Comprehensive energy system optimal scheduling method considering thermal power plant carbon capture, medium and product

Abstract

The invention discloses a comprehensive energy system optimization scheduling method considering thermal power plant carbon capture, a medium and a product, and relates to the field of comprehensive energy system operation optimization, and the method comprises the steps: building an oxygen-enriched combustion capture-electricity-to-gas-oxygen storage tank coupling model, and introducing the coupling model into a comprehensive energy system; a carbon capture technology is selected according to the renewable energy surplus; introducing a reward and punishment type carbon transaction mechanism, and establishing an integrated energy system low-carbon economic dispatching model considering thermal power plant carbon capture by taking the minimum total operation cost of the integrated energy system as a target function; and carrying out optimal scheduling on the integrated energy system based on the low-carbon economic scheduling model of the integrated energy system. While the renewable energy consumption rate is improved, the economical efficiency of the comprehensive energy system can be improved, and the carbon emission of the comprehensive energy system is effectively reduced.

Description

Technical Field

[0001] The present application relates to the technical field of integrated energy system operation optimization, and in particular to an integrated energy system optimization scheduling method, medium and product taking into account carbon capture in thermal power plants. Background Art

[0002] In China, coal-fired power plants are the main source of greenhouse gas emissions, accounting for about half of the country's total emissions. Carbon capture technology and carbon trading mechanisms have become important means to achieve low-carbon operation of the integrated energy system. Oxygen-enriched combustion technology is a technology that increases the oxygen concentration during the combustion process to improve combustion efficiency and reduce pollutant emissions. It has high capture efficiency and low capture energy consumption, but there is a problem of high oxygen production costs.

[0003] At present, most of the power-to-gas equipment used in the optimized operation mode of the integrated energy system of thermal power plants replaces the air separation oxygen generator, which easily leads to the constraint of "electricity determined by oxygen", making it impossible for the integrated energy system to achieve optimal operation and failing to truly achieve the goal of reducing the cost of oxygen production. Summary of the invention

[0004] The purpose of this application is to provide an integrated energy system optimization scheduling method, medium and product taking into account carbon capture in thermal power plants, so as to improve the economic efficiency of the integrated energy system while increasing the renewable energy absorption rate and effectively reduce the carbon emissions of the integrated energy system.

[0005] To achieve the above objectives, this application provides the following solutions:

[0006] In a first aspect, the present application provides a method for optimizing the scheduling of an integrated energy system taking into account carbon capture in thermal power plants, comprising:

[0007] Establish a coupled model of oxygen-enriched combustion capture-power-to-gas-oxygen storage tank and introduce it into the integrated energy system;

[0008] Selecting a carbon capture technology based on the surplus of renewable energy; the carbon capture technology includes a post-combustion capture technology and an oxyfuel combustion capture technology; the oxyfuel combustion capture technology collects carbon dioxide based on the coupling model;

[0009] Introducing a reward-and-penalty carbon trading mechanism, taking the minimum total operating cost of the integrated energy system as the objective function, and establishing a low-carbon economic dispatch model for the integrated energy system taking into account carbon capture in thermal power plants;

[0010] The integrated energy system is optimized and scheduled based on the low-carbon economic scheduling model of the integrated energy system.

[0011] In a second aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of any of the above-mentioned methods for optimizing scheduling of an integrated energy system taking into account carbon capture in thermal power plants.

[0012] In a third aspect, the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the steps of any of the above-mentioned methods for optimizing scheduling of an integrated energy system taking into account carbon capture in thermal power plants.

[0013] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0014] (2) This application establishes a coupled model of oxygen-enriched combustion capture-power-to-gas-oxygen storage tank, in which the power-to-gas device and the air separation oxygen generator cooperate with the oxygen storage tank to provide oxygen-enriched conditions for the integrated energy system. This not only alleviates the load supply pressure of the thermal power plant, but also makes full use of the oxygen generated in the first stage of the power-to-gas conversion, thereby reducing the total operating cost of the integrated energy system.

[0015] (3) This application considers the surplus of renewable energy to select carbon capture technology. When the surplus of renewable energy is sufficient, post-combustion capture technology is selected, and when it is insufficient, oxygen-enriched combustion capture technology is selected, which further reduces the O2 demand and CO2 emissions of the integrated energy system and better realizes the low-carbon economic operation of the integrated energy system.

