed electromagnetic valves and sonic nozzles, and the opening and closing states of the sonic nozzles are adjusted by the electromagnetic valves, so as to provide the gas using equipment with required gas mass flow;

[0010] The exhaust electromagnetic valve group comprises multiple pairs of sealed electromagnetic valves and sonic nozzles, and the opening and closing states of the sonic nozzles are adjusted by the electromagnetic valves, so as to keep the gas pressure in the gas collecting pipe stable when the opening and closing states of the sonic nozzles in the intake electromagnetic valve group change;

[0011] The pressure regulating valve is sealed with the gas collecting pipe, and is used for regulating the gas pressure entering the gas collecting pipe;

[0012] The regulator is used for determining the gas mass flow flowing into the gas using equipment at the current time, the theoretical pressure of the gas collecting pipe at the next time and the opening and closing combination of all the sonic nozzles in the intake electromagnetic valve group and the exhaust electromagnetic valve group according to preset gas mass flow track data, the measured pressure in the gas collecting pipe at the current time and the opening and closing combination state data of all the sonic nozzles in the intake electromagnetic valve group and the exhaust electromagnetic valve group, and driving the intake electromagnetic valve group, the exhaust electromagnetic valve group and the pressure regulating valve to execute the opening and closing or pressure adjustment of the sonic nozzles.

[0013] In the second aspect, a gas mass flow follow-up control method is implemented by the gas mass flow follow-up control device in the first aspect, and comprises the following steps:

[0014] The type and number of the sonic nozzles in the intake electromagnetic valve group are determined according to the range of the gas mass flow to be regulated and the optimal pressure regulating upper and lower limits of the pressure regulating valve;

[0015] The type and number of the sonic nozzles in the exhaust electromagnetic valve group are determined according to the type and number of the sonic nozzles in the intake electromagnetic valve group;

[0016] The characteristic vector of the sonic nozzles in the intake electromagnetic valve group is constructed according to all the opening and closing items of each sonic nozzle in the intake electromagnetic valve group and the minimum value and the maximum value of the gas mass flow corresponding to the opening and closing item combination;

[0017] The gas mass flow flowing into the gas using equipment at the current time is determined according to the measured pressure signal in the gas collecting pipe at the current time and the opening and closing combination state data of each sonic nozzle, the theoretical pressure of the gas collecting pipe at the next time and the opening and closing combination of all the sonic nozzles in the intake electromagnetic valve group and the exhaust electromagnetic valve group are determined according to preset gas mass flow track data and the characteristic vector of the sonic nozzles in the intake electromagnetic valve group, and the intake electromagnetic valve group, the exhaust electromagnetic valve group and the pressure regulating valve are driven to execute the opening and closing or pressure adjustment of the sonic nozzles.

[0018] The gas mass flow servo control device and control method provided by the present application has the following advantages

[0019] Advantages:

[0020] (1) The gas mass flow servo control device and control method provided by the present application can complete the fast calculation and adjustment of the gas mass flow by using the DSP embedded system of the regulator, so as to ensure the fast comprehensive calculation and response speed of the gas mass flow adjustment.

[0021] (2) The gas mass flow servo control device and control method provided by the present application can realize the continuous wide-range gas mass flow coverage by using a limited number of sonic nozzles, so as to greatly reduce the complexity of the system and improve the reliability of the system.

[0022] (3) The gas mass flow servo control device and control method provided by the present application can quickly suppress the pressure fluctuation in the gas collecting pipe caused by the sonic switch of the inlet electromagnetic valve group during the adjustment of the gas mass flow.

[0023] (4) The gas mass flow servo control device and control method provided by the present application can automatically determine the required pressure regulation and sonic nozzle combination according to the real-time gas mass flow requirement, so as to realize the intelligent automatic adjustment of the gas mass flow without manual intervention.

[0024] (5) The gas mass flow servo control device and control method provided by the present application always selects the combination with the least switching frequency of the sonic nozzle when the gas flow of the plasma generator or other gas equipment is changed, so as to minimize the switching frequency of the electromagnetic valve and effectively avoid the dead zone overshoot phenomenon of the plasma generator or other gas equipment during the intermittent switching of different electromagnetic valves, thereby ensuring the smooth transition of the flow field. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 Fig. 1 is a schematic diagram of the gas mass flow servo control device of the present application;

[0026] Figure 2 Fig. 4 is a circuit principle block diagram of the gas mass flow regulator of the present application. DETAILED DESCRIPTION

[0027] The characteristics and advantages of the present application will become more apparent and explicit with the following detailed description of the present application.

