Optimized operation method of electric heating comprehensive energy system considering fuel gas hydrogen doping and photo-thermal power station

Abstract

An electric heating comprehensive energy system optimized operation method considering gas hydrogen doping and a photo-thermal power station comprises the steps that a gas hydrogen doping technology is combined in a thermoelectric comprehensive energy system, and a gas hydrogen doping combined heat and power generation unit model is constructed; under the guidance of a time-of-use electricity price mechanism, the fuel gas hydrogen-doped combined heat and power generation unit is matched to supply energy to users; based on heat energy transmission characteristics of a waste heat recovery device, waste heat of the gas unit is recovered to a heat storage system of the photo-thermal power station, and a photo-thermal power station-gas hydrogen-doped cogeneration unit collaborative operation model is established; setting different comparison scenes by taking the lowest total cost of system operation as an optimization target, and establishing an electric heating integrated energy system optimization scheduling model; and performing simulation analysis under the condition of meeting the constraint of the electric heating comprehensive energy system to obtain the optimal output of each device in each time period in the electric heating comprehensive energy system. According to the method, the synergistic effect of the fuel gas hydrogen doping technology and the photo-thermal power station is comprehensively considered, the thermoelectric matching degree of the system is improved, new energy consumption can be effectively promoted, and the system operation economic benefits are improved.

Description

Technical Field

[0001] The present invention relates to the field of comprehensive energy optimization and scheduling, and in particular to a method for optimizing the operation of an electric-thermal comprehensive energy system taking into account hydrogen blending of natural gas and a solar thermal power station. Background Art

[0002] Large-scale wind and solar grid connection has strong volatility and intermittency. How to establish a more stable, flexible and low-carbon new energy structure system and improve the efficiency of new energy utilization is a technical challenge that urgently needs to be overcome.

[0003] The diversified utilization of hydrogen energy is an ideal carrier for realizing the large-scale development and utilization of new energy. However, the current immature hydrogen transportation technology restricts the development of hydrogen energy. The use of mixed hydrogen and natural gas technology to inject hydrogen produced by electric hydrogen production into natural gas pipelines provides the possibility for large-scale consumption of hydrogen energy and long-distance economic transportation. On the other hand, solar thermal power generation technology is a new form of power generation that can realize the "light-heat-electricity" energy conversion. Solar thermal power stations have the ability to operate continuously for a long time and can achieve continuous and stable power generation. Compared with conventional thermal power units, they have better regulation characteristics, fast climbing rate, short start-stop time and other advantages. At the same time, the heat storage system with higher capacity value not only has the advantages of longer life and lower cost, but also can effectively ensure the output stability and operation continuity of solar thermal power stations.

[0004] Existing research rarely uses gas-hydrogen blending technology in comprehensive energy, and there is no in-depth research on the problem of coordinated output of hydrogen-blended gas units and solar thermal power plants in actual operation. Therefore, it is of great significance to study the electric-thermal comprehensive energy system of gas-hydrogen blending units and solar thermal power plants. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides an optimization operation method of an electric and thermal integrated energy system considering gas hydrogen blending and solar thermal power stations. The method comprehensively considers the synergistic effect of gas hydrogen blending technology and solar thermal power stations to improve the thermal and electric matching degree of the system, which can effectively promote the consumption of new energy and improve the economic benefits of system operation.

[0006] The technical solution adopted by the present invention is:

[0007] The optimized operation method of the electric-thermal integrated energy system considering gas-hydrogen blending and a solar thermal power station comprises the following steps:

[0008] Step 1: Combine gas-hydrogen blending technology in the thermal power integrated energy system to build a gas-hydrogen blending cogeneration unit model;

[0009] Step 2: Through the electric-heat conversion characteristics of the electric heater, under the guidance of the time-of-use electricity price mechanism, the gas-hydrogen-blended cogeneration unit is used to supply energy to users;

[0010] Step 3: Considering the operation characteristics of the CSP power station participating in energy supply, and based on the heat energy transmission characteristics of the waste heat recovery device, the waste heat of the gas unit is recovered to the CSP power station heat storage system, and a collaborative operation model of the CSP power station-gas-hydrogen-blended cogeneration unit is established;

[0011] Step 4: Taking the lowest total system operation cost as the optimization goal, set 4 different comparison scenarios and establish an optimization scheduling model for the electric-thermal integrated energy system;

[0012] Step 5: Under the condition of satisfying the constraints of the electric-thermal integrated energy system, the YALMIP programming language and CPLEX solving software are used to perform simulation analysis to obtain the optimal output of each device in each period of the electric-thermal integrated energy system.

[0013] In step 1, the model of the gas-hydrogen mixed heat and power cogeneration unit is established as follows:

[0014] 1) Hydrogen-blended gas turbine model:

[0015]

[0016]

[0017] Where: P GT,g (t) are the natural gas and hydrogen power input to the hydrogen-blended gas turbine during period t; R GT (t) is the hydrogen blending ratio of the gas turbine during period t; are the calorific values ​​of hydrogen and natural gas respectively; P GT,e (t), P GT,h (t) are the electrical and thermal power output of the hydrogen-blended gas turbine during the period t; η GT,e , η GT,h They are the electrical and thermal conversion efficiencies of the hydrogen-blended gas turbine, respectively.

[0018] 2) Electrolyzer model:

[0019]

[0020] Where: is the hydrogen production power of the electrolyzer in time period t; is the hydrogen production of the electrolyzer in time period t; is the molar mass of hydrogen; is the hydrogen density; △t represents the scheduling period.

[0021] 3) Carbon capture equipment model:

[0022]

[0023]

[0024] Where: P CCS,e (t) is the electrical power supplied to the carbon capture equipment; P GT,e represents the electric power output of the gas turbine during the period t; P CCS,e1 (t), P CCS,e2 (t) are the fixed power loss and the CO 2 The electrical power consumed; CO captured by carbon capture equipment 2 Total amount; is the CO of the CHP unit in period t 2 Emissions; GT is the unit carbon emission intensity; CCS The energy required for carbon capture equipment to capture a unit of CO2; μ CCS for carbon capture efficiency; CO2 for carbon capture and storage 2 quantity; CO2 for power-to-gas plants for carbon capture 2 quantity.

[0025] 4) Methane reactor model:

[0026]

[0027]

[0028] Where: P MR,g (t) are the hydrogen power input into the methane reactor and the natural gas power output from the methane reactor in time period t; are the amount of hydrogen participating in the methane reaction and the amount of natural gas generated by the methane reactor in time period t, respectively; η MR,g is the conversion efficiency of the methane reactor in time period t; is the molar mass of natural gas; is the density of natural gas.

[0029] In step 2, an electric heater model is established:

[0030] Q EH (t) = P EH (t)η ah (8);

[0031] Where: Q EH (t) and P EH (t) are the heating power and power consumption of the electric heater in time period t; η ah It is the electric-heat conversion efficiency of the electric heater.

