An integrated dynamic simulation method, system, device and medium for a comprehensive energy system

Abstract

The present application provides an integrated dynamic simulation method, system, equipment, and medium for a comprehensive energy system, which relates to the field of energy utilization technology. Based on a dynamic two-port model of an energy network, a transfer matrix and a state equation are configured to characterize the dynamic transmission process corresponding to the parameter characteristics of the gas network pipeline and the parameter characteristics of the heat network pipeline; a dynamic simulation model of the equipment is constructed; based on the nonlinear finite difference method, a comprehensive energy system model with a dynamic transmission process and a dynamic simulation model of the equipment is constructed, and the constructed comprehensive energy system model is dynamically simulated. The transient behavior of the gas network turbulence and the phase change of the heat pump working fluid is captured by nonlinear partial differential equations to achieve dynamic simulation and save the simulation results. The present application can capture transient processes and support dynamic interactive simulation of gas-heat-grid networks; it has a rich set of dynamically coupled devices, and the present application has excellent scalability and adaptability. It can be connected to new equipment models or external control strategies and is suitable for a variety of application scenarios.

Description

Technical Field

[0001] The present application relates to the field of energy utilization technology, and specifically to an integrated dynamic simulation method, system, equipment and medium for a comprehensive energy system. Background Art

[0002] As an efficient energy utilization system, the Integrated Energy System (IES) achieves comprehensive energy utilization by organically combining different energy forms, effectively improving energy system efficiency and reducing energy consumption, becoming a key path for energy transformation and upgrading. Modeling and simulation technologies play a vital role in the planning, design, and construction of IES. IES modeling is primarily divided into steady-state modeling and dynamic modeling. While steady-state modeling is relatively mature, dynamic modeling still faces numerous technical challenges. First, IES involves multiple disciplines and fields, and its dynamic modeling requires addressing the key issues of multi-scale modeling and collaborative optimization. Furthermore, complex energy supply and demand scenarios place higher demands on the versatility and adaptability of modeling and data processing.

[0003] IES can integrate multiple energy sources within a region, including coal, oil, natural gas, electricity, and thermal energy, for coordinated management and interactive response. IES not only significantly reduces fossil energy consumption and lowers system carbon emissions, but also optimizes the energy mix, improves overall energy efficiency, and effectively enhances energy system resilience. It provides crucial support for renewable energy output tracking and volatility mitigation, offering significant advantages over traditional energy systems. Its modeling can help decision-makers formulate sustainable energy policies, achieve coordinated planning and optimized operation across diverse energy subsystems, and simultaneously optimize system operation and efficiency, thereby reducing environmental pollution and carbon emissions.

[0004] The development of IES relies on the support of an integrated energy simulation and planning platform. Selecting the right platform is crucial for the design, investment, planning, and development of integrated energy projects. Three typical and commonly used simulation platforms are currently being compared and analyzed: COMPOSE (compare options for sustainable energy), developed by Aalborg University in Denmark in 2008, supports the study of electricity, heating, and cooling systems; HOMER (hybrid optimization model for electric renewables), developed by the U.S. National Renewable Energy Laboratory, is software that performs system optimization and sensitivity analysis. Its simulations have a time resolution of minutes and can span multiple years; and RETScreen Expert, released in September 2016, is free clean energy management software developed by the Canadian government. This software comprehensively identifies, evaluates, and optimizes the technical and financial feasibility of potential renewable energy and energy efficiency projects. It also measures and verifies the actual performance of equipment and facilities, enabling the development of energy conservation plans. The shortcomings of existing solutions are: COMPOSE only focuses on the cogeneration of electric boilers and compression heat pumps for thermal systems; the complexity of HOMER calculations determines that the platform is only suitable for microgrid-scale planning; RETScreen Expert does not provide the function of optimizing design parameters.

[0005] To sum up, it can be understood that although most of the existing software platforms have their own advantages, they are unable to well realize the joint simulation between the various energy subsystems of the integrated energy system. At the same time, there are some shortcomings. First, multi-energy flow coupling equipment involves dynamic interactions of multiple physical fields such as electricity, heat, and chemistry. Its model needs to integrate dynamic processes of different time scales (such as second-level electrical response and hour-level thermal diffusion), resulting in high equation dimensions and difficulty in obtaining the results required by the demander; secondly, the accurate identification of equipment dynamic parameters and insufficient adaptability to multiple working conditions limit the practicality of the model; in addition, traditional energy flow simulation tools (such as energy lumped models) are difficult to be compatible with highly dynamic nonlinear equations. Summary of the Invention

[0006] The present invention provides an integrated dynamic simulation method for a comprehensive energy system. The method integrates two types of high-precision models and places great emphasis on user-friendliness and engineering practicality. Through a modular architecture and dynamic models, it realizes a fully dynamic electrical-gas-thermal coupled simulation of the network-device system, and supports solution algorithm selection and parameter configuration to meet usage requirements.

[0007] Methods include:

[0008] Based on the dynamic two-port model of the energy network, the transfer matrix and state equation are configured to characterize the dynamic transmission process corresponding to the parameter characteristics of the gas network pipeline and the heat network pipeline.

[0009] Build a dynamic simulation model of the equipment and couple the P2G electricity-gas conversion time delay, the heat pump working fluid phase change thermodynamic transient, and the CHP thermoelectric power dynamic decoupling characteristics;

[0010] Based on the nonlinear finite difference method, a comprehensive energy system model with a dynamic transmission process and equipment dynamic simulation model is built. The built comprehensive energy system model is dynamically simulated, and the transient behavior of gas network turbulence and heat pump working fluid phase change is captured with nonlinear partial differential equations to achieve dynamic simulation and save the simulation results.

[0011] It should be further explained that the dynamic transmission process of the gas network pipeline is

[0012]

[0013]

[0014] in, is the density of natural gas, is the natural gas transmission speed, For pressure, is the diameter, is the friction coefficient, is the acceleration due to gravity, is the pipe inclination angle; the subscript in the parameter For pipelines The entry parameter, subscript For pipelines Export parameter, superscript Indicates the parameter of the previous moment, with a superscript Represents the parameter at the current moment.

