Dynamic simulation method of gas equipment system based on digital twinborn technology

Abstract

The invention discloses a dynamic simulation method of a gas equipment system based on a digital twinning technology, which comprises the following steps of: acquiring typical operation conditions of the gas equipment system, acquiring process design parameters of system equipment parts, establishing a static simulation model of the gas equipment system based on the digital twinning technology, and performing dynamic simulation on the gas equipment system based on the digital twinning technology. Inputting the obtained process design parameters of the system equipment component; creating a dynamic simulation model of the gas equipment system; loading an automatic control program of the gas equipment system to the virtual simulator to form a closed-loop dynamic simulation platform; inputting initial operation conditions of a plurality of typical operation conditions of the gas equipment system into the dynamic simulation model to generate operation result parameter information; adjusting strategy information is generated, the adjusting strategy information is substituted into the dynamic simulation model of the gas equipment system, an optimal adjusting strategy of the gas equipment system is obtained, and an automatic control program of the gas equipment system is adjusted; and the simulation effect is accurate.

Description

Technical Field

[0001] The present invention relates to the technical field of LNG gas supply equipment systems, and in particular to a dynamic simulation method for a gas equipment system based on digital twin technology. Background Art

[0002] Gas equipment system refers to the gas equipment system used to provide the required suitable pressure and temperature to gas-using equipment. Gas equipment system generally includes LNG storage tanks, LNG deep well pumps or submersible pumps, gas compressors, high-pressure LNG reciprocating pumps, low-pressure LNG evaporators, high-pressure LNG evaporators, gas coolers, low-pressure gas buffer tanks, high-pressure gas buffer tanks and other equipment. Usually, the gas equipment system must wait until the entire gas equipment system is installed before the entire gas equipment system can be tested. If problems are found, rework and adjustment are required.

[0003] Digital twin technology, as a cutting-edge scientific and technological innovation, has gradually emerged in the early 21st century. Digital twin technology, also known as digital mapping or digital mirroring, refers to the use of tools such as principles, mechanisms and process models in a virtual environment to build a digital model that is completely consistent with the characteristics, behaviors and performance of real physical objects. The state of real physical objects can be predicted through digital model simulation.

[0004] How to use digital twin technology to create static and dynamic simulation models of gas equipment systems and conduct dynamic simulations during the design phase, and to verify and optimize the process flow, dynamic performance and automation control procedures of the gas equipment system in advance before actual ship trials has become a technical problem that needs to be solved.

[0005] Therefore, a dynamic simulation method for a gas equipment system based on digital twin technology is provided to solve the above problems. Summary of the invention

[0006] The technical problem to be solved by the present invention is how to use digital twin technology to create static and dynamic simulation models including a gas equipment system in the design stage, and perform dynamic simulation, so as to verify and optimize the process flow, dynamic performance and automatic control program of the gas equipment system in advance before the actual ship test. Therefore, a dynamic simulation method of a gas equipment system based on digital twin technology is provided, and the dynamic simulation method of a gas equipment system based on digital twin technology includes: Obtain typical operating conditions of the gas equipment system, obtain process design parameters of system equipment components of the gas equipment system under typical operating conditions, establish a static simulation model of the gas equipment system based on digital twin technology, and input the obtained process design parameters of the system equipment components into the static simulation model of the gas equipment system; Establish a connection between the static simulation model of the gas equipment system and the database of the gas equipment system and the signal of the automation control program to create a dynamic simulation model of the gas equipment system; Load the gas equipment system automation control program onto the virtual simulator, and exchange real-time data between the virtual simulator and the dynamic simulation model of the gas equipment system to form a closed-loop dynamic simulation platform; Inputting the initial operating conditions of several typical operating conditions of the gas equipment system into the dynamic simulation model of the gas equipment system, running the automatic control program in the closed-loop dynamic simulation platform, and generating operating result parameter information of the gas equipment system corresponding to several typical operating conditions; Generate adjustment strategy information according to the operation result parameter information of the typical operation condition, substitute the adjustment strategy information into the dynamic simulation model of the gas equipment system, and obtain the optimal adjustment strategy of the gas equipment system; Adjust the automation control program of the gas equipment system according to the optimal adjustment strategy.

[0007] Optionally, the gas equipment system includes a dual-fuel boiler, a first dual-fuel power generation engine, a second dual-fuel power generation engine, a third dual-fuel power generation engine, a high-pressure dual-fuel main propulsion engine, a first main gas valve, a second main gas valve, a third main gas valve, a low-temperature gas buffer tank, a pressure regulating valve, a gas compressor, a compressor bypass control valve, a low-pressure LNG evaporator, a high-pressure gas buffer tank, a high-pressure LNG evaporator, a high-pressure LNG reciprocating pump, a reciprocating pump bypass control valve, a low-pressure pump bypass control valve, an LNG storage tank, an LNG submersible pump and an LNG deep well pump, the LNG storage tank is provided with an LNG deep well pump and an LNG submersible pump, the LNG storage tank is connected to the gas compressor through a pipeline, the gas compressor is connected to the gas cooler, a bypass is provided on the side of the gas compressor and the gas cooler, and a compressor bypass control valve is provided on the bypass. control valve, one end of the pressure regulating valve is connected to the gas cooler, the other end of the pressure regulating valve is connected to the low-pressure gas buffer tank, the low-pressure gas buffer tank is connected to the third main gas valve, and the third main gas valve is connected to the dual-fuel boiler; the LNG deep well pump is simultaneously connected to the low-pressure pump bypass control valve, the high-pressure LNG reciprocating pump and the low-pressure LNG evaporator, the low-pressure LNG evaporator is connected to the low-pressure gas buffer tank, the low-pressure gas buffer tank is connected to the second main gas valve, and the second main gas valve is simultaneously connected to the first dual-fuel power generation engine, the second dual-fuel power generation engine and the third dual-fuel power generation engine; the high-pressure LNG reciprocating pump is connected to the high-pressure LNG evaporator, a bypass is provided on the side of the high-pressure LNG reciprocating pump, and a reciprocating pump bypass control valve is provided on the bypass, one end of the high-pressure gas buffer tank is connected to the high-pressure LNG evaporator, the other end of the high-pressure gas buffer tank is connected to the first gas valve, and the first main gas valve is connected to the high-pressure dual-fuel main propulsion engine.

