Distributed comprehensive energy optimization operation system, optimization method and medium

Abstract

The invention relates to the technical field of renewable energy sources, and discloses a distributed comprehensive energy optimization operation system, an optimization method and a medium, and the system comprises a heat supply network model and an equipment operation model, the energy storage capacity of the heat supply pipe network is fully utilized to carry out economic optimization scheduling. Meanwhile, an optimization solution method based on the model is provided, and the solution complexity is reduced by constructing a hydrogen-electricity coupling sub-model and a heat supply sub-model and hierarchically processing operation strategies of hydrogen energy equipment and heat supply equipment. According to the solving method, coupling of hydrogen energy equipment and power equipment is preferentially considered, efficient consumption of renewable energy sources such as photovoltaic energy is achieved, and the temperature and flow of a pipeline heat medium are dynamically adjusted in the system. The adaptability and flexibility of the integrated energy system can be effectively improved, and system operation is optimized.

Description

Technical Field

[0001] The present invention belongs to the technical field of renewable energy, and relates to an optimized operation system, an optimization method and a medium of distributed comprehensive energy. Background Art

[0002] With the intensification of the global energy crisis and environmental pollution problems, distributed integrated energy systems have attracted attention due to their high energy utilization efficiency and environmental friendliness. In a distributed integrated energy system composed of multiple integrated energy stations, each energy station is connected to each other through the power grid and the heat network to achieve mutual coordination. Unlike the power grid, the regional heating network, as a medium for heat energy transmission, has high transmission loss and transmission delay. On the one hand, this feature makes it difficult to model the heat network of the distributed integrated energy system, but on the other hand, it also shows that the heating pipeline network has a certain energy storage capacity. Therefore, a set of distributed integrated energy system heating network models is needed to accurately describe the heating network dynamically, so as to give full play to the regulatory potential of the heat network energy storage in the optimization of the economic operation of the distributed integrated energy system.

[0003] In addition, hydrogen energy, as a clean energy, is widely used in distributed integrated energy systems. Hydrogen energy and electric energy are both secondary energy sources. In hydrogen-containing integrated energy systems, new energy sources such as wind power and photovoltaic power can be converted into hydrogen energy and stored through electrolysis when they are in surplus. During peak energy consumption, hydrogen energy can be converted into electricity and heat energy through hydrogen fuel cells. Hydrogen energy is not only related to electricity and heat energy, but also coupled with renewable energy, natural gas, and power grids. Considering the volatility, complementarity, and real-time needs of different energy sources, how to efficiently coordinate the flow of hydrogen energy with electricity and heat energy in a system is a huge challenge. Summary of the invention

[0004] In view of the problems existing in the prior art, the present invention provides an optimized operation system, optimization method and medium of a distributed integrated energy, which can more accurately describe the dynamic change characteristics of the heating pipeline, give play to the regulatory potential of the heating network energy storage in the operation optimization of the distributed integrated energy system, and realize the efficient coordination of the flow of hydrogen energy, electricity and thermal energy in a system.

[0005] The present invention is achieved through the following technical solutions: A method for establishing an optimized operation system of distributed integrated energy, comprising: Based on the internal operation structure of the distributed integrated energy system and the operation mechanism of each internal device, an internal device operation model is established to obtain the internal device operation constraints; Based on the heat loss of the heat medium in the heating pipeline, a heating network model of the pipeline heat transfer characteristics is established to obtain the heating network operation constraints; Based on the relationship between the supply and consumption of energy in the distributed integrated energy system, energy and heat balance constraints are obtained; An energy optimization model is established based on internal equipment operation constraints, heat network operation constraints, and energy and heat balance constraints; the energy optimization model includes a hydrogen-electricity coupling sub-model and a heat supply sub-model; Based on the internal equipment operation model, the heat network model and the energy optimization model, the distributed integrated energy system operation model is obtained jointly.

[0006] Preferably, the internal equipment operating constraints include: operating constraints of photovoltaic panels, operating constraints of electric chillers, operating constraints of electric boilers, operating constraints of heat pumps, operating constraints of electrolyzers, operating constraints of fuel cells, operating constraints of power storage units, operating constraints of hydrogen storage tanks, and operating constraints of energy storage water tanks.

[0007] Preferably, the heat network operation constraints include node flow balance constraints, node energy conservation constraints, pipeline water supply and return water temperature constraints, and pipeline heat transfer characteristic constraints.

[0008] Preferably, the hydrogen-electricity coupling sub-model is established through heat network model constraints, internal equipment operation constraints, energy balance constraints, and heat constraints at the heat source end and the load end; the energy balance constraints include electricity balance constraints and heat and cold balance constraints.

[0009] Preferably, the objective function of the hydrogen-electricity coupling sub-model is a function for minimizing the cost of purchasing electricity and hydrogen, and the specific formula is:

[0010] in, is the number of energy stations, and They are the first The cost of purchasing electricity and hydrogen for each energy station.