[0015] It should be further explained that in this method, based on the dynamic two-port model of the energy network, the known input parameters are the input and output pressure and flow at the previous moment, and the output parameters to be calculated are the input and output pressure and flow at the current moment. The intermediate conversion relationship is extracted from the parameter characteristics of the gas network pipeline, and the modeling is completed in the Simulink environment to obtain the two-port dynamic model of the gas network.

[0016] It should be further explained that the heat medium transmission characteristics in the heat network pipeline are expressed as:

[0017]

[0018]

[0019]

[0020] Among them, the variables are defined as within the heat network pipeline, is the density of water, For pressure, For traffic, is the mass flow rate base value corresponding to the velocity base value, is the cross-sectional area, is the acceleration due to gravity, is the pipe inclination angle, is the specific heat of water, is the diameter, is the friction coefficient, is the heat dissipation coefficient, is the pipe temperature, is the flow time of water in the heat network pipe, is the flow distance of water in the pipe;

[0021] Define the flow direction as In the positive direction, the discrete nodes are numbered , the time step is , the spatial step length is , in the pipeline and time layer At , the equation is discretized to get:

[0022]

[0023]

[0024]

[0025] Among them, the subscript For pipelines The entry parameter, subscript For pipelines Export parameter, superscript Indicates the parameter of the previous moment, with a superscript Represents the parameter at the current moment.

[0026] It should be further explained that in the step-coupled P2G electric-to-gas conversion delay, the P2G dynamic model transfer function is defined as:

[0027]

[0028] in, 、 are the flow rates of gas flowing into and out of the volume module, is the reaction ratio of the inflowing gas, is the reactor volume, is the outlet flow rate under rated conditions, is the reactor pressure under rated conditions, s is the Laplace transform variable, p is the pressure, is the representation of the output in the Laplace domain, is the representation of the input in the Laplace domain.

[0029] It should be further explained that in the step of building the equipment dynamic simulation model, in the heat pump working fluid phase change thermodynamic transient, the supply and return water temperatures are defined to satisfy the following equations:

[0030]

[0031]

[0032] in, Indicates the pipeline flow rate during the heating process, and Represents the supply water temperature and return water temperature respectively. and They represent the specific heat capacity and density of the hot water in the tank, Indicates the capacity of the hot water tank. Indicates the heat dissipation of the water tank. To lose floor surface temperature, Indicates the heat generated by the heat pump. For a heat pump system, the heat generated by its work is proportional to the power of its compressor. , heat pump performance coefficient Related, expressed as follows:

[0033] .

[0034] It should be further explained that in the step of constructing the dynamic decoupling characteristics of the CHP thermoelectric power of the equipment dynamic simulation model, the CHP is divided into four parts: compressor, combustion chamber, turbine, and heat exchanger for modeling. The main formulas of each part are as follows:

[0035]

[0036] The variable definition range in the formula is within the compressor module. is the required power; is the inlet pressure; is the outlet pressure; is the efficiency; the polynomial index can be expressed as ; is the export flow; is the module equivalent volume; is the average gas constant of the fuel gas; is the outlet temperature;

[0037]

[0038] The variable definition range in the formula is within the combustion chamber module. is the combustion chamber time constant; is the outlet temperature; For combustion efficiency; is the inlet air enthalpy; is the inlet natural gas enthalpy; is the outlet gas enthalpy; is the inlet natural gas mass flow rate; is the outlet gas mass flow rate; is the constant pressure specific heat capacity of the outlet gas; is the net specific energy of natural gas; is the combustion chamber gas quality; is the air mass flow rate at the combustion chamber inlet;

[0039] The output is connected to the turbine input as follows:

[0040]

[0041]

[0042] Where: is the turbine outlet temperature; is the turbine inlet temperature; is the turbine pressure ratio; is the turbine efficiency; Power consumed by the turbine; is the turbine equivalent flow rate; , is the gas adiabatic index, is the constant pressure specific heat capacity of the combustion chamber outlet gas.

[0043] The present application also provides an integrated dynamic simulation system for a comprehensive energy system, the system comprising:

[0044] The parameter feature configuration module is used to use the energy network dynamic two-port model to configure the transfer matrix and state equation to characterize the dynamic transmission process corresponding to the parameter characteristics of the gas network pipeline and the heat network pipeline;

[0045] The model building module is used to build a dynamic simulation model of the equipment and couple the P2G electric-gas conversion time delay, the heat pump working fluid phase change thermodynamic transient and the CHP thermoelectric power dynamic decoupling characteristics;

[0046] The simulation processing module is used to combine the nonlinear finite difference method to build an integrated energy system model with a dynamic transmission process and equipment dynamic simulation model, perform dynamic simulation on the built integrated energy system model, and use nonlinear partial differential equations to capture the transient behavior of gas network turbulence and heat pump working fluid phase change to achieve dynamic simulation and save the simulation results.

[0047] According to another embodiment of the present application, an electronic device is provided, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the processor implements the steps of the integrated dynamic simulation system of the comprehensive energy system when executing the program.

[0048] According to another embodiment of the present application, a storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of the integrated dynamic simulation system of the comprehensive energy system are implemented.

[0049] It can be seen from the above technical solutions that the present invention has the following advantages:

[0050] The integrated dynamic simulation method for a comprehensive energy system provided in this application is based on a dynamic two-port model of the energy network. It uses the characteristic line method to construct a time-domain two-port model of the gas network to reflect the input-output relationship of the gas network. It describes the dynamic transmission characteristics of the gas network pipeline to more accurately characterize the dynamic behavior of the gas network. Compared with related technologies, it is difficult to accurately characterize the dynamic characteristics of the gas network and the heat network at the same time. However, the use of a dynamic two-port model of the energy network, combined with the transfer matrix and state equation, can more comprehensively and accurately reflect the dynamic transmission process of the gas network and the heat network.