[0008] Optional, typical operating conditions include: The first typical operating condition: the stable operating condition of high-pressure gas at the maximum flow rate and the instantaneous switching from the stable operating condition of high-pressure gas at the maximum flow rate to the emergency gas cut-off condition; The second typical operating condition: the stable operating condition of low-pressure gas at the maximum flow rate and the instantaneous switching from the stable operating condition of low-pressure gas at the maximum flow rate to the emergency gas cut-off condition; The third typical operating condition: a stable operating condition with high-pressure and low-pressure gas supplied simultaneously at the maximum flow rate and an instantaneous switch from a stable operating condition with high-pressure and low-pressure gas supplied simultaneously at the maximum flow rate to an emergency gas cut-off condition; The fourth typical operating condition: stable operation of high-pressure and low-pressure gas supply at the maximum flow rate is switched to stable operation of high-pressure and low-pressure gas supply at the minimum flow rate; The specific process of the first typical operating condition includes: Start the LNG deep well pump or submersible pump, and use the LNG transported by the LNG deep well pump or submersible pump to precool the high-pressure LNG reciprocating pump. When the temperature of the high-pressure LNG reciprocating pump is precooled to below -130°C, start the high-pressure LNG reciprocating pump, switch the high-pressure dual-fuel main propulsion engine to gas operation, open the main gas valve of the high-pressure dual-fuel main propulsion engine, load the high-pressure dual-fuel main propulsion engine to 100% load, and operate the high-pressure gas stably at the maximum flow rate; then the high-pressure dual-fuel main propulsion engine is instantly cut off from gas due to a fault, and switched to fuel mode operation; The specific process of the second typical operating condition includes: Start the LNG deep well pump or submersible pump, start the gas compressor, switch the three low-pressure dual-fuel generator engines and one low-pressure dual-fuel boiler from fuel oil mode to gas operation one by one, open the main gas valve of the generator engine and the main gas valve of the boiler, adjust the load of the three generator engines to 70% load, and adjust the load of one boiler to 100% load, and the low-pressure gas runs stably at the maximum flow rate; then the three generator engines and one boiler are cut off from gas at the same time due to a fault, and the three generator engines are switched to fuel oil mode, and one boiler stops running; The specific process of the third typical operating condition includes: Start the LNG deep well pump or submersible pump, start the gas compressor, switch two low-pressure dual-fuel generator engines and one low-pressure dual-fuel boiler from fuel oil mode to gas operation one by one, open the main gas valve of the generator engine and the main gas valve of the boiler, adjust the gas operation load of the two generator engines to 55% load, and adjust the gas operation load of one boiler to 45% load, use the LNG transported by the LNG deep well pump or submersible pump to precool the high-pressure LNG reciprocating pump, wait for the high-pressure LNG reciprocating pump to be precooled to a temperature below -130°C, start the high-pressure LNG reciprocating pump, switch the high-pressure dual-fuel main propulsion engine from fuel oil mode to gas operation, open the main gas valve of the high-pressure dual-fuel main propulsion engine, and load the high-pressure dual-fuel main propulsion engine to 100% load. At this time, the high-pressure and low-pressure gas are simultaneously supplied and run stably at the maximum flow rate; then the high-pressure dual-fuel main propulsion engine, two generator engines and one boiler are cut off from gas at the same time due to a fault, and the high-pressure dual-fuel main propulsion engine and two generator engines are changed to fuel oil mode, and one boiler stops running; The specific process of the fourth typical operating condition includes: Start the LNG deep well pump or submersible pump, start the gas compressor, switch two low-pressure dual-fuel generator engines and one low-pressure dual-fuel boiler from fuel mode to gas operation one by one, open the main gas valve of the generator engine and the main gas valve of the boiler, adjust the gas operation load of the two generator engines to 55% load, and adjust the gas operation load of one boiler to 45% load. Use the LNG transported by the LNG deep well pump or submersible pump to precool the high-pressure LNG reciprocating pump. When the temperature of the high-pressure LNG reciprocating pump is precooled to below -130℃, start the high-pressure LNG reciprocating pump, and the high-pressure dual-fuel main propulsion engine is switched from The fuel mode is switched to gas operation, the main gas valve of the high-pressure dual-fuel main propulsion engine is opened, and the load of the high-pressure dual-fuel main propulsion engine is loaded to 100% load. At this time, high-pressure and low-pressure gas are supplied simultaneously and operate stably at the maximum flow rate; then, a generator engine and a boiler are cut off from gas at the same time due to a fault. The generator engine is switched to fuel mode operation, and the boiler stops running. The gas operating load of the high-pressure dual-fuel main propulsion engine is adjusted to 10% load, and the gas operating load of the other generator engine is adjusted to 40%. At this time, high-pressure and low-pressure gas are supplied simultaneously and operate stably at the minimum flow rate.

[0009] Optionally, the establishment of a static simulation model of a gas equipment system based on digital twin technology includes: The process design parameters of each equipment component in the gas equipment system are obtained respectively, and the physical relationship sub-model of the gas equipment system and each equipment component is constructed, and the physical relationship sub-model includes: the physical relationship sub-model of LNG storage tank pressure and temperature; the physical relationship sub-model of LNG deep well pump or submersible pump flow and head; the physical relationship sub-model of gas compressor flow, exhaust pressure and temperature; the physical relationship sub-model of high-pressure LNG reciprocating pump flow and head; the physical relationship sub-model of low-pressure LNG evaporator liquid and gas two-phase flow conversion; the physical relationship sub-model of high-pressure LNG evaporator liquid and gas two-phase flow conversion; the physical relationship sub-model of gas cooler gas heat exchange; the physical relationship sub-model of LNG liquid and gas pipeline flow and pressure loss; the physical relationship sub-model of gas-using equipment load setting; Based on the physical relationship sub-models of the gas equipment system and each equipment component, a multi-physical quantity static simulation sub-model of each component is constructed in one-to-one correspondence with the physical relationship sub-model; According to the physical process flow and numerical calculation relationship between each system equipment component of the gas equipment system, the static simulation sub-models of each system equipment component of the gas equipment system are connected to create a complete static simulation model of the gas equipment system.

[0010] Optionally, the initial operating conditions are the initial set values ​​for the operation of the dynamic simulation model of the gas equipment system, including the initial liquid level height, initial pressure, initial temperature, external ambient temperature, composition of the LNG storage tank, the composition ratio of water glycol as the heat exchange medium of the LNG evaporator, the initial state of the gas equipment system and the gas-using equipment, and the load setting of the gas-using equipment.