[0016] (3) This application establishes a low-carbon economic dispatch model for an integrated energy system that takes into account carbon capture in thermal power plants. Compared with traditional post-combustion capture technology, the total operating cost and carbon emissions of the integrated energy system that takes into account oxygen-enriched combustion capture are significantly reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a schematic diagram of the structural block diagram of the integrated energy system;

[0019] Figure 2 A flow chart of an integrated energy system optimization scheduling method taking into account carbon capture in thermal power plants provided in one embodiment of the present application;

[0020] Figure 3 It is the electric heat gas load curve;

[0021] Figure 4The wind and solar prediction curve is shown in Figure 2. (a) shows 1,000 photovoltaic and wind power generation scenarios, and (b) shows typical photovoltaic and wind power output scenarios.

[0022] Figure 5 is the oxygen power balance diagram;

[0023] Figure 6 This is the electrical load balance diagram. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0025] Power-to-gas can convert surplus electricity into chemical energy, and then into natural gas for storage, thus improving the consumption level of wind power. In addition, the oxygen produced in the first stage of power-to-gas is rarely used. Therefore, how to achieve the coupling of power-to-gas technology and oxygen-enriched combustion technology and integrate the coupling model into the low-carbon economic operation of the integrated energy system has great research significance and value.

[0026] At present, most of the power-to-gas equipment used in the optimized operation mode of the integrated energy system of oxygen-rich combustion power plants replaces the air separation oxygen generator, which easily leads to the constraint of "electricity determined by oxygen", making it impossible for the IES (integrated energy system) to achieve optimal operation and failing to truly achieve the goal of reducing the cost of oxygen production.

[0027] At present, electricity is the industry with the largest share of coal consumption and carbon emissions in China, accounting for more than 40% of carbon emissions. Oxygen-enriched combustion technology has high capture efficiency and low capture energy consumption, but there is a high oxygen production cost. This application mainly introduces oxygen-enriched combustion power plants into the integrated energy system to reduce the oxygen production cost in ensuring the low-carbon economic operation of the system. Figure 1 As shown, the present application adopts a power-to-gas device to combine the oxygen-enriched capture of a thermal power plant with an integrated energy system. The power-to-gas utilizes the surplus electricity of wind and solar power to produce oxygen and hydrogen, wherein the hydrogen is used for methanation and conversion into natural gas for supplying gas turbines and gas boilers; the oxygen is stored in an oxygen storage tank, which cooperates with the air separation oxygen generator to meet the oxygen demand in the oxygen-enriched combustion power plant, forming a combined operation mode of power-to-gas-oxygen-enriched combustion power plant-oxygen storage tank to achieve energy recycling.

[0028] like Figure 1As shown, the electric load is supplied by oxygen-rich combustion power plant (OCPP), wind power, photovoltaic power and battery, among which the oxygen-rich combustion power plant (OCPP) includes thermal power plant and gas turbine (GT); the thermal load is supplied by gas boiler (GB), gas turbine (GT), electric boiler and heat storage tank; the gas load is supplied by gas grid, power-to-gas (P2G) and methane storage device.

[0029] During the period when the output of renewable energy (wind and light) is sufficient, the excess electricity can be: 1. stored; 2. converted into heat energy through electric boilers; 3. electrolyzed into hydrogen and oxygen through the P2G electrolyzer, where hydrogen undergoes methanation reaction to generate methane to supply gas load and gas units, and oxygen is supplied to oxygen-enriched combustion power plants (OCPPs). The oxygen produced by P2G and the air separation oxygen generator (ASU) cooperate with oxygen storage tanks to meet the oxygen demand of oxygen-enriched combustion power plants. When renewable energy is in surplus, post-combustion capture technology is used, and P2G and ASU produce oxygen for storage; when the output of renewable energy is insufficient, oxygen-enriched combustion capture technology is used, and the oxygen demand increases. At this time, the oxygen storage tank releases oxygen to reduce the load. During the period when the output of renewable energy (wind and light) is insufficient, it is necessary to release the energy of the energy storage device and increase the output of each unit to meet the demand for electric heat and gas loads.

