Comprehensive energy system optimization scheduling method based on combined hydrogen production and demand response strategy

Abstract

The invention discloses a comprehensive energy system optimal scheduling method based on a combined hydrogen production and demand response strategy. The comprehensive energy system optimal scheduling method comprises the steps that a hydrogen-containing comprehensive energy system model comprising an electrolytic bath, gas hydrogen production equipment, an electric boiler, a hydrogen storage tank, a hydrogen fuel cell and a heat storage device is built; constructing a flexible load model, and setting a satisfaction degree evaluation index; constructing an output constraint and a power balance constraint of each device in the hydrogen-containing comprehensive energy system model; and establishing an optimal scheduling model of the hydrogen-containing comprehensive energy system, and taking the minimum total cost as an optimization target. According to the method, the load curve of the load side is optimized by establishing the multi-element hydrogen production dynamic model and the flexible load model, and the hydrogen supply flexibility is improved; and meanwhile, the model proposed by the method effectively reduces the carbon emission, the wind curtailment rate and the total cost of the system.

Description

Technical Field

[0001] The present invention relates to the field of integrated energy system optimization and scheduling, and in particular to an integrated energy system optimization and scheduling method based on a combined hydrogen production and demand response strategy. Background Art

[0002] With existing technologies, renewable energy installations are experiencing explosive growth. However, this rapid expansion has also exposed shortcomings in system regulation capabilities, such as high average wind curtailment rates. This highlights the importance of resolving the contradiction between the uneven spatial and temporal distribution of wind and solar resources and the need for flexible power system regulation. Against this backdrop, hydrogen, as a secondary energy carrier with both zero-carbon properties and energy hub capabilities, is reshaping the evolution of the Integrated Energy System (IES). Through conversion devices such as water electrolysis, fuel cells, and gas turbines, hydrogen can deeply couple multiple energy forms—electricity, heat, and chemical energy—to form a new energy network that coordinates multiple energy flows: electricity, hydrogen, heat, and gas. Facing the system regulation challenges presented by the large-scale integration of renewable energy, building a coordinated and optimized dispatching system that integrates multiple technology approaches, such as hydrogen production from water electrolysis (P2G) and hydrogen production from natural gas reforming (SMR), holds significant practical significance.

[0003] As a key flexible resource, water electrolysis hydrogen production can not only smooth out fluctuations in renewable energy output but also generate economic benefits through participation in electricity spot markets and ancillary services markets. Natural gas hydrogen production, leveraging a mature industrial chain, can also become a low-carbon baseload hydrogen source with the addition of a carbon capture and sequestration system (CCUS). Flexible loads can effectively achieve a dynamic balance between electricity supply and demand, optimizing the system's load curve and achieving peak-shaving and valley-filling effects, further improving the system's capacity to absorb new energy and reducing its carbon emissions.

[0004] In the optimization and scheduling of existing hydrogen-containing integrated energy systems, single hydrogen production from water electrolysis, coal, or natural gas is often considered on the source side. However, different hydrogen production modes have their own advantages, and a single hydrogen production mode is difficult to fully utilize their respective characteristics. The combined hydrogen production model requires the collaboration of multiple hydrogen production methods. By optimizing the hydrogen-containing integrated energy system by combining their respective economic, efficiency, and environmental advantages, it can optimize the energy distribution in the system and reduce the system's economic costs and carbon emissions. In the integrated energy system, there is relatively more research on the