[0011] Optionally, the generating the adjustment strategy information according to the operation result parameter information of the typical operation condition includes: Based on the dynamic simulation model of the gas equipment system, according to the workflow of one of the selected typical operating conditions, initial operating conditions are input into the dynamic simulation model of the gas equipment system, the automatic control program of the gas equipment system is run through the PLC virtual simulator, and real-time data is exchanged with the dynamic simulation model of the gas equipment system, the dynamic simulation model of the gas equipment system is updated, and current operating result parameters of the dynamic simulation model of the gas equipment system in the current operating condition are obtained; Compare the current operating result parameters with the process design parameters of the same operating condition to obtain the current difference value of the current operating condition. If the current difference value does not meet the design limit value, analyze and obtain the adjustment strategy of the automatic control program of the gas equipment system under the current operating condition; Based on the operation result parameters of the dynamic simulation model of the different typical operation conditions, multiple adjustment strategies of the automatic control program of the gas equipment system are analyzed and generated.

[0012] Optionally, the operating result parameters of the dynamic simulation model of the gas equipment system include operating result parameters of the pressure and temperature of the gas supply from the gas equipment system to the gas-consuming equipment changing over time; the steady-state value and instantaneous change value of the gas supply pressure and temperature are obtained from the operating result parameters of the pressure and temperature changing over time.

[0013] Optionally, the optimal adjustment strategy for the automation control program of the gas equipment system includes performing a linear programming algorithm of the simplex method based on the multiple adjustment strategies, and performing calculation iterations until the optimal adjustment strategy for the automation control program is found.

[0014] Optionally, the closed-loop dynamic simulation platform includes loading the automation control program of the gas equipment system into a PLC virtual simulator, simulating a PLC controller through the PLC virtual simulator to run the automation control program of the gas equipment system, and performing real-time data exchange with a dynamic simulation model of the gas equipment system to form a closed-loop dynamic simulation platform; The closed-loop dynamic simulation platform is used to simulate the dynamic changes in temperature and pressure of liquid and gaseous LNG in a gas equipment system over time.

[0015] Optionally, the process of establishing the dynamic simulation model of the gas equipment system specifically includes: By establishing a signal and database connection between the static simulation model of the gas equipment system and the automatic control program of the gas equipment system; Input signals and data required by the automatic control program of the gas equipment system are input into the static simulation model of the gas equipment system; or output signals and data required by the automatic control program of the gas equipment system are output from the static simulation model of the gas equipment system; Form a dynamic simulation model of the gas equipment system; The specific process of establishing a signal and database connection between the static simulation model of the gas equipment system and the automatic control program of the gas equipment system includes: According to the interface information of the automatic control program of the gas equipment system, the static simulation model of the gas equipment system is configured with input and output signals; adding the output signal of the automatic control program of the gas equipment system as the input signal of the static simulation model of the gas equipment system to the static simulation model of the gas equipment system; Similarly, the input signal required by the gas equipment system automation control program is the signal output calculated from the static simulation model of the gas equipment system. It needs to be extracted from the static simulation model of the gas equipment system according to the position and feedback information of the sensors in the actual gas equipment system and fed back to the gas equipment system automation control program as an input signal.

[0016] Optionally, the collected process design parameters of the system equipment components are input into the static simulation model to simulate the flow, temperature and pressure conditions of the gas equipment system of liquid and gas phase LNG under a certain system state. It includes inputting the collected process design parameters of the system equipment components of the gas equipment system under various typical operating conditions into the static simulation sub-model of each system equipment component, including: inputting the LNG tank size, volume, cold insulation area, LNG tank pressure at different initial filling rates and natural evaporation rate of LNG in the tank and other parameters into the sub-model of LNG tank pressure and temperature; inputting the pump impeller size, flow rate, pressure, mechanical efficiency and other parameters at different speeds into the sub-model of LNG deep well pump or submersible pump flow and pressure; inputting the suction pressure, suction superheat, exhaust pressure, exhaust temperature, mass flow rate, power, volumetric efficiency, isentropic efficiency and other parameters at different speeds into the sub-model of gas compressor flow, exhaust pressure and temperature; inputting the pump piston size, volume flow rate and pressure at different speeds into the sub-model of high-pressure LNG reciprocating pump flow and pressure; inputting the hot side fluid inlet temperature and volume flow rate, cold side fluid inlet temperature and volume flow rate, heat exchange power, specific heat of heat exchange medium, etc. of the low-pressure LNG evaporator into the sub-model of liquid and gas two-phase flow conversion of the low-pressure LNG evaporator. The pressure loss on the gas side and other parameters are input into the sub-model of the liquid-gas two-phase flow conversion of the high-pressure LNG evaporator, such as the hot-side fluid inlet temperature and volume flow rate, the cold-side fluid inlet temperature and volume flow rate, the heat exchange power, the specific heat of the heat exchange medium, and the pressure loss on the gas side; the hot-side fluid inlet temperature and volume flow rate, the cold-side fluid inlet temperature and volume flow rate, the heat exchange power, the specific heat of the heat exchange medium, and the pressure loss on the gas side of the gas cooler are input into the physical relationship sub-model of the gas heat exchange of the gas cooler; the LNG liquid In the sub-model of flow and pressure loss of phase and gas phase pipelines, the inner diameter and length dimensions and other parameters of the LNG liquid and gas phase pipelines are input; in the sub-model of gas switching and operation signal interaction of gas-using equipment, the interactive signal parameters for gas switching and operation between the gas equipment system and the gas-using equipment are input to simulate the switching of gas-using equipment from fuel mode to gas mode and its operation; in the sub-model of load setting of gas-using equipment, the gas pressure, temperature, flow value and fluctuation limit value parameters required by the gas-using equipment under different gas loads are input.

[0017] The implementation of the present invention has the following beneficial effects: Usually, the gas equipment system can only be tested after the entire gas equipment system is installed on the actual ship. If problems are found, rework and adjustment are required. This patent uses digital twin technology to create static and dynamic simulation models of the gas equipment system and conduct dynamic simulation to verify and optimize the process flow, dynamic performance and automation control program of the gas equipment system in advance before the actual ship test. It has guiding significance for the design and development of the gas equipment system. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a flow chart of a dynamic simulation method of a gas equipment system based on digital twin technology proposed in an embodiment of the present application; Figure 2 It is a simple schematic diagram of the gas equipment system proposed in the embodiment of the present application; Figure 3 It is a structural schematic diagram of a closed-loop dynamic simulation platform proposed in an embodiment of the present application; Figure 4 It is a schematic diagram of a set of gas pressure operation result parameters of the dynamic simulation model proposed in the embodiment of the present application; Figure 5 It is a schematic diagram of the physical relationship between the flow rate and lift of an LNG deep well pump in a multi-physical quantity static model proposed in an embodiment of the present application.