[0011] Preferably, the heating sub-model is established by means of heating network operation constraints, heating and cooling related equipment operation constraints in internal equipment operation constraints, cooling and heating balance constraints, and heat constraints at the heat source end and the load end; The operation constraints of the heating and cooling related equipment include electric boiler operation constraints, electric refrigerator operation constraints, heat pump operation constraints, water tank operation constraints and fuel cell operation constraints.

[0012] Preferably, the objective function of the heating sub-model is a function for minimizing the electricity purchase cost, and the specific formula is:

[0013] in, is the number of energy stations, The first The electricity purchase cost of an energy station.

[0014] Preferably, the internal operating structure is an energy transmission system in which the energy station, the energy storage water tank and the user area are connected through a heating pipeline network.

[0015] A distributed integrated energy optimization operation system is obtained based on the method for establishing the distributed integrated energy system operation model.

[0016] An optimization solution method for an optimized operation system of distributed integrated energy, comprising: Solve the hydrogen-electricity coupling sub-model to obtain the operation strategy and cost of the distributed integrated energy system, and transfer the operation strategy of the hydrogen energy equipment and the temperature of the heating pipeline to the heating sub-model as the initial conditions; Solve the heating sub-model, update the pipeline flow rate with the heat flow rate result obtained, and then feed the updated pipeline flow rate back to the hydrogen-electricity coupling sub-model, iteratively solve the hydrogen-electricity coupling sub-model until the optimal operation strategy and operation cost are obtained, specifically: Determine whether the ratio of the difference between the current operating cost of the distributed integrated energy system and the operating cost obtained in the previous iteration and the current operating cost is less than a preset threshold; If it is less than the preset threshold, the iteration is stopped, and the current operation strategy of the distributed integrated energy system is used as the economically optimal operation strategy, and the operation of the distributed integrated energy system is controlled by using this strategy; If it is not less than the preset threshold, the operation strategy of the hydrogen energy equipment in the current strategy is passed to the heating sub-model as the initial condition, and the iteration is continued until the economically optimal operation strategy is obtained.

[0017] An optimization solution system for an optimized operation system of distributed comprehensive energy is obtained based on the optimization solution method for an optimized operation system of distributed comprehensive energy.

[0018] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of an optimization solution method for an optimized operation system of a distributed integrated energy source.

[0019] Compared with the prior art, the present invention has the following beneficial technical effects: The present invention constructs a set of distributed integrated energy system operation models, in which the heat network model takes into account the transient characteristics of the heat medium temperature, accurately describes the temperature change of the heat medium in the heating pipeline, and proposes a method for judging the transient heat transfer characteristics and steady-state heat transfer characteristics of the pipeline according to the scheduling cycle and the length, inner diameter, and flow rate of the pipeline, thereby establishing a dynamic model of the heating pipeline network of the distributed integrated energy system, reducing the influence of the heat loss and heat transfer delay of the heating pipeline on the operation and scheduling of the distributed integrated energy system. It can also give play to the regulation ability of the potential energy storage of the heating pipeline network in the operation optimization of the distributed integrated energy system, and realize the efficient coordination of the flow of hydrogen energy, electricity, and heat energy in one system.

[0020] Furthermore, the present invention proposes a method for optimizing the operation of a distributed integrated energy system for the model. The method gives priority to hydrogen-electricity coupling, and solves the operation strategy of hydrogen-related equipment in the hydrogen-electricity coupling sub-model. While reducing the complexity of the model solution, it gives full play to the ability of hydrogen energy to absorb renewable energy such as photovoltaics, and enhances the adaptability and flexibility of the integrated energy system. In addition, in the operation solution of the heating network, compared with the traditional constant temperature variable flow and constant flow variable temperature schemes, the pipeline heat medium flow and temperature are considered and adjusted at the same time, and the heating network is described more accurately. The method of solving the pipeline heat medium temperature and flow in the hydrogen-electricity coupling sub-model and the heating sub-model respectively, while ensuring a certain degree of feasibility and optimality, also avoids the solution difficulties caused by nonlinear constraints of temperature and flow. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the implementation mode will be briefly introduced below. Obviously, the drawings described below are only some implementation modes of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 It is a structural diagram of a distributed integrated energy system provided by an embodiment of the present invention.

[0023] Figure 2 It is a schematic diagram of the internal structure of an energy station in the distributed integrated energy system provided by an embodiment of the present invention.

[0024] Figure 3 It is a basic structural schematic diagram of a heating pipeline model provided in an embodiment of the present invention.

[0025] Figure 4 It is a flow chart of a distributed integrated energy system operation optimization solution method provided by an embodiment of the present invention; Figure 5It is a flow chart of the distributed integrated energy system model establishment and operation optimization solution method described in the present invention. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below in conjunction with specific embodiments, which are intended to explain the present invention rather than to limit it.