[0030] This application proposes an operation mode in which power-to-gas participates in carbon capture in thermal power plants, and is divided into two operation modes: post-combustion capture and oxygen-enriched combustion capture according to the surplus of renewable energy. First, the oxygen produced by the power-to-gas and air separation oxygen generator is supplied to the oxygen-enriched combustion power plant. The carbon dioxide captured by the oxygen-enriched combustion power plant is used as the raw material for the power-to-gas methanation reaction, and the generated natural gas is supplied to the gas unit to achieve full utilization of energy; at the same time, an oxygen storage tank is introduced to solve the problem of mismatch between the production and use time of O2 in the two operation modes.

[0031] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0032] In an exemplary embodiment, Figure 2 As shown, a method for optimizing the scheduling of an integrated energy system taking into account carbon capture in thermal power plants is provided. The method is executed by a computer device, and can be executed by a computer device such as a terminal or a server alone, or by a terminal and a server together. In the embodiment of the present application, the method is applied to a server as an example for explanation, and includes the following steps S1 to S4. Among them:

[0033] S1: Establish a coupled model of oxygen-enriched combustion capture-power-to-gas-oxygen storage tank and introduce it into the integrated energy system.

[0034] S2: Select carbon capture technology based on the surplus of renewable energy; the carbon capture technology includes post-combustion capture technology and oxygen-enriched combustion capture technology; the oxygen-enriched combustion capture technology performs carbon dioxide capture based on the coupling model.

[0035] S3: Introduce a reward-and-penalty carbon trading mechanism, take the minimization of the total operating cost of the integrated energy system as the objective function, and establish a low-carbon economic dispatch model for the integrated energy system that takes into account carbon capture in thermal power plants.

[0036] S4: Optimize the scheduling of the integrated energy system based on the low-carbon economic scheduling model of the integrated energy system.

[0037] In a specific embodiment, step S1 specifically includes:

[0038] The traditional carbon capture device is transformed into an oxygen-enriched carbon capture device. The oxygen demand is met by P2G (electrolyzer) and ASU (air separation oxygen generator) in conjunction with an oxygen storage tank. A coupling model of oxygen-enriched combustion capture-power-to-gas-oxygen storage tank is established and introduced into the integrated energy system. The traditional carbon capture device is transformed into an oxygen-enriched combustion capture device. The oxygen-enriched conditions are provided by using the O2 generated by P2G and the oxygen generator in conjunction with the oxygen storage tank, which can effectively reduce the oxygen energy consumption of oxygen-enriched combustion capture.

[0039] The coupling model is a model obtained by coupling the power-to-gas model, the oxygen storage tank model and the carbon capture model of the thermal power plant.

[0040] The power-to-gas model is shown in formula (1):

[0041]

[0042] Where: are the amount of hydrogen and oxygen produced by water electrolysis from power-to-gas conversion, respectively; η EL is the conversion efficiency of the electrolyzer; P EL is the input power of the electrolyzer; H g is the calorific value of hydrogen.

[0043] The oxygen storage tank model is shown in formula (2):

[0044]

[0045] Where: is the storage capacity of the oxygen storage tank at time t and time t-1; are the efficiency of the oxygen storage tank in storing and releasing oxygen, respectively; are the amount of oxygen stored and released at time t respectively; They are the upper and lower limits of oxygen storage at time t respectively; They are the upper and lower limits of oxygen release at time t respectively; is the storage capacity of the oxygen tank at the initial time t0; is the storage capacity of the oxygen tank at the final moment T.

[0046] The carbon capture model of thermal power plants is shown in formula (3):

[0047]

[0048] Where: P B is the total power generation of the thermal power plant; is the power generation capacity of the gas turbine; P ASU P is the power required by the air separation oxygen generator; CCS1 , P CCS2 are the carbon capture power consumption of thermal power plants and gas turbines respectively; P N1 , P N2 are the net output power of the unit and gas turbine respectively; P N is the total net output power of the thermal power plant.

[0049] The power consumption of carbon capture in thermal power plants can be expressed by formula (4):

[0050]

[0051] Where: μ CO2 , η CCS , CO2 They are the amount of carbon dioxide emitted per unit power (valued at 1.08 (t / MW·h)), the capture efficiency of oxygen-enriched combustion, and the energy consumption per unit of carbon dioxide captured (valued at 0.0893 (MW·h / t)); are the carbon dioxide emissions and capture amounts of thermal power plants, respectively.