[0019] Figure 6 It is a schematic diagram of the physical relationship between the gas compressor flow, exhaust pressure and temperature in the multi-physical quantity static model proposed in the embodiment of the present application. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Example

[0021] Please refer to the attached drawings of the specification. The technical problem to be solved in this embodiment is how to use digital twin technology to create static and dynamic simulation models including gas equipment systems in the design stage, and perform dynamic simulation, and verify and optimize the process flow, dynamic performance and automatic control program of the gas equipment system in advance before the actual ship test. Therefore, a dynamic simulation of a gas equipment system based on digital twin technology is provided, and the dynamic simulation of a gas equipment system based on digital twin technology includes: Step 1: Obtain the typical operating conditions of the gas equipment system, obtain the process design parameters of the system equipment components of the gas equipment system under typical operating conditions, establish a static simulation model of the gas equipment system based on digital twin technology, and input the obtained process design parameters of the system equipment components into the static simulation model of the gas equipment system.

[0022] Among them, the executor of the dynamic simulation method of the gas equipment system based on digital twin technology in this embodiment can be but is not limited to a dynamic simulation device of the gas equipment system based on digital twin technology, which is implemented by software and hardware and may include but is not limited to a client, a server, etc.

[0023] Among them, the gas equipment system refers to the equipment system used to provide the required gas with suitable pressure, temperature and flow to the gas-using equipment. Figure 2 The figure shows a simple schematic diagram of the gas equipment system proposed in the embodiment of the present application. The gas equipment system includes a dual-fuel boiler, a first dual-fuel power generation engine, a second dual-fuel power generation engine, a third dual-fuel power generation engine, a high-pressure dual-fuel main propulsion engine, a first main gas valve, a second main gas valve, a third main gas valve, a low-temperature gas buffer tank, a pressure regulating valve, a gas compressor, a compressor bypass control valve, a low-pressure LNG evaporator, a high-pressure gas buffer tank, a high-pressure LNG evaporator, a high-pressure LNG reciprocating pump, a reciprocating pump bypass control valve, a low-pressure pump bypass control valve, an LNG storage tank, an LNG submersible pump and an LNG deep well pump. The LNG storage tank is provided with an LNG deep well pump and an LNG submersible pump. The LNG storage tank is connected to the gas compressor through a pipeline. The gas compressor is connected to the gas cooler. A bypass is provided on the side of the gas compressor and the gas cooler, and a compressor bypass control valve is provided on the bypass. , one end of the pressure regulating valve is connected to the gas cooler, the other end of the pressure regulating valve is connected to the low-pressure gas buffer tank, the low-pressure gas buffer tank is connected to the third main gas valve, and the third main gas valve is connected to the dual-fuel boiler; the LNG deep well pump is simultaneously connected to the low-pressure pump bypass control valve, the high-pressure LNG reciprocating pump and the low-pressure LNG evaporator, the low-pressure LNG evaporator is connected to the low-pressure gas buffer tank, the low-pressure gas buffer tank is connected to the second main gas valve, and the second main gas valve is simultaneously connected to the first dual-fuel power generation engine, the second dual-fuel power generation engine and the third dual-fuel power generation engine; the high-pressure LNG reciprocating pump is connected to the high-pressure LNG evaporator, a bypass is provided on the side of the high-pressure LNG reciprocating pump, and a reciprocating pump bypass control valve is provided on the bypass, one end of the high-pressure gas buffer tank is connected to the high-pressure LNG evaporator, the other end of the high-pressure gas buffer tank is connected to the first gas valve, and the first main gas valve is connected to the high-pressure dual-fuel main propulsion engine.

[0024] Among them, the typical operating conditions of the gas equipment system include: The first typical operating condition: the stable operating condition of high-pressure gas at the maximum flow rate and the instantaneous switching from the stable operating condition of high-pressure gas at the maximum flow rate to the emergency gas cut-off condition; The second typical operating condition: the stable operating condition of low-pressure gas at the maximum flow rate and the instantaneous switching from the stable operating condition of low-pressure gas at the maximum flow rate to the emergency gas cut-off condition; The third typical operating condition: a stable operating condition with high-pressure and low-pressure gas supplied simultaneously at the maximum flow rate and an instantaneous switch from a stable operating condition with high-pressure and low-pressure gas supplied simultaneously at the maximum flow rate to an emergency gas cut-off condition; The fourth typical operating condition: stable operation of high-pressure and low-pressure gas supply at the maximum flow rate is switched to stable operation of high-pressure and low-pressure gas supply at the minimum flow rate; The specific process of the first typical operating condition includes: Start the LNG deep well pump or submersible pump, and use the LNG transported by the LNG deep well pump or submersible pump to precool the high-pressure LNG reciprocating pump. When the temperature of the high-pressure LNG reciprocating pump is precooled to below -130°C, start the high-pressure LNG reciprocating pump, switch the high-pressure dual-fuel main propulsion engine to gas operation, open the main gas valve of the high-pressure dual-fuel main propulsion engine, load the high-pressure dual-fuel main propulsion engine to 100% load, and operate the high-pressure gas stably at the maximum flow rate; then the high-pressure dual-fuel main propulsion engine is instantly cut off from gas due to a fault, and switched to fuel mode operation; The specific process of the second typical operating condition includes: Start the LNG deep well pump or submersible pump, start the gas compressor, switch the three low-pressure dual-fuel generator engines and one low-pressure dual-fuel boiler from fuel oil mode to gas operation one by one, open the main gas valve of the generator engine and the main gas valve of the boiler, adjust the load of the three generator engines to 70% load, and adjust the load of one boiler to 100% load, and the low-pressure gas runs stably at the maximum flow rate; then the three generator engines and one boiler are cut off from gas at the same time due to a fault, and the three generator engines are switched to fuel oil mode, and one boiler stops running; The specific process of the third typical operating condition includes: Start the LNG deep well pump or submersible pump, start the gas compressor, switch two low-pressure dual-fuel generator engines and one low-pressure dual-fuel boiler from fuel oil mode to gas operation one by one, open the main gas valve of the generator engine and the main gas valve of the boiler, adjust the gas operation load of the two generator engines to 55% load, and adjust the gas operation load of one boiler to 45% load, use the LNG transported by the LNG deep well pump or submersible pump to precool the high-pressure LNG reciprocating pump, wait for the high-pressure LNG reciprocating pump to be precooled to a temperature below -130°C, start the high-pressure LNG reciprocating pump, switch the high-pressure dual-fuel main propulsion engine from fuel oil mode to gas operation, open the main gas valve of the high-pressure dual-fuel main propulsion engine, and load the high-pressure dual-fuel main propulsion engine to 100% load. At this time, the high-pressure and low-pressure gas are simultaneously supplied and run stably at the maximum flow rate; then the high-pressure dual-fuel main propulsion engine, two generator engines and one boiler are cut off from gas at the same time due to a fault, and the high-pressure dual-fuel main propulsion engine and two generator engines are changed to fuel oil mode, and one boiler stops running; The specific process of the fourth typical operating condition includes: Start the LNG deep well pump or submersible pump, start the gas compressor, switch two low-pressure dual-fuel generator engines and one low-pressure dual-fuel boiler from fuel mode to gas operation one by one, open the main gas valve of the generator engine and the main gas valve of the boiler, adjust the gas operation load of the two generator engines to 55% load, and adjust the gas operation load of one boiler to 45% load. Use the LNG transported by the LNG deep well pump or submersible pump to precool the high-pressure LNG reciprocating pump. When the temperature of the high-pressure LNG reciprocating pump is precooled to below -130℃, start the high-pressure LNG reciprocating pump, and the high-pressure dual-fuel main propulsion engine is switched from The fuel mode is switched to gas operation, the main gas valve of the high-pressure dual-fuel main propulsion engine is opened, and the load of the high-pressure dual-fuel main propulsion engine is loaded to 100% load. At this time, high-pressure and low-pressure gas are supplied simultaneously and operate stably at the maximum flow rate; then, a generator engine and a boiler are cut off from gas at the same time due to a fault. The generator engine is switched to fuel mode operation, and the boiler stops running. The gas operating load of the high-pressure dual-fuel main propulsion engine is adjusted to 10% load, and the gas operating load of the other generator engine is adjusted to 40%. At this time, high-pressure and low-pressure gas are supplied simultaneously and operate stably at the minimum flow rate.

