Propellant replenishment system testing method and system based on state machine

Abstract

The present invention provides a state machine-based propellant replenishing system testing method and system, including: a gas cylinder module: including a gas cylinder, a transverse valve, a longitudinal valve and a pressure sensor; a compressor module: including a compressor, inlet and outlet pipelines and valves; a tank module: including a tank, a tank outlet valve, a tank inlet valve, a pressure sensor, a displacement sensor; a liquid pipeline module: including an interface, related valves and pipelines. 1. The present invention provides a propellant replenishing system model, which is used to construct a digital prototype or a semi-physical prototype of a propellant replenishing system to verify the algorithms and programs of the replenishing system control system; it can replace the physical model of the propellant replenishing system, directly construct a virtual verification system for the algorithms and programs of the replenishing control system, and can also be combined with a physical system to form a semi-physical replenishing system simulation verification system to achieve rapid verification of the algorithms and programs of the propulsion replenishing control system.

Description

Technical Field

[0001] The present invention relates to the field of digital models of replenishing systems, and in particular to a propellant replenishing method and system based on a state machine. Background Art

[0002] As a key technology for the long-life operation of on-orbit spacecraft, on-orbit propellant replenishment technology has been used in space stations and some satellites and other spacecraft propulsion systems at home and abroad. my country's Tianzhou-1 cargo spacecraft and Tiangong-2 space laboratory completed the first on-orbit propellant replenishment test in April 2017 (Military and Civilian Dual-Use Technology and Products 2017 No. 385 Vol. 11 2017-06-15), marking that my country has made a breakthrough in propellant replenishment technology. The control of the replenishment process is the key link in realizing propellant replenishment. The algorithm and program of the replenishment control system must be fully tested and tested to verify its correctness and effectiveness before actual application. The previous method generally used a real propellant replenishment system or a simulator as a test prototype to complete the verification of the replenishment control system.

[0003] Patent document CN108146663B (application number: CN201711283762.7) discloses a spacecraft propellant replenishment simulation test system, including: a replenishing simulation device and a replenished simulation device; wherein: the replenishing simulation device is composed of a replenishing simulation main controller, a replenishing simulation data controller, a replenishing simulation measurement and control device, and a replenishing simulation starter; the replenished simulation device is composed of a replenished simulation main controller, a replenished simulation data controller, a replenished simulation measurement and control device, and a replenished simulation starter; the replenishing simulation device and the replenished simulation device are connected to each other through a network so as to exchange information, and exchange simulated fault information with each other during the propellant replenishment simulation test.

[0004] Patent document CN111075607A (application number: CN201911284087.9) discloses a test system and method for the autonomous space propellant replenishment process, which uses a space propellant replenishment model to simulate the actual space propellant replenishment system and verify the correctness of the space propellant autonomous replenishment process and fault handling method. The space propellant replenishment system actuator simulator simulates various actuators, and the replenishment model collects the operating status of the space replenishment actuator, which is then converted into various sensor signals required for replenishment and output to the ground test module. The ground test module converts and processes the sensor signals to generate instructions to control replenishment measurement and control.

[0005] However, the supplementary system test prototypes of the above two inventions based on the physical system not only require a lot of research and development funds, but also have a long development cycle, high maintenance costs, and are difficult to inherit and transplant, which has great limitations.

[0006] Patent document CN108595155A (application number: CN201810351936.7) discloses a propellant quantitative replenishment system and its implementation method during the liquid rocket engine test process, which belongs to the field of computer software and is used to solve the problem of propellant filling accuracy during the liquid rocket engine test process. The liquid rocket engine test propellant filling process is studied, and a kerosene quantitative replenishment system is redesigned and established on the original filling system. This software adopts the design scheme of field instrument + acquisition system + relay card. In order to improve the timing accuracy, this software uses the multimedia timer STimer industrial control as the timer. In order to improve data reliability, the analog + digital filtering method is used to filter the data. However, this invention cannot quickly verify the changes in the replenishment system requirements, and cannot quickly build test prototypes of different replenishment systems. Summary of the invention

[0007] In view of the defects in the prior art, an object of the present invention is to provide a propellant replenishing system testing method and system based on a state machine.

[0008] A propellant replenishing system test system based on a state machine provided by the present invention comprises:

[0009] Gas cylinder module: includes gas cylinder, transverse valve, longitudinal valve and pressure sensor. The pressure sensor is located at the outlet of the gas cylinder and indicates the pressure of the gas cylinder. The transverse valve is connected to the pressurization system, and the longitudinal valve is connected to the storage tank.

[0010] Compressor module: includes compressor, inlet and outlet pipelines and valves. The compressor outlet pipeline is connected to the gas cylinder, and the compressor inlet pipeline is connected to the tank. The valve is a compressor pressure relief valve.

[0011] Tank module: includes a tank, a tank outlet valve, a tank inlet valve, a pressure sensor, and a displacement sensor. The pressure sensor is located at the tank inlet and indicates the tank pressure; the displacement sensor is located inside the tank and indicates the volume of the tank propellant; the tank inlet valve is connected to the compressor module, and the tank inlet pipeline is connected to the gas cylinder; the tank outlet valve and pipeline are connected to the liquid pipeline;

[0012] Liquid pipeline module: includes interfaces, related valves and pipelines. The replenishing interface is the propellant input interface, and the output interface is connected to the tank; the blow-off interface is the outlet for propellant blow-off. The replenishing interface, output interface and blow-off interface are isolated by valves respectively.

[0013] Preferably, an empirical formula is used to describe the changes in attribute parameters during the state transition process:

[0014] P=P0+Pd*t

[0015] P is pressure, P0 is the pressure in the previous state, Pd is the pressure change coefficient, and t is time;

[0016] The input parameters of state transition, except attribute parameters, are generated by control algorithms and programs to verify control algorithms and programs;

[0017] Each functional module is abstracted and encapsulated, the internal behavior of the module is described by a state machine, and interface parameters are used to couple the modules and between the modules and the replenishment control system, thus forming a propellant replenishment system test model.

[0018] Preferably, in the gas cylinder module:

[0019] The valve switch command generated by the control algorithm is used as an input parameter to trigger the state transition;

[0020] Extract test-related pressure and valve switch status as cylinder attributes;

[0021] The attribute represents the state of the module and is fed back to the supplementary control system as an output signal;

[0022] The valve switch command is issued by the replenishment control system. After receiving the command, the gas cylinder module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete the program algorithm verification.

[0023] A state machine is used to describe the behavior of the gas cylinder during the refueling process; state 1 is the initial state of the gas cylinder, state 2 is the state of the compressor pressurizing the gas cylinder, state 3 is the high-pressure state of the gas cylinder, state 4 is the state of the gas cylinder pressurizing the tank, and state 5 is the low-pressure state of the gas cylinder; different states and transitions represent the operations that the gas cylinder needs to perform at different stages of the refueling process and the responses after the operations. A state machine is used to describe the behavior of the gas cylinder during the refueling process;

[0024] State transitions are triggered by input parameters;

[0025] The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program algorithm.

[0026] In the compressor module:

[0027] Use the cooling on / off command, valve on / off command, compressor start / stop command as input parameters to trigger state transition;

[0028] Extract the compressor inlet and outlet pressures and temperatures and valve switch status as compressor attributes;

[0029] The cooling on / off command, valve on / off command, compressor start / shutdown command are issued by the supplementary control system. After receiving the command, the compressor module simulates the corresponding changes in the property parameters of the physical system and feeds back to the supplementary control system. The supplementary control system uses the feedback signal to complete the program algorithm verification.