[0027] In a first aspect, the present invention provides a distributed integrated energy system model, which includes a heat network model and an equipment operation model; wherein: The constraints of the heat network model include node flow balance, node energy conservation, pipeline supply and return water temperature constraints, and pipeline heat transfer characteristics; The node flow balance constraint is used to describe that the water flow rate flowing into a node at each moment in the heat network pipeline node is equal to the water flow rate flowing out of the node; The node energy conservation constraint is used to describe that the heat entering a node at each moment in the heat network pipeline node is equal to the heat flowing out of the node; The pipeline heat transfer characteristic constraint takes into account the transient temperature change of the heat medium in the heat network, and uses the pipeline length, pipeline inner diameter, flow rate, etc. to calculate the pipeline transmission delay, and compares the pipeline transmission delay with the time scale of system operation scheduling to determine the steady-state and transient heat transfer characteristics of the pipeline.

[0028] Optionally, the constraints in the equipment operation model include operation constraints of power generation equipment such as photovoltaic panels, operation constraints of heat and cold generation equipment such as air source heat pumps, sewage source heat pumps, ground source heat pumps, electric chillers, electric boilers, operation constraints of hydrogen energy equipment such as electrolyzers and fuel cells, and operation constraints of energy storage equipment such as hydrogen storage tanks, power storage units, and energy storage water pipes. Among them, the energy storage water tank is placed independently outside the heat source end in the system as a heat (cold) storage device, and its input and output heat is not included in the heat (cold) generation of the heat source end.

[0029] The energy balance constraints include electrical balance constraints, thermal balance constraints, and cold balance constraints.

[0030] The heat constraints at the heat source end and the load end describe the relationship between the heat entering and leaving each heat source end and the load end and the water flow and temperature flowing into and out of the heat source or load.

[0031] Secondly, based on the distributed integrated energy system operation model, an energy optimization model of the distributed integrated energy system is established, and the energy optimization model includes a hydrogen-electricity coupling sub-model and a heating sub-model.

[0032] The hydrogen-electricity coupling sub-model ensures that the system operation cost is minimized while meeting the user load demand through the constraints of the heat network model, equipment operation constraints, energy balance constraints, and heat constraints at the heat source and load ends. Its objective function is to minimize the cost of purchasing electricity and hydrogen.

[0033] The energy balance constraint ensures the conservation relationship between the energy supplied by the system and the user's demand, including the electricity balance constraint and the heat and cold balance constraint; wherein, The electric balance constraint comprehensively considers photovoltaic power generation, fuel cell power generation, discharge and charging of power storage units, power consumption of electrolyzers, and power consumption of electric boilers, heat pumps, electric refrigerators and other equipment to meet the user's electric load demand; The heat and cold balance constraint is based on the heat and cold production of equipment such as fuel cells, heat pumps, electric boilers, and the heat and cold release of energy storage tanks to ensure that the user's heat and cold load requirements are met.

[0034] The heat source end heat constraint further describes the relationship between the total output heat of the energy station and the heat generated by the equipment, as well as the relationship between the output heat and the inlet and outlet water temperature and flow rate, to ensure that the system operation matches the user load demand.

[0035] The heating sub-model includes constraints on the heating network model, constraints on the operation of heating and cooling related equipment, constraints on the balance of heat and cold, and constraints on the heat source and load ends, and its objective function is to minimize the cost of purchasing electricity. The constraints in the model include operating constraints on equipment such as electric boilers, electric chillers, heat pumps, water tanks, fuel cells, and the energy balance relationship in the system's heating and cooling process to meet the needs of users' electric load, heating load, and cooling load.

[0036] In a third aspect, the present invention provides a method for solving system operation optimization for the proposed distributed integrated energy system energy optimization model, so as to determine the economically optimal operation strategy of the system. The method comprises: Based on the solution method, the hydrogen-electricity coupling sub-model and the heating sub-model are iteratively solved; in each round of iterative solution process: According to the existing pipeline flow, the hydrogen-electricity coupling sub-model is solved, the operation strategy and operation cost in the solution are saved, and the operation strategy of the hydrogen energy equipment and the temperature of each heating pipeline are passed to the heating sub-model as the initial conditions. Then the heating sub-model is solved, the pipeline flow is solved and updated, and the updated pipeline flow is passed to the hydrogen-electricity coupling sub-model, and the hydrogen-electricity coupling sub-model is solved again to obtain the new operation strategy and operation cost.

[0037] Determine whether the ratio of the difference between the current operating cost and the operating cost obtained in the previous iteration and the current operating cost is less than a preset threshold; If so, stop the iteration, take the current operation strategy as the economically optimal operation strategy, and use this strategy to control the operation of the distributed integrated energy system.