[0025] Among them, the static simulation model of the gas equipment system based on digital twin technology includes the following establishment steps: According to the operating principles and process design parameters of each system equipment component of the gas equipment system, a physical relationship sub-model of the system equipment components of the gas equipment system is constructed; Based on the physical relationship sub-model of the system equipment components of the gas equipment system, using the principle, mechanism or process model and other tools in the digital simulation software, a number of multi-physical quantity static simulation sub-models that can accurately reflect the status of each system equipment component in the gas equipment system are constructed; According to the physical process flow and numerical calculation relationship between each system equipment component of the gas equipment system, the static simulation sub-models of each system equipment component of the gas equipment system are connected to create a complete static simulation model of the gas equipment system.

[0026] Among them, the static simulation sub-model of the gas equipment system based on digital twin technology reflects the characteristics, movement and performance of each system equipment component in the gas equipment system under a specific system state, without considering the impact of time on the state. Multiple multi-physical quantity static simulation sub-models created include: physical relationship sub-model of LNG tank pressure and temperature; physical relationship sub-model of LNG deep well pump or submersible pump flow and head; physical relationship sub-model of gas compressor flow, exhaust pressure and temperature; physical relationship sub-model of high-pressure LNG reciprocating pump flow and head; physical relationship sub-model of low-pressure LNG evaporator liquid and gas two-phase flow conversion; physical relationship sub-model of high-pressure LNG evaporator liquid and gas two-phase flow conversion; physical relationship sub-model of gas cooler gas heat exchange; physical relationship sub-model of LNG liquid and gas pipeline flow and pressure loss; physical relationship sub-model of gas equipment load setting.

[0027] in, Figure 5 It is a schematic diagram of the physical relationship between the flow rate and the lift of the LNG deep well pump in the multi-physical quantity static model. The physical relationship sub-model of the flow rate and the lift of the LNG deep well pump includes the establishment of the physical relationship between the flow rate and the lift.

[0028] Figure 6 It is a schematic diagram of the physical relationship among the gas compressor flow, exhaust pressure and temperature in the multi-physical quantity static model. The physical relationship sub-model of the gas compressor flow, exhaust pressure and temperature includes the establishment of the physical relationship among the gas compressor flow, exhaust pressure and temperature.

[0029] The collected process design parameters of the system equipment components are input into the model, that is, the collected process design parameters of the system equipment components of the gas equipment system under various typical operating conditions are input into the static simulation sub-model of each system equipment component, which is used to simulate the temperature and pressure conditions of the gas equipment system of liquid and gas phase LNG under a certain system state, including: inputting parameters such as LNG tank size, volume, cold insulation area, LNG tank pressure at different initial filling rates and natural evaporation rate of LNG in the tank into the sub-model of LNG tank pressure and temperature; inputting parameters such as LNG deep well pump or submersible pump Input the pump impeller size, flow rate, pressure, mechanical efficiency and other parameters at different speeds into the flow and pressure sub-model; input the suction pressure, suction superheat, exhaust pressure, exhaust temperature, mass flow rate, power, volumetric efficiency, isentropic efficiency and other parameters at different speeds into the gas compressor flow, exhaust pressure and temperature sub-model; input the pump piston size, volume flow rate and pressure at different speeds into the high-pressure LNG reciprocating pump flow and pressure sub-model; input the hot side fluid inlet temperature and volume flow rate of the low-pressure LNG evaporator into the sub-model of the conversion of the liquid and gas phases of the low-pressure LNG evaporator. The parameters such as total flow rate, cold side fluid inlet temperature and volume flow rate, heat exchange power, specific heat of heat exchange medium, and pressure loss on the gas side are input into the sub-model of liquid-gas two-phase flow conversion of high-pressure LNG evaporator. The parameters such as hot side fluid inlet temperature and volume flow rate, cold side fluid inlet temperature and volume flow rate, heat exchange power, specific heat of heat exchange medium, and pressure loss on the gas side are input into the sub-model of liquid-gas two-phase flow conversion of high-pressure LNG evaporator. The parameters such as hot side fluid inlet temperature and volume flow rate, cold side fluid inlet temperature and volume flow rate, heat exchange power, and specific heat of heat exchange medium are input into the physical relationship sub-model of gas heat exchange of gas cooler. , and the pressure loss on the gas side; in the sub-model of LNG liquid and gas pipeline flow and pressure loss, input the parameters such as the inner diameter and length dimensions of each LNG liquid and gas pipeline; in the sub-model of gas switching and operation signal interaction of gas-using equipment, input the interactive signal parameters for gas switching and operation between the gas equipment system and the gas-using equipment, which is used to simulate the switching of gas-using equipment from fuel mode to gas mode and operation; in the sub-model of gas equipment load setting, input the gas pressure, temperature, flow value and fluctuation limit value parameters required by the gas-using equipment under different gas loads.

[0030] Step 2: Establish a connection between the static simulation model of the gas equipment system and the database of the gas equipment system and the signal of the automation control program to create a dynamic simulation model of the gas equipment system.

[0031] Among them, by connecting the signals and database between the static simulation model of the gas equipment system and the automation control program of the gas equipment system, the output or input signals and data required by the automation control program of the gas equipment system are input or output in the static simulation model of the gas equipment system to form a dynamic simulation model of the gas equipment system.