[0030] The state machine is used to describe the compressor behavior during the charging process: state 1 is the initial state of the compressor, state 2 is the compressor cooling state, state 3 is the cooling stop state, state 4 is the switch compressor operation state; state 5 is the compressor shutdown state; state 6 is the compressor pressure relief state; state 7 is the pressure relief end state,

[0031] State transitions are triggered by input parameters;

[0032] The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program and algorithm.

[0033] Preferably, in the tank module:

[0034] The valve switch command is used as an input parameter to trigger the state transition;

[0035] Extracting tank pressure, remaining volume and valve switch status as tank attributes;

[0036] The valve switch command is issued by the replenishment control system. After receiving the command, the tank module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete the program algorithm verification.

[0037] The state machine is used to describe the behavior of the tank module during the replenishment process: state 1 is the initial state of the tank, state 2 is the state of the tank supplying air to the compressor, state 3 is the state of the compressor pumping air from the tank, state 4 is the low-pressure state of the tank, state 5 is the propellant replenishment flow state, state 6 is the propellant replenishment in place state; state 7 is the tank pressurization state; state 8 is the tank pressurization end state;

[0038] State transitions are triggered by input parameters;

[0039] The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program algorithm.

[0040] Preferably, in the liquid pipeline module:

[0041] The valve switch command is used as an input parameter to trigger the state transition;

[0042] Extract the replenishment pipeline pressure and valve switch status as the replenishment pipeline module attributes;

[0043] The input parameter is the valve switch command;

[0044] The valve switch command is issued by the replenishment control system. After receiving the command, the liquid pipeline module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete the program algorithm verification.

[0045] The state machine is used to describe the behavior of the liquid pipeline module during the replenishment process: state 1 is the initial state of the liquid pipeline module, state 2 is the state after the propellant pipeline is pressurized, state 3 is the propellant replenishment flow state, state 4 is the propellant replenishment completion state, state 5 is the propellant blow-off state, and state 6 is the blow-off end state;

[0046] State transitions are triggered by input parameters;

[0047] The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program algorithm.

[0048] According to a state machine-based propellant replenishment system test method provided by the present invention, the propellant replenishment system test system based on the state machine is used to perform the following steps:

[0049] Step S1: The gas cylinder module, the gas compressor module, the storage tank module and the liquid pipeline module receive relevant instructions from the replenishment control system;

[0050] Step S2: Simulate the state change of the physical system and output the attribute parameters for feedback transmission to the supplementary control system;

[0051] Step S3: The additional control system automatically determines whether the algorithm and program for module operation are correct through the feedback signal. Preferably, an empirical formula is used to describe the attribute parameter changes in the state conversion process:

[0052] P=P0+Pd*t

[0053] P is pressure, P0 is the pressure in the previous state, Pd is the pressure change coefficient, and t is time;

[0054] The input parameters of state transition, except for attribute parameters, are generated by control algorithms and programs to verify the control algorithms and programs.

[0055] Preferably, in the gas cylinder module:

[0056] The valve switch command generated by the control algorithm is used as an input parameter to trigger the state transition;

[0057] Extract test-related pressure and valve switch status as cylinder attributes;

[0058] The attribute represents the state of the module and is fed back to the supplementary control system as an output signal;

[0059] The valve switch command is issued by the replenishment control system. After receiving the command, the gas cylinder module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete the program algorithm verification.

[0060] A state machine is used to describe the behavior of the gas cylinder during the refueling process; state 1 is the initial state of the gas cylinder, state 2 is the state of the compressor pressurizing the gas cylinder, state 3 is the high-pressure state of the gas cylinder, state 4 is the state of the gas cylinder pressurizing the tank, and state 5 is the low-pressure state of the gas cylinder; different states and transitions represent the operations that the gas cylinder needs to perform at different stages of the refueling process and the responses after the operations. A state machine is used to describe the behavior of the gas cylinder during the refueling process;

[0061] State transitions are triggered by input parameters;

[0062] The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program algorithm.

[0063] In the compressor module:

[0064] Use the cooling on / off command, valve on / off command, compressor start / stop command as input parameters to trigger state transition;

[0065] Extract the compressor inlet and outlet pressures and temperatures and valve switch status as compressor attributes;

[0066] The cooling on / off command, valve on / off command, compressor start / shutdown command are issued by the supplementary control system. After receiving the command, the compressor module simulates the corresponding changes in the property parameters of the physical system and feeds back to the supplementary control system. The supplementary control system uses the feedback signal to complete the program algorithm verification.

[0067] The state machine is used to describe the compressor behavior during the charging process: state 1 is the initial state of the compressor, state 2 is the compressor cooling state, state 3 is the cooling stop state, state 4 is the switch compressor operation state; state 5 is the compressor shutdown state; state 6 is the compressor pressure relief state; state 7 is the pressure relief end state,

[0068] State transitions are triggered by input parameters;

[0069] The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program and algorithm.

[0070] Preferably, in the tank module:

[0071] The valve switch command is used as an input parameter to trigger the state transition;

[0072] Extracting tank pressure, remaining volume and valve switch status as tank attributes;

[0073] The valve switch command is issued by the replenishment control system. After receiving the command, the tank module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete the program algorithm verification.

[0074] The state machine is used to describe the behavior of the tank module during the replenishment process: state 1 is the initial state of the tank, state 2 is the state of the tank supplying air to the compressor, state 3 is the state of the compressor pumping air from the tank, state 4 is the low-pressure state of the tank, state 5 is the propellant replenishment flow state, state 6 is the propellant replenishment in place state; state 7 is the tank pressurization state; state 8 is the tank pressurization end state;

[0075] State transitions are triggered by input parameters;

[0076] The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program algorithm.

[0077] Preferably, in the liquid pipeline module:

[0078] The valve switch command is used as an input parameter to trigger the state transition;

[0079] Extract the replenishment pipeline pressure and valve switch status as the replenishment pipeline module attributes;

[0080] The input parameter is the valve switch command;

[0081] The valve switch command is issued by the replenishment control system. After receiving the command, the liquid pipeline module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete the program algorithm verification.

[0082] The state machine is used to describe the behavior of the liquid pipeline module during the replenishment process: state 1 is the initial state of the liquid pipeline module, state 2 is the state after the propellant pipeline is pressurized, state 3 is the propellant replenishment flow state, state 4 is the propellant replenishment completion state, state 5 is the propellant blow-off state, and state 6 is the blow-off end state;

[0083] State transitions are triggered by input parameters;

[0084] The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program algorithm.