[0038] If not, the operation strategy of the hydrogen energy equipment in the current strategy is passed to the heating sub-model as the initial condition, and the iteration is continued until the optimal operation strategy is obtained.

[0039] The distributed integrated energy system model of the present invention and its optimization solution method. It includes a heat network model, an equipment operation model, and an energy optimization model; wherein the heat network model accurately describes the flow balance, energy conservation, and especially the heat transfer characteristics of the heat network pipeline, so as to make full use of the energy storage capacity of the heating network for economic optimization scheduling. At the same time, an optimization solution method based on this model is proposed. By constructing a hydrogen-electric coupling sub-model and a heating sub-model in the energy optimization model, the operation strategies of hydrogen energy equipment and heating equipment are processed in layers, thereby reducing the complexity of the solution. The solution method gives priority to the coupling of hydrogen energy equipment and power equipment, realizes the efficient consumption of renewable energy such as photovoltaics, and dynamically adjusts the temperature and flow of pipeline heat medium in the system. It can effectively improve the adaptability and flexibility of the integrated energy system and optimize the operation of the system.

[0040] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings 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 should fall within the scope of protection of the present invention.

[0041] Example 1 The present invention is based on the internal equipment operation model, the heat network model and the energy optimization model, and obtains the distributed integrated energy system operation model. The operation optimization solution method thereof is as follows: Figure 5 As shown, the following steps are included: S1. Establishing an internal operation structure of a distributed integrated energy system under a typical scenario, establishing an internal equipment operation model based on the internal equipment and operation mechanism of the internal operation structure, and obtaining internal equipment operation constraints; wherein S1 includes the following steps: S101. Establish the internal operation structure of the distributed integrated energy system under typical scenarios: Please refer to Figure 1In a first aspect, an embodiment of the present invention provides a distributed integrated energy system model, specifically comprising: 5 energy stations (SOURCE1, SOURCE2, SOURCE3, SOURCE4, SOURCE5), each energy station is provided with a storage water tank (WT1, WT2, WT3, WT4, WT5), and 5 user areas (LOAD1, LOAD2, LOAD3, LOAD4, LOAD5).

[0042] Specifically, the energy station, energy storage water tank and user area are connected by a heating pipe network, which consists of pipes 1 to 40 in the figure, where the red pipe is the water supply pipe, the blue pipe is the return pipe, and the arrows on the pipes indicate the flow direction of the heat medium in the pipes.

[0043] If the energy station, energy storage tank, and user area have the same serial number, it means that they are in the same area. For example, the energy station SOURCE1, energy storage tank WT1, and user area LOAD1 are distributed in area 1. The energy station, energy storage tank, and user area supply pipe and return pipe in the same area are respectively connected to the public nodes in the area. For example, the supply pipe of the energy station SOURCE1, energy storage tank WT1, and user area LOAD1 is connected to node 1, and the return pipe is connected to node 10.

[0044] It should be noted that in order to emphasize the heating pipeline network of the distributed integrated energy system, the power supply network between the energy station and the user load is omitted in the figure.

[0045] Please refer to Figure 2 The energy station provided in this embodiment is specifically a hydrogen-containing comprehensive energy station, and the equipment included in the energy station specifically includes power supply equipment, heating equipment, cooling equipment, hydrogen energy equipment and energy storage equipment.

[0046] Specifically, the power supply equipment includes photovoltaic panels; the heating equipment includes electric boilers, air source heat pumps, ground source heat pumps, and sewage source heat pumps; the cooling equipment includes electric refrigerators, air source heat pumps, ground source heat pumps, and sewage source heat pumps; the hydrogen energy equipment includes electrolyzers and hydrogen fuel cells, among which the hydrogen fuel cell is also a cogeneration device; the energy storage equipment includes a power storage unit and a hydrogen storage tank.

[0047] Specifically, photovoltaic panels are used to supply electricity to energy stations, or to supply electricity to electric chillers, electric boilers, heat pumps, electrolyzers and other equipment. Energy stations can also purchase electricity from the power grid. Excess electricity can be stored in power storage units.

[0048] After the electrolyzer completes hydrogen production, the hydrogen is transported to the hydrogen storage tank, which is used to provide hydrogen for the hydrogen fuel cell.

[0049] Specifically, the hydrogen stored in the hydrogen storage tank can also be purchased from outside.

[0050] Air source heat pumps, ground source heat pumps, and sewage source heat pumps operate in heat generation mode during the heating season, and their heat generation, together with the heat generation of electric boilers and hydrogen fuel cells, constitute the heating supply of the energy station; in the cooling season, air source heat pumps, ground source heat pumps, and sewage source heat pumps operate in cooling mode, and their cooling capacity, together with the cooling capacity of the electric chiller, constitute the cooling capacity of the energy station.