[0052] Similarly, the carbon capture power consumption of the gas turbine can be obtained as P CCS2 and the total carbon capture power consumption P CCS :

[0053]

[0054] By coupling formula (1)-formula (3), the coupling model of oxygen-enriched combustion capture-electric-to-gas-oxygen storage tank can be obtained. The coupling model is shown in formula (6):

[0055]

[0056] Where: are the total amount of oxygen required by the thermal power plant, the amount of oxygen produced by the air separation oxygen generator, the amount of oxygen produced by the power-to-gas electrolysis of water, and the amount of oxygen supplied by the oxygen storage tank; χ is the amount of oxygen required per unit power of the thermal power plant with oxygen-enriched fuel consumption, which is 600, m 3 / MW; The unit oxygen energy consumption of the air separation oxygen generator is 0.303, kW·h / m 3 .

[0057] The mathematical models of other equipment in the integrated energy system are as follows:

[0058] The gas turbine model is shown in formula (7):

[0059]

[0060] Where: They are the electrical and thermal power output of GT (gas turbine) respectively; is the electrical and thermal conversion efficiency of GT; They are the upper and lower limits of GT power generation respectively; k1, k2, k3 are the electric-thermal conversion efficiencies of GT, all of which are 0.4.

[0061] The electric boiler model is shown in formula (8):

[0062]

[0063] Where: are the output thermal power and input electrical power of EB (electric boiler) respectively; η EB is the energy conversion efficiency of EB.

[0064] The renewable energy unit model is shown in formula (9):

[0065]

[0066] Where: P W , P V Forecast output for wind power and photovoltaic power; It is the actual wind power and photovoltaic power output; It is the abandoned wind and solar power; Abandon wind and solar power to supply electrolyzer power.

[0067] The gas boiler model is shown in formula (10):

[0068]

[0069] Where: P GB is the output thermal power of GB (gas boiler); η GB is the efficiency of GB; is the amount of methane consumed by GB; The energy produced by the combustion of unit methane.

[0070] The model of the electric and thermal storage equipment is shown in formula (11):

[0071]

[0072] Where: S ES,t , S HS,t are the storage capacity of the electricity storage and heat storage equipment at time t; S ES,t-1 , S HS,t-1 are the storage capacities of the electricity storage and heat storage equipment at time t-1 respectively; are the charging and discharging efficiency of the storage battery respectively; are the charging and discharging power of the battery respectively; are the charging and discharging heat efficiencies of the heat storage tank respectively; are the charging and discharging heat powers of the heat storage tank respectively.

[0073] In a specific embodiment, step S2 specifically includes:

[0074] In order to further reduce oxygen energy consumption, two operating modes are proposed: post-combustion capture and oxygen-enriched combustion capture. When the surplus of renewable energy is greater than 0 (when wind power and photovoltaic power are not fully used), the output of the thermal power plant is the smallest, and CO2 emissions are relatively low at this time, so the carbon capture system adopts post-combustion capture technology; when the surplus of renewable energy is less than 0 (when wind power and photovoltaic power output are lower than the electrical load), the output of thermal power will increase, and CO2 emissions are relatively high at this time, so the carbon capture system adopts oxygen-enriched combustion capture technology. The two operating modes cooperate with each other to reasonably capture CO2, achieving a low-carbon effect while reducing oxygen energy consumption.

[0075] Enter the parameters of each device in IES, as shown in Table 1:

[0076] Table 1

[0077] Parameter Type Thermal Power Plant P2G GT GB EB TES EES Power ceiling / MW 40 30 40 30 10 10 10 Power lower limit / MW 0 0 10 5 0 0 0 Unit capacity / MW - - - - - 50 50 Ramp rate / MW 20 15 20 20 10 - - efficiency 0.98 0.8 0.9 0.9 0.9 0.95 0.95

[0078] Calculate the surplus of renewable energy. The surplus of renewable energy is determined by the predicted output of wind turbines and photovoltaics, the predicted load, and the output of oxygen-enriched units, as shown in formula (12):

[0079]

[0080] Where: ΔP t is the surplus of renewable energy at time t; are the minimum output power of the thermal power plant and gas turbine at time t respectively; is the wind power and photovoltaic output power at time t; is the electrical load at time t.