[0085] Compared with the prior art, the present invention has the following beneficial effects:

[0086] 1. The present invention provides a propellant replenishment system model, which is used to construct a digital prototype or a semi-physical prototype of the propellant replenishment system, and to verify the algorithm and program of the replenishment system control system;

[0087] 2. The present invention can replace the physical model of the propellant replenishment system and directly construct a virtual verification system for the replenishment control system algorithm and program. It can also be combined with the physical system to form a semi-physical replenishment system simulation verification system to achieve rapid verification of the propulsion replenishment control system algorithm and program;

[0088] 3. The present invention can construct a digital prototype for supplementary system testing, avoiding the development of a physical test prototype system and saving a large amount of research and development funds;

[0089] 4. The digital prototype or semi-physical prototype of the supplementary system test constructed by the present invention can complete the rapid verification of the supplementary process control algorithm, program, etc., and improve the research and development efficiency of the supplementary control system;

[0090] 5. The supplementary system model provided by the present invention is easy to expand and transplant, and is very suitable for rapid verification of changes in supplementary system requirements, and is also suitable for rapid construction of different supplementary system test prototypes. BRIEF DESCRIPTION OF THE DRAWINGS

[0091] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0092] Figure 1 It is a propellant replenishment system model;

[0093] Figure 2 This is a simplified diagram of the propellant replenishment system and the replenishment control system;

[0094] Figure 3 It is the state transition diagram of the gas cylinder module;

[0095] Figure 4 It is the state transition diagram of the compressor module;

[0096] Figure 5 It is the state transition diagram of the tank module;

[0097] Figure 6 This is the state transfer diagram of the liquid pipeline. DETAILED DESCRIPTION

[0098] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0099] Embodiment 1:

[0100] According to a propellant replenishment system test system based on a state machine provided by the present invention, Figure 1-Figure 6 As shown, including:

[0101] Gas cylinder module: includes gas cylinder, transverse valve, longitudinal valve and pressure sensor. The pressure sensor is located at the outlet of the gas cylinder and indicates the pressure of the gas cylinder. The transverse valve is connected to the pressurization system, and the longitudinal valve is connected to the storage tank.

[0102] Compressor module: includes compressor, inlet and outlet pipelines and valves. The compressor outlet pipeline is connected to the gas cylinder, and the compressor inlet pipeline is connected to the tank. The valve is a compressor pressure relief valve.

[0103] Tank module: includes a tank, a tank outlet valve, a tank inlet valve, a pressure sensor, and a displacement sensor. The pressure sensor is located at the tank inlet and indicates the tank pressure; the displacement sensor is located inside the tank and indicates the volume of the tank propellant; the tank inlet valve is connected to the compressor module, and the tank inlet pipeline is connected to the gas cylinder; the tank outlet valve and pipeline are connected to the liquid pipeline;

[0104] Liquid pipeline module: includes interfaces, related valves and pipelines. The replenishing interface is the propellant input interface, and the output interface is connected to the tank; the blow-off interface is the outlet for propellant blow-off. The replenishing interface, output interface and blow-off interface are isolated by valves respectively.

[0105] Specifically, an empirical formula is used to describe the changes in attribute parameters during the state transition process:

[0106] P=P0+Pd*t

[0107] P is pressure, P0 is the pressure in the previous state, Pd is the pressure change coefficient, and t is time;

[0108] The input parameters of state transition, except attribute parameters, are generated by control algorithms and programs to verify control algorithms and programs;

[0109] Each functional module is abstracted and encapsulated, the internal behavior of the module is described by a state machine, and interface parameters are used to couple the modules and between the modules and the replenishment control system, thus forming a propellant replenishment system test model.

[0110] Specifically, in the gas cylinder module:

[0111] The valve switch command generated by the control algorithm is used as an input parameter to trigger the state transition;

[0112] Extract test-related pressure and valve switch status as cylinder attributes;

[0113] The attribute represents the state of the module and is fed back to the supplementary control system as an output signal;

[0114] The valve switch command is issued by the replenishment control system. After receiving the command, the gas cylinder module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete the program algorithm verification.

[0115] A state machine is used to describe the behavior of the gas cylinder during the refueling process; state 1 is the initial state of the gas cylinder, state 2 is the state of the compressor pressurizing the gas cylinder, state 3 is the high-pressure state of the gas cylinder, state 4 is the state of the gas cylinder pressurizing the tank, and state 5 is the low-pressure state of the gas cylinder; different states and transitions represent the operations that the gas cylinder needs to perform at different stages of the refueling process and the responses after the operations. A state machine is used to describe the behavior of the gas cylinder during the refueling process;

[0116] State transitions are triggered by input parameters;

[0117] The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program algorithm.

[0118] In the compressor module:

[0119] Use the cooling on / off command, valve on / off command, compressor start / stop command as input parameters to trigger state transition;

[0120] Extract the compressor inlet and outlet pressures and temperatures and valve switch status as compressor attributes;

[0121] The cooling on / off command, valve on / off command, compressor start / shutdown command are issued by the supplementary control system. After receiving the command, the compressor module simulates the corresponding changes in the property parameters of the physical system and feeds back to the supplementary control system. The supplementary control system uses the feedback signal to complete the program algorithm verification.

[0122] The state machine is used to describe the compressor behavior during the charging process: state 1 is the initial state of the compressor, state 2 is the compressor cooling state, state 3 is the cooling stop state, state 4 is the switch compressor operation state; state 5 is the compressor shutdown state; state 6 is the compressor pressure relief state; state 7 is the pressure relief end state,

[0123] State transitions are triggered by input parameters;

[0124] The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program and algorithm.

[0125] Specifically, in the tank module:

[0126] The valve switch command is used as an input parameter to trigger the state transition;

[0127] Extracting tank pressure, remaining volume and valve switch status as tank attributes;

[0128] The valve switch command is issued by the replenishment control system. After receiving the command, the tank module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete the program algorithm verification.

[0129] The state machine is used to describe the behavior of the tank module during the replenishment process: state 1 is the initial state of the tank, state 2 is the state of the tank supplying air to the compressor, state 3 is the state of the compressor pumping air from the tank, state 4 is the low-pressure state of the tank, state 5 is the propellant replenishment flow state, state 6 is the propellant replenishment in place state; state 7 is the tank pressurization state; state 8 is the tank pressurization end state;

[0130] State transitions are triggered by input parameters;

[0131] The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program algorithm.

[0132] Specifically, in the liquid pipeline module:

[0133] The valve switch command is used as an input parameter to trigger the state transition;

[0134] Extract the replenishment pipeline pressure and valve switch status as the replenishment pipeline module attributes;

[0135] The input parameter is the valve switch command;

[0136] The valve switch command is issued by the replenishment control system. After receiving the command, the liquid pipeline module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete the program algorithm verification.

[0137] The state machine is used to describe the behavior of the liquid pipeline module during the replenishment process: state 1 is the initial state of the liquid pipeline module, state 2 is the state after the propellant pipeline is pressurized, state 3 is the propellant replenishment flow state, state 4 is the propellant replenishment completion state, state 5 is the propellant blow-off state, and state 6 is the blow-off end state;

[0138] State transitions are triggered by input parameters;

[0139] The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program algorithm.

[0140] Embodiment 2:

[0141] Embodiment 2 is a preferred example of Embodiment 1, and is used to illustrate the present invention in more detail.

[0142] A person skilled in the art may understand the state machine-based propellant replenishing system testing method provided by the present invention as a specific implementation of a state machine-based propellant replenishing system testing system, that is, the state machine-based propellant replenishing system testing system may be implemented by executing the step flow of the state machine-based propellant replenishing system testing method.

[0143] A propellant replenishment system testing method based on a state machine provided by the present invention includes:

[0144] Step S1: The gas cylinder module, the gas compressor module, the storage tank module and the liquid pipeline module receive relevant instructions from the replenishment control system;

[0145] Step S2: Simulate the state change of the physical system and output the attribute parameters for feedback transmission to the supplementary control system;

[0146] Step S3: The additional control system automatically determines whether the algorithm and program for module operation are correct through the feedback signal. Specifically, an empirical formula is used to describe the attribute parameter changes in the state conversion process:

[0147] P=P0+Pd*t

[0148] P is pressure, P0 is the pressure in the previous state, Pd is the pressure change coefficient, and t is time;

[0149] The input parameters of state transition, except for attribute parameters, are generated by control algorithms and programs to verify the control algorithms and programs.