[0028] The word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any implementation described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other implementations. Although various aspects of implementations can be presented in terms of methods, one should appreciate that such implementations can also be implemented as appropriate with any number of computer-readable storage media storing instructions for execution on one or more processors, or implemented as any number of software programs stored in any number of computer-readable storage media for execution on one or more processors.

[0029] According to a first aspect of the present application, there is provided a gas mass flow servo control device, as shown in the accompanying drawings, comprising a gas collecting pipe 1, an inlet gas solenoid valve group 2, an outlet gas solenoid valve group 3, a pressure regulating valve 4 and a regulator; Figure 1

[0030] The gas collecting pipe 1 is sealed and screwed with the inlet gas solenoid valve group 2, the outlet gas solenoid valve group 3 and the pressure regulating valve 4, for providing a gas pressure stable storage space;

[0031] The inlet gas solenoid valve group 2 comprises a plurality of pairs of solenoid valves and sonic nozzles (D1, D2, D3, D4…), the solenoid valves adjust the on-off state of the sonic nozzles to provide the required gas mass flow for plasma generator and other gas consuming devices; the solenoid valves and the sonic nozzles are sealed and screwed through necessary gas flow fittings, the number of pairs of solenoid valves and sonic nozzles is determined according to the range of gas mass flow to be adjusted;

[0032] The outlet gas solenoid valve group 3 comprises a plurality of pairs of solenoid valves and sonic nozzles (D1’, D2’, D3’, D4’…), the solenoid valves adjust the on-off state of the sonic nozzles to maintain the gas pressure stable in the gas collecting pipe when the on-off state of the sonic nozzles in the inlet gas solenoid valve group 2 changes; the solenoid valves and the sonic nozzles are sealed and screwed through necessary gas flow fittings, the number of pairs of solenoid valves and sonic nozzles is the same as that in the inlet gas solenoid valve group;

[0033] Preferably, the sonic nozzles in the inlet gas solenoid valve group 2 and the outlet gas solenoid valve group 3 are installed in two rows on both sides of the gas collecting pipe, and the diameters of the opposite sonic nozzles are the same, and the on-off states are opposite, for example, when the solenoid valve controls the sonic nozzle D1 to be in the open state, the opposite sonic nozzle D1’ is controlled by the solenoid valve to be in the closed state;

[0034] The pressure regulating valve 4 is sealed and screwed with the gas collecting pipe 1, for regulating the gas pressure entering the gas collecting pipe 1, and together with the inlet gas solenoid valve group 2 and the outlet gas solenoid valve group 3, adjusting the pressure in the gas collecting pipe;

[0035] ​The regulator is used to determine the gas mass flow into the gas equipment at the current time, the theoretical pressure of the gas collecting pipe at the next time, and the switch combination of all sonic nozzles in the intake electromagnetic valve group and the exhaust electromagnetic valve group according to the preset gas mass flow track data, the measured pressure in the gas collecting pipe at the current time, and the switch combination state data of all sonic nozzles in the intake electromagnetic valve group and the exhaust electromagnetic valve group, and drive the intake electromagnetic valve group 2, the exhaust electromagnetic valve group 3, and the pressure regulating valve 4 to execute the switch or pressure adjustment of the sonic nozzle.

[0036] In a preferred embodiment, the type and number of sonic nozzles in the intake electromagnetic valve group required for the gas entering the gas equipment such as the plasma generator are configured by the range of the gas mass flow to be adjusted and the optimal upper and lower boundaries of the pressure regulating valve.

[0037] Suppose the range of the gas mass flow to be adjusted is [G min ,G max ] g / s, the optimal working pressure range of the selected pressure regulating valve is [P min ,P max ] MPa, the number of sonic nozzles is n, and the diameter of the i-th sonic nozzle is D i (i = 1, 2, …, n).

[0038] The diameter of the first sonic nozzle should be q1 is the gas correlation coefficient, and when air is taken as the object of gas mass flow adjustment, q1 = 0.746;

[0039] To ensure that all values within the range of air mass flow can be continuously taken, the diameter of the i-th sonic nozzle should be D j is the diameter of the j-th sonic nozzle, j = 1, 2, …, i-1.