[0051] S102: Based on the internal operation structure, a model is established for each internal device according to the operation mechanism of each internal device to obtain an operation model and operation constraints of the internal device: Specifically, the operating constraints of the photovoltaic panels are:

[0052] in, is the power generation of the photovoltaic panel at time t, is the photovoltaic system efficiency. is the total area occupied by the panels. is the radiation value at time t.

[0053] The operating constraints of the electric chiller are:

[0054] in, The power consumption of the electric chiller at time t, is the refrigeration efficiency coefficient of the electric refrigerator, is the cooling capacity of the electric chiller at time t, is the maximum power of the electric chiller.

[0055] The operating constraints of the electric boiler are:

[0056] in, is the power consumption of the electric boiler at time t, is the power generation efficiency coefficient of the electric boiler, is the heat output of the electric boiler at time t, It is the maximum power generation capacity of the electric boiler.

[0057] The operating constraints of the heat pump are:

[0058] in, is the heat pump operation mode at time t ( When it is heating, refrigeration when is the power consumption of the heat pump at time t, and are the heating and cooling capacities of the heat pump at time t, and are the heating and cooling efficiency coefficients of the heat pump, is the maximum power of the heat pump.

[0059] The operating constraints of the electrolyzer are:

[0060] in, is the hydrogen production of the electrolyzer at time t, is the hydrogen production efficiency coefficient of the electrolyzer, is the power consumption of the electrolytic cell at time t, is the maximum power of the electrolyzer.

[0061] The operating constraints of the fuel cell are:

[0062] in, is the hydrogen consumption of the fuel cell at time t, is the power generation of the fuel cell at time t, is the calorific value of hydrogen, is the power generation efficiency coefficient of the fuel cell, is the heat generated by the fuel cell at time t, is the heat generation efficiency coefficient of the fuel cell, is the maximum power of the fuel cell.

[0063] The operating constraints of the power storage unit are:

[0064] in, is the discharge amount of the storage unit at time t, is the state of the power storage unit at time t, When it indicates discharge, It indicates charging.

[0065] The operating constraints of the hydrogen storage tank are:

[0066] in, is the state of the hydrogen storage tank at time t, is the amount of hydrogen purchased at time t, is the maximum storage and release rate of hydrogen in the hydrogen storage tank, is a scheduling cycle.

[0067] In addition, the operating constraints of the energy storage tank are:

[0068] in, Heat the water tank. When indicates heat release / cold storage, When it is on, it means cooling / heat storage. is the energy storage state of the water tank, is the water storage capacity of the water tank, is the water temperature in the water tank, and are the inlet and outlet water temperatures of the water tank, is the water flow rate in and out of the water tank, and are the specific heat capacity and density of water respectively.

[0069] S103, establishing a heat network model of pipeline heat transfer characteristics based on the heat loss of the heat medium in the heating pipeline, thereby obtaining the operation constraints of the heating network; Please refer to Figure 3 The pipeline heat transfer characteristic model provided in this embodiment takes into account the heat loss of the heat medium in the heating pipeline. First, the pipeline with a length of The initial temperature of the heat medium when it is emitted from the heat source is .

[0070] Initially, the heat medium micro-element energy for

[0071] in, is the inner diameter of the pipe, is the return water temperature of the pipe.

[0072] The interaction between the heat medium micro-elements is not considered, and only the heat dissipated outward by the heat medium micro-elements through the pipe wall is considered. , according to Fourier's law:

[0073] in, is the thermal conductivity of the pipe. It is the heat transfer area of ​​the isothermal surface of the heat medium microelement. is the pipe wall thickness. is the external environment temperature.

[0074] The heat lost from the heat source after t time is:

[0075] The energy of the heat medium microelement at time t can be obtained by subtracting the lost heat from the initial energy:

[0076] According to the above formula, the temperature of the heat medium microelement at time t is obtained:

[0077] The relationship between heat medium transmission time and transmission distance Substituting the above formula and taking the linear part of its Taylor expansion, we can get the steady-state temperature of the point in the pipeline at a distance x from the heat source:

[0078] in .

[0079] The pipeline heat transfer characteristic model assumes that the temperature of a point x in the pipeline changes linearly. The transient heat transfer characteristics of the pipeline can be expressed as follows:

[0080] in, and are the heat source temperatures in the initial state and the steady state, respectively. .when When , the heat medium microelement starting from the heat source has not reached the distance x from the heat source, and the temperature there has not reached a steady state; when When , the heat medium microelement starting from the heat source has reached the distance x from the heat source, where the temperature reaches a steady state.