[0051] When constructing a dynamic device simulation model, this application considers the time lag caused by factors such as chemical reaction kinetics and catalyst activity during the electricity-to-gas conversion process for P2G devices. For heat pumps, the phase change process of the working fluid is modeled. For CHPs, a dynamic decoupling model for thermoelectric power is established, taking into account the generation, distribution, and mutual influence of heat and electricity during the combined heat and power process to achieve dynamic decoupling control of thermoelectric power. This model can simultaneously consider multiple complex factors and accurately model the dynamic characteristics of the device. When building an integrated energy system model based on the nonlinear finite difference method, the gas network, heat network, and device dynamic simulation models are integrated. Through discretization, continuous partial differential equations are converted into a system of algebraic equations to capture transient behaviors such as gas network turbulence and heat pump working fluid phase change. During the simulation process, an appropriate numerical solution algorithm is used to solve the nonlinear equations. The simulation time is gradually advanced according to the set simulation step size and convergence accuracy to obtain the system's dynamic response, and the simulation results are saved as data files or graphical representations. This model can effectively handle the complex dynamic behavior of integrated energy systems and achieve high-precision dynamic simulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the technical solution of the present invention, the following is a brief introduction to the drawings required for the description. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0053] Figure 1 This is a flow chart of the integrated dynamic simulation method for the comprehensive energy system;

[0054] Figure 2 Schematic diagram of the one-key parameter modification interface;

[0055] Figure 3 Schematic diagram of an electronic device. DETAILED DESCRIPTION

[0056] The integrated dynamic simulation method for a comprehensive energy system involved in this application is primarily designed to address the problem in related technologies where multi-energy flow coupled equipment involves dynamic interactions among multiple physical fields, such as electricity, heat, and chemistry. Its model must integrate dynamic processes at different time scales, resulting in high-dimensional equations and complex solutions. It also aims to address the drawbacks of the precise identification of equipment dynamic parameters and insufficient adaptability to multiple operating conditions, which limits the practicality of the model and makes it difficult to accommodate highly dynamic nonlinear equations.

[0057] The integrated dynamic simulation method for an integrated energy system proposed in this application is an integrated energy integrated dynamic simulation software that integrates high-precision models and focuses on user-friendliness and engineering practicality. Through a modular architecture and dynamic models, it achieves full dynamic coupled simulation of electricity, gas, and heat. Based on the two-port model of the energy network, the characteristics of the gas and heat networks are accurately characterized. The coupled device model constructed on the Simulink platform covers a variety of dynamic characteristics. The software is easy to operate, and users can drag and drop modules to build models and simulate them, facilitating the subsequent development of new features.

[0058] This application proposes a dynamic two-port network model for gas and heat network pipelines, aiming to systematically characterize the dynamic response process of energy transmission within the pipeline through transfer matrices and state variable equations. Compared with traditional lumped parameter models, this model dynamically associates physical quantities (such as air pressure, flow, temperature, and heat flow) at the pipeline inlet and outlet through a two-port network structure, and embeds energy conservation and transmission delay characteristics, thereby more accurately describing nonlinear dynamic behaviors such as gas network transmission characteristics and heat network thermal inertia. In addition, from the user's perspective, this application converts complex dynamic mechanism equations into two-port modeling. Users do not need to pay attention to the complex internal logical structure and only need to change external parameters such as input according to their needs. To improve the user's selectivity and convenience when using the integrated dynamic simulation software developed later in this embodiment, this application provides three methods in the modeling and simulation process: linear finite difference method, nonlinear finite difference method, and holomorphic embedding method.

[0059] The following describes in detail the specific steps of the integrated dynamic simulation method for a comprehensive energy system. Specific details such as specific system structures and technologies are provided for illustrative purposes, not for limitation, to facilitate a thorough understanding of the embodiments of this application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details.

[0060] It should be understood that when used in this specification, the term "comprising" indicates the presence of the described features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or their collections. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized.

[0061] It should be understood that the "one or more" mentioned in this application refers to one, two or more, and the "multiple" mentioned in this application refers to two or more. In the description of this application, unless otherwise specified, " / " means or, for example, A / B can mean A or B. The "and / or" in this article is only a way to describe the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone.

[0062] The phrases "one embodiment" or "some embodiments" described in this application mean that the particular features, structures, or characteristics described in the embodiment are included in one or more embodiments of the application. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in other embodiments," etc. that appear in different places in this application do not necessarily refer to the same embodiment, but rather mean "one or more but not all embodiments," unless otherwise specifically emphasized.

[0063] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 making creative efforts are within the scope of protection of the present invention.

[0064] See also Figure 1 FIG2 is a flow chart of a method for integrated dynamic simulation of a comprehensive energy system in a specific embodiment, the method comprising:

[0065] S101: Based on the dynamic two-port model of the energy network, configure the transfer matrix and state equation to characterize the dynamic transmission process corresponding to the parameter characteristics of the gas network pipeline and the parameter characteristics of the heat network pipeline.

[0066] In some embodiments, a dynamic two-port network model is constructed to characterize the dynamic transmission characteristics of the gas and heat networks through transfer matrices and state equations. Specifically, the transfer matrix of the gas network pipeline must include dynamic parameters such as the pressure wave propagation velocity and the pipeline friction resistance coefficient. The state equation is based on the mass conservation and momentum conservation equations, introducing a time delay term to simulate the compression and expansion process of the gas in the pipeline. The transfer matrix of the heat network pipeline must consider thermal conductivity, specific heat capacity, and fluid flow characteristics. The state equation couples the heat conduction equation with the convective heat transfer equation, and describes the dynamic coupling relationship between the temperature field and the flow velocity field through a set of partial differential equations.

[0067] Compared to the steady-state or quasi-steady-state models commonly used in existing technologies, this method captures the transient characteristics of energy flow transmission, such as pressure fluctuations and temperature diffusion, through a dynamic two-port model, thereby improving simulation accuracy. By extending dynamic modeling methods for power systems (such as transfer functions) to multi-energy coupled systems and achieving a unified solution for cross-scale dynamic processes through nonlinear finite difference methods, this method overcomes the limitations of traditional software that focuses solely on a single energy subsystem.