[0040] In addition, the number of the smallest sonic nozzles in the intake electromagnetic valve group should be The minimum n value that satisfies the inequality, and q2 is the gas correlation coefficient, and when air is taken as the object of gas mass flow adjustment, q2 = 1.796.

[0041] In a preferred embodiment, as shown in Figure 2 , the regulator comprises an operation and control module (such as a DSP circuit), an isolation module, a driving module, a protection module, and a human-computer interface; the operation and control module is connected with the isolation module, the driving module, and the protection module through data lines, and the operation and control module reads the preset gas mass flow track data from the human-computer interface through the data lines.

[0042] The isolation module is configured to receive a measured pressure signal of the gas collecting pipe 1 at a current time and switch combination state data of each supersonic nozzle, and transmit the switch combination state data to the operation and control module after level conversion.

[0043] The operation and control module is configured to determine a gas mass flow of the gas equipment at the current time according to the measured pressure signal of the gas collecting pipe at the current time and the switch combination state data of each supersonic nozzle, determine a gas collecting theoretical pressure at a next time and a switch combination of all supersonic nozzles in the intake electromagnetic valve group and the exhaust electromagnetic valve group according to preset gas mass flow track data, and distribute control instructions to the intake electromagnetic valve group 2, the exhaust electromagnetic valve group 3 and the pressure regulating valve 4 through the driving module, and transmit real-time gas mass flow data to the human-machine interface.

[0044] The protection module is configured to automatically disconnect the intake valve or power supply of the gas mass flow servo control device under the driving of the driving module when gas or electric overload occurs in the upstream gas supply equipment, the downstream gas equipment and the gas mass flow servo control device, so as to ensure the safety of the regulator.

[0045] In a preferred embodiment, the operation and control module determines the gas mass flow of the gas equipment at the current time according to the measured pressure signal of the gas collecting pipe at the current time and the switch combination state data of each supersonic nozzle, and is implemented by the following method:

[0046] Let S(i) be the switch state of the supersonic nozzle i in the intake electromagnetic valve group, 0 represents that the electromagnetic valve of the supersonic nozzle is closed, and 1 represents that the electromagnetic valve of the supersonic nozzle is opened, and the gas mass flow at the current time is Wherein, q2 is a gas correlation coefficient, q2 = 1.796 when air is taken as the object of gas mass flow adjustment; n is the number of supersonic nozzles, D i is the diameter of the i th supersonic nozzle, i = 1, 2, …, n; P0 is the measured pressure value in the gas collecting pipe at the current time.

[0047] In a preferred embodiment, the operation and control module determines the gas collecting theoretical pressure at the next time and the switch combination of all supersonic nozzles in the intake electromagnetic valve group and the exhaust electromagnetic valve group according to the preset gas mass flow track data, which includes:

[0048] Step 1, according to all switch items of each supersonic nozzle in the intake electromagnetic valve group, let S(i) be the switch state of the supersonic nozzle i in the intake electromagnetic valve group, 0 represents that the electromagnetic valve of the supersonic nozzle is closed, and 1 represents that the electromagnetic valve of the supersonic nozzle is opened, and an n+2-dimensional characteristic vector of the supersonic nozzle of the intake electromagnetic valve group is constructed, the first n items of the characteristic vector are the switch states of each supersonic nozzle in the intake electromagnetic valve group, and the last two items are the minimum value and the maximum value of the gas mass flow when the combination is made, that is, q2 is the gas correlation coefficient. When air is used as the object of gas mass flow rate regulation, q2 = 1.796.

[0049] The switching states of each sonic nozzle in the exhaust sonic valve assembly are reversed compared to the switching states of each sonic nozzle in the intake sonic valve assembly.

[0050] Step 2, let G be the gas mass flow rate that needs to be adjusted at time k. k Iterate through the combinations of sonic nozzle on / off states, and satisfy the last two conditions. The first n terms of the eigenvector are used as the gas mass flow rate G. k The sonic nozzle switch status, and simultaneously determine the current state. q3 is the gas correlation coefficient. When air is used as the object of gas mass flow rate regulation, q3 = 0.557.

[0051] If satisfied When there are multiple sonic nozzle switch combinations, the combination with the largest binary value is selected at the initial moment (k=1). During the voltage regulation phase (k≥2), the combination with the fewest sonic nozzle state changes compared to the previous moment is selected as the optimal solution for the current moment.