[0081] Specifically, in The heat medium microelement starts from the head of a pipe with a length of L at the moment. After that, if the end of the pipeline is not reached, , the pipeline can never reach a steady state. At the time (i.e. when the next scheduling starts), the temperature at the end of the pipeline can be expressed as:

[0082] In the scheduling cycle Afterwards, if the heat medium microelement flowing from the pipe head has reached the end of the pipe, that is, , then the pipeline can reach a steady state. At the time (i.e. when the next scheduling starts), the temperature at the end of the pipeline can be expressed as:

[0083] in, for The temperature at the end of the pipeline at the time (i.e. the last scheduling), for Pipe head temperature at all times.

[0084] In addition, for each pipeline node in the heating network, the medium flow rate flowing into it at each moment should be equal to the medium flow rate flowing out of it, so there is a node flow balance constraint:

[0085]

[0086] in and They are the upper and lower connection matrices of the heat network respectively. is the flow column vector. is the pipeline flow rate of the i-th branch.

[0087] For each pipeline node, the node energy conservation constraint should also be satisfied:

[0088]

[0089] in and are the head temperature and the end temperature of pipe i, respectively, where i=1, 2, ..., 40.

[0090] The temperature of node n is equal to the energy of the outflowing medium:

[0091] in is the temperature of the ith node. is the initial temperature of the pipe directly connected to the i-th node and the hot medium flows out of the node.

[0092] For energy stations and user areas, there are also constraints on the supply and return water temperatures:

[0093] In the formula, They are the supply and return water temperatures of the energy station respectively. and They are the supply and return water temperatures in the user area respectively.

[0094] S2. Based on the relationship between the supply and consumption of energy in the distributed integrated energy system, obtain energy and heat balance constraints, establish an energy optimization model based on internal equipment operation constraints, heat network operation constraints, and energy and heat balance constraints, and establish an energy optimization model for the distributed integrated energy system, wherein the energy optimization model includes a hydrogen-electricity coupling sub-model and a heating sub-model. S2 includes the following steps: S201. The heat network model constraints, equipment operation constraints, energy balance constraints, heat source end and load end heat constraints are summarized into a hydrogen-electricity coupling sub-model: The output result of the hydrogen-electricity coupling sub-model is used to ensure that the system operation cost is minimized while meeting the user load demand. Therefore, the objective function of the hydrogen-electricity coupling sub-model is:

[0095] in, is the number of energy stations in the embodiment, and They are the first The cost of purchasing electricity and hydrogen for each energy station.

[0096] The constraints of the hydrogen-electricity coupling sub-model are set as the thermal network model constraints, equipment operation constraints, energy balance constraints, and heat constraints at the heat source end and the load end.

[0097] The energy balance constraint refers to the conservation of energy supplied and consumed by the distributed integrated energy system, including electricity balance constraint and heat and cold balance constraint.

[0098] The electrical balance constraint can be expressed as ,in, , They are the power generation of photovoltaic panels and fuel cells at each moment. is the storage and discharge capacity of the power storage unit at each moment, is the amount of electricity purchased from the grid at each moment, is the power consumption of the electrolytic cell at each moment, The power consumption of the electric boiler at each moment, The power consumption of each type of heat pump at each moment, is the power consumption of the electric chiller at each moment, is the electrical load at each moment.

[0099] The heat and cold balance constraint can be expressed as ,in, The fuel cell generates heat every moment. The heat generated by each type of heat pump at each moment, The cooling capacity of each type of heat pump at each moment, The cooling capacity of the electric chiller at each moment, The electric boiler generates heat every moment. Heat is released to the water tank every moment. When it is heat released, When it is cooled, is the cooling and heating load at each moment, When represents the heat load, : indicates cooling load.

[0100] The heat constraint at the heat source end refers to the relationship between the total heat output of each energy station and the heat output of each device, as well as the relationship between the total heat output and the inlet and outlet water temperature and flow rate, which can be specifically expressed as:

[0101]

[0102] in, is the total heat output of energy station i, is the inlet and outlet water flow of energy station i, is the outlet water temperature of energy station i, is the inlet water temperature of energy station i.

[0103] The load-side heat constraint refers to the relationship between the total input heat of each load and the inlet and outlet water temperature and flow rate, which can be specifically expressed as:

[0104] in, is the total input heat of load i, is the inlet and outlet water flow of load i, is the outlet water temperature of load i, is the inlet water temperature of load i.

[0105] It should be noted that the distributed integrated energy system is mainly used to supply energy to users. Therefore, the output of each energy source mainly depends on the user's load demand.

[0106] The load demand specifically includes user electrical load, heating load and cooling load.

[0107] S202, summarizing the heat network model constraints, heating and cooling related equipment operation constraints, cooling and heating balance constraints, heat source and load end heat constraints into a heating sub-model: In this embodiment, since the part related to hydrogen energy has been solved in the hydrogen-electricity coupling sub-model, the objective function of the heating sub-model is:

[0108] in, is the number of energy stations in the embodiment, The first The electricity purchase cost of an energy station.

[0109] The heat network model constraints specifically include the heat network operation constraints in the distributed integrated energy system operation model.