[0068] Optionally, for gas network pipelines, the state equation will consider the effects of factors such as gas compressibility and friction on gas flow; for heat network pipelines, the effects of factors such as heat conduction and heat convection on heat transfer will be considered.

[0069] S102: Construct a dynamic simulation model of the equipment and couple the P2G electricity-gas conversion time delay, the heat pump working fluid phase change thermodynamic transient, and the CHP thermoelectric power dynamic decoupling characteristics.

[0070] In some embodiments, a dynamic simulation model of the device is constructed and multi-physics interaction characteristics are coupled. Specifically, for P2G devices, a time-lag model of electricity-gas conversion is established, and the hysteresis effect of the chemical reaction of electrolysis of water to produce hydrogen is simulated by delaying differential equations; for heat pumps, a thermodynamic transient model of working fluid phase change is introduced, and the latent heat exchange equation and the dynamic change of working fluid physical parameters are combined to describe the transient heat transfer process of the evaporator and condenser; for CHP, a dynamic decoupling model of thermoelectric power is constructed, and the dynamic response of the mechanical power of the gas turbine and the thermal power of the waste heat boiler is separated to achieve real-time power distribution control of cogeneration. RETScreen Expert in existing methods ignores the dynamic characteristics of the device or only provides simplified static parameters. This method solves the problems of difficult identification of dynamic parameters of the device and poor adaptability to multiple working conditions by coupling multi-time-scale dynamic equations. It integrates high-precision thermodynamic models with power electronics dynamic models and realizes seamless integration across energy subsystems through modular interfaces.

[0071] S103: Based on the nonlinear finite difference method, a comprehensive energy system model with a dynamic transmission process and equipment dynamic simulation model is constructed. Dynamic simulation is performed on the constructed comprehensive energy system model. Nonlinear partial differential equations are used to capture the transient behavior of gas network turbulence and heat pump working fluid phase change to achieve dynamic simulation and save the simulation results.

[0072] In some embodiments, based on the nonlinear finite difference method, the previously constructed gas network and heat network dynamic transmission models and equipment dynamic simulation models are integrated to build a comprehensive energy system model. The nonlinear finite difference method discretizes the space and time of the system, and uses nonlinear partial differential equations to describe and capture highly nonlinear fluid motion such as gas network turbulence and complex transient behaviors involving multiphase changes such as heat pump working fluid phase change. During the dynamic simulation process, the equations are gradually solved according to the set time step and calculation rules to obtain the state parameters of the system at different times, such as pressure, temperature, flow, etc. at each node, and these simulation results are saved for subsequent analysis.

[0073] This step achieves accurate simulation of the dynamic process of the integrated energy system by adopting the nonlinear finite difference method combined with solving nonlinear partial differential equations.

[0074] The following example uses a comprehensive energy system for a certain industrial park. This system includes a natural gas supply network, a hot water supply network, and various electricity-to-gas-to-heat conversion devices, such as P2G equipment, heat pumps, and CHP units. To perform an integrated dynamic simulation of this system, step S101 is first executed to construct dynamic transmission models for the gas and heat networks based on the dynamic two-port model of the energy network. For the gas network, a time-domain two-port model is established using the characteristic line method. Factors such as the compressibility of natural gas and friction losses in the pipeline are considered, and the transfer matrix and state equations are configured to accurately characterize the dynamic transmission process of natural gas in the pipeline. For the heat network, a similar modeling approach is used, taking into account factors such as the flow characteristics of hot water and heat losses to establish a dynamic transmission model for the heat network.

[0075] Next, execute step S102 to construct a dynamic simulation model for the equipment. For P2G equipment, detailed modeling is performed to account for time lags caused by factors such as chemical reaction kinetics and catalyst activity during the electricity-to-gas conversion process. For heat pumps, the phase change process of the working fluid is modeled, including the latent heat of phase change, the phase change temperature range, and the heat transfer rate. For CHP units, a dynamic decoupling model for thermal power is established, accounting for the generation, distribution, and mutual influence of heat and electricity during the combined heat and power process.

[0076] Finally, step S103 is executed to integrate the dynamic simulation models of the gas network, heat network, and equipment based on the nonlinear finite difference method to build a comprehensive energy system model. Through discretization, the continuous partial differential equations are converted into a set of algebraic equations, and numerical solution algorithms such as the Newton-Raphson method are used to solve them. During the simulation process, the appropriate simulation step size and convergence accuracy are set, the simulation time is gradually advanced, the dynamic response of the system is obtained, and the simulation results are saved for subsequent analysis and optimization. Through this integrated dynamic simulation method, the dynamic operating characteristics of the park's comprehensive energy system can be fully and accurately reflected, providing technical support for the planning, operation, and control of the system.

[0077] Building on the above-mentioned embodiments, to further enhance the reliability of the integrated dynamic simulation method for integrated energy systems provided in these embodiments, a more specific implementation is provided below. From a user's perspective, this embodiment converts complex dynamic mechanism equations into a two-port model. Users do not need to worry about the complex internal logic structure; they only need to modify external parameters such as inputs as needed. To enhance user convenience and selectivity when using the integrated dynamic simulation software developed later in this embodiment, this embodiment provides three methods for modeling and simulation: linear finite difference method, nonlinear finite difference method, and holomorphic embedding method. This embodiment primarily introduces dynamic models using the nonlinear finite difference method. This method extends the traditional finite difference method to handle nonlinear partial differential equations and capture the transient behavior of nonlinear effects (such as gas grid turbulence and heat pump working fluid phase change). This method achieves high simulation accuracy while balancing computational efficiency and cost, making it suitable for a wide range of users.

[0078] In this embodiment, the natural gas network relies on pressure to drive the working fluid flow, thereby achieving efficient energy transmission. Under isothermal conditions, the transmission behavior of gas in the pipeline can usually be described by the continuity equation and the momentum equation. If gas pressure and mass flow rate are selected as the key parameters to describe the system state, then the transmission characteristics of natural gas in the pipeline can be accurately expressed by a set of partial differential equations, including the mass conservation equation (1) and the momentum conservation equation (2).