[0052] In a preferred embodiment, the arithmetic and control module uses TI's TMS320F28335 floating-point digital signal processor, and the clock uses a 30MHz active crystal oscillator. The clock circuit is connected in a 5x frequency control manner.

[0053] The isolation module uses a PC817 optocoupler to optically isolate the on / off combination status data of the sonic nozzle before communicating with the calculation and control module; the DAQM-4206C voltage and current acquisition module is used to isolate and convert the pressure signal in the gas collection pipe before communicating with the calculation and control module.

[0054] The drive module controls the switching of the solenoid valves in the intake solenoid valve group and the exhaust solenoid valve group through a relay circuit, and sends the required pressure value to the pressure regulating valve 4 through TI's D / A circuit.

[0055] According to a second aspect of the present invention, a method for controlling gas mass flow rate is also provided, comprising the following steps:

[0056] (1) Construction stage of the intake solenoid valve group of the control device.

[0057] By determining the range of gas mass flow rate that needs to be adjusted and the upper and lower limits of the optimal pressure regulation of the pressure regulating valve, the type and number of sonic nozzles for the intake solenoid valve assembly required for gas to enter gas-using equipment such as plasma generators are constructed.

[0058] Assume the range of gas mass flow rate that needs to be adjusted is: [G min G max], unit g / s, the selected pressure regulating valve's best working pressure range is [P min ,P max ], unit MPa, the number of sonic nozzles in the intake solenoid valve group is n, the diameter of the i th sonic nozzle is D i (i = 1, 2, …, n) ;

[0059] Then the diameter of the first sonic nozzle should be To ensure that all values within the range of air mass flow can be continuously taken, the diameter of the i th sonic nozzle should be D j D is the diameter of the j th sonic nozzle, j = 1, 2, …, i-1; q1 is the gas correlation coefficient, when air is taken as the object of gas mass flow regulation, q1 = 0.746.

[0060] In addition, the minimum number of sonic nozzles in the intake solenoid valve group is n The minimum n value that satisfies the inequality, q2 is the gas correlation coefficient, when air is taken as the object of gas mass flow regulation, q2 = 1.796.

[0061] (2) Exhaust solenoid valve group configuration stage of the control device.

[0062] To reduce the fluctuations in upstream pressure caused by the opening and closing of the intake solenoid valve group's sonic nozzles, corresponding exhaust solenoid valve group sonic nozzles need to be set. The number of sonic nozzles in the exhaust solenoid valve group is the same as that in the intake solenoid valve group in step (1), and the minimum diameter of each sonic nozzle is consistent with that of each sonic nozzle in the intake solenoid valve group. The same diameter sonic nozzles of the intake and exhaust solenoid valve groups are installed on both sides of the gas collecting pipe.

[0063] (3) Pressure regulating preparation stage. This stage obtains the characteristic vector of the intake solenoid valve group's sonic nozzles and stores it in the operation and control module.

[0064] According to all the opening and closing items of each sonic nozzle in the intake solenoid valve group, let S(i) be the opening and closing state of the i th sonic nozzle in the intake solenoid valve group, with 0 representing the closing of the electromagnetic valve of a certain sonic nozzle and 1 representing the opening of the electromagnetic valve of a certain sonic nozzle. At the same time, an n+2 dimensional characteristic vector of the intake solenoid valve group's sonic nozzles is constructed, with the first n items being the opening and closing states of each sonic nozzle in the intake solenoid valve group and the last two items being the minimum and maximum values of the gas mass flow when this combination is made, i.e. q2 is the gas correlation coefficient, when air is taken as the object of gas mass flow regulation, q2 = 1.796.

[0065] The n sonic nozzles in the intake solenoid valve group will construct 2 n-1 the above feature vector, all the sound velocity nozzle closed invalid combination. Out gas solenoid valve group in each sound velocity nozzle switch state and the intake solenoid valve group in each sound velocity nozzle switch state take opposite, in the intake solenoid valve group in each sound velocity nozzle switch state is determined, the out gas solenoid valve group in each sound velocity nozzle switch state is also determined.

[0066] (4) the current time gas mass flow, the next time each sound velocity nozzle switch state and the upstream manifold pressure value determination.