[0032] Among them, a signal and database connection is established between the static simulation model of the gas equipment system and the automatic control program of the gas equipment system, including configuring the input and output signals of the static simulation model of the gas equipment system according to the interface information of the automatic control program of the gas equipment system, and adding the output signal of the automatic control program of the gas equipment system as the input signal of the static simulation model of the gas equipment system to the static simulation model of the gas equipment system; similarly, the input signal required by the automatic control program of the gas equipment system is the signal output calculated by the static simulation model of the gas equipment system, which needs to be extracted from the static simulation model of the gas equipment system according to the position and feedback information of the sensor in the actual gas equipment system and fed back to the automatic control program of the gas equipment system as the input signal.

[0033] Step 3: Load the gas equipment system automation control program onto the virtual simulator, and exchange data between the virtual simulator and the dynamic simulation model of the gas equipment system in real time to form a closed-loop dynamic simulation platform for simulating the dynamic changes in temperature and pressure of liquid and gaseous LNG in the gas equipment system over time.

[0034] Among them, the PLC virtual simulator is a software that can create a virtual PLC controller. The automation control program for running the gas equipment system described in this application can be but is not limited to running the automation program of the gas equipment system through the PLC virtual simulator. The PLC entity can also be used instead of the PLC virtual simulator to realize the operation of the automation control program of the gas equipment system.

[0035] Among them, Figure 3 Shown is a structural schematic diagram of a closed-loop dynamic simulation platform.

[0036] Step 4: Based on the closed-loop dynamic simulation platform, the initial operating conditions of several typical operating conditions of the gas equipment system are input into the dynamic simulation model of the gas equipment system, and the automatic control program is run in the simulation dynamic model to generate operating result parameter information corresponding to several typical operating conditions of the gas equipment system.

[0037] The initial operating conditions are the initial setting values ​​for the operation of the dynamic simulation model of the gas equipment system, including the initial liquid level, initial pressure and initial temperature of the LNG storage tank, the external ambient temperature, the composition of LNG, the composition ratio of water glycol as the heat exchange medium of the LNG evaporator, the initial state of the gas equipment system and the gas-using equipment, the load setting of the gas-using equipment, etc. The initial state of the gas equipment system and the gas-using equipment, and the load setting of the gas-using equipment change with the operating conditions. The composition of LNG is determined by the quality of the LNG added.

[0038] Among them, the operating result parameters of the dynamic simulation model of the gas equipment system include the operating result parameters of the pressure and temperature of the gas supply from the gas equipment system to the gas-consuming equipment changing with time, and the steady-state value and instantaneous change value of the gas supply pressure and temperature are obtained from the operating result parameters of the pressure and temperature changing with time.

[0039] The gas-using equipment includes high-pressure dual-fuel main propulsion engines, low-pressure dual-fuel power generation engines, and low-pressure dual-fuel boilers. These gas-using equipment can use either fuel oil or gas as fuel. The number of gas-using equipment includes but is not limited to Figure 2 Number of devices shown.

[0040] Step 5: Generate adjustment strategy information according to the operation result parameter information of the typical operation condition, substitute the adjustment strategy information into the dynamic simulation model of the gas equipment system, and obtain the optimal adjustment strategy of the gas equipment system.

[0041] Among them, the multiple adjustment strategies of the automatic control program of the gas equipment system include: Based on the dynamic simulation model of the gas equipment system, according to the workflow of one of the selected typical operating conditions, the initial operating conditions are input into the dynamic simulation model of the gas equipment system, the automatic control program of the gas equipment system is run through the PLC virtual simulator, and real-time data is exchanged with the dynamic simulation model of the gas equipment system, the dynamic simulation model of the gas equipment system is updated, and the current operating result parameters of the dynamic simulation model of the gas equipment system in the current operating condition are obtained. The current operating result parameters are compared with the process design parameters of the same operating condition to obtain the current difference value of the current operating condition. If the current difference value does not meet the design limit value, the adjustment strategy of the automatic control program of the gas equipment system in the current operating condition is analyzed to obtain so that the difference value meets the design limit value.

[0042] Based on the operation result parameters of the dynamic simulation model of the different typical operation conditions, multiple adjustment strategies of the automatic control program of the gas equipment system are analyzed and obtained.

[0043] Among them, Figure 4 The figure shows a set of gas pressure operation result parameters of the dynamic simulation model of the gas equipment system. Figure 4 The first schematic diagram of the gas pressure operation result parameters shows that the gas pressure is insufficient, the second schematic diagram of the gas pressure operation result parameters shows that the gas pressure fluctuates greatly, and the third schematic diagram of the gas pressure operation result parameters shows that the gas pressure is relatively stable.

[0044] Among them, the adjustment strategy of the automatic control program of the gas equipment system in the current operating condition involves one adjustment or multiple combined adjustments of the gas supply pressure and temperature correlation control strategies output by the gas equipment system, including the variable frequency control strategy of the LNG deep well pump or submersible pump motor, the LNG deep well pump or submersible pump bypass control valve control strategy, the variable frequency control strategy of the gas compressor motor, the gas compressor bypass control valve control strategy, the variable frequency control strategy of the high-pressure LNG reciprocating pump motor, the high-pressure LNG reciprocating pump bypass control valve control strategy, the low-pressure buffer tank pressure regulating valve control strategy and the LNG evaporator heating or cooling medium ethylene glycol water temperature control valve control strategy.

[0045] Wherein, the associated control strategy includes but is not limited to the PID control strategy. The adjustment of the associated control strategy includes the adjustment of the associated control parameters of the associated control strategy. If the associated control strategy adopts the PID control strategy, it includes the adjustment of the proportional, differential and integral associated control parameters of the PID control strategy.

[0046] Adjust the automation control program of the gas equipment system according to the optimal adjustment strategy.

[0047] Based on the multiple adjustment strategies, calculation iterations are performed through a linear programming algorithm until an optimal adjustment strategy for the automation control program is found.

[0048] Step 6: Based on the optimal adjustment strategy of the automatic control program of the gas equipment system, adjust the automatic control program of the gas equipment system.

[0049] The adjustment of the automation control program includes the adjustment of the associated control parameters of the associated control strategy.