[0079] (1)

[0080] (2)

[0081] Among them, the variables are defined in the gas network pipeline. is the density of natural gas, is the flow time of natural gas, is the natural gas transmission speed, is the flow distance of natural gas, For pressure, is the diameter, is the friction coefficient, is the acceleration due to gravity, is the pipe inclination angle.

[0082] This embodiment discretizes the original equation, uses the first-order forward difference for the time term and displays it in a display format; and uses the first-order central difference for the space term. Discretize axes into nodes , the time step is , the spatial step length is In the pipeline and time layer At , the equation is discretized to get:

[0083] (3)

[0084] (4)

[0085] like ,but , , ;

[0086] The simplified dynamic explicit equation of the gas network is:

[0087] (5)

[0088] (6)

[0089] In this embodiment, the subscript Defined as a pipeline The entry parameter, subscript For pipelines Export parameter, superscript Indicates the parameter of the previous moment, with a superscript Represents the parameter at the current moment.

[0090] According to the definition of the two-port model, the known input parameters are the input and output pressure and flow at the previous moment. The parameters at the previous moment can be obtained in real time through the delay module. The output parameters to be calculated are the input and output pressure and flow at the current moment. By solving the above equations simultaneously, the intermediate conversion relationship is extracted, and the modeling is completed in the Simulink environment to obtain the two-port dynamic model of the gas network.

[0091] For the heat network pipelines in this embodiment, the thermal network relies on temperature differences to drive the flow of heat medium, thereby achieving effective heat transfer. Under stable transmission conditions, the heat medium's transmission characteristics within the pipeline can generally be described using the energy conservation equation and the heat transfer equation. If temperature and heat flow are selected as the core parameters describing the system state, the heat medium transmission characteristics in the thermal network can be expressed as:

[0092] (7)

[0093] (8)

[0094] (9)

[0095] Among them, the variables are defined as within the heat network pipeline, is the density of water, For pressure, For traffic, is the mass flow rate base value corresponding to the velocity base value, is the cross-sectional area, is the acceleration due to gravity, is the pipe inclination angle, is the specific heat of water, is the diameter, is the friction coefficient, is the heat dissipation coefficient, is the pipe temperature, is the flow time of water in the heat network pipe, is the distance the water flows in the pipe.

[0096] In this embodiment, it is assumed that the flow direction is In the positive direction, the discrete nodes are numbered , the time step is , the spatial step length is In the pipeline and time layer At , the equation is discretized to get:

[0097] (10)

[0098] (11)

[0099] (12)

[0100] Extract the next moment parameter of the desired output item, , , simplified to:

[0101] (13)

[0102] (14)

[0103] (15)

[0104] In this embodiment, the subscript Understood as a pipeline The entry parameter, subscript For pipelines Export parameter, superscript Indicates the parameter of the previous moment, with a superscript Represents the parameter at the current moment.

[0105] Because simulations make it difficult to treat the heat network as a single model, the network is split into a water supply network and a return network to implement the aforementioned mechanism equations and ensure model feasibility. Similar to the gas network equations, based on the definition of a two-port model, the known input parameters are the input and output temperatures and flow rates at the previous moment, and the desired output parameters are the input and output temperatures and flow rates at the current moment. The intermediate conversion relationship is extracted from the above equations, and modeling is completed in the Simulink environment, resulting in a two-port dynamic model for the heat network.

[0106] In this example, the Simulink dynamic model of coupled devices in an integrated energy system (IES) combines multiple energy sources, such as electricity, gas, and heat, to improve energy efficiency and renewable energy absorption capacity. As the core link in the interaction of multiple energy flows, the dynamic characteristics of coupled devices (such as power-to-gas (P2G), heat pumps (HP), and combined heat and power (CHP)) directly impact the system's operational flexibility, economy, and stability.

[0107] Considering that in related technologies, coupled device models are mostly constructed based on steady-state or quasi-steady-state assumptions, and their dynamic processes are ignored in energy flow calculations and system simulations. Although this simplification reduces the computational complexity, it is difficult to accurately characterize the system state. In response to the above problems, this embodiment proposes a dynamic Simulink model of P2G, HP and CHP on the user side to provide model support for comprehensive energy integrated dynamic simulation software. Power-to-gas equipment can serve as a load on the power grid and can also exist in the natural gas network in the form of a distributed gas source, realizing the coupling of electricity and gas networks and the conversion of electricity and gas energy. At present, power-to-gas technology mainly includes two categories: power-to-hydrogen and power-to-methane. The chemical principle of power-to-hydrogen is the electrolysis reaction of water, while the chemical principle of power-to-methane is to add a methanation reaction on the basis of power-to-hydrogen. In this embodiment, the modeling of P2G will be based on the principle of power-to-methane.

[0108] Using alkaline water electrolysis technology as the modeling basis, the reaction equation is as follows:

[0109] (16)

[0110] The hydrogen produced by the reaction can be further used to undergo methanation to produce methane, or it can be stored and used as a raw material for hydrogen fuel cells; the oxygen produced by the reaction also has multiple uses, such as filling the combustion chamber to ensure full combustion of the gas, or storing it for use in other fields.

[0111] The chemical reaction formula of the methanation process is shown in formula (17), which means that on the basis of producing hydrogen, the obtained and Further reaction under the action of catalyst process. Therefore, the reactants of the reaction Easy to obtain and by-product It has no pollution to the environment, so the reaction is highly environmentally friendly and has low reaction cost.

[0112] (17)

[0113] Since alkaline electrolyzer technology is more mature in industrial applications, the electrolyzer used in the water electrolysis process of this embodiment is modeled using this technology. The electrolyzer can be regarded as a nonlinear load affected by voltage, and the following mathematical model is established. It can be expressed by a semi-empirical formula:

[0114] (18)

[0115] Where: is the number of electrolysis chambers, is the reversible open circuit power threshold, is the Faraday constant, is the number of charge transfers in the reaction. Take 2, , is the ohm voltage related calculation parameter, , is the electrolysis current of the electrolytic cell; is the surface area of ​​the electrolysis chamber; is the electrolyte temperature; 、 、 、 is the calculation parameter related to polarization overvoltage.