[0067] (i) according to the current time set gas pipe in the measured pressure signal and each sound velocity nozzle switch combination state data to determine the current time gas equipment of the gas mass flow, the specific method is: S(i) for sound velocity nozzle i switch state, 0 indicates that the solenoid valve of certain sound velocity nozzle is closed, 1 indicates that the solenoid valve of certain sound velocity nozzle is opened, the current time gas mass flow wherein, q2 is the gas correlation coefficient, when air as the object of gas mass flow regulation q2 = 1.796; N is the number of sound velocity nozzle, D i for the diameter of the i sound velocity nozzle, i = 1, 2,..., n; P0 current time set gas pipe in the measured pressure value.

[0068] (ii) the next time each sound velocity nozzle switch state and the upstream manifold pressure value determination method as follows:

[0069] denote k time need to adjust the gas mass flow for G k , traversal to find the sound velocity nozzle switch state combination, the last two items meet the feature vector of the first n as the sound velocity nozzle switch state of the gas mass flow G k ; At the same time determine the q3 is the gas correlation coefficient, when air as the object of gas mass flow regulation q3 = 0.557.

[0070] Generally meet the sound velocity nozzle switch combination may have more than one, the next time for the initial time (k = 1), select the combination of binary value maximum, under the combination of adjustable gas mass flow range is maximum; The next time for pressure regulating stage (k >= 2), select the sound velocity nozzle state transformation less than the previous time combination as the optimal solution of the current time.

[0071] The following is an example of the specific embodiment of the present application. The existing gas (air) mass flow range to be regulated is [10, 200] g / s. The selected pressure regulating valve has an optimal working pressure range of [7, 11] MPa. The intake solenoid valve group constructed according to step (1) is shown in Table 1, and the minimum and maximum gas mass flow that can be simulated by a single sonic nozzle is determined by the regulating range. Through the above construction, within the regulating working range, the required continuous regulation of the gas mass flow can be achieved by the combination of 4 sonic nozzles. Table 2 shows the gas mass flow that can be simulated by different arrangements within the regulating working range.

[0072] The number of sonic nozzles in the exhaust solenoid valve group is the same as that in the intake solenoid valve group, and the minimum diameter of each sonic nozzle is consistent with that of each sonic nozzle in the intake solenoid valve group. The sonic nozzles of the same diameter in the intake and exhaust solenoid valve groups are installed in two rows on the two sides of the collector.

[0073] The gas mass flow range at different times and the constructed intake solenoid valve group sonic nozzle feature vector are transmitted to the storage unit of the DSP through the human-machine interface.

[0074] Table 1: Simulation capability of a single sonic nozzle

[0075]

[0076] Table 2: Simulation capability of multiple sonic nozzle arrangements

[0077]

[0078]

[0079]

[0080] If the gas mass flow to be regulated at k = 1 is 50 g / s, the DSP traverses the intake solenoid valve group sonic nozzle feature vector, and it is known that arrangements 4, 5, and 6 can achieve 50 g / s gas mass flow regulation. According to the rules set in step (4), arrangement 6 is selected, and the required regulating pressure is 7.6 MPa. The sonic nozzle switch command sent by the DSP to the intake solenoid valve group through the driving module is (0, 1, 1, 0), the sonic nozzle switch command sent to the exhaust solenoid valve group is (1, 0, 0, 1), and the pressure regulating command sent to the pressure regulating valve is 7.6 MPa.

[0081] If the gas mass of 100g / s needs to be adjusted at k+1 moment, the DSP traverses the inlet solenoid valve group sonic nozzle eigenvector, and it is known that the arrangement combinations 8, 9 and 10 can all realize the gas mass flow adjustment of 100g / s. The DSP reads the sonic nozzle switch combination of the last moment (k moment) as (0, 1, 1, 0), determines that the combination 8 needs to change 3 times of the sonic nozzle state, the combination 9 needs to change 4 times of the sonic nozzle state, and the combination 10 needs to change 2 times of the sonic nozzle state. According to the rule set in step (4), the combination 10 is selected as the optimal solution result, and the required pressure regulating is about 7.5MPa. The DSP sends the sonic nozzle switch instruction to the inlet solenoid valve group through the driving module as (0, 1, 0, 1), sends the sonic nozzle switch instruction to the exhaust solenoid valve group as (1, 0, 1, 0), and sends the pressure regulating instruction to the pressure regulating valve as 7.5MPa.