[0081] (1) Post-combustion capture technology:

[0082] Determine whether formula (12) satisfies the following formula:

[0083] ΔPt ≥0(13)

[0084] Under this condition, there is surplus electricity in the renewable energy units, and even if other generators in the IES are reduced to the minimum output, it cannot be completely absorbed, resulting in the problem of wind and solar power abandonment and resource waste. Under this scheduling mode, the generator output is the lowest, and the amount of CO2 it produces is the least. At this time, the carbon capture system adopts post-combustion capture technology, which can effectively reduce the system's oxygen production energy consumption and operating costs while maintaining low carbon emissions; at the same time, the surplus renewable electricity is supplied to P2G, and H2 and O2 are produced in the water electrolysis stage, of which H2 undergoes methanogenic reaction to generate methane to supply gas load, and O2 is stored in the oxygen storage tank to meet the oxygen demand at the time of oxygen-enriched combustion capture scheduling.

[0085] (2) Oxygen-enriched combustion capture technology:

[0086] Determine whether formula (12) satisfies the following formula:

[0087] ΔP t <0(14)

[0088] Under this condition, the load is at the peak and valley period, and the output of renewable energy units can be fully absorbed. At this time, the output of wind turbines and photovoltaics alone can no longer meet the system's electrical load requirements, and other generators need to increase their output. If the carbon capture system continues to use post-combustion capture technology, it will cause higher capture costs and a large amount of CO2 emissions. Therefore, it is considered to supply oxygen in the oxygen storage tank to the thermal power plant for oxygen-enriched combustion capture technology to reduce the ASU oxygen production power. At this time, the thermal power plant consumes a lower capture cost to efficiently capture the CO2 emitted by the generator set and achieve the low-carbon nature of the integrated energy system.

[0089] In a specific embodiment, step S3 specifically includes:

[0090] Introducing a reward-and-penalty carbon trading mechanism based on steps S1-S2 can further constrain the carbon emissions of the integrated energy system. Finally, taking the sum of the operation and maintenance costs of each device in the integrated energy system, the penalty costs for wind and solar power abandonment, the carbon trading costs, and the energy purchase costs as the minimum objective function, a low-carbon economic dispatch model for the integrated energy system taking into account carbon capture in thermal power plants is established.

[0091] (I) The objective function is shown in formula (15):

[0092] F=min{F op +F q +F co2 +F buy}(15)

[0093] Where: F is the total operating cost of the integrated energy system, including the following parts: the operating and maintenance cost of each device Fop , Penalty cost for wind and solar curtailment F q , Carbon trading costs F co2 and the energy purchase cost F buy .

[0094] The operation and maintenance cost is shown in formula (16):

[0095]

[0096] Where: i∈Ω={P2G,CCS,GB,GT,EB,ASU}; T is the time scale, which is 24h; They are equipment startup and shutdown and maintenance cost coefficients respectively; is a binary variable, indicating the operating status of the equipment; t i is the power of the unit at time t; are the cost coefficients of natural gas storage, oxygen storage tanks, batteries and heat storage tanks respectively.

[0097] The energy purchase cost is shown in formula (17):

[0098]

[0099] Where: F gas 、F g are the cost of purchasing natural gas and the fuel cost of thermal power plants respectively; a, b, c are the energy consumption parameters of thermal power plants; P B,t is the total power generated by the thermal power plant; C gas is the price of purchasing a unit of natural gas; Q GT,t , Q GB,t , Q P2G,t are the natural gas consumed by GT, GB and generated by P2G; Q L,t is the gas load at time t.

[0100] The penalty cost for wind and solar power abandonment is shown in formula (18):

[0101]

[0102] Where: C cf Cutting penalty factors for renewable energy; They are the reduced power of wind power and photovoltaic power respectively.

[0103] The carbon trading cost is shown in formula (19):

[0104]

[0105] Where: β is the carbon dioxide emission and carbon emission intensity of the heat generating units; is the carbon trading market cost coefficient; It is the carbon dioxide emitted by thermal power plants after carbon capture; A and B are the carbon emission quotas per unit power of electricity and heat respectively.

[0106] (II) The constraints of the low-carbon economic dispatch model of the integrated energy system include: electric power balance constraints, thermal power balance constraints, gas power balance constraints, upper and lower limits of unit output power constraints, and unit power ramp constraints. The constraints are as follows:

[0107] The electric power balance constraint is shown in formula (20):

[0108]

[0109] In the formula, is the net output power of the thermal power plant at time t; is the wind power output at time t; is the photoelectric output at time t; The battery discharge at time t; is the electrical load at time t; The power consumption of the electric boiler at time t; is the power consumption of the carbon capture device at time t; The battery stores electricity at time t; is the electrical load at time t.