[0116] The hydrogen production rate of the electrolyzer is ,unit: .

[0117] By combining the above formulas, the hydrogen production rate of the electrolyzer can be solved and used as the input variable of the methanation stage to complete the model construction of the water electrolysis stage.

[0118] Considering the reactor volume effect and chemical reaction process, a mathematical model of methanation is established. of and 4 of Reaction 1 of and 2 of Gas, the reactor volume is , gas flow into and out of the volume module The flow rates are 、 , the reaction ratio of the inflowing gas is , ignoring the temperature change in the reactor, the expression is as follows:

[0119] (19)

[0120] Where: is the compression factor, is the gas density in the reaction chamber, is the gas pressure in the reaction chamber.

[0121] The gas state equation shows that gas pressure is proportional to density, which controls the flow rate at the reactor outlet. If the pressure remains unchanged, the outlet gas flow rate is proportional to the container pressure:

[0122] (20)

[0123] Where: is the outlet flow rate under rated conditions; is the gas density; is the reactor pressure under rated operating conditions.

[0124] Substituting into equation (19) and performing Laplace transform, the transfer function of the P2G dynamic model is obtained as follows:

[0125] (twenty one)

[0126] Finally, the P2G dynamic model is built and packaged in Simulink.

[0127] The air-source heat pump (HP) technology used in this embodiment is based on the reverse Carnot cycle. It converts natural energy (air heat) into a high-temperature heat source for heating or hot water supply. It boasts high heat collection efficiency, an operating temperature range of -7 to 40°C, year-round, low operating costs, and stable performance. Considering these advantages, this embodiment uses an air-source heat pump model to achieve dynamic heat and cold exchange in an integrated energy system.

[0128] The supply and return water temperatures satisfy the following equation:

[0129] (twenty two)

[0130] (twenty three)

[0131] in, Indicates the pipeline flow rate during the heating process, and Represents the supply water temperature and return water temperature respectively. and They represent the specific heat capacity and density of the hot water in the tank, Indicates the capacity of the hot water tank. Indicates the heat dissipation of the water tank. To lose floor surface temperature, Indicates the heat generated by the heat pump. For a heat pump system, the heat generated by its work is proportional to the power of its compressor. , heat pump performance coefficient Related, it can be expressed as follows:

[0132] (twenty four)

[0133] Here, the internal component Discrete-Time Integrator is used to solve the partial differential equation to improve the solution reliability and calculation efficiency.

[0134] The CHP principle of this embodiment is that the compressor compresses air and forces it into the combustion chamber. The compressed air is mixed with natural gas or other fuel gas in the combustion chamber and combusts. The combustion generates heat, which increases the volume of the gas, drives the blades of the steam turbine to rotate, and then drives the generator to generate electricity. In this process, gas-to-electricity conversion is achieved. Because the exhaust temperature of the gas turbine is very high and can be used as a driving heat source, gas-to-heat conversion is achieved through a heat exchanger. In summary, this embodiment divides the CHP into four parts: compressor, combustion chamber, turbine, and heat exchanger for modeling. The main formulas for each part are as follows:

[0135] (25)

[0136] The variable definition range in the formula is within the compressor module. is the required power; is the inlet pressure; is the outlet pressure; is the efficiency; the polynomial index can be expressed as ; is the export flow; is the module equivalent volume; is the average gas constant of the fuel gas; is the outlet temperature.

[0137] (26)

[0138] The variable definition range in the formula is within the combustion chamber module. is the combustion chamber time constant; is the outlet temperature; For combustion efficiency; is the inlet air enthalpy; is the inlet natural gas enthalpy; is the outlet gas enthalpy; is the inlet natural gas mass flow rate; is the outlet gas mass flow rate; is the constant pressure specific heat capacity of the outlet gas; is the net specific energy of natural gas; is the combustion chamber gas quality; is the air mass flow rate at the combustion chamber inlet.

[0139] This embodiment takes into account the specific heat capacity when building the combustion chamber. Temperature-dependent, more realistic results improve modeling precision and accuracy. Utilizing the working fluid mass ratio (psi) and the reaction relationship (reaction) to calculate mass flow and other parameters, this is used to solve the principle equation. The output is connected to the turbine input.

[0140] (27)

[0141] (28)

[0142] Where: is the turbine outlet temperature; is the turbine inlet temperature; is the turbine pressure ratio; is the turbine efficiency; Power consumed by the turbine; is the turbine equivalent flow rate; , is the gas adiabatic index, is the constant pressure specific heat capacity of the combustion chamber outlet gas.

[0143] The heat exchanger model is not the key innovation of this embodiment and will not be described in detail here. Only the core formula is shown:

[0144] (29) (30)

[0145] Where, is the constant pressure specific heat capacity of water in the shell side, is the density of water in the shell, is the shell-side flow area, is the temperature of the water in the shell, t is the time, is the water velocity in the shell side, is the axial diffusion coefficient of water in the shell, j represents the jth pipe, , is the heat transfer rate from the tube wall per unit length of the j-th shell side to the water in the shell side, , is the shell-side heat transfer coefficient, is the side heat transfer area of ​​water in the shell, L is the tube length, is the wall temperature of pipe j, The positive or negative value of depends on whether the water flow direction in the shell side is along the positive direction of x. When the water flow direction in the shell side is along the positive direction of x, Take the positive, ; When the water in the shell flows in the opposite direction of x, Take the negative, ; is the constant pressure specific heat capacity of water in the tube, is the density of water in the pipe, is the pipe flow area, is the temperature of the water in pipe j, j represents the jth pipe, , t is time, is the flow rate of water in the pipe, x is the flow direction of water at the inlet of the pipe, is the axial diffusion coefficient of water in the tube, is the heat transfer rate from the tube wall per unit length of the j-th tube pass to the water in the tube pass, , is the lateral heat transfer area of ​​water in the tube, is the tube-side heat transfer coefficient, For the head of the pipe, is the wall temperature of pipe j, The positive or negative value of depends on whether the current pipeline is an odd number. When j is an odd number, Take the positive, ; When j is an even number, Take the negative, .