[0082] The above detailed description of the present application is combined with the specific implementation and the exemplary examples, but these descriptions cannot be understood as the limitation of the present application. The person skilled in the art understands that the technical solutions and the implementation of the present application can be variously replaced, modified or improved without deviating from the spirit and scope of the present application, and these all fall within the scope of the present application. The protection scope of the present application is subject to the appended claims.

[0083] The contents not described in detail in the specification of the present application are the known technology of the person skilled in the art.

Claims

1. A gas mass flow rate follow-up control device, characterized in that, Includes air collection pipe, intake solenoid valve assembly, exhaust solenoid valve assembly, pressure regulating valve and regulator; The gas collecting pipe is sealed to the inlet solenoid valve group, the exhaust solenoid valve group, and the pressure regulating valve to provide a gas storage space with stable gas pressure. The intake solenoid valve assembly includes multiple pairs of sealed solenoid valves and sonic nozzles. The solenoid valves adjust the on / off state of the sonic nozzles to provide the required gas mass flow rate to the gas-using equipment. The exhaust solenoid valve assembly includes multiple pairs of sealed solenoid valves and sonic nozzles. The sonic valves adjust the switching state of the sonic nozzles to maintain stable gas pressure in the gas collection pipe when the switching state of the sonic nozzles changes in the intake solenoid valve assembly. The pressure regulating valve is sealed to the gas collecting pipe and is used to regulate the gas pressure entering the gas collecting pipe; The regulator is used to determine the gas mass flow rate at the current moment, the theoretical pressure of the gas collection pipe at the next moment, and the on / off combination of all sonic nozzles in the inlet and exhaust sonic valve groups based on preset gas mass flow rate trajectory data, the measured pressure in the gas collection pipe at the current moment, and the on / off combination data of all sonic nozzles in the inlet and exhaust sonic valve groups. It then drives the inlet sonic valve group, the exhaust sonic valve group, and the pressure regulating valve to perform the on / off operation of the sonic nozzles or pressure adjustment.

2. The gas mass flow rate follow-up control device according to claim 1, characterized in that, The type and number of sonic nozzles in the intake solenoid valve assembly are determined according to the required range of gas mass flow rate and the optimal upper and lower limits of the pressure regulating valve. The determination method includes the following steps: Assume the required gas mass flow rate range is: The unit is g / s, and the optimal working pressure range of the pressure regulating valve is... The unit is MPa, and the number of sonic nozzles. , No. i The diameter of each sonic nozzle is , i =1,2,…, n ; The diameter of the first sonic nozzle should be , q 1 represents the gas correlation coefficient, when air is used as the object of gas mass flow rate regulation. q 1 = 0.746; No. i The diameter of each sonic nozzle , For the first j The diameter of a sonic nozzle, j =1,2,…, i -1; The minimum number of sonic nozzles in the intake solenoid valve assembly is to satisfy The smallest inequality that holds true value, q 2 represents the gas correlation coefficient, when air is used as the object of gas mass flow rate regulation. q 2 = 1.

796.

3. The gas mass flow rate follow-up control device according to claim 1, characterized in that, The number of sonic nozzles and sonic valves in the intake sonic valve assembly and the exhaust sonic valve assembly are the same; and / or The sonic nozzles in the intake sonic valve group and the exhaust sonic valve group are installed on both sides of the air collection pipe, and the opposite sonic nozzles have the same diameter and their switching states are reversed.

4. The gas mass flow rate follow-up control device according to claim 1, characterized in that, The regulator includes an arithmetic and control module, an isolation module, and a drive module; The isolation module is used to receive the measured pressure signal in the gas collection pipe at the current moment and the on / off combination status data of each sonic nozzle, and transmit it to the calculation and control module after level conversion; The calculation and control module is used to determine the gas mass flow rate at the current moment based on the measured pressure signal in the gas collection pipe and the on / off combination status data of each sonic nozzle, and to determine the theoretical pressure of the gas collection pipe and the on / off combination of all sonic nozzles in the inlet sonic valve group and the exhaust sonic valve group at the next moment based on the preset gas mass flow trajectory data. The drive module is used to receive control commands sent by the calculation and control module, and distribute the control commands to the intake solenoid valve group, the exhaust solenoid valve group, and the pressure regulating valve.