[0110] The thermal power balance constraint is shown in formula (21):

[0111]

[0112] In the formula, is the heat generation power of the gas turbine at time t; is the heating power of the gas boiler at time t; is the heating power of the electric boiler at time t; is the heat release power of the heat storage tank at time t; is the heat storage power of the heat storage tank at time t; is the heat load at time t.

[0113] The gas power balance constraint is shown in formula (22):

[0114] Q P2G,t +Q BUY,t =Q GT,t +Q GB,t +Q L,t (twenty two)

[0115] In the formula, Q P2G,t Q is the amount of natural gas produced by power-to-gas conversion at time t; BUY,t Q is the amount of natural gas purchased at time t; GT,tis the natural gas consumption of the gas turbine at time t; Q GB,t is the amount of natural gas consumed by the gas boiler at time t; Q L,t is the gas load at time t.

[0116] The upper and lower limits of the unit output power are shown in formula (23):

[0117] u i,t P i,min ≤P i,t ≤u i,t P i,max (twenty three)

[0118] Where: i∈{P2G,ASU,GT,GB,EB}, P i,max , P i,min are the maximum and minimum output power of unit i respectively.

[0119] The unit power ramp constraint is shown in formula (24):

[0120]

[0121] Where: are the maximum upward and downward climbing powers of unit i respectively.

[0122] In a specific embodiment, the nonlinear integer model is converted into a mixed integer linear model using a piecewise linearization method, and the SCIP solver in MATLAB is called to solve it, and the integrated energy system is optimized and scheduled according to the optimal solution.

[0123] In order to verify the feasibility of the integrated energy system optimization scheduling method proposed in this application with consideration of carbon capture in thermal power plants, a certain integrated energy system is selected as the research object, and its electric, thermal, gas load and wind and solar forecast data are as follows: Figure 3 , Figure 4 As shown, the following five scenarios are set for comparative analysis:

[0124] Scenario 1: Considering post-combustion capture technology but not considering P2G devices;

[0125] Scenario 2: Considering oxygen-enriched combustion capture technology, ignoring P2G devices;

[0126] Scenario 3: Considering post-combustion capture technology, P2G devices and energy storage equipment;

[0127] Scenario 4: Considering oxygen-enriched combustion capture technology, P2G devices and energy storage equipment;

[0128] Scenario 5: Considering two operating modes, post-combustion capture technology and oxyfuel combustion capture technology, P2G device and energy storage equipment.

[0129] Table 2 shows the total system operating costs and carbon emissions under five different scenarios:

[0130] Table 2

[0131]

[0132]

[0133] From Table 2, we can see that the total operating cost of scenario 1 is the highest, 555,191 yuan, and the total operating cost of scenario 5 is the lowest, 323,555 yuan. Compared with scenario 3, scenario 4 takes into account the oxygen-enriched combustion capture technology. Although the thermal power cost and operation and maintenance cost increase by 11.93% and 2.11%, the carbon trading cost brought by the efficient capture capacity increases by 34.12%, the total operating cost is reduced by 20,946 yuan, and the carbon emissions are reduced by 86.65 tons, which reflects that the integrated energy system can reduce carbon emissions while ensuring low operating costs. Compared with Scenario 4, Scenario 5 comprehensively considers oxygen-enriched combustion capture technology and post-combustion capture technology. Although carbon emissions increased by 5.81 tons, the thermal power cost, operation and maintenance cost, and carbon sequestration cost were reduced by 2,179 yuan, 1,818 yuan, and 481 yuan, respectively. When the wind and solar power outputs are sufficient, the integrated energy system uses post-combustion capture technology to reduce the oxygen production cost and the maintenance cost of each unit. When the wind and solar power outputs are insufficient, oxygen-enriched combustion capture technology is used. The increased output of the unit will release a large amount of CO2. At this time, the efficient capture capacity can achieve low-carbon operation of the integrated energy system and reap high carbon trading costs.