[0150] Specifically, in the gas cylinder module:

[0151] The valve switch command generated by the control algorithm is used as an input parameter to trigger the state transition;

[0152] Extract test-related pressure and valve switch status as cylinder attributes;

[0153] The attribute represents the state of the module and is fed back to the supplementary control system as an output signal;

[0154] The valve switch command is issued by the replenishment control system. After receiving the command, the gas cylinder module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete the program algorithm verification.

[0155] A state machine is used to describe the behavior of the gas cylinder during the refueling process; state 1 is the initial state of the gas cylinder, state 2 is the state of the compressor pressurizing the gas cylinder, state 3 is the high-pressure state of the gas cylinder, state 4 is the state of the gas cylinder pressurizing the tank, and state 5 is the low-pressure state of the gas cylinder; different states and transitions represent the operations that the gas cylinder needs to perform at different stages of the refueling process and the responses after the operations. A state machine is used to describe the behavior of the gas cylinder during the refueling process;

[0156] State transitions are triggered by input parameters;

[0157] The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program algorithm.

[0158] In the compressor module:

[0159] Use the cooling on / off command, valve on / off command, compressor start / stop command as input parameters to trigger state transition;

[0160] Extract the compressor inlet and outlet pressures and temperatures and valve switch status as compressor attributes;

[0161] The cooling on / off command, valve on / off command, compressor start / shutdown command are issued by the supplementary control system. After receiving the command, the compressor module simulates the corresponding changes in the property parameters of the physical system and feeds back to the supplementary control system. The supplementary control system uses the feedback signal to complete the program algorithm verification.

[0162] The state machine is used to describe the compressor behavior during the charging process: state 1 is the initial state of the compressor, state 2 is the compressor cooling state, state 3 is the cooling stop state, state 4 is the switch compressor operation state; state 5 is the compressor shutdown state; state 6 is the compressor pressure relief state; state 7 is the pressure relief end state,

[0163] State transitions are triggered by input parameters;

[0164] The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program and algorithm.

[0165] Specifically, in the tank module:

[0166] The valve switch command is used as an input parameter to trigger the state transition;

[0167] Extracting tank pressure, remaining volume and valve switch status as tank attributes;

[0168] The valve switch command is issued by the replenishment control system. After receiving the command, the tank module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete the program algorithm verification.

[0169] The state machine is used to describe the behavior of the tank module during the replenishment process: state 1 is the initial state of the tank, state 2 is the state of the tank supplying air to the compressor, state 3 is the state of the compressor pumping air from the tank, state 4 is the low-pressure state of the tank, state 5 is the propellant replenishment flow state, state 6 is the propellant replenishment in place state; state 7 is the tank pressurization state; state 8 is the tank pressurization end state;

[0170] State transitions are triggered by input parameters;

[0171] The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program algorithm.

[0172] Specifically, in the liquid pipeline module:

[0173] The valve switch command is used as an input parameter to trigger the state transition;

[0174] Extract the replenishment pipeline pressure and valve switch status as the replenishment pipeline module attributes;

[0175] The input parameter is the valve switch command;

[0176] The valve switch command is issued by the replenishment control system. After receiving the command, the liquid pipeline module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete the program algorithm verification.

[0177] The state machine is used to describe the behavior of the liquid pipeline module during the replenishment process: state 1 is the initial state of the liquid pipeline module, state 2 is the state after the propellant pipeline is pressurized, state 3 is the propellant replenishment flow state, state 4 is the propellant replenishment completion state, state 5 is the propellant blow-off state, and state 6 is the blow-off end state;

[0178] State transitions are triggered by input parameters;

[0179] The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program algorithm.

[0180] Embodiment 3:

[0181] Embodiment 3 is a preferred example of Embodiment 1, and is used to illustrate the present invention in more detail.

[0182] The present invention provides a test model for a spacecraft propellant replenishing system based on a state machine. The basic modules and properties of the replenishing system related to the test requirements are abstracted by an object-oriented method, the internal behavior of the basic modules of the replenishing system is described by a state machine and an empirical formula, and the state machine conversion is triggered by a control program output instruction. The model of the present invention can be used to construct a digital prototype or a semi-physical prototype of the propellant replenishing system, and the replenishing control system can be applied to the replenishing model to complete the verification of the replenishing control algorithm and program.

[0183] The digital prototype or semi-physical prototype constructed by adopting the model of the present invention is easy to modify and change, has strong adaptability, and takes a short construction time, and can realize rapid verification of the propellant replenishment control algorithm and the control program.

[0184] The present invention uses a finite state machine to simulate the behavior of the propellant replenishing system during the propellant replenishing process. Different states are described by changes in its attribute parameters, which are output signals of the propellant replenishing system. State transitions are triggered by input parameters of the replenishing control system, so that the model simulates the response of the propellant replenishing system after receiving the input parameters of the replenishing control system, and outputs them as feedback signals. The replenishing control system can use the feedback signals to complete the verification of its program and algorithm.

[0185] 1. The model is characterized by being applicable to Figure 2 The replenishment system with pressurized gas recycling is shown. Figure 2 The propellant replenishment process is that the replenishment control system issues instructions to drive the replenishment system to operate and generate feedback signals. The correctness of the replenishment control system algorithm and program is judged by the feedback signal.

[0186] The model of the present invention divides the propellant replenishing system into four basic modules: a gas cylinder module (2), a compressor module (3), a tank module (4), and a liquid pipeline module (5). For each module, an object-oriented method is used to extract only the attribute parameters required for verifying the replenishing control system algorithm and the program for digital simulation. Figure 1 Yes Figure 2 Abstraction of the propellant replenishment system. The behavior of the propellant replenishment process is described by the state machine of the four modules of the model of the present invention. The state change is triggered by the input command of the replenishment control system, and the state change is described by the change of attribute parameters. The attribute parameters are output signals and fed back to the replenishment control system. The specific method is as follows:

[0187] (1) When the model of the gas cylinder module receives relevant instructions from the replenishment control system, the gas cylinder module simulates the state change of the physical system and outputs attribute parameters for feedback to the replenishment control system. The replenishment control system automatically determines whether the algorithm and program for operating the gas cylinder module are correct through the feedback signal;

[0188] (2) When the compressor module receives the relevant command from the supplementary control system, the state of the compressor module changes accordingly, and the output attribute parameters are transmitted to the supplementary control system as feedback signals. The supplementary control system automatically determines whether the algorithm and program for operating the compressor module are correct through the feedback signals;

[0189] (3) When the tank module receives the relevant instructions from the replenishment control system, the state of the tank module changes accordingly, and the output attribute parameters are transmitted to the replenishment control system as feedback signals. The replenishment control system automatically determines whether the algorithm and program for operating the tank module are correct through the feedback signals;

[0190] (4) When the liquid pipeline module receives relevant instructions from the replenishment control system, the state of the liquid pipeline block box module changes accordingly, and the output attribute parameters are transmitted to the replenishment control system as feedback signals. The replenishment control system automatically determines whether the algorithm and program for operating the liquid pipeline module are correct through the feedback signals.

[0191] The state machines of the four modules of the model of the present invention can describe the entire propellant replenishing process, and a digital prototype of the replenishing system can be constructed. The replenishing control system verifies its algorithm and program by operating the model.