5. The gas mass flow rate follow-up control device according to claim 4, characterized in that, The regulator also includes a human-machine interface, which serves as an input terminal to send preset gas mass flow trajectory data to the calculation and control module, and displays real-time gas mass flow data; and / or The regulator also includes a protection module, which, under the drive of the drive module, automatically disconnects the inlet valve or power supply of the gas mass flow follow-up control device when gas or electrical overload occurs in the upstream gas supply equipment, downstream gas consumption equipment, and gas mass flow follow-up control device.

6. The gas mass flow rate follow-up control device according to claim 4, characterized in that, The calculation and control module determines the current gas mass flow rate based on the measured pressure signal in the gas collecting pipe and the on / off combination status data of each sonic nozzle, and implements this in the following manner: (Note: The original text contains some formatting errors and inconsistencies. A more accurate translation would require the full context.) For the intake solenoid valve assembly, the sonic nozzle i The on / off state is indicated by 0, where 0 represents the solenoid valve of a certain solenoid nozzle is closed, and 1 represents the solenoid valve of a certain solenoid nozzle is open. The current gas mass flow rate is also indicated. ,in, q 2 represents the gas correlation coefficient, when air is used as the object of gas mass flow rate regulation. q 2 = 1.796; The number of sonic nozzles, For the first i The diameter of a sonic nozzle, i =1,2,…, n ; P 0. The measured pressure value inside the gas collection tube at the current moment.

7. The gas mass flow rate follow-up control device according to claim 4, characterized in that, The calculation and control module determines the next moment's gas collection system theoretical pressure and the on / off combinations of all sonic nozzles in the intake and exhaust sonic valve groups based on preset gas mass flow trajectory data, including: Based on all the switching items of each sonic nozzle in the intake solenoid valve assembly, record... For the intake solenoid valve assembly, the sonic nozzle i The on / off state is 0, indicating that the solenoid valve of a certain solenoid nozzle is closed, and 1, indicating that the solenoid valve of a certain solenoid nozzle is open, while simultaneously constructing... n The eigenvector of the +2D intake solenoid valve assembly sonic nozzle, the front of the eigenvector n The first item represents the on / off state of each sonic nozzle in the intake solenoid valve assembly, and the last two items represent the minimum and maximum gas mass flow rates for this combination. , ,…, ,…, , , ; q 2 represents the gas correlation coefficient, when air is used as the object of gas mass flow rate regulation. q 2 = 1.796; These represent the minimum and maximum working pressures of the pressure regulating valve, in MPa, and the number of sonic nozzles. , No. i The diameter of each sonic nozzle is , i =1,2,…, n ; The switching states of each sonic nozzle in the exhaust sonic valve assembly are reversed compared to the switching states of each sonic nozzle in the intake sonic valve assembly. Step 2, record k The gas mass flow rate that needs to be adjusted at all times is Iterate through the combinations of sonic nozzle on / off states, and satisfy the last two conditions. The front of the eigenvector n The term is used as the mass flow rate of the gas. The sonic nozzle switch status, and simultaneously determine the current state. ; q 3 represents the gas correlation coefficient, when air is used as the object of gas mass flow rate regulation. q 3 = 0.557; for k The pressure regulating valve needs to adjust the working pressure at all times; If satisfied When there are multiple sonic nozzle switch combinations, at the initial moment k =1 Select the combination number with the largest binary value during the voltage regulation phase. k ≥2 Select the combination with the fewest changes in the sonic nozzle state compared to the previous moment as the optimal solution for the current moment.

8. The gas mass flow rate follow-up control device according to claim 4, characterized in that, The isolation module uses an optocoupler to optically isolate the on / off combination status data of the sonic nozzle before communicating with the calculation and control module; the voltage and current acquisition module uses an isolation and conversion module to collect the pressure signal in the gas collection pipe before communicating with the calculation and control module.

9. The gas mass flow rate follow-up control device according to claim 4, characterized in that, The drive module controls the switching of the solenoid valves in the intake solenoid valve group and the exhaust solenoid valve group through a relay circuit, and sends the required pressure value to the pressure regulating valve through a D / A circuit.