[0146] The core function of the integrated dynamic simulation software for comprehensive energy systems developed in this embodiment is to achieve accurate electrical-gas-heat dynamic simulation, supporting multi-timescale coupled simulation. Users can select a solution method based on their accuracy needs, balancing computational efficiency and accuracy. The software provides a drag-and-drop graphical modeling environment. Users can directly access pre-built dynamic two-port pipeline models for gas and heat networks, as well as Simulink dynamic models for P2G, CHP, heat pumps, and other equipment through a module library, eliminating the need to manually write complex equations and lowering the modeling threshold. After the simulation example is built, the solution algorithm is selected within the software interface. Users can choose based on the characteristics of their system. If the system dynamics are primarily linear (such as small perturbation analysis) or require fast iteration (such as real-time control), the linear finite difference method can be selected. If high-precision nonlinear modeling is required and higher computational costs are acceptable, the nonlinear finite difference method can be selected. Subsequently, a dynamic initialization control command is issued to complete initialization, including reading component parameters and topological connectivity relationships. After initialization is complete, the simulation duration is set and the simulation process is executed to implement dynamic simulation functionality. After the simulation is completed, you can save the results and pop up the simulation results in the form of a report or store them in Excel in the current path.

[0147] In some embodiments, transient processes can be captured through distributed parameter network models and multi-physics field dynamic equations of devices, supporting dynamic interactive simulation of gas-heat-grid. Common major coupling devices such as P2G, HP, CHP, etc. are carefully constructed through Simulink, including operating devices in most application scenarios. This embodiment adopts a modular design, which can flexibly access new device models or external control strategies, and automatically adapt parameters for different application scenarios without rebuilding the network, and is suitable for a variety of application scenarios. In the process of solving the algorithm, this embodiment can choose a variety of options and balance the computational efficiency. Through the processing of the dynamic two-port model and the parallel solver of Simulink, the simulation speed and accuracy are taken into account, and the user can independently choose different solution algorithms according to their own needs. The system provides a user-friendly interface. By developing an integrated software user interface, the operation is simple, the threshold for getting started is low, and a user help manual is configured with a clear functional flow. The system provides a high-reliability platform for dynamic simulation, real-time optimization scheduling and digital twin applications of integrated energy systems. Figure 2 A one-key parameter modification interface is provided to facilitate user operation and use.

[0148] The following is an embodiment of the integrated dynamic simulation system of an integrated energy system provided by the embodiments of the present disclosure. This system and the integrated dynamic simulation method of an integrated energy system in the above-mentioned embodiments belong to the same inventive concept. For details not fully described in the embodiments of the integrated dynamic simulation system of an integrated energy system, please refer to the embodiments of the above-mentioned integrated dynamic simulation method of an integrated energy system.

[0149] The system includes: a parameter feature configuration module for using a dynamic two-port model of an energy network to configure a transfer matrix and a state equation to characterize the dynamic transmission process corresponding to the parameter characteristics of gas network pipelines and the parameter characteristics of heat network pipelines.

[0150] The model building module is used to build a dynamic simulation model of the equipment and couple the P2G electric-gas conversion time delay, the heat pump working fluid phase change thermodynamic transient and the CHP thermoelectric power dynamic decoupling characteristics.

[0151] The simulation processing module is used to combine the nonlinear finite difference method to build an integrated energy system model with a dynamic transmission process and equipment dynamic simulation model, perform dynamic simulation on the built integrated energy system model, and use nonlinear partial differential equations to capture the transient behavior of gas network turbulence and heat pump working fluid phase change to achieve dynamic simulation and save the simulation results.

[0152] like Figure 3 As shown, the present application also provides an electronic device, including a display module 103, a memory 102, a processor 101, and a computer program stored in the memory and executable on the processor 101, wherein the processor 101 implements the steps of the integrated dynamic simulation method of the integrated energy system when executing the program.

[0153] In the embodiments of the present invention, electronic devices include, but are not limited to, laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. Electronic devices may also represent various forms of mobile devices, such as personal digital assistants, cellular phones, smart phones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the embodiments of the present application described and / or claimed herein.

[0154] In the embodiment of the present application, the processor 101 can be implemented by using at least one of an application-specific integrated circuit (ASIC), a programmable logic device (PLD), a field programmable gate array (FPGA), a processor, a controller, a microcontroller, a microprocessor, and an electronic unit designed to perform the functions described herein. In some cases, such an embodiment can be implemented in a controller. For software implementation, an embodiment such as a process or function can be implemented with a separate software module that allows the execution of at least one function or operation. The software code can be implemented by a software application (or program) written in any appropriate programming language, and the software code can be stored in a memory and executed by a controller.

[0155] The display module 103 is used to display information input by the user or information provided to the user. The display module 103 may include a display panel, which may be configured in the form of a liquid crystal display (LCD), an organic light-emitting diode (OLED), etc.

[0156] The memory 102 can be used to store software programs and various data. The memory 102 can include high-speed random access memory and non-volatile memory, such as at least one disk storage device, flash memory device, or other volatile solid-state storage device.

[0157] The present application also provides a storage medium having a computer program stored thereon, which implements the steps of the integrated dynamic simulation system of the comprehensive energy system when the computer program is executed by a processor.

[0158] The storage medium can be any combination of one or more readable media. The readable medium can be a readable signal medium or a readable storage medium. The readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or component, or any combination thereof. More specific examples (non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof.