[0192] 2. The gas cylinder model (2) is characterized by:

[0193] 1) Encapsulate the gas cylinder body and the valves that control the connection of its horizontal and vertical pipelines in one module; 2) Extract the test-related pressure (P) and valve switch status (ON, OFF) as gas cylinder attributes;

[0194] The attribute represents the state of the module and is fed back to the supplementary control system as an output signal;

[0195] 3) The input parameters are the switch instructions of valves L1 and L2;

[0196] 4) If Figure 2 The valve switch command is issued by the replenishment control system. After receiving the command, the gas cylinder module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete its program and algorithm verification;

[0197] 5) Use a state machine to describe the behavior of the gas cylinder during the refueling process; state 1 is the initial state of the gas cylinder, state 2 is the state of the compressor pressurizing the gas cylinder, state 3 is the high-pressure state of the gas cylinder, state 4 is the state of the gas cylinder pressurizing the tank, and state 5 is the low-pressure state of the gas cylinder; different states and their transitions represent the operations that the gas cylinder needs to perform at different stages of the refueling process and the responses after the operations. That is, "use a state machine to describe the behavior of the gas cylinder during the refueling process."

[0198] 6) State transitions are triggered by input parameters;

[0199] 7) Attribute parameters, i.e., output signals, describe the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program and algorithm.

[0200] 3. The compressor module (3) is characterized by:

[0201] 1) Encapsulate the compressor body and its inlet and outlet pipelines and valves in one module;

[0202] 2) Extract the compressor inlet and outlet pressure (P), temperature (T), and valve switch status (ON, OFF) as compressor attributes;

[0203] 3) Input parameters include cooling on / off command, valve on / off command, compressor start / stop command;

[0204] 4) If Figure 2 The cooling on / off command, valve on / off command, compressor start-up command and shutdown command are all issued by the supplementary control system. After receiving the command, the compressor module simulates the corresponding changes in the property parameters of the physical system and feeds back to the supplementary control system; the supplementary control system uses the feedback signal to complete its program and algorithm verification

[0205] 5) The state machine is used to describe the compressor behavior during the charging process: state 1 is the initial state of the compressor, state 2 is the compressor cooling state, state 3 is the cooling stop state, state 4 is the switch compressor operation state; state 5 is the compressor shutdown state; state 6 is the compressor pressure relief state; state 7 is the pressure relief end state,

[0206] 6) State transitions are triggered by input parameters;

[0207] 7) Attribute parameters, i.e., output signals, describe the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program and algorithm.

[0208] The tank module (4) is characterized in that:

[0209] 1) Encapsulate the tank body, tank outlet and inlet valves, etc. in one module;

[0210] 2) Extracting tank pressure (P), remaining volume (H), and valve switch status (ON, OFF) as tank attributes;

[0211] 3) The input parameter is the valve switch instruction;

[0212] 4) If Figure 2 The valve switch command is issued by the replenishment control system. After receiving the command, the tank module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete its program and algorithm verification.

[0213] 5) The state machine is used to describe the behavior of the tank module during the replenishment process: state 1 is the initial state of the tank, state 2 is the state of the tank supplying air to the compressor, state 3 is the state of the compressor evacuating air from the tank, state 4 is the low-pressure state of the tank, state 5 is the propellant replenishment flow state, state 6 is the propellant replenishment in place state; state 7 is the tank pressurization state; state 8 is the tank pressurization end state;

[0214] 6) State transitions are triggered by input parameters;

[0215] 7) Attribute parameters, i.e., output signals, describe the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program and algorithm.

[0216] 4. The liquid pipeline module (5) is characterized by:

[0217] 1) Encapsulate the replenishing interface, the blow-off port, and the related valves and pipelines into one module;

[0218] 2) Extract the replenishment pipeline pressure and valve switch status as the replenishment pipeline module attributes;

[0219] 3) The input parameter is the valve switch instruction;

[0220] 4) If Figure 2 The valve switch command is issued by the replenishment control system. After receiving the command, the liquid pipeline module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete its program and algorithm verification.

[0221] 5) The state machine is used to describe the behavior of the liquid pipeline module during the replenishment process: state 1 is the initial state of the liquid pipeline module, state 2 is the state after the propellant pipeline is pressurized, state 3 is the propellant replenishment flow state, state 4 is the propellant replenishment completion state, state 5 is the propellant blow-off state, and state 6 is the blow-off end state;

[0222] 6) State transitions are triggered by input parameters;

[0223] 7) Attribute parameters, i.e., output signals, describe the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program and algorithm.

[0224] 5. Use empirical formulas to describe the changes in attribute parameters during the state transition process:

[0225] Pressure P=P0+Pd t; P0 is the pressure in the previous state, Pd is the pressure change coefficient, and t is time.

[0226] 6. The input parameters of the state transition of each module involved are also characterized in that, except for the attribute parameters, the remaining parameters are generated by the control algorithm and the program, thereby realizing the verification of the control algorithm and the program.

[0227] Embodiment 4:

[0228] Embodiment 4 is a preferred example of Embodiment 1, and is used to illustrate the present invention in more detail.

[0229] In view of the current situation in which the verification of replenishment control algorithms and programs in the development process of propellant replenishment systems is based on physical systems, the present invention proposes a propellant replenishment system model based on a state machine, which is used to build a digital test prototype or a semi-physical prototype of the replenishment system to achieve rapid verification of the propellant replenishment control algorithm and control program.

[0230] 1. The model described in the present invention is characterized in that the propellant replenishing system is abstracted into four basic modules: a gas cylinder module (2), a compressor module (3), a tank module (4), and a liquid pipeline module (5).

[0231] 2. The gas cylinder module of the present invention is characterized in that the gas cylinder, the transverse valve, the longitudinal valve (4) and the pressure sensor are encapsulated in one module, the transverse valve is connected to the boosting system of the replenishing system (compressor outlet), and the longitudinal valve is generally connected to the low-pressure gas circuit (storage tank).

[0232] 3. The gas cylinder module is also characterized in that the gas cylinder pressure (P) and the switch status of the transverse valve (3) and the longitudinal valve (4) are used as attribute parameters of the module.

[0233] 4. The gas cylinder module is also characterized by the state machine of the gas cylinder model; state 1 is the initial state of the gas cylinder, state 2 is the state of the compressor pressurizing the gas cylinder, state 3 is the high-pressure state of the gas cylinder, state 4 is the state of the gas cylinder pressurizing the storage tank, and state 5 is the low-pressure state of the gas cylinder.

[0234] 5. The gas cylinder module is also characterized in that the state machine state transition of the gas cylinder model is triggered by input parameters, and the input parameters are valve switch instructions generated by the control algorithm and the program.

[0235] 6. The compressor module is characterized in that the compressor body and its inlet and outlet pipelines and valves are encapsulated in one module.

[0236] 7. The compressor module is also characterized in that the compressor inlet and outlet pressure (P), temperature (T), and valve switch status (ON, OFF) are extracted as compressor attributes.

[0237] 8. The compressor module is also characterized by a state machine of the compressor module: state 1 is the initial state of the compressor, state 2 is the compressor cooling state, state 3 is the cooling stop state, state 4 is the switch compressor operation state; state 5 is the compressor shutdown state; state 6 is the compressor pressure relief state; state 7 is the pressure relief end state.

[0238] 9. The compressor module is also characterized in that the cooling on / off command, the valve on / off command, the compressor start command and the shutdown command are used as input parameters; and the state transition is triggered by the input parameters.

[0239] 10. The tank module is characterized in that the tank body, tank outlet and inlet valves, pressure and displacement sensors, etc. are encapsulated in one module.