[0050] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A dynamic simulation method for a gas equipment system based on digital twin technology, characterized in that: include: Obtain typical operating conditions of the gas equipment system, obtain process design parameters of system equipment components of the gas equipment system under typical operating conditions, establish a static simulation model of the gas equipment system based on digital twin technology, and input the obtained process design parameters of the system equipment components into the static simulation model of the gas equipment system; Establish a connection between the static simulation model of the gas equipment system and the database of the gas equipment system and the signal of the automation control program to create a dynamic simulation model of the gas equipment system; Load the gas equipment system automation control program onto the virtual simulator, and exchange real-time data between the virtual simulator and the dynamic simulation model of the gas equipment system to form a closed-loop dynamic simulation platform; Inputting the initial operating conditions of several typical operating conditions of the gas equipment system into the dynamic simulation model of the gas equipment system, running the automatic control program in the closed-loop dynamic simulation platform, and generating operating result parameter information of the gas equipment system corresponding to several typical operating conditions; Generate adjustment strategy information according to the operation result parameter information of the typical operation condition, substitute the adjustment strategy information into the dynamic simulation model of the gas equipment system, and obtain the optimal adjustment strategy of the gas equipment system; Adjust the automation control program of the gas equipment system according to the optimal adjustment strategy.

2. The dynamic simulation method of a gas equipment system based on digital twin technology according to claim 1 is characterized in that: The gas equipment system includes a dual-fuel boiler, a first dual-fuel power generation engine, a second dual-fuel power generation engine, a third dual-fuel power generation engine, a high-pressure dual-fuel main propulsion engine, a first main gas valve, a second main gas valve, a third main gas valve, a low-temperature gas buffer tank, a pressure regulating valve, a gas compressor, a compressor bypass control valve, a low-pressure LNG evaporator, a high-pressure gas buffer tank, a high-pressure LNG evaporator, a high-pressure LNG reciprocating pump, a reciprocating pump bypass control valve, a low-pressure pump bypass control valve, an LNG storage tank, an LNG submersible pump and an LNG deep well pump. The LNG storage tank is provided with an LNG deep well pump and an LNG submersible pump. The LNG storage tank is connected to the gas compressor through a pipeline. The gas compressor is connected to the gas cooler. A bypass is provided on the side of the gas compressor and the gas cooler, and a compressor bypass control valve is provided on the bypass. , one end of the pressure regulating valve is connected to the gas cooler, the other end of the pressure regulating valve is connected to the low-pressure gas buffer tank, the low-pressure gas buffer tank is connected to the third main gas valve, and the third main gas valve is connected to the dual-fuel boiler; the LNG deep well pump is simultaneously connected to the low-pressure pump bypass control valve, the high-pressure LNG reciprocating pump and the low-pressure LNG evaporator, the low-pressure LNG evaporator is connected to the low-pressure gas buffer tank, the low-pressure gas buffer tank is connected to the second main gas valve, and the second main gas valve is simultaneously connected to the first dual-fuel power generation engine, the second dual-fuel power generation engine and the third dual-fuel power generation engine; the high-pressure LNG reciprocating pump is connected to the high-pressure LNG evaporator, a bypass is provided on the side of the high-pressure LNG reciprocating pump, and a reciprocating pump bypass control valve is provided on the bypass, one end of the high-pressure gas buffer tank is connected to the high-pressure LNG evaporator, the other end of the high-pressure gas buffer tank is connected to the first gas valve, and the first main gas valve is connected to the high-pressure dual-fuel main propulsion engine.

3. The dynamic simulation method of the gas equipment system based on digital twin technology according to claim 2 is characterized in that: Typical operating conditions include: The first typical operating condition: the stable operating condition of high-pressure gas at the maximum flow rate and the instantaneous switching from the stable operating condition of high-pressure gas at the maximum flow rate to the emergency gas cut-off condition; The second typical operating condition: the stable operating condition of low-pressure gas at the maximum flow rate and the instantaneous switching from the stable operating condition of low-pressure gas at the maximum flow rate to the emergency gas cut-off condition; The third typical operating condition: a stable operating condition with high-pressure and low-pressure gas supplied simultaneously at the maximum flow rate and an instantaneous switch from a stable operating condition with high-pressure and low-pressure gas supplied simultaneously at the maximum flow rate to an emergency gas cut-off condition; The fourth typical operating condition: stable operation of high-pressure and low-pressure gas supply at the maximum flow rate is switched to stable operation of high-pressure and low-pressure gas supply at the minimum flow rate; The specific process of the first typical operating condition includes: Start the LNG deep well pump or submersible pump, and use the LNG transported by the LNG deep well pump or submersible pump to precool the high-pressure LNG reciprocating pump. When the temperature of the high-pressure LNG reciprocating pump is precooled to below -130°C, start the high-pressure LNG reciprocating pump, switch the high-pressure dual-fuel main propulsion engine to gas operation, open the main gas valve of the high-pressure dual-fuel main propulsion engine, load the high-pressure dual-fuel main propulsion engine to 100% load, and operate the high-pressure gas stably at the maximum flow rate; then the high-pressure dual-fuel main propulsion engine is instantly cut off from gas due to a fault, and switched to fuel mode operation; The specific process of the second typical operating condition includes: Start the LNG deep well pump or submersible pump, start the gas compressor, switch the three low-pressure dual-fuel generator engines and one low-pressure dual-fuel boiler from fuel oil mode to gas operation one by one, open the main gas valve of the generator engine and the main gas valve of the boiler, adjust the load of the three generator engines to 70% load, and adjust the load of one boiler to 100% load, and the low-pressure gas runs stably at the maximum flow rate; then the three generator engines and one boiler are cut off from gas at the same time due to a fault, and the three generator engines are switched to fuel oil mode, and one boiler stops running; The specific process of the third typical operating condition includes: Start the LNG deep well pump or submersible pump, start the gas compressor, switch two low-pressure dual-fuel generator engines and one low-pressure dual-fuel boiler from fuel oil mode to gas operation one by one, open the main gas valve of the generator engine and the main gas valve of the boiler, adjust the gas operation load of the two generator engines to 55% load, and adjust the gas operation load of one boiler to 45% load, use the LNG transported by the LNG deep well pump or submersible pump to precool the high-pressure LNG reciprocating pump, wait for the high-pressure LNG reciprocating pump to be precooled to a temperature below -130°C, start the high-pressure LNG reciprocating pump, switch the high-pressure dual-fuel main propulsion engine from fuel oil mode to gas operation, open the main gas valve of the high-pressure dual-fuel main propulsion engine, and load the high-pressure dual-fuel main propulsion engine to 100% load. At this time, the high-pressure and low-pressure gas are simultaneously supplied and run stably at the maximum flow rate; then the high-pressure dual-fuel main propulsion engine, two generator engines and one boiler are cut off from gas at the same time due to a fault, and the high-pressure dual-fuel main propulsion engine and two generator engines are changed to fuel oil mode, and one boiler stops running; The specific process of the fourth typical operating condition includes: Start the LNG deep well pump or submersible pump, start the gas compressor, switch two low-pressure dual-fuel generator engines and one low-pressure dual-fuel boiler from fuel mode to gas operation one by one, open the main gas valve of the generator engine and the main gas valve of the boiler, adjust the gas operation load of the two generator engines to 55% load, and adjust the gas operation load of one boiler to 45% load. Use the LNG transported by the LNG deep well pump or submersible pump to precool the high-pressure LNG reciprocating pump. When the temperature of the high-pressure LNG reciprocating pump is precooled to below -130℃, start the high-pressure LNG reciprocating pump, and the high-pressure dual-fuel main propulsion engine is switched from The fuel mode is switched to gas operation, the main gas valve of the high-pressure dual-fuel main propulsion engine is opened, and the load of the high-pressure dual-fuel main propulsion engine is loaded to 100% load. At this time, high-pressure and low-pressure gas are supplied simultaneously and operate stably at the maximum flow rate; then, a generator engine and a boiler are cut off from gas at the same time due to a fault. The generator engine is switched to fuel mode operation, and the boiler stops running. The gas operating load of the high-pressure dual-fuel main propulsion engine is adjusted to 10% load, and the gas operating load of the other generator engine is adjusted to 40%. At this time, high-pressure and low-pressure gas are supplied simultaneously and operate stably at the minimum flow rate.