[0032] The electric-to-heat conversion characteristic of the electric heater is specifically that the electric heater can convert the surplus electric energy in the system or the electric energy purchased from the external power grid into thermal energy, which is used to provide the required heat load to the user.

[0033] Under the guidance of the time-of-use electricity price mechanism, the gas-hydrogen blending unit is used to supply energy to users, as follows:

[0034] During the full-day operation of the power grid, the purchase price of electricity is more expensive during peak electricity consumption periods and cheaper during low electricity consumption periods. Under the time-of-use electricity price mechanism, the electricity load will be reduced during high electricity price periods and transferred to low electricity price periods, realizing "peak shaving and valley filling", which can improve the economy of the system. Electric heaters need to consume electricity to provide heat. The electricity price is relatively cheap during the low electricity load period. At the same time, the gas-hydrogen blending unit in the system produces excess electricity. The electric heater can significantly improve the economy of the system by using this electricity, and also relieve the pressure of heat supply. The time-of-use electricity price of the power grid is shown in Table 1 below:

[0035] Table 1 Grid time-of-use electricity price

[0036]

[0037] In step 3, the operating characteristics of the CSP power station participating in energy supply are considered, as follows:

[0038] A CSP power station is an indirect solar thermal power generation system, which consists of three parts: a concentrating collector system (SF), a heat storage system (TES) and a power generation system (PB). The flow and conversion of energy between the parts is achieved through heat transfer fluid. The light field concentrates solar radiation onto the receiver through a reflector, and the collector uses the received solar energy to heat the heat transfer fluid (HTF) to complete the conversion of light energy into heat energy. Due to the ability to transmit and exchange heat, the CSP power station can not only transfer the obtained heat to the power generation system to generate electricity, but also transfer the heat to the heat network through the heat storage system to participate in the system's heat load supply. When the light intensity is high, the CSP power station stores the excess heat. During the peak period of electric and thermal load, the CSP power station increases the power generation power by calling the heat stored in the heat storage system, and translates the heat collected by the light field, making the CSP power station have a certain degree of dispatchability. Figure 2 Schematic diagram of the internal energy flow of the combined waste heat recovery device of the solar thermal power station.

[0039] In step 3, a CSP power plant model that operates in coordination with a gas-hydrogen-blended cogeneration unit is established, including:

[0040] 1) The model of waste heat recovery device is:

[0041]

[0042] Where: P HRD(t) represents the heat power of the device recovery system in time period t; η HRD Indicates the operating efficiency of the recovery device; P HRD，max Indicates the maximum heat power of the device recovery system; It represents the heating power supplied by the CHP unit to the HRD during period t;

[0043] 2) Concentrating solar collector system model:

[0044] Q S-H (t) = η SF S SF D solar (t)-Q cur (t)(10);

[0045] Where: Q S-H (t) is the heat power transmitted from the mirror field to the heat transfer medium at time t; η SF Represents light-to-heat conversion efficiency; S SF Indicates the mirror area of ​​the CSP power station; D solar (t) is the solar radiation per unit area at time t; Q cur (t) is the heat lost at time t.

[0046] 3) Heat storage system model:

[0047] Q TES_ch (t) = η TES_ch (Q H-T (t)+Q HRD (t))(11);

[0048] Q TES_dis (t)=(Q T-H (t)+Q T-HL (t)) / η TES_dis (12);

[0049] Where: Q TES_ch (t) and Q TES_dis (t) represents the heat storage and heat release power of the heat storage system in time period t; η TES_ch and η TES_dis represents the heat storage and heat release efficiency of the heat storage system; Q H-T (t), Q T-H (t) are the thermal power of the heat transfer medium flowing to the heat storage system and the thermal power of the heat storage system flowing to the heat transfer medium at time t; Q HRD (t) is the waste heat recovered from the hydrogen-blended gas turbine at time t; Q T-HL (t) is the thermal energy supplied by the heat storage device to the heat load at time t.

[0050] 4) Power generation system model:

[0051] PCSP (t) = Q H-P (t)η PB (13);

[0052] Where: P CSP (t) represents the power generation of the CSP plant at time t; Q H-P (t) is the thermal power flowing into the power generation system at time t; η PB is the heat-to-electricity conversion efficiency.

[0053] The collaborative operation model of CSP power station and gas-hydrogen mixed heat and power unit includes:

[0054] Both the CSP power station and the gas-hydrogen unit have the ability to independently supply electric and thermal loads, and the two achieve the purpose of coordinated operation through the waste heat recovery device. In order to improve energy utilization, the waste heat recovery device recovers the excess steam heat energy of the gas-hydrogen unit, as shown in the following formula (26); and stores it in the CSP power station heat storage system to participate in the system heat load scheduling, as shown in the following formula (27);

[0055]

[0056] Where: Q' HRD (t) represents the thermal power of the gas-hydrogen blending unit recovered by the device within the period t; η HRD Indicates the operating efficiency of the recovery device; It represents the heating power supplied by the CHP unit to the HRD during period t;

[0057] Q TES_ch (t) = η TES_ch (Q H-T (t)+Q' HRD (t)) (27);

[0058] Where: Q TES_ch (t) represents the heat storage power of the heat storage system in time period t; η TES_ch represents the heat storage efficiency of the heat storage system; Q H-T (t) is the thermal power flowing from HTF to TES at time t.

[0059] In the step 4, an optimization scheduling model of an electric-thermal integrated energy system is established. The system of the present invention mainly includes wind turbines (WT), photovoltaic cells (PV), hydrogen mixed gas turbines (HMGT), P2G (power to gas, P2G) related equipment, concentrating solar power stations (CSP), electric heaters (EH) and electrical energy storage (EES) and other units. The load in the grid consists of electrical load and thermal load; wherein the electrical load is satisfied by wind farms, photovoltaic power generation, hydrogen mixed gas units, power grids and CSP power generation systems, the thermal load is satisfied by hydrogen mixed gas units, electric heaters and CSPs, and the waste heat recovery device (HRD) increases the heat storage capacity of TES by recovering the excess steam heat energy of hydrogen mixed gas turbines.

[0060] The objective function and constraints are as follows:

[0061] a. Objective function:

[0062]

[0063] Where: F represents the total cost of system operation; N T Indicates the scheduling period; C GT (t), C W (t), C EX (t), C ME (t) and They represent the fuel cost, wind and solar power abandonment penalty cost, power interaction cost, equipment operation and maintenance cost, and carbon emission cost of the system in time period t respectively; t represents the scheduling period, t = 1, 2, 3, …, 24.

[0064] ① Fuel cost:

[0065]

[0066] Where: C GT (t) is the fuel cost of the gas turbine in period t; C CH4 is the unit price of natural gas.