[0240] 11. The tank module is also characterized in that the tank pressure (P), the remaining volume (H), and the valve switch state (ON, OFF) are extracted as tank attributes;

[0241] 12. The tank module is also characterized by a tank module state machine: state 1 is the initial state of the tank, state 2 is the state of the tank supplying air to the compressor, state 3 is the state of the compressor evacuating air from the tank, state 4 is the low-pressure state of the tank, state 5 is the propellant replenishment flow state, state 6 is the propellant replenishment in place state; state 7 is the tank pressurization state; state 8 is the tank pressurization end state.

[0242] 13. The tank module is also characterized in that the valve switch instruction is used as an input parameter; the state transition is triggered by the input parameter.

[0243] 14. The replenishing liquid circuit module is characterized in that the replenishing interface, the blow-off port and the related valves and pipelines are encapsulated in one module.

[0244] 15. The replenishing liquid circuit module is also characterized in that the replenishing pipeline pressure and valve switch status are extracted as replenishing liquid circuit pipeline module attributes.

[0245] 16. The replenishing liquid circuit module is also characterized by a replenishing liquid circuit pipeline module state machine: state 1 is the initial state of the liquid circuit pipeline module, state 2 is the state after the replenishing propellant pipeline is pressurized, state 3 is the propellant replenishment flow state, state 4 is the propellant replenishment in place state, state 5 is the propellant blow-off state, and state 6 is the blow-off end state.

[0246] 17. The replenishing liquid circuit module is also characterized in that the valve switch instruction is used as an input parameter, and the state conversion is triggered by the input parameter.

[0247] 18. The propellant replenishing system test model is also characterized by using an empirical formula to describe the changes in attribute parameters during the state conversion process: for example, pressure P = P0 + Pd t; where P0 is the pressure in the previous state, Pd is the pressure change coefficient, and t is time.

[0248] 19. The propellant replenishing system test model is also characterized in that the instructions generated by the control algorithm and program are used as input instructions to trigger the state machine transition, and the attribute parameters of the replenishing system test model are fed back to the replenishing control system as output, thereby realizing the verification of the replenishing control system algorithm and program.

[0249] Embodiment 5:

[0250] Embodiment 5 is a preferred example of Embodiment 1, and is used to illustrate the present invention in more detail.

[0251] Reference Figure 2 The propellant replenishment system model includes four basic modules, which are coupled with the replenishment control system through data flow. The replenishment control system outputs control instructions. The propellant replenishment system model uses the control instructions as state machine trigger parameters to achieve state transition. The attribute changes of the state transition are fed back to the replenishment control system as output parameters to achieve closed-loop verification of the replenishment control algorithm and program. The specific steps are as follows:

[0252] Step 1: The propellant replenishing system model is divided into four basic modules: a gas cylinder module (2), a gas compressor module (3), a tank module (4), and a liquid pipeline module (5).

[0253] Step 2: Build the gas cylinder module model

[0254] The gas cylinder module structure is as follows:

[0255] a) Gas cylinder module scope: including gas cylinder body, valve L1, valve L2 and related pipelines;

[0256] b) Gas cylinder attribute parameters: gas cylinder pressure P, switch status of valve L1 and valve L2;

[0257] c) Input parameters: valve L1, valve L2 switch instructions, operating time t;

[0258] d) Output parameters: bottle pressure P, switch status of valve L1 and valve L2.

[0259] like Figure 2 , the gas cylinder module has 5 states:

[0260] a) State 1 is the initial state of the gas cylinder model. When time T = 0, the gas cylinder pressure P = P0, valves L1 and L2 are both in the closed state (OFF), and P0 is determined according to the design parameters of the replenishment system;

[0261] b) State 2 is the state where the compressor pressurizes the gas cylinder. When the valve L1 opening command is triggered, the valve L1 state changes from closed to open, and the gas cylinder pressure increases from P0 to Pt, Pt = P0 + K*Δt, K is the pressurization coefficient, Δt = t-tON time, t is the current time, tON is the moment when the valve L1 opening command is received, and Pt is the value of the gas cylinder pressure at time t;

[0262] c) State 3 is the high-pressure state of the gas cylinder. The compressor stops pressurizing the gas cylinder. When the valve L1 closing command is triggered, the valve L1 state changes from open to closed, and the gas cylinder pressure Pt no longer increases. Pt = P0 + K * ΔtOFF, K is the pressurization coefficient, ΔtOFF = tOFF - tON, and time tOFF is the moment when the valve L1 closing command is received;

[0263] d) State 4 is the state where the gas cylinder pressurizes the tank. When the valve L2 opening command is triggered, the valve L2 state changes from closed to open, and the gas cylinder pressure changes from the current pressure to Pt, where Pt = Pcurrent + K*Δt, K is the pressure increase coefficient, Pcurrent is the current state pressure, that is, the gas cylinder pressure before the valve L2 opening command is received, Δt = t-tON time, t is the current time, and tON is the time when the valve L2 opening command is received;

[0264] e) State 5 is the low-pressure state of the gas cylinder. The gas cylinder has finished pressurizing the tank. When the valve L2 closing command is triggered, the valve L2 state changes from open to closed, and the gas cylinder pressure Pt no longer decreases. Pt = P0 + K * ΔtOFF, K is the pressurization coefficient, ΔtOFF = tOFF - tON\, and time tOFF is the moment when the valve L2 closing command is received;

[0265] Step 3: Build the compressor module model

[0266] The compressor module structure is as follows:

[0267] a) State 5 is the compressor shutdown state, which is triggered by the compressor shutdown command. The compressor inlet pressure is maintained at a fixed value P1=C1, and the outlet pressure no longer increases P2=P20+KΔtOFF, ΔtOFF=tOFF-tON, tOFF is the moment when the compressor shutdown command is received, tON is the moment when the compressor start command is received, and K is the boost coefficient;

[0268] b) State 6 is the compressor pressure relief state, which is triggered by the valve L4 opening command. The compressor inlet pressure is fixed at P1=C1, and the outlet pressure is reduced to P2=P2ON+KΔtON, ΔtON=t-tON, t is the current time, tON is the time when the valve L4 opening command is received, P2ON is the compressor outlet pressure corresponding to tON, and K is the coefficient of variation;

[0269] c) State 7 is the end state of pressure relief, which is triggered by the valve L4 closing command. The compressor inlet pressure is maintained at a fixed value P1=C1, and the outlet pressure is reduced to P2=P2OFF+KΔtOFF, ΔtOFF=tOFF-tON, tOFF is the moment when the valve L4 closing command is received, tON is the moment when the valve L4 opening command is received, P2OFF is the compressor outlet pressure corresponding to the moment tOFF, and K is the coefficient of variation.

[0270] Step 4: Build the tank module model

[0271] The tank module structure is as follows:

[0272] a) Tank module scope: including tank, valve L3 and valve L5 and related pipelines;

[0273] b) Tank attribute parameters: tank pressure P, tank remaining volume H, switch status of valves L3 and L5;

[0274] c) Input parameters: compressor start command, compressor stop command, valve L2, L3, L5 switch command, running time t;

[0275] d) Output parameters: tank pressure P, tank remaining volume H, and switch status of valves L3 and L5.