[0159] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An integrated dynamic simulation method for a comprehensive energy system, characterized in that: Methods include: Based on the dynamic two-port model of the energy network, the transfer matrix and state equation are configured to characterize the dynamic transmission process corresponding to the parameter characteristics of the gas network pipeline and the heat network pipeline. Build a dynamic simulation model of the equipment and couple the P2G electricity-gas conversion time delay, the heat pump working fluid phase change thermodynamic transient, and the CHP thermoelectric power dynamic decoupling characteristics; In the coupled P2G electric-gas conversion time lag, the P2G dynamic model transfer function is defined as: in, 、 are the flow rates of gas flowing into and out of the volume module, is the reaction ratio of the inflowing gas, is the reactor volume, is the outlet flow rate under rated conditions, is the reactor pressure under rated conditions, s is the Laplace transform variable, p is the pressure, is the representation of the output in the Laplace domain, is the representation of the input in the Laplace domain; In the heat pump working medium phase change thermodynamic transient state of the equipment dynamic simulation model, the supply and return water temperatures are defined to satisfy the following equations: in, Indicates the pipeline flow rate during the heating process, and Represents the supply water temperature and return water temperature respectively. and They represent the specific heat capacity and density of the hot water in the tank, Indicates the capacity of the hot water tank. Indicates the heat dissipation of the water tank. To lose floor surface temperature, Indicates the heat generated by the heat pump. For a heat pump system, the heat generated by its work is proportional to the power of its compressor. , heat pump performance coefficient Related, expressed as follows: ； In the step of constructing the dynamic decoupling characteristics of the CHP thermoelectric power of the equipment dynamic simulation model, the CHP is divided into four parts: compressor, combustion chamber, turbine, and heat exchanger for modeling. The main formulas of each part are as follows: The variable definition range in the formula is within the compressor module. is the required power; is the inlet pressure; is the outlet pressure; is the efficiency; the polynomial index can be expressed as ; is the export flow; is the module equivalent volume; is the average gas constant of the fuel gas; is the outlet temperature; The variable definition range in the formula is within the combustion chamber module. is the combustion chamber time constant; is the outlet temperature; For combustion efficiency; is the inlet air enthalpy; is the inlet natural gas enthalpy; is the outlet gas enthalpy; is the inlet natural gas mass flow rate; is the outlet gas mass flow rate; is the constant pressure specific heat capacity of the outlet gas; is the net specific energy of natural gas; is the combustion chamber gas quality; is the air mass flow rate at the combustion chamber inlet; The output is connected to the turbine input as follows: Where: is the turbine outlet temperature; is the turbine inlet temperature; is the turbine pressure ratio; is the turbine efficiency; Power consumed by the turbine; is the turbine equivalent flow rate; , is the gas adiabatic index, is the constant pressure specific heat capacity of the combustion chamber outlet gas; Based on the nonlinear finite difference method, a comprehensive energy system model with a dynamic transmission process and equipment dynamic simulation model is built. The built comprehensive energy system model is dynamically simulated, and the transient behavior of gas network turbulence and heat pump working fluid phase change is captured with nonlinear partial differential equations to achieve dynamic simulation and save the simulation results.

2. The integrated dynamic simulation method of the comprehensive energy system according to claim 1, characterized in that: The dynamic transmission process of the gas network pipeline is: in, is the density of natural gas, is the natural gas transmission speed, For pressure, is the diameter, is the friction coefficient, is the acceleration due to gravity, is the pipe inclination angle; the subscript in the parameter For pipelines The entry parameter, subscript For pipelines Export parameter, superscript Indicates the parameter of the previous moment, with a superscript Represents the parameter at the current moment.

3. The integrated dynamic simulation method of the comprehensive energy system according to claim 2, characterized in that: In this method, based on the dynamic two-port model of the energy network, the known input parameters are the input and output pressure and flow at the previous moment, and the desired output parameters are the input and output pressure and flow at the current moment. The intermediate conversion relationship is extracted from the parameter characteristics of the gas network pipeline, and the modeling is completed in the Simulink environment to obtain the two-port dynamic model of the gas network.

4. The integrated dynamic simulation method of a comprehensive energy system according to claim 1 or 2, characterized in that: The heat medium transmission characteristics in the heat network pipeline are expressed as: Among them, the variables are defined as within the heat network pipeline, is the density of water, For pressure, For traffic, is the mass flow rate base value corresponding to the velocity base value, is the cross-sectional area, is the acceleration due to gravity, is the pipe inclination angle, is the specific heat of water, is the diameter, is the friction coefficient, is the heat dissipation coefficient, is the pipe temperature, is the flow time of water in the heat network pipe, is the flow distance of water in the pipe; Define the flow direction as In the positive direction, the discrete nodes are numbered , the time step is , the spatial step length is , in the pipeline and time layer At , the equation is discretized to get: Among them, the subscript For pipelines The entry parameter, subscript For pipelines Export parameter, superscript Indicates the parameter of the previous moment, with a superscript Represents the parameter at the current moment.

5. An integrated dynamic simulation system for a comprehensive energy system, characterized in that: The system is used to implement the integrated dynamic simulation method of the comprehensive energy system according to any one of claims 1 to 4; The system includes: The parameter feature configuration module is used to use the energy network dynamic two-port model to configure the transfer matrix and state equation to characterize the dynamic transmission process corresponding to the parameter characteristics of the gas network pipeline and the heat network pipeline; The model building module is used to build a dynamic simulation model of the equipment and couple the P2G electric-gas conversion time delay, the heat pump working fluid phase change thermodynamic transient and the CHP thermoelectric power dynamic decoupling characteristics; The simulation processing module is used to combine the nonlinear finite difference method to build an integrated energy system model with a dynamic transmission process and equipment dynamic simulation model, perform dynamic simulation on the built integrated energy system model, and use nonlinear partial differential equations to capture the transient behavior of gas network turbulence and heat pump working fluid phase change to achieve dynamic simulation and save the simulation results.

6. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the steps of the integrated dynamic simulation method for a comprehensive energy system as described in any one of claims 1 to 4 are implemented.

7. A storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the integrated dynamic simulation method for a comprehensive energy system as claimed in any one of claims 1 to 4 are implemented.

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