[0110] The operation constraints of the heating and cooling related equipment specifically include the electric boiler operation constraints, electric refrigerator operation constraints, heat pump operation constraints, water tank operation constraints, and fuel cell operation constraints in the distributed integrated energy system operation model.

[0111] The heat and cold balance constraint can be expressed as .

[0112] The heat source end heat constraint is expressed as:

[0113]

[0114] The load end heat constraint is expressed as:

[0115] The meanings of the symbols are the same as those of the cold-heat balance constraints and the heat constraints at the heat source end in the hydrogen-electric coupling sub-model.

[0116] S3. According to the energy optimization model, iteratively solve the hydrogen-electricity coupling sub-model and the heating sub-model to optimize the operation of the distributed integrated energy system. Figure 4 , S3 includes the following steps: S301, set initial value: Set the initial pipeline flow and the number of iterations , system initial operating cost .

[0117] It should be noted that the setting of the initial pipeline flow only provides a starting point for the solution process and will not affect the final solution result. However, when setting the initial pipeline flow, the node flow balance constraint must be met.

[0118] Setting the initial operating cost of the system to positive infinity can ensure that the operating cost obtained from the initial solution must be smaller than the current operating cost, thus ensuring the feasibility of the solution algorithm.

[0119] S302, using initialization parameters to perform the initial solution to the hydrogen-electric coupling sub-model: The given initial pipeline flow is substituted into the hydrogen-electricity coupling sub-model for solution, the operation strategy and operation cost in the solution are saved, and the operation strategy of the hydrogen energy equipment and the temperature of the heat medium in each heating pipeline are passed to the heating sub-model as initial conditions.

[0120] In this embodiment, when solving the hydrogen-electricity coupling sub-model, since the heating pipeline flow rate has been given, there is no need to consider the node flow balance constraint.

[0121] S303, solving the heating sub-model, and using the solution of the heating sub-model to iteratively solve the hydrogen-electric coupling sub-model: The heating sub-model is solved using the operating strategy of the hydrogen energy equipment and the temperature of each heating pipeline from the solution results of the hydrogen-electricity coupling sub-model, and the flow rate of each pipeline is updated using the solution results.

[0122] Furthermore, the updated pipeline flow is passed to the hydrogen-electricity coupling sub-model, and the hydrogen-electricity coupling sub-model is re-solved to obtain a new operation strategy and operation cost.

[0123] It should be noted that when solving the heating sub-model, only the equipment and constraints related to heating and cooling need to be considered, and the required loads only include heat load data and cooling load data. At this time, the electricity used by each heating and cooling equipment comes from the power grid.

[0124] S304: Determine whether the current operation strategy is optimal: The difference between the current running cost and the running cost obtained in the previous iteration is divided by the current running cost to determine whether its absolute value is less than the set threshold.

[0125] If not, the operation strategy of the hydrogen energy equipment and the temperature of each heating pipeline in the solution are used to update the results in the previous iteration, and S3 is continued.

[0126] If so, it is considered that the current operation strategy reaches the economic optimum, the current operation cost is the minimum operation cost of the distributed integrated energy system, and the current operation strategy is output.

[0127] It should be noted that the final output results of the model specifically include: the flow rate of each pipeline at each moment; the power generation of photovoltaic panels in each energy station at each moment; the operating power and cooling capacity of electric chillers in each energy station at each moment; the operating power and heat generation of electric boilers in each energy station at each moment; the operating mode, operating power and heat or cooling capacity of each heat pump in each energy station at each moment; the operating power and hydrogen production of the electrolyzer in each energy station at each moment; the power generation, heat generation and hydrogen consumption of hydrogen fuel cells in each energy station at each moment; the capacity, storage capacity and hydrogen consumption of hydrogen storage tanks in each energy station at each moment; the capacity, storage capacity and power consumption of power storage units in each energy station at each moment; the inlet and outlet water temperatures of each energy storage tank at each moment; the inlet and outlet water temperatures of each energy station at each moment; the inlet and outlet water temperatures of each user area at each moment.

[0128] In another embodiment of the present invention, the present invention further provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device for storing programs and data. It is understandable that the computer-readable storage medium here may include both a built-in storage medium in a computer device and an extended storage medium supported by the computer device. The computer-readable storage medium provides a storage space, which stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by a processor are also stored in the storage space, and these instructions may be one or more computer programs (including program codes). It should be noted that the computer-readable storage medium here may be a high-speed RAM memory or a non-volatile memory, such as at least one disk memory. The processor may load and execute one or more instructions stored in the computer-readable storage medium to implement the corresponding steps of the optimization solution method of an optimization operation system of a distributed integrated energy in the above embodiment.