[0276] As attached Figure 4 , the tank module has 8 states:

[0277] d) State 1 is the initial state of the tank module. When time T = 0, the tank pressure P = P0, the tank residual volume H = H0, and valves L3 and L5 are in the closed state (OFF); P0 is the initial pressure of the tank, and H0 is the initial residual volume of the tank, which is determined according to the design parameters of the replenishment system;

[0278] e) State 2 is the state where the tank supplies air to the compressor, which is triggered by the valve L3 opening command. The tank pressure P = P0-C2, where C2 is a constant and can be 0 or determined based on experimental data;

[0279] f) State 3 is the state where the compressor is evacuating the tank. It is triggered by the compressor start command, and the tank pressure begins to drop. P = PON + KΔt, Δt = t-tON, t is the current time, tON is the moment when the compressor start command is received, PON is the tank pressure corresponding to tON, and K is the coefficient of variation;

[0280] g) State 4 is the tank low pressure state, which is triggered by the compressor shutdown command. The tank pressure drops to the low pressure state P=PON1+KΔtOFF, ΔtOFF=tOFF-tON1, tOFF is the moment when the compressor shutdown command is received, tON1 is the moment when the compressor start command is received, K is the variation coefficient, and PON1 is the tank pressure corresponding to tON1;

[0281] h) State 5 is the propellant replenishment state, which is triggered by the valve L5 opening command. The remaining amount in the tank increases by H=H0+K1ΔtON2, and the tank pressure increases by P=PON2+K2ΔtON2, where tON2 is the moment when the valve L5 opening command is received, PON2 is the tank pressure corresponding to the moment tON2, ΔtON2=t-tON2, t is the current moment, and K1 and K2 are the coefficients of variation;

[0282] i) State 6 is the tank replenishment state, which is triggered by the valve L5 closing command. The remaining amount and pressure in the tank are fixed and no longer increase: H = H0 + K1ΔtOFF, P = PON2 + K2ΔtOFF, ΔtOFF = tOFF-tON, tOFF is the moment when valve L5 receives the closing command, tON is the moment when valve L5 receives the opening command, PON2 is the tank pressure corresponding to the moment tON2, tON2 is the moment when valve L5 receives the opening command, K1 and K2 are the coefficients of variation;

[0283] j) State 7 is the state where the gas cylinder pressurizes the tank, which is triggered by the valve L2 opening command, and the tank pressure increases, P = PON3 + K2ΔtON3, ΔtON3 = t-tON3, t is the current time, tON3 is the time when the valve L2 opening command is received, PON3 is the tank pressure corresponding to the time tON3, and K is the coefficient of change;

[0284] k) State 8 is the end state of the gas cylinder pressurizing the tank, which is triggered by the valve L2 closing command. The tank pressure increases to a fixed value, P = PON3 + K2ΔtOFF, ΔtOFF = tOFF-tON3, tOFF is the moment when the valve L2 closing command is received, tON3 is the moment when the valve L2 opening command is received, PON3 is the tank pressure corresponding to the moment tON3, and K is the coefficient of variation.

[0285] Step 5: Establish the replenishment fluid circuit module model

[0286] The model structure of the replenishing liquid circuit module is as follows:

[0287] a) Scope of the replenishing liquid pipeline module: replenishing interface, blow-off port, valves L6, 7, 8, 9 and related pipelines;

[0288] b) Parameters of the replenishing liquid circuit module: replenishing pipeline pressure P, switch status of valves L6, 7, 8, 9;

[0289] c) Input parameters: valve L6, 7, 8, 9 switch instructions, operating time t;

[0290] d) Output parameters: Supplementary pipeline pressure P, switch status of valves L6, 7, 8, and 9.

[0291] like Figure 2 , the replenishing liquid pipeline module has 6 states:

[0292] a) State 1 is the initial state of the replenishing liquid pipeline module. When time T=0, the replenishing liquid pipeline pressure P=P0, the storage valves L6, L7, L8, and L9 are in the closed state (OFF), and P0 is the initial state pressure of the liquid pipeline module, which is determined according to the design parameters of the replenishing system;

[0293] b) State 2 is the pressurization state of the replenishing liquid pipeline, which is triggered by the start-up command of valve L9. The pressure of the replenishing liquid pipeline P = P1, and P1 is a fixed value determined according to the design parameters of the replenishing system;

[0294] c) State 3 is the propellant replenishing state, which is triggered by the valve L6 start command. The replenishing liquid pipeline pressure P = P1 + KΔtON, ΔtON = t-tON, t is the current time, tON is the time when the valve L6 start command is received, and K is the coefficient of change.

[0295] d) State 4 is the state where the propellant is added in place, which is triggered by the valve L6 shutdown command. The pressure of the replenishing liquid pipeline is a fixed value, P = P1 + KΔtOFF, ΔtOFF = tOFF-tON, tOFF is the moment when the L6 shutdown command is received, tON is the moment when the valve L6 start command is received, and K is the coefficient of variation;

[0296] e) State 5 is the propellant blow-off state, which is triggered by the start-up command of valves L7 and 8. The pipeline pressure of the replenishing liquid circuit P=P1+KΔtON, ΔtON=t-tON, t is the current time, tON is the time when the opening command of valves L7 and L8 is received, and K is the coefficient of change;

[0297] f) State 6 is the state after the propellant is blown off, which is triggered by the start-up command of valves L7 and 8. The pipeline pressure of the replenishing liquid circuit is a fixed value P=P2, and P2 can be taken as 0 or determined according to the design parameters of the replenishing system.

[0298] Those skilled in the art know that, in addition to implementing the system, device and its various modules provided by the present invention in a purely computer-readable program code, it is entirely possible to implement the same program in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers and embedded microcontrollers by logically programming the method steps. Therefore, the system, device and its various modules provided by the present invention can be considered as a hardware component, and the modules included therein for implementing various programs can also be considered as structures within the hardware component; the modules for implementing various functions can also be considered as both software programs for implementing the method and structures within the hardware component.

[0299] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A propellant replenishment system test system based on a state machine, characterized in that: include: Gas cylinder module: includes gas cylinder, transverse valve, longitudinal valve and pressure sensor. The pressure sensor is located at the outlet of the gas cylinder and indicates the pressure of the gas cylinder. The transverse valve is connected to the pressurization system, and the longitudinal valve is connected to the storage tank. Compressor module: includes compressor, inlet and outlet pipelines and valves. The compressor outlet pipeline is connected to the gas cylinder, and the compressor inlet pipeline is connected to the tank. The valve is a compressor pressure relief valve. Tank module: includes a tank, a tank outlet valve, a tank inlet valve, a pressure sensor, and a displacement sensor. The pressure sensor is located at the tank inlet and indicates the tank pressure; the displacement sensor is located inside the tank and indicates the volume of the tank propellant; the tank inlet valve is connected to the compressor module, and the tank inlet pipeline is connected to the gas cylinder; the tank outlet valve and pipeline are connected to the liquid pipeline; Liquid pipeline module: including interfaces, related valves and pipelines. The replenishing interface is the propellant input interface, and the output interface is connected to the tank; the blow-off interface is the outlet for the propellant blow-off. The replenishing interface, output interface and blow-off interface are isolated by valves respectively; The empirical formula is used to describe the changes in attribute parameters during the state transition process: P=P0+Pd*t P is pressure, P0 is the pressure in the previous state, Pd is the pressure change coefficient, and t is time; The input parameters of state transition, except attribute parameters, are generated by control algorithms and programs to verify control algorithms and programs; Each functional module is abstracted and encapsulated, the internal behavior of the module is described by a state machine, and the modules and the replenishment control system are coupled by interface parameters to form a propellant replenishment system test model; In the gas cylinder module: The valve switch command generated by the control algorithm is used as an input parameter to trigger the state transition; Extract test-related pressure and valve switch status as cylinder attributes; The attribute represents the state of the module and is fed back to the supplementary control system as an output signal; The valve switch command is issued by the replenishment control system. After receiving the command, the gas cylinder module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete the program algorithm verification. A state machine is used to describe the behavior of the gas cylinder during the refueling process; state 1 is the initial state of the gas cylinder, state 2 is the state of the compressor pressurizing the gas cylinder, state 3 is the high-pressure state of the gas cylinder, state 4 is the state of the gas cylinder pressurizing the tank, and state 5 is the low-pressure state of the gas cylinder; different states and transitions represent the operations that the gas cylinder needs to perform at different stages of the refueling process and the responses after the operations. A state machine is used to describe the behavior of the gas cylinder during the refueling process; State transitions are triggered by input parameters; The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program algorithm. In the compressor module: Use the cooling on / off command, valve on / off command, compressor start / stop command as input parameters to trigger state transition; Extract the compressor inlet and outlet pressures and temperatures and valve switch status as compressor attributes; The cooling on / off command, valve on / off command, compressor start / shutdown command are issued by the supplementary control system. After receiving the command, the compressor module simulates the corresponding changes in the property parameters of the physical system and feeds back to the supplementary control system. The supplementary control system uses the feedback signal to complete the program algorithm verification. The state machine is used to describe the compressor behavior during the charging process: state 1 is the initial state of the compressor, state 2 is the compressor cooling state, state 3 is the cooling stop state, state 4 is the switch compressor operation state; state 5 is the compressor shutdown state; state 6 is the compressor pressure relief state; state 7 is the pressure relief end state, State transitions are triggered by input parameters; The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program and algorithm.