4. The dynamic simulation method of a gas equipment system based on digital twin technology according to claim 3 is characterized in that: The establishment of a static simulation model of a gas equipment system based on digital twin technology includes: The process design parameters of each equipment component in the gas equipment system are obtained respectively, and the physical relationship sub-model of the gas equipment system and each equipment component is constructed, and the physical relationship sub-model includes: the physical relationship sub-model of LNG storage tank pressure and temperature; the physical relationship sub-model of LNG deep well pump or submersible pump flow and head; the physical relationship sub-model of gas compressor flow, exhaust pressure and temperature; the physical relationship sub-model of high-pressure LNG reciprocating pump flow and head; the physical relationship sub-model of low-pressure LNG evaporator liquid and gas two-phase flow conversion; the physical relationship sub-model of high-pressure LNG evaporator liquid and gas two-phase flow conversion; the physical relationship sub-model of gas cooler gas heat exchange; the physical relationship sub-model of LNG liquid and gas pipeline flow and pressure loss; the physical relationship sub-model of gas-using equipment load setting; Based on the physical relationship sub-models of the gas equipment system and each equipment component, a multi-physical quantity static simulation sub-model of each component is constructed in one-to-one correspondence with the physical relationship sub-model; According to the physical process flow and numerical calculation relationship between each system equipment component of the gas equipment system, the static simulation sub-models of each system equipment component of the gas equipment system are connected to create a complete static simulation model of the gas equipment system.

5. The dynamic simulation method of a gas equipment system based on digital twin technology according to claim 4 is characterized in that: The initial operating conditions are the initial set values ​​for the operation of the dynamic simulation model of the gas equipment system, including the initial liquid level height, initial pressure, initial temperature, external ambient temperature, composition of the LNG storage tank, the composition ratio of water glycol as the heat exchange medium of the LNG evaporator, the initial state of the gas equipment system and the gas-using equipment, and the load setting of the gas-using equipment.

6. The dynamic simulation method of a gas equipment system based on digital twin technology according to claim 5 is characterized in that: The step of generating adjustment strategy information according to the operation result parameter information of the typical operation condition includes: Based on the dynamic simulation model of the gas equipment system, according to the workflow of one of the selected typical operating conditions, initial operating conditions are input into the dynamic simulation model of the gas equipment system, the automatic control program of the gas equipment system is run through the PLC virtual simulator, and real-time data is exchanged with the dynamic simulation model of the gas equipment system, the dynamic simulation model of the gas equipment system is updated, and current operating result parameters of the dynamic simulation model of the gas equipment system in the current operating condition are obtained; Compare the current operating result parameters with the process design parameters of the same operating condition to obtain the current difference value of the current operating condition. If the current difference value does not meet the design limit value, analyze and obtain the adjustment strategy of the automatic control program of the gas equipment system under the current operating condition; Based on the operation result parameters of the dynamic simulation model of the different typical operation conditions, multiple adjustment strategies of the automatic control program of the gas equipment system are analyzed and generated.

7. The dynamic simulation method of a gas equipment system based on digital twin technology according to claim 6 is characterized in that: The operating result parameters of the dynamic simulation model of the gas equipment system include the operating result parameters of the pressure and temperature of the gas supply from the gas equipment system to the gas-consuming equipment changing with time; the steady-state value and instantaneous change value of the gas supply pressure and temperature are obtained from the operating result parameters of the pressure and temperature changing with time.

8. The dynamic simulation method of a gas equipment system based on digital twin technology according to claim 7 is characterized in that: The optimal adjustment strategy of the automatic control program of the gas equipment system includes performing a linear programming algorithm of the simplex method based on the multiple adjustment strategies, and iterating calculations until the optimal adjustment strategy of the automatic control program is found.

9. The dynamic simulation method of a gas equipment system based on digital twin technology according to claim 8 is characterized in that: The closed-loop dynamic simulation platform includes loading the automation control program of the gas equipment system into the PLC virtual simulator, simulating the PLC controller through the PLC virtual simulator to run the automation control program of the gas equipment system, and performing real-time data exchange with the dynamic simulation model of the gas equipment system to form a closed-loop dynamic simulation platform; The closed-loop dynamic simulation platform is used to simulate the dynamic changes in temperature and pressure of liquid and gas phase LNG in a gas equipment system over time.

10. The dynamic simulation method of a gas equipment system based on digital twin technology according to claim 9 is characterized in that: The establishment process of the dynamic simulation model of the gas equipment system specifically includes: By establishing a signal and database connection between the static simulation model of the gas equipment system and the automatic control program of the gas equipment system; Input signals and data required by the automatic control program of the gas equipment system are input into the static simulation model of the gas equipment system; or output signals and data required by the automatic control program of the gas equipment system are output from the static simulation model of the gas equipment system; Form a dynamic simulation model of the gas equipment system; The specific process of establishing a signal and database connection between the static simulation model of the gas equipment system and the automatic control program of the gas equipment system includes: According to the interface information of the automatic control program of the gas equipment system, the static simulation model of the gas equipment system is configured with input and output signals; adding the output signal of the automatic control program of the gas equipment system as the input signal of the static simulation model of the gas equipment system to the static simulation model of the gas equipment system; Similarly, the input signal required by the gas equipment system automation control program is the signal output calculated from the static simulation model of the gas equipment system. It needs to be extracted from the static simulation model of the gas equipment system according to the position and feedback information of the sensors in the actual gas equipment system and fed back to the gas equipment system automation control program as the input signal.

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