[0134] Depend on Figure 5 It can be seen that the oxygen storage tank stores the oxygen produced by P2G during the post-combustion capture technology period and releases oxygen during the oxygen-enriched combustion capture technology period. The total amount of oxygen produced by P2G accounts for about 12.65% of the total oxygen consumption of the system, indicating that the P2G water electrolysis stage can reduce the dependence of the oxygen-enriched combustion capture technology on the air separation oxygen generator to a certain extent. The oxygen demand in scenario 4 is 79577m more than that in scenario 5. 3 It can be seen that scenario 5 using two scheduling modes can effectively reduce the oxygen demand and reduce the energy consumption of oxygen production. In summary, the power-to-gas-oxygen-enriched combustion power plant-oxygen storage tank combined oxygen supply operation mode can reduce the energy consumption of the comprehensive energy system and realize the load transfer of the oxygen-enriched combustion power plant. The combination of the two scheduling modes can significantly reduce the oxygen load.

[0135] The power dispatch results are as follows: Figure 6 As shown, the renewable energy surplus ΔP during the period 1:00-5:00 t ≥0, using post-combustion capture technology, powered by wind power, gas turbines and power storage equipment, and using excess power for P2G devices to produce oxygen and methane; during the 6:00-11:00 period, the surplus of renewable energy ΔPt <0, using oxygen-enriched combustion capture technology, during this period, the demand for electricity load increases, photovoltaic and thermal power plants begin to supply electricity; during the 12:00-14:00 period, the surplus of renewable energy ΔP t ≥0, using post-combustion capture technology, the photovoltaic output reaches the maximum, and the wind power, photovoltaic, gas turbine and power storage equipment jointly supply power, and the excess power is used for P2G devices; during the period of 15:00-22:00, the surplus of renewable energy ΔP t <0, using oxygen-enriched combustion capture technology, the photovoltaic output gradually decreases, and the power supply from gas turbines and thermal power plants meets the power balance; during the 23:00-24:00 period, the surplus of renewable energy ΔP t ≥0, adopt post-combustion capture technology, wind power gradually increases, so the output of thermal power is reduced, and the surplus electricity is used for P2G devices.

[0136] In an exemplary embodiment, a computer-readable storage medium is provided, storing a computer program, and when the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0137] In an exemplary embodiment, a computer program product is provided, including a computer program, and when the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0138] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0139] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM may be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0140] The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. The non-relational database may include a distributed database based on blockchain, etc., but is not limited thereto. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but is not limited thereto.

[0141] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0142] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A method for optimizing the dispatch of an integrated energy system taking into account carbon capture in thermal power plants, characterized in that: include: Establish a coupled model of oxygen-enriched combustion capture-power-to-gas-oxygen storage tank and introduce it into the integrated energy system; Selecting a carbon capture technology based on the surplus of renewable energy; the carbon capture technology includes a post-combustion capture technology and an oxyfuel combustion capture technology; the oxyfuel combustion capture technology collects carbon dioxide based on the coupling model; Introducing a reward-and-penalty carbon trading mechanism, taking the minimum total operating cost of the integrated energy system as the objective function, and establishing a low-carbon economic dispatch model for the integrated energy system taking into account carbon capture in thermal power plants; The integrated energy system is optimized and scheduled based on the low-carbon economic scheduling model of the integrated energy system.

2. The method for optimizing the dispatch of an integrated energy system taking into account carbon capture in thermal power plants according to claim 1, characterized in that: The coupling model is a model obtained by coupling a power-to-gas model, an oxygen storage tank model and a thermal power plant carbon capture model.

3. The method for optimizing the dispatching of an integrated energy system taking into account carbon capture in thermal power plants according to claim 2, characterized in that: The expression of the power-to-gas model is: in, are the amount of hydrogen and oxygen produced by water electrolysis from power-to-gas conversion, respectively; η EL is the conversion efficiency of the electrolyzer; P EL is the input power of the electrolyzer; H g is the calorific value of hydrogen; The oxygen storage tank model expression is: in, are the storage capacity of the oxygen storage tank at time t and time t-1 respectively; are the efficiency of the oxygen storage tank in storing and releasing oxygen, respectively; are the amount of oxygen stored and released at time t respectively; are the minimum and maximum values ​​of the oxygen tank storage capacity respectively; are the lower and upper limits of oxygen storage respectively; are the lower and upper limits of oxygen release, respectively; is the storage capacity of the oxygen tank at the initial time t0; is the storage capacity of the oxygen tank at the final moment T; The carbon capture model expression of the thermal power plant is: Among them, P B is the total power generation of the thermal power plant; is the power generation capacity of the gas turbine; P N is the total net output power of the thermal power plant; P ASU P is the power required by the air separation oxygen generator; CCS1 , P CCS2 are the carbon capture power consumption of thermal power plants and gas turbines respectively; P N1 , P N2 are the net output power of the unit and the gas turbine respectively.