[0067] ② Penalty costs for abandoning wind and solar power:

[0068]

[0069] Where: η W Indicates the penalty coefficient for abandoning wind and solar power, They represent the wind power and photovoltaic power input into the system in time period t respectively; P WT,i (t), P PV,i (t) represent the wind power and photovoltaic power absorbed by the system in time period t.

[0070] ③Electricity interaction cost:

[0071]

[0072] Where: P ex (t) represents the interaction power between the power grid and the external power grid in time period t; C rb (t) and C rs (t) are the electricity purchase and sales prices in period t respectively.

[0073] ④ Equipment operation and maintenance costs:

[0074]

[0075] Where: N M is the total number of generating units in the grid; C mi is the unit operation and maintenance cost of unit i; P i (t) is the output of unit i in time period t.

[0076] ⑤Carbon emission cost:

[0077]

[0078] Where: is the unit carbon emission cost coefficient; The CO of the hydrogen-blended gas generator set in time period t 2 Emissions.

[0079] b. Constraints:

[0080] (1) Electrical and thermal power balance constraints:

[0081]

[0082] Q CHP (t)+Q T-HL (t)+Q EH (t) = Q he (t)(21);

[0083] Where: P load (t) is the power load in the grid during time period t.

[0084] (2) Grid interaction power constraints:

[0085]

[0086] Where: xbuy (t) and x sell (t) respectively represent the electricity purchasing and selling status in time period t; P ex，max Indicates the upper limit of the interaction power; P buy (t) represents the amount of electricity purchased by the system from the external power grid during period t, P sell (t) represents the amount of electricity sold by the system to the external power grid during time period t.

[0087] (3) Electric energy storage constraints:

[0088]

[0089] Where: P ES (t) and E ES (t) respectively represent the power and capacity of the electric energy storage in time period t; C ap,ES is the total capacity of electric energy storage; γ ES,D and γ ES,C Respectively represent the maximum charge and discharge rates of electrical energy storage; min and λ max Represents the minimum and maximum state of charge for energy storage; E ES (0) represents the storage capacity of the energy storage at time 0; E ES (N T △t) represents the storage capacity of the electric energy storage at the end of the operation cycle.

[0090] (4) Unit output constraints:

[0091]

[0092] Where: is the power output of unit i in time period t; and are the maximum and minimum output of unit i respectively; and are the up and down ramp rate limits of unit i respectively; Represents the electrical output of unit i during the period (t-1).

[0093] (5) Constraints of the thermal storage system of a CSP plant:

[0094]

[0095] Where: Q TES_ch (t) represents the heat storage power of the heat storage system in time period t; Q TES_dis (t) represents the heat release power of the heat storage system in time period t; are the maximum charging and discharging powers of the heat storage device of the CSP power station at time t; x TES_ch (t), x TES_dis(t) are the charging and releasing states of the heat storage device of the CSP power station at time t; E TES (t) is the capacity of thermal energy storage in time period t.

[0096] In step 5, under the condition of satisfying system constraints, YALMIP programming language and CPLEX solving software are used for simulation analysis. The decision variables of the optimization scheduling model of hydrogen-blended gas units and electric-thermal integrated energy system are the output of each coupled device in each period, the actual output of wind and solar power, purchased electricity power, purchased gas power, etc.

[0097] The present invention provides an optimized operation method of an electric-thermal integrated energy system considering gas-hydrogen blending and a solar thermal power station, and the beneficial effects are as follows:

[0098] (1) In the method of the present invention, the CSP power station cooperates with the gas hydrogen blending technology to participate in energy supply. Compared with the independent operation of traditional gas units, it can effectively improve the system's energy utilization efficiency, renewable energy consumption capacity and scheduling economy, and at the same time reduce carbon emissions.

[0099] (2) After considering the fuel gas hydrogen blending technology, the present invention compared and analyzed with the conventional thermal power coupled CHP unit and found that the optimization model and energy utilization technology route adopted by the present invention have significant advantages in promoting the system's new energy consumption and reducing carbon emissions.

[0100] (3) When the HRD device is considered between the gas-fired unit and the CSP power station, the CSP power station heat storage system can be used more reasonably, significantly improving the IES operation flexibility. The EH can further improve the system efficiency and realize low-carbon economic operation in the grid through "electricity-heat" energy conversion and heating with the IES system. BRIEF DESCRIPTION OF THE DRAWINGS

[0101] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0102] Figure 1 This is a structural diagram of the electric and thermal integrated energy system of the present invention.

[0103] Figure 2 Schematic diagram of the internal energy flow of a solar thermal power station with a combined waste heat recovery device of the present invention.

[0104] Figure 3 This is the electric heat load and wind power photovoltaic prediction output diagram of the present invention.

[0105] Figure 4 This is a diagram of the electric power optimization results of the present invention.

[0106] Figure 5 This is a diagram of the thermal power optimization results of the present invention.

[0107] Figure 6This is a diagram of the power supply situation of a solar thermal power station in different scenarios of the present invention.

[0108] Figure 7 This is a diagram of the heating situation of a solar thermal power station in different scenarios of the present invention.

[0109] Figure 8 This is a diagram of the carbon emissions of the system of the present invention.

[0110] Fig. 9 This is a diagram of the wind and solar power consumption situation of the system of the present invention. DETAILED DESCRIPTION

[0111] In order to effectively promote the consumption of new energy and improve the economic benefits of system operation, the present invention proposes an optimized operation method for an electric and thermal integrated energy system considering gas-hydrogen blending and solar thermal power stations. First, the traditional cogeneration system is transformed into a low-carbon one, and the cogeneration unit is combined with the gas-hydrogen blending technology to construct a mathematical model of the gas-hydrogen blending cogeneration unit. Secondly, a CSP power station with a large-capacity heat storage system is introduced. On this basis, the waste heat recovery device and the electric heater are combined to further solve the peak-valley coordination problem under the guidance of electricity prices, so as to realize the coordinated operation of the gas-hydrogen blending unit and the solar thermal power station. Finally, taking the lowest total system operation cost as the optimization goal, an IES optimization scheduling model for the coordinated energy supply of the gas-hydrogen blending unit and the solar thermal power station is established. By setting 4 different scenarios for comparison, the YALMIP programming language and CPLEX solving software are used for simulation analysis to obtain the optimal output of each device in each period in the system.

[0112] The optimized operation method of the electric-thermal integrated energy system considering gas-hydrogen blending and a solar thermal power station comprises the following steps:

[0113] Step 1: Combine the gas-hydrogen blending technology in the thermal power integrated energy system to build a mathematical model of the gas-hydrogen blending cogeneration unit, as follows:

[0114] 1) Hydrogen-blended gas turbine model:

[0115] Natural gas is mixed with hydrogen in a certain ratio and supplied to the hydrogen mixed gas turbine (HMGT). To ensure the safe and stable operation of the gas turbine, the upper limit of the hydrogen mixing ratio is set to 20%, ignoring the influence of external environmental factors, and its thermoelectric relationship can be expressed as:

[0116]

[0117]

[0118] Where: P GT,g (t) are the natural gas and hydrogen power input to the hydrogen-blended gas turbine during period t; RGT (t) is the hydrogen blending ratio of the gas turbine during period t; are the calorific values ​​of hydrogen and natural gas respectively; P GT,e (t), P GT,h (t) are the electrical and thermal power output of the hydrogen-blended gas turbine during the period t; η GT,e , η GT,h They are the electrical and thermal conversion efficiencies of the hydrogen-blended gas turbine, respectively.