[0129] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0130] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any ordinary technician in the industry can smoothly implement the present invention as shown in the drawings and described above. However, any equivalent changes, modifications and evolutions made by technicians familiar with the profession without departing from the scope of the technical solution of the present invention using the technical content disclosed above are all equivalent embodiments of the present invention. At the same time, any equivalent changes, modifications and evolutions made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the technical solution of the present invention.

Claims

1. A method for establishing an optimized operation system of distributed integrated energy, characterized in that: include, Based on the internal operation structure of the distributed integrated energy system and the operation mechanism of each internal device, an internal device operation model is established to obtain the internal device operation constraints; Based on the heat loss of the heat medium in the heating pipeline, a heating network model of the pipeline heat transfer characteristics is established to obtain the heating network operation constraints; Based on the relationship between the supply and consumption of energy in the distributed integrated energy system, energy and heat balance constraints are obtained; An energy optimization model is established based on internal equipment operation constraints, heat network operation constraints, and energy and heat balance constraints; the energy optimization model includes a hydrogen-electricity coupling sub-model and a heat supply sub-model; Based on the internal equipment operation model, heat network model and energy optimization model, an optimized operation system of distributed integrated energy is obtained jointly.

2. The method for establishing a distributed integrated energy optimization operation system according to claim 1, characterized in that: The internal equipment operation constraints include: photovoltaic panel operation constraints, electric chiller operation constraints, electric boiler operation constraints, heat pump operation constraints, electrolyzer operation constraints, fuel cell operation constraints, power storage unit operation constraints, hydrogen storage tank operation constraints and energy storage water tank operation constraints; the heat network operation constraints include node flow balance constraints, node energy conservation constraints, pipeline water supply and return water temperature constraints and pipeline heat transfer characteristic constraints; The internal operation structure is an energy transmission system in which the energy station, the energy storage water tank and the user area are connected through a heating pipeline network.

3. The method for establishing a distributed integrated energy optimization operation system according to claim 1, characterized in that: The hydrogen-electricity coupling sub-model is established through the constraints of the heat network model, the internal equipment operation constraints, the energy balance constraints, and the heat constraints at the heat source end and the load end; the energy balance constraints include the electricity balance constraints and the cold and heat balance constraints.

4. The method for establishing a distributed integrated energy optimization operation system according to claim 1, characterized in that: The objective function of the hydrogen-electricity coupling sub-model is to minimize the cost of purchasing electricity and hydrogen. The specific formula is: in, is the number of energy stations, and They are the first The cost of purchasing electricity and hydrogen for each energy station.

5. The method for establishing a distributed integrated energy optimization operation system according to claim 1, characterized in that: The heating sub-model is established by the operation constraints of the heating network, the operation constraints of the heating and cooling related equipment in the internal equipment operation constraints, the cold and heat balance constraints, and the heat constraints at the heat source end and the load end; The operation constraints of the heating and cooling related equipment include electric boiler operation constraints, electric refrigerator operation constraints, heat pump operation constraints, water tank operation constraints and fuel cell operation constraints.

6. The method for establishing a distributed integrated energy optimization operation system according to claim 1, characterized in that: The objective function of the heating sub-model is to minimize the electricity purchase cost, and the specific formula is: in, is the number of energy stations, The first The electricity purchase cost of an energy station.

7. An optimized operation system of distributed integrated energy, obtained based on the method for establishing an optimized operation system of distributed integrated energy described in any one of claims 1-6.

8. The optimization solution method for the distributed integrated energy optimization operation system according to claim 7, characterized in that: include, Solve the hydrogen-electricity coupling sub-model to obtain the operation strategy and cost of the distributed integrated energy system, and transfer the operation strategy of the hydrogen energy equipment and the temperature of the heating pipeline to the heating sub-model as the initial conditions; Solve the heating sub-model, update the pipeline flow rate with the heat flow rate result obtained, and then feed the updated pipeline flow rate back to the hydrogen-electricity coupling sub-model, iteratively solve the hydrogen-electricity coupling sub-model until the optimal operation strategy and operation cost are obtained, specifically: Determine whether the ratio of the difference between the current operating cost of the distributed integrated energy system and the operating cost obtained in the previous iteration and the current operating cost is less than a preset threshold; If it is less than the preset threshold, the iteration is stopped, and the current operation strategy of the distributed integrated energy system is used as the economically optimal operation strategy, and the operation of the distributed integrated energy system is controlled by using this strategy; If it is not less than the preset threshold, the operation strategy of the hydrogen energy equipment in the current strategy is passed to the heating sub-model as the initial condition, and the iteration is continued until the economically optimal operation strategy is obtained.

9. An optimization solution system for an optimized operation system of distributed integrated energy, obtained based on the optimization solution method for an optimized operation system of distributed integrated energy described in claim 8.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by the processor, the steps of the optimization solution method for the optimized operation system of a distributed integrated energy source as described in claim 8 are implemented.

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