4. The method for optimizing the dispatching of an integrated energy system taking into account carbon capture in thermal power plants according to claim 2, characterized in that: The expression of the coupling model is: in, are the total amount of oxygen required by the thermal power plant, the amount of oxygen produced by the air separation oxygen generator, the amount of oxygen produced by the power-to-gas electrolysis of water, and the amount of oxygen supplied by the oxygen storage tank; χ is the amount of oxygen required per unit power of combustion capture; P is the energy consumption per unit of oxygen produced by the air separation oxygen generator; B is the total power generation of the thermal power plant; is the power generation capacity of the gas turbine; P ASU The power required for the air separation oxygen generator.

5. The method for optimizing the dispatch of an integrated energy system taking into account carbon capture in thermal power plants according to claim 1, characterized in that: Select carbon capture technologies based on the amount of renewable energy surplus, including: Calculate renewable energy surplus; When the renewable energy surplus is greater than or equal to 0, post-combustion capture technology is selected; When the surplus of renewable energy is less than 0, oxygen-enriched combustion capture technology is selected.

6. The method for optimizing the dispatch of an integrated energy system taking into account carbon capture in thermal power plants according to claim 5, characterized in that: The calculation formula for the renewable energy surplus is: Among them, ΔP t is the surplus of renewable energy at time t; are the minimum output power of the thermal power plant and gas turbine at time t respectively; is the wind power output power and photovoltaic output power at time t; is the electrical load at time t.

7. The method for optimizing the dispatch of an integrated energy system taking into account carbon capture in thermal power plants according to claim 1, characterized in that: The objective function of the low-carbon economic dispatch model of the integrated energy system is: F=min{F op +F q +F co2 +F buy } Where F is the total operating cost of the integrated energy system; F op is the operation and maintenance cost of each equipment in the integrated energy system; F q F is the penalty cost of wind and solar power abandonment for each device in the integrated energy system; co2 is the carbon trading cost of each device in the comprehensive energy system; F buy It is the energy purchase cost of each equipment in the comprehensive energy system.

8. The method for optimizing the dispatch of an integrated energy system taking into account carbon capture in thermal power plants according to claim 1, characterized in that: The constraints of the low-carbon economic dispatch model of the integrated energy system include: electric power balance constraints, thermal power balance constraints, gas power balance constraints, upper and lower limit constraints of unit output power, and unit power ramp constraints; The expression of the electric power balance constraint is: in, is the net output power of the thermal power plant at time t; is the wind power output at time t; is the photoelectric output at time t; The battery discharge at time t; is the electrical load at time t; The power consumption of the electric boiler at time t; is the power consumption of the carbon capture device at time t; The battery stores electricity at time t; is the electrical load at time t; The expression of thermal power balance constraint is: in, is the heat generation power of the gas turbine at time t; is the heating power of the gas boiler at time t; is the heating power of the electric boiler at time t; is the heat release power of the heat storage tank at time t; is the heat storage power of the heat storage tank at time t; is the heat load at time t; The expression of gas power balance constraint is: Q P2G,t +Q BUY,t =Q GT,t +Q GB,t +Q L,t Among them, Q P2G,t Q is the amount of natural gas produced by power-to-gas conversion at time t; BUY,t Q is the amount of natural gas purchased at time t; GT,t is the natural gas consumption of the gas turbine at time t; Q GB,t is the amount of natural gas consumed by the gas boiler at time t; Q L,t is the gas load at time t; The expression of the upper and lower limits of the unit output power is: u i,t Q i,min ≤P i,t ≤u i,t Q i,max Where i∈{P2G,ASU,GT,GB,EB}; P2G is the electrolyzer; ASU is the air separation oxygen generator; GT is the gas turbine; GB is the gas boiler; EB is the electric boiler; P i,max , P i,min are the maximum output power and minimum output power of unit i respectively; The expression of the unit power ramp constraint is: in, are the maximum upward climbing power and downward climbing power of unit i respectively.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for optimizing the scheduling of an integrated energy system taking into account carbon capture in thermal power plants as described in any one of claims 1 to 8 are implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method for optimizing the scheduling of an integrated energy system taking into account carbon capture in thermal power plants as described in any one of claims 1 to 8 are implemented.

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