2. The state machine-based propellant replenishment system test system according to claim 1, characterized in that: In the tank module: The valve switch command is used as an input parameter to trigger the state transition; Extracting tank pressure, remaining volume and valve switch status as tank attributes; The valve switch command is issued by the replenishment control system. After receiving the command, the tank module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete the program algorithm verification. The state machine is used to describe the behavior of the tank module during the replenishment process: state 1 is the initial state of the tank, state 2 is the state of the tank supplying air to the compressor, state 3 is the state of the compressor pumping air from the tank, state 4 is the low-pressure state of the tank, state 5 is the propellant replenishment flow state, state 6 is the propellant replenishment in place state; state 7 is the tank pressurization state; state 8 is the tank pressurization end state; State transitions are triggered by input parameters; The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program algorithm.

3. The state machine-based propellant replenishment system test system according to claim 1, characterized in that: In the fluid pipeline module: The valve switch command is used as an input parameter to trigger the state transition; Extract the replenishment pipeline pressure and valve switch status as the replenishment pipeline module attributes; The input parameter is the valve switch command; The valve switch command is issued by the replenishment control system. After receiving the command, the liquid pipeline module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete the program algorithm verification. The state machine is used to describe the behavior of the liquid pipeline module during the replenishment process: state 1 is the initial state of the liquid pipeline module, state 2 is the state after the propellant pipeline is pressurized, state 3 is the propellant replenishment flow state, state 4 is the propellant replenishment completion state, state 5 is the propellant blow-off state, and state 6 is the blow-off end state; State transitions are triggered by input parameters; The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program algorithm.

4. A propellant replenishment system testing method based on a state machine, characterized in that: The propellant replenishment system test system based on the state machine of claim 1 is used to perform the following steps: Step S1: The gas cylinder module, the gas compressor module, the storage tank module and the liquid pipeline module receive relevant instructions from the replenishment control system; Step S2: Simulate the state change of the physical system, and output the attribute parameters for feedback transmission to the supplementary control system; Step S3: The additional control system automatically determines whether the algorithm and program for module operation are correct through the feedback signal; The empirical formula is used to describe the changes in attribute parameters during the state transition process: P=P0+Pd*t P is pressure, P0 is the pressure in the previous state, Pd is the pressure change coefficient, and t is time; The input parameters of state transition, except attribute parameters, are generated by control algorithms and programs to verify control algorithms and programs; In the gas cylinder module: The valve switch command generated by the control algorithm is used as an input parameter to trigger the state transition; Extract test-related pressure and valve switch status as cylinder attributes; The attribute represents the state of the module and is fed back to the supplementary control system as an output signal; The valve switch command is issued by the replenishment control system. After receiving the command, the gas cylinder module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete the program algorithm verification. A state machine is used to describe the behavior of the gas cylinder during the refueling process; state 1 is the initial state of the gas cylinder, state 2 is the state of the compressor pressurizing the gas cylinder, state 3 is the high-pressure state of the gas cylinder, state 4 is the state of the gas cylinder pressurizing the tank, and state 5 is the low-pressure state of the gas cylinder; different states and transitions represent the operations that the gas cylinder needs to perform at different stages of the refueling process and the responses after the operations. A state machine is used to describe the behavior of the gas cylinder during the refueling process; State transitions are triggered by input parameters; The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program algorithm. In the compressor module: Use the cooling on / off command, valve on / off command, compressor start / stop command as input parameters to trigger state transition; Extract the compressor inlet and outlet pressures and temperatures and valve switch status as compressor attributes; The cooling on / off command, valve on / off command, compressor start / shutdown command are issued by the supplementary control system. After receiving the command, the compressor module simulates the corresponding changes in the property parameters of the physical system and feeds back to the supplementary control system. The supplementary control system uses the feedback signal to complete the program algorithm verification. The state machine is used to describe the compressor behavior during the charging process: state 1 is the initial state of the compressor, state 2 is the compressor cooling state, state 3 is the cooling stop state, state 4 is the switch compressor operation state; state 5 is the compressor shutdown state; state 6 is the compressor pressure relief state; state 7 is the pressure relief end state, State transitions are triggered by input parameters; The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program and algorithm.

5. The state machine-based propellant replenishment system testing method according to claim 4, characterized in that: In the tank module: The valve switch command is used as an input parameter to trigger the state transition; Extracting tank pressure, remaining volume and valve switch status as tank attributes; The valve switch command is issued by the replenishment control system. After receiving the command, the tank module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete the program algorithm verification. The state machine is used to describe the behavior of the tank module during the replenishment process: state 1 is the initial state of the tank, state 2 is the state of the tank supplying air to the compressor, state 3 is the state of the compressor pumping air from the tank, state 4 is the low-pressure state of the tank, state 5 is the propellant replenishment flow state, state 6 is the propellant replenishment in place state; state 7 is the tank pressurization state; state 8 is the tank pressurization end state; State transitions are triggered by input parameters; The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program algorithm.

6. The state machine-based propellant replenishment system testing method according to claim 4, characterized in that: In the fluid pipeline module: The valve switch command is used as an input parameter to trigger the state transition; Extract the replenishment pipeline pressure and valve switch status as the replenishment pipeline module attributes; The input parameter is the valve switch command; The valve switch command is issued by the replenishment control system. After receiving the command, the liquid pipeline module simulates the corresponding changes in the property parameters of the physical system and feeds back to the replenishment control system. The replenishment control system uses the feedback signal to complete the program algorithm verification. The state machine is used to describe the behavior of the liquid pipeline module during the replenishment process: state 1 is the initial state of the liquid pipeline module, state 2 is the state after the propellant pipeline is pressurized, state 3 is the propellant replenishment flow state, state 4 is the propellant replenishment completion state, state 5 is the propellant blow-off state, and state 6 is the blow-off end state; State transitions are triggered by input parameters; The attribute parameters are output signals, describing the state changes caused by the input parameter triggers. The attribute parameters are fed back to the supplementary control system, and the supplementary control system uses the feedback signals to determine the correctness of the program algorithm.

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