[0119] 2) Electrolyzer model:

[0120] The electrolyzer is an important device for producing hydrogen by electrolyzing water. It can convert randomly fluctuating wind power into hydrogen energy for system use. This paper adopts the proton exchange electrolysis hydrogen production technology, and its model is:

[0121]

[0122] Where: is the hydrogen production power of the electrolyzer in time period t; is the hydrogen production of the electrolyzer in time period t; is the molar mass of hydrogen; is the density of hydrogen.

[0123] 3) Carbon capture equipment:

[0124] The power generation power P of the CHP unit in period t GT,e (t) Most of it is used to supply the electrical load, and the rest of the electrical power P CCS,e (t) Supply to carbon capture equipment. The energy consumption of carbon capture equipment can be divided into two parts: its own fixed electrical power loss P CCS,e1 (t) and operation treatment CO 2 Power consumed P CCS,e2 (t); CO captured by carbon capture equipment 2 The total amount is Part of it is used by the power-to-gas device, and the rest is sealed. The mathematical model is:

[0125]

[0126]

[0127] Where: P CCS,e (t) is the electrical power supplied to the carbon capture equipment; P CCS,e1 (t), P CCS,e2 (t) are the fixed power loss and the CO 2 The electrical power consumed; CO captured by carbon capture equipment 2 Total amount; is the CO of the CHP unit in period t 2 Emissions; GT is the unit carbon emission intensity; CCS The energy required for carbon capture equipment to capture a unit of CO2; μ CCS for carbon capture efficiency; CO2 for carbon capture and storage 2 quantity; CO2 for power-to-gas plants for carbon capture 2 quantity.

[0128] 4) Methane reactor:

[0129] The methane reactor reacts the input hydrogen with the captured carbon dioxide to generate natural gas, which is then supplied to the gas turbine. The mathematical model is as follows:

[0130]

[0131]

[0132] Where: P MR,g (t) are the hydrogen power input into the methane reactor and the natural gas power output from the methane reactor in time period t; are the amount of hydrogen participating in the methane reaction and the amount of natural gas generated by the methane reactor in time period t, respectively; η MR,g is the conversion efficiency of the methane reactor in time period t; is the molar mass of natural gas; is the density of natural gas.

[0133] Step 2: Through the electric-heat conversion characteristics of the electric heater, under the guidance of the time-of-use electricity price mechanism, the gas-hydrogen blending unit is used to supply energy to the user;

[0134] Electric Heater Model:

[0135] The electric heater provides heat to the IES through electricity-heat conversion, and cooperates with the cogeneration system based on electricity prices to meet the heat load demand while increasing the electricity consumption during the valley period to coordinate the peak-valley difference of the electric heat load. Its output model is:

[0136] Q EH (t) = P EH (t)η ah (8)

[0137] Where: Q EH (t) and P EH (t) are the heating power and power consumption of the electric heater in time period t; η ah It is the electric-heat conversion efficiency of the electric heater.

[0138] Step 3: Considering the operation characteristics of the CSP power station participating in energy supply, and based on the heat energy transmission characteristics of the waste heat recovery device, the waste heat of the gas unit is recovered to the CSP power station heat storage system, and a CSP power station-gas-hydrogen cogeneration unit collaborative operation model is established, as follows:

[0139] (1) Waste heat recovery device model

[0140] The excess heat of the HRD recovery system can enhance the flexibility of CSP power plant operation, reduce the operating constraints of thermal power units, and improve the utilization rate of solar energy. Its mathematical model is as follows:

[0141]

[0142] Where: P HRD (t) represents the heat power of the device recovery system in time period t; η HRD Indicates the operating efficiency of the recovery device;

[0143] P HRD , max represents the maximum thermal power of the device recovery system.

[0144] (2) CSP power station model

[0145] A solar thermal power station consists of three parts: a concentrating and collecting system, a heat storage system, and a power generation system. The flow and conversion of energy between the various parts is achieved through heat transfer fluid.

[0146] 1) Concentrating solar collector system

[0147] CSP power stations achieve “light-heat” energy conversion through thermal collectors, which can be expressed as:

[0148] Q S-H (t) = η SF S SF D solar (t)-Q cur (t)(10)

[0149] Where: Q S-H (t) is the thermal power transmitted from the mirror field to the HTF at time t; η SF Represents light-to-heat conversion efficiency; S SF Indicates the mirror area of ​​the CSP power station; D solar (t) is the solar radiation per unit area at time t; Q cur (t) is the heat lost at time t.

[0150] 2) Heat storage system

[0151] The heat storage system can store the residual heat of the heat transfer fluid and the waste heat of the hydrogen-blended gas turbine, and flexibly provide heat or electricity to users. The power relationship between charging and releasing heat can be expressed as:

[0152] Q TES_ch (t) = η TES_ch (Q H-T (t)+Q HRD (t))(11)

[0153] Q TES_dis (t)=(Q T-H (t)+Q T-HL (t)) / η TES_dis (12)

[0154] Where: Q TES_ch (t) and Q TES_dis (t) represents the heat storage and heat release power of the heat storage system in time period t; η TES_ch and η TES_dis represents the heat storage and heat release efficiency of the heat storage system; Q H-T (t)Q T-H (t) are the heat power from HTF to TES and the heat power from TES to HTF at time t; Q HRD (t) is the waste heat recovered from the hydrogen-blended gas turbine at time t; Q T-HL (t) is the thermal energy supplied by the heat storage device to the heat load at time t.

[0155] 3) Power generation system

[0156] The power generation system converts the heat energy transferred by the heat transfer fluid into electrical energy to supply power to the system. The power conversion relationship between electricity and heat can be expressed as:

[0157] P CSP (t) = Q H-P (t)η PB (13)

[0158] Where: P CSP (t) represents the power generation of the CSP plant at time t; Q H-P (t) is the thermal power flowing into the power generation system at time t; η PB is the heat-to-electricity conversion efficiency.

[0159] Step 4: Taking the lowest total system operation cost as the optimization goal, set 4 different comparison scenarios and establish an integrated energy system optimization scheduling model. The objective function and constraints are as follows:

[0160] a. Objective function:

[0161]

[0162] Where: F represents the total cost of system operation; N T Indicates the scheduling period; C GT (t), C W (t), C EX (t), C ME (t) and They respectively represent the fuel cost, wind and solar power abandonment penalty cost, electricity interaction cost, equipment operation and maintenance cost, and carbon emission cost of the system in time period t.

[0163] (1) Fuel costs

[0164]

[0165] Where: C GT (t) is the fuel cost of the gas turbine in period t; C CH4 is the unit price of natural gas.

[0166] (2) Penalty costs for curtailing wind and solar power

[0167]

[0168] Where: η W Indicates the penalty coefficient for abandoning wind and solar power, They represent the wind power and photovoltaic power input into the system in time period t respectively; P WT,i (t), P PV,i (t) represent the wind power and photovoltaic power absorbed by the system in time period t.

[0169] (3) Electricity interaction cost

[0170]

[0171] Where: P ex (t) represents the interaction power between the power grid and the external power grid in time period t; C rb (t) and C rs (t) are the electricity purchase and sales prices in period t respectively.

[0172] (4) Equipment operation and maintenance costs

[0173]

[0174] Where: N M is the total number of generating units in the grid; C mi is the unit operation and maintenance cost of unit i; P i (t) is the output of unit i in time period t.

[0175] (5) Carbon emission costs

[0176]

[0177] Where: is the unit carbon emission cost coefficient.

[0178] b. Constraints:

[0179] (1) Electrical and thermal power balance constraints

[0180]

[0181] Q CHP (t)+Q T-HL (t)+Q EH (t) = Q he (t)(21)

[0182] Where P load (t) is the power load in the grid during time period t.

[0183] (2) Grid interaction power constraints

[0184]

[0185] Where: x buy (t) and x sell (t) respectively represent the electricity purchase and sales status in time period t, P ex，max Indicates the upper limit of the interaction power.

[0186] (3) Electric energy storage constraints

[0187]

[0188] Where: P ES (t) and E ES (t) respectively represent the power and capacity of the electric energy storage in time period t; C ap,ES is the total capacity of electric energy storage; γ ES,D and γ ES,C Respectively represent the maximum charge and discharge rates of electrical energy storage; min and λ max Represents the minimum and maximum state of charge for electrical energy storage.

[0189] (4) Unit output constraints

[0190]

[0191] Where: is the power output of unit i in time period t; and are the maximum and minimum output of unit i respectively; and are the up and down ramp rate limits of unit i respectively.

[0192] (5) Constraints of thermal energy storage systems in CSP plants

[0193]

[0194] Where: are the maximum charging and discharging powers of the heat storage device of the CSP power station at time t; x TES_ch (t), x TES_dis (t) are the charging and releasing states of the heat storage device of the CSP power station at time t; E TES (t) is the capacity of thermal energy storage in time period t.

[0195] Step 5: Under the condition of meeting the system constraints, the YALMIP programming language and CPLEX solving software are used for simulation analysis. Among them, the decision variables of the optimization scheduling model of the combined heat and power system of hydrogen-blended gas units and solar thermal power stations are the output of each coupled device in each period, the actual output of wind and solar, the purchased electricity power, the purchased gas power, etc.

[0196] The IES structure of the present invention is as follows Figure 1 The internal energy flow of the CSP power station with waste heat recovery device is shown in Figure 2 .

[0197] In order to verify the superiority of gas-hydrogen blending technology and CSP power stations in improving wind and solar power consumption rates and reducing carbon emissions in integrated energy systems, the following four typical scenarios are given for comparative analysis:

[0198] Scenario 1: CHP unit operates independently.

[0199] Scenario 2: CHP units and CSP power plants operate in coordination.

[0200] Scenario 3: CSP-CHP-HCNG collaborative operation, excluding EH and HRD.

[0201] Scenario 4: CSP-CHP-HCNG collaborative operation with EH and HRD.

[0202] The scheduling results corresponding to the above four scenarios are shown in Table 2.

[0203] Table 2 Comparison of scheduling results in different scenarios

[0204]

[0205] From the data in Table 2, we can see that the carbon emission cost of the system in scenario 1 is the highest, because the traditional CHP unit does not have any low-carbon measures. At the same time, because the CHP unit is in the "heat-based electricity" operation mode, in order to meet the system's thermal load demand, its power output will be increased accordingly, which compresses the online space of wind and solar power, and the cost of abandoning wind and solar power is also the highest. In addition, without considering the CSP power station, the system purchases a large amount of electricity and natural gas from outside to meet the electricity and thermal load demand.

[0206] Due to the introduction of CSP power station, the equipment operation and maintenance cost of scenario 2 increased by 125,300 yuan compared with scenario 1, but its total cost decreased by 337,700 yuan. Among them, the electricity interaction cost decreased by 53,100 yuan. This is because the CSP power station fully utilized its thermal-electric conversion function to provide electricity to the system during the peak period of electricity load demand, reducing the system's dependence on the external power grid. In addition, because the CSP power station effectively shared the electric and thermal output of the thermal power unit, it reduced the total CO2 emissions of the system and reduced the carbon emission cost by 192,500 yuan; although the participation of the CSP power station in energy supply alleviated the problem of high power output of the CHP unit due to electric-thermal coupling, and the access to wind and solar power was improved, the system still faced the problem of wind and solar power abandonment due to the constraint of the minimum output of the CHP unit.

[0207] Compared with Scenario 2, Scenario 3 reduces the total operating cost by 263,200 yuan, the penalty cost for wind / solar abandonment by 133,400 yuan, and the carbon emission cost by 225,400 yuan. This is because the gas-hydrogen blending technology is taken into account. After the abandoned wind and solar power are converted into hydrogen through hydrogen production, it is mixed with natural gas, and the hydrogen-blended gas unit is used to balance the electric and thermal loads and the fixed energy consumption of the carbon capture device, which helps to further promote the recycling of hydrogen energy and promote the consumption of wind and solar power. Hydrogen production uses abandoned wind and solar power to produce hydrogen, which can reduce the purchase of electricity and save system costs.

[0208] Scenario 4 considers both CSP power plants and gas-hydrogen blending technology, and after the introduction of EH and HRD, the total operating cost is reduced by 212,600 yuan compared with Scenario 3, and the carbon emission cost is reduced by 115,500 yuan, and wind and solar power are basically fully absorbed; among them, HRD recovers waste heat, which not only broadens the heat storage source of TES and enhances the energy supply stability and operation flexibility of CSP power plants, but also TES can realize energy transfer across time periods, further decouple energy production and consumption in time, coordinate the imbalance of "source-load" in the grid, alleviate thermal power operation restrictions, and ensure the regulation capacity of the system. EH plays the role of electricity-heat conversion in IES. Under the time-of-use electricity price mechanism, it cooperates with the system energy supply equipment to meet the heat load, while increasing the power consumption at night and adjusting the peak-to-valley difference of electric and thermal loads. Therefore, the system can reduce the total operating cost and CO2 emissions to varying degrees while also increasing the wind and solar grid access rate.

[0209] In summary, scenario 4 achieves low-carbon energy supply within the system, while having relatively low fuel costs and dependence on external electricity purchases. It is more economical than the above three options, and has the potential to further reduce carbon emissions and increase the access of wind and solar power to the grid.

[0210] The electricity and heat balance of the electricity-heat integrated energy system in scenario 4 is as follows: Figure 4 , Figure 5 shown.

[0211] Power optimization Figure 4 As shown in the figure, after considering the gas hydrogen blending technology, CSP power station, HRD and EH, the system can fully meet various electricity demands under the time-of-use electricity price mechanism. In the period of 01:00-06:00, the CHP unit and CSP power station operate at the minimum power output. At this time, the electricity price is relatively low. The system meets the electricity demand through wind power output and large-scale purchase of electricity from the power grid. In the period of 07:00-8:00, photovoltaic power generation begins, CSP power station and gas units increase power supply and discharge electric energy storage, but the power provided is still insufficient, and it is still necessary to purchase electricity from the external power grid. During the peak period of electricity load, the electricity price reaches the highest, and the system does not need to purchase electricity from the outside. Among them, the wind and solar output is high in the period of 9:00-12:00, and the photovoltaic power generation gradually decreases in the period of 16:00-20:00, but the gas unit and CSP power station have sufficient output and electric energy storage regulation, which can meet the load requirements. Other power-consuming equipment including EH and P2G related devices do not consume additional energy. During the period of 13:00-15:00, in order to ensure the consumption of wind and solar power, the electric energy storage uses its time-shifting characteristics to store excess electric energy, coordinate the peak and valley of the electric load, and ensure the economy of the system. During the period of 21:00-24:00, the electricity price is low, and in the case of wind power, CSP power stations and gas units output, only part of the electricity needs to be purchased from the grid to meet the power demand of the system.

[0212] Thermal optimization Figure 5As shown in the figure, during the periods of 01:00-06:00 and 21:00-24:00, the heat load is relatively high, and the CSP power plant and gas-fired units operate at a large output. At the same time, since the electricity price is at a low point during this period, the system purchases electricity from outside, and the EH shares the heating pressure for the system through electricity-heat conversion. During the period of 07:00-9:00, as the electricity price and electricity load increase, the EH output gradually decreases. During this period, the system is mainly supplied with heat by the CSP power plant and gas-fired units. During the period of 10:00-18:00, due to the high price of purchased electricity, the EH stops working. At the same time, because the light intensity is at a peak stage, the CSP power plant stores heat through light-heat conversion, and the hydrogen-blended gas-fired units provide centralized heating, and the waste heat is recovered through HRD, giving full play to the capacity of TES. By reducing the operating restrictions of the gas turbine units affected by "thermal power generation", the conversion efficiency of the "heat-electricity" cycle inside the CSP power plant can be improved. During the period from 19:00 to 20:00, the heat load demand increases and the CSP power station's thermal storage system begins to supply heat to the system.

[0213] Therefore, through the dual decoupling of the "heat-to-electricity" restriction, the CSP-CHP-HCNG collaborative operation mode in scenario 4 has significantly improved the dispatch flexibility of the integrated energy system. During the dispatch process, energy supply can be reasonably allocated to achieve coordinated operation of electricity and heat, effectively increase the wind power and photovoltaic access rate of the system, and reduce the system's CO 2 Total emissions.

[0214] In order to study the impact of different operation modes of CHP units on CSP plants, Figure 6 , Figure 7 A comparative analysis of CSP power stations under three scenarios is given.

[0215] Power supply conditions such as Figure 6 As shown in the figure, during the period of 8:00-11:00 and 18:00-22:00, the electric load reached the peak, and the CSP power station concentrated the power supply, and created conditions for wind power and photovoltaic output at other times with an output equal to or slightly higher than the minimum unit output. Since HCNG technology is used in scenario 3, during high load periods, the hydrogen-blended gas unit increases the power output by increasing the amount of gas purchased, and the CSP power station can meet the electricity demand with appropriate output, so the power supply is lower than that in scenario 2. The power supply in scenario 4 is higher than that in scenario 3 because HRD recovers the surplus heat energy of the hydrogen-blended gas unit and stores it in the CSP power station, which increases the dispatching capacity and flexibility of the CSP power station. When the electricity demand increases, the energy can be used for coordinated power generation without affecting the heating to users.

[0216] Heating conditions Figure 7As shown, from 1:00 to 7:00 and from 20:00 to 24:00, it is the peak period of heat load and wind power generation is sufficient. During these periods, the CSP power station provides centralized heating, which alleviates the nighttime heating pressure of the gas-fired units, eliminates the limitation of the fixed heat-to-electricity ratio, and reduces the amount of wind abandoned in the system. At the same time, in scenarios 2 and 3, since there is no EH device to supplement the heat supply during the peak period of heat load at night, the heat storage device of the CSP power station needs to increase the heat supply at night, which in disguise reduces the power supply of the CSP power station to the system at night. In scenario 3, due to the consideration of gas-hydrogen blending technology, the abandoned wind produces hydrogen through hydrogen production, which is mixed with natural gas and sent to the gas-fired units to supply the heat load, reducing the heat output of the CSP power station. Therefore, the heat supply in scenario 3 is lower than that in scenario 2. The heating situation in Scenario 4 is not only not affected by the gas-hydrogen blending unit, but the heating supply is improved. This is because the addition of HRD makes full use of the heat storage capacity of the CSP power station, recovers the excess steam waste heat of the CHP unit at noon to store heat in the heat storage system, and releases heat energy in the remaining period to cooperate with the hydrogen-blended gas unit to meet the heat load demand.

[0217] In order to analyze the carbon emissions of the system under each scenario, the system CO 2 Emissions and curves such as Figure 8 As shown. Figure 8 It can be observed that the carbon emissions of the system mainly come from the CHP unit. Through comparative analysis under four different scenarios, it can be seen that the proposed model can effectively reduce the total carbon emissions of the system.

[0218] Scenario 1 and Scenario 2 do not use HCNG technology, resulting in higher total carbon emissions; however, when the CSP power plant participates in energy supply to reduce the output of other equipment, the overall carbon emissions of Scenario 2 are less than those of Scenario 1. Scenario 3 and Scenario 4 both use HCNG technology, so that most of the CO2 emitted by CHP can be captured by CCS, thereby reducing overall carbon emissions. In Scenario 3, the carbon emissions of the CHP unit increased significantly compared to Scenario 2 and Scenario 4. This is because in order to ensure the low carbon nature of the system, the gas-hydrogen blended unit needs to consume electricity at night for hydrogen production in the electrolyzer and CO2 treatment in the carbon capture equipment, which leads to an increase in the power output of the CHP unit at night and the corresponding carbon emissions. Scenario 4 makes full use of HRD. During the day, the surplus heat energy of the CHP unit is recovered and stored in TES, which increases the power output of the CHP unit. At the same time, at night, the CSP power station increases the power generation to share the power consumption of P2G related equipment in the gas-hydrogen blending unit, which not only reduces the power purchase of the system at night, but also retains the heating capacity of the CSP power station, and improves the energy supply reliability and energy utilization efficiency of the system. Therefore, the total carbon emissions of scenario 4 are the lowest.

[0219] In order to understand the effectiveness of the system in wind and solar grid access, Fig. 9A comparison of wind and solar power consumption in different scenarios is given.

[0220] according to Fig. 9 According to the data, the phenomenon of wind and solar power abandonment mainly occurs in the time periods of 1:00-5:00, 10:00-18:00 and 22:00-24:00. Among them, in the time periods of 1:00-5:00 and 22:00-24:00, the thermal load is high and the electrical load is low. In the operation mode of fixed thermal power ratio, the CHP unit has a high power output. However, this is the time when wind power is generated most, and the space for wind power to be connected to the grid is greatly compressed, resulting in the waste of wind power. At 10:00-11:00, the system power load reaches its peak. At this time, the photovoltaic output increases and the wind power output decreases, but the larger power output of thermal power units and CSP power stations compresses the photovoltaic power generation space, resulting in abandoned light; from 12:00 to 18:00, photovoltaic power is at its peak. The CSP power station stores thermal energy to TES through the concentrating solar collector system and HRD device, and also provides thermal energy for power generation to the system. Although the CSP power station operates at the minimum output to make way for photovoltaic power generation, the thermal power output of the gas unit has reached the highest level in the scheduling cycle at this time, and the power output is forced to increase, resulting in a large amount of wind energy and light energy being wasted.

[0221] from Fig. 9 China Energy observed that the wind and solar consumption in Scenario 2 is higher than that in Scenario 1, because the addition of the CSP power station enriches the source of nighttime heating, and the "heat-based electricity" constraint of the CHP unit reduces its power output, freeing up space for wind power to be connected to the grid. At the same time, during the day, the CSP power station smoothes the volatility of photovoltaic power generation and reduces the abandonment of light. The wind and solar grid-connected rate in Scenario 3 is higher than that in Scenario 2, because in Scenario 3, after considering the hydrogenation of gas, the abandoned wind and solar power are preferentially used in the power-to-hydrogen device to produce hydrogen and the carbon capture equipment to treat CO2, which promotes the wind and solar consumption. After the introduction of HRD and EH in Scenario 4, HRD recovers the surplus heat energy in the thermal power unit during the day and stores it in TES, which improves the operational flexibility of the system, and EH consumes wind power through electric-heat conversion during the period of large wind power generation at night, relieving the heating pressure for the system. Therefore, the wind and solar utilization rate in Scenario 4 is the highest.

Claims

1. An optimized operation method of an electric-thermal integrated energy system considering gas-hydrogen blending and a solar thermal power station, characterized in that The following steps are involved: Step 1: Combine gas-hydrogen blending technology in the thermal power integrated energy system to build a gas-hydrogen blending cogeneration unit model; Step 2: Through the electric-heat conversion characteristics of the electric heater, under the guidance of the time-of-use electricity price mechanism, the gas-hydrogen-blended cogeneration unit is used to supply energy to users; Step 3: Considering the operation characteristics of the CSP power station participating in energy supply, and based on the heat energy transmission characteristics of the waste heat recovery device, the waste heat of the gas unit is recovered to the CSP power station heat storage system, and a collaborative operation model of the CSP power station-gas-hydrogen-blended cogeneration unit is established; Step 4: Taking the lowest total system operation cost as the optimization goal, set different comparison scenarios and establish an optimization scheduling model for the electric and thermal integrated energy system; Step 5: Perform simulation analysis under the condition of satisfying the constraints of the electric-thermal integrated energy system to obtain the optimal output of each device in each time period in the electric-thermal integrated energy system.

2. The method for optimizing the operation of an electric-thermal integrated energy system considering gas-hydrogen blending and a solar thermal power station according to claim 1, characterized in that: In step 1, the model of the gas-hydrogen mixed heat and power cogeneration unit is established as follows: 1) Hydrogen-blended gas turbine model: Where: P GT,g (t) are the natural gas and hydrogen power input to the hydrogen-blended gas turbine during period t; R GT (t) is the hydrogen blending ratio of the gas turbine during period t; are the calorific values ​​of hydrogen and natural gas respectively; P GT,e (t), P GT,h (t) are the electrical and thermal power output of the hydrogen-blended gas turbine during the period t; η GT,e , η GT,h They are the electricity and heat conversion efficiency of hydrogen-doped gas turbines respectively; 2) Electrolyzer model: Where: is the hydrogen production power of the electrolyzer in time period t; is the hydrogen production of the electrolyzer in time period t; is the molar mass of hydrogen; is the hydrogen density; △t represents the scheduling period; 3) Carbon capture equipment model: Where: P CCS,e (t) is the electrical power supplied to the carbon capture equipment; P GT,e represents the electric power output of the gas turbine during the period t; P CCS,e1 (t), P CCS,e2 (t) are the fixed power loss and the power consumed by the CO2 treatment operation; The total amount of CO2 captured by the carbon capture equipment; is the CO2 emission of the CHP unit in period t; e GT is the unit carbon emission intensity; CCS The energy required for carbon capture equipment to capture a unit of CO2; μ CCS for carbon capture efficiency; The amount of CO2 stored for carbon capture; The amount of CO2 supplied to the power-to-gas plant for carbon capture; 4) Methane reactor model: Where: P MR,g (t) are the hydrogen power input into the methane reactor and the natural gas power output from the methane reactor in time period t; are the amount of hydrogen participating in the methane reaction and the amount of natural gas generated by the methane reactor in time period t, respectively; η MR,g is the conversion efficiency of the methane reactor in time period t; is the molar mass of natural gas; is the density of natural gas.

3. The method for optimizing the operation of an electric-thermal integrated energy system considering gas-hydrogen blending and a solar thermal power station according to claim 1, characterized in that: In step 2, an electric heater model is established: Q EH (t)=P EH (t)η ah (8); Where: Q EH (t) and P EH (t) are the heating power and power consumption of the electric heater in time period t; η ah It is the electric-heat conversion efficiency of the electric heater.

4. The method for optimizing the operation of an electric-thermal integrated energy system considering gas-hydrogen blending and a solar thermal power station according to claim 1, characterized in that: In step 3, a CSP power plant model that operates in coordination with a gas-hydrogen-blended cogeneration unit is established, including: 1) The model of waste heat recovery device is: Where: P HRD (t) represents the heat power of the device recovery system in time period t; η HRD Indicates the operating efficiency of the recovery device; P HRD，max Indicates the maximum heat power of the device recovery system; It represents the heating power supplied by the CHP unit to the HRD during period t; 2) Concentrating solar collector system model: Q S-H (t)=η SF S SF D solar (t)-Q cur (t)(10); Where: Q S-H (t) is the heat power transmitted from the mirror field to the heat transfer medium at time t; η SF Represents light-to-heat conversion efficiency; S SF Indicates the mirror area of ​​the CSP power station; D solar (t) is the solar radiation per unit area at time t; Q cur (t) is the heat loss at time t; 3) Heat storage system model: Q TES_ch (t)=η TES_ch (Q H-T (t)+Q HRD (t))(11); Q TES_dis (t)=(Q T-H (t)+Q T-HL (t)) / η TES_dis (12); Where: Q TES_ch (t) and Q TES_dis (t) represents the heat storage and heat release power of the heat storage system in time period t; η TES_ch and η TES_dis represents the heat storage and heat release efficiency of the heat storage system; Q H-T (t), Q T-H (t) are the thermal power of the heat transfer medium flowing to the heat storage system and the thermal power of the heat storage system flowing to the heat transfer medium at time t; Q HRD (t) is the waste heat recovered from the hydrogen-blended gas turbine at time t; Q T-HL (t) is the heat energy supplied by the heat storage device to the heat load at time t; 4) Power generation system model: P CSP (t)=Q H-P (t)η PB (13); Where: P CSP (t) represents the power generation of the CSP plant at time t; Q H-P (t) is the thermal power flowing into the power generation system at time t; η PB is the heat-to-electricity conversion efficiency.

5. The method for optimizing the operation of an electric-thermal integrated energy system considering gas-hydrogen blending and a solar thermal power station according to claim 4, characterized in that: The collaborative operation model of CSP power station and gas-hydrogen mixed heat and power unit includes: Both the CSP power station and the gas-hydrogen blending unit have the ability to independently supply electric and thermal loads, and the two achieve the purpose of coordinated operation through the waste heat recovery device; the waste heat recovery device recovers the excess steam heat energy of the gas-hydrogen blending unit, as shown in the following formula (26); and stores it in the CSP power station heat storage system, participating in the system heat load scheduling, as shown in the following formula (27); Where: Q' HRD (t) represents the thermal power of the gas-hydrogen blending unit recovered by the device within the period t; η HRD Indicates the operating efficiency of the recovery device; It represents the heating power supplied by the CHP unit to the HRD during period t; Q TES_ch (t)=η TES_ch (Q H-T (t)+Q' HRD (t)) (27); Where: Q TES_ch (t) represents the heat storage power of the heat storage system in time period t; η TES_ch represents the heat storage efficiency of the heat storage system; Q H-T (t) is the thermal power flowing from HTF to TES at time t.

6. The method for optimizing the operation of an electric-thermal integrated energy system considering gas-hydrogen blending and a solar thermal power station according to claim 1, characterized in that: In the step 4, an optimization scheduling model of an electric-thermal integrated energy system is established, including a wind turbine (WT), a photovoltaic cell (PV), a hydrogen mixed gas turbine (HMGT), P2G (power to gas, P2G) related equipment, a concentrating solar power station (CSP), an electric heater (EH) and an electrical energy storage (EES) unit; the load in the grid is composed of an electric load and a thermal load; a heat recovery device (HRD) increases the heat storage capacity of TES by recovering the excess steam heat energy of the hydrogen mixed gas turbine; The objective function and constraints are as follows: a. Objective function: Where: F represents the total cost of system operation; N T Indicates the scheduling period; C GT (t), C W (t), C EX (t), C ME (t) and They represent the fuel cost, wind and solar power abandonment penalty cost, power interaction cost, equipment operation and maintenance cost, and carbon emission cost of the system in time period t respectively; t represents the scheduling period, t = 1, 2, 3, …, 24; ① Fuel cost: Where: C GT (t) is the fuel cost of the gas turbine in period t; C CH4 is the unit price of natural gas; ② Penalty costs for abandoning wind and solar power: Where: η W represents the penalty coefficient for abandoning wind and solar power, They represent the wind power and photovoltaic power input into the system in time period t respectively; P WT,i (t), P PV,i (t) represent the wind power and photovoltaic power absorbed by the system in time period t respectively; ③Electricity interaction cost: Where: P ex (t) represents the interaction power between the power grid and the external power grid in time period t; C rb (t) and C rs (t) are the electricity purchase and sales prices for time period t; ④ Equipment operation and maintenance costs: Where: N M is the total number of generating units in the grid; C mi is the unit operation and maintenance cost of unit i; P i (t) is the output of unit i in period t; ⑤Carbon emission cost: Where: is the unit carbon emission cost coefficient; Indicates the CO2 emissions of the hydrogen-blended gas generator set within time period t; b. Constraints: (1) Electrical and thermal power balance constraints: Q CHP (t)+Q T-HL (t)+Q EH (t)=Q he (t)(21); Where: P load (t) is the power load in the grid during time period t; (2) Grid interaction power constraints: Where: x buy (t) and x sell (t) respectively represent the electricity purchasing and selling status in time period t; P ex，max Indicates the upper limit of the interaction power; P buy (t) represents the amount of electricity purchased by the system from the external power grid during period t, P sell (t) represents the amount of electricity sold by the system to the external power grid during time period t; (3) Electric energy storage constraints: Where: P ES (t) and E ES (t) represent the power and capacity of the electric energy storage in time period t respectively; C ap,ES is the total capacity of electrical energy storage; γ ES,D and γ ES,C Respectively represent the maximum charge and discharge rates of electrical energy storage; min and λ max Represents the minimum and maximum state of charge for energy storage; E ES (0) represents the storage capacity of the energy storage at time 0; E ES (N T △t) represents the storage capacity of the electric energy storage at the end of the operation cycle; (4) Unit output constraints: Where: P i CG (t) is the power output of unit i in time period t; and are the maximum and minimum output of unit i respectively; and are the up and down ramp rate limits of unit i respectively; P i CG (t-1) represents the power output of unit i in the period (t-1); (5) Constraints of the thermal storage system of a CSP plant: Where: Q TES_ch (t) represents the heat storage power of the heat storage system in time period t; Q TES_dis (t) represents the heat release power of the heat storage system in time period t; are the maximum charging and discharging powers of the heat storage device of the CSP power station at time t; x TES_ch (t), x TES_dis (t) are the charging and releasing states of the heat storage device of the CSP power station at time t; E TES (t) is the capacity of thermal energy storage in time period t.

7. The method for optimizing the operation of an electric-thermal integrated energy system considering gas-hydrogen blending and a solar thermal power station according to claim 1, characterized in that: In step 5, under the condition of satisfying system constraints, YALMIP programming language and CPLEX solving software are used for simulation analysis; the decision variables of the optimization scheduling model of the hydrogen-blended gas-fired unit and the electric and thermal integrated energy system are the output of each coupled device in each time period, the actual output of wind and solar power, the purchased electricity power, and the purchased gas power.

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