10. A method for controlling the mass flow rate of a gas, characterized in that, Implemented by the gas mass flow rate follow-up control device according to any one of claims 1 to 9, the method includes the following steps: The type and number of sonic nozzles in the intake solenoid valve assembly are determined based on the required range of gas mass flow rate and the optimal upper and lower limits of the pressure regulating valve. The type and number of sonic nozzles in the exhaust sonic valve assembly are determined based on the type and number of sonic nozzles in the intake sonic valve assembly. Based on all the switching terms of each sonic nozzle in the intake sonic valve group, and the minimum and maximum values ​​of the gas mass flow rate corresponding to the combination of switching terms, construct the feature vector of the sonic nozzle in the intake sonic valve group. The gas mass flow rate at the current moment is determined based on the measured pressure signal in the gas collection pipe and the on / off combination status data of each sonic nozzle. The theoretical pressure of the gas collection pipe at the next moment and the on / off combination of all sonic nozzles in the inlet sonic valve group and the exhaust sonic valve group are determined based on the preset gas mass flow rate trajectory data and the characteristic vector of the sonic nozzles in the inlet sonic valve group. The inlet sonic valve group, the exhaust sonic valve group and the pressure regulating valve are then driven to perform the on / off operation of the sonic nozzles or pressure adjustment.

11. The gas mass flow rate follow-up control method according to claim 10, characterized in that, The step of constructing the feature vector of the sonic nozzles in the intake sonic valve assembly based on all the switching terms of each sonic nozzle in the intake sonic valve assembly, and the minimum and maximum values ​​of the gas mass flow rate corresponding to the combination of switching terms, includes: Based on all the switching items of each sonic nozzle in the intake solenoid valve assembly, record... For the intake solenoid valve assembly, the sonic nozzle i The on / off state is 0, indicating that the solenoid valve of a certain solenoid nozzle is closed, and 1 indicates that the solenoid valve of a certain solenoid nozzle is open. Construction n The eigenvector of the +2D intake solenoid valve assembly sonic nozzle, the front of the eigenvector n The first item represents the on / off state of each sonic nozzle in the intake solenoid valve assembly, and the last two items represent the minimum and maximum gas mass flow rates for this combination. , ,…, ,…, , , ; q 2 represents the gas correlation coefficient, when air is used as the object of gas mass flow rate regulation. q 2 = 1.796; These represent the minimum and maximum working pressures of the pressure regulating valve, in MPa, and the number of sonic nozzles. , No. i The diameter of each sonic nozzle is , i =1,2,…, n .

12. The gas mass flow rate follow-up control method according to claim 10, characterized in that, The step of determining the gas mass flow rate at the current moment based on the measured pressure signal in the gas collecting pipe and the on / off combination status data of each sonic nozzle includes: remember For the intake solenoid valve assembly, the sonic nozzle i The on / off state is indicated by 0, where 0 represents the solenoid valve of a certain solenoid nozzle is closed, and 1 represents the solenoid valve of a certain solenoid nozzle is open. The current gas mass flow rate is also indicated. ,in, q 2 represents the gas correlation coefficient, when air is used as the object of gas mass flow rate regulation. q 2 = 1.796; The number of sonic nozzles, For the first i The diameter of a sonic nozzle, i =1,2,…, n ; P 0. The measured pressure value inside the gas collection tube at the current moment.

13. The gas mass flow rate follow-up control method according to claim 10, characterized in that, The steps of determining the next moment's theoretical pressure of the gas collection system and the switching combinations of all sonic nozzles in the intake and exhaust sonic valve groups based on preset gas mass flow trajectory data and the characteristic vectors of the sonic nozzles in the intake sonic valve group include: remember k The gas mass flow rate that needs to be adjusted at all times is Iterate through the combinations of sonic nozzle on / off states, and satisfy the last two conditions. The front of the eigenvector n The term is used as the mass flow rate of the gas. The sonic nozzle switch status, and simultaneously determine the current state. ; q 3 represents the gas correlation coefficient, when air is used as the object of gas mass flow rate regulation. q 3 = 0.557; These represent the minimum and maximum working pressures of the pressure regulating valve, in MPa, and the number of sonic nozzles. , No. i The diameter of each sonic nozzle is , i =1,2,…, n ; for k The pressure regulating valve needs to adjust the working pressure at all times; If satisfied When there are multiple sonic nozzle switch combinations, at the initial moment k =1 Select the combination number with the largest binary value during the voltage regulation phase. k ≥2 Select the combination with the fewest changes in the sonic nozzle state compared to the previous moment as the optimal solution for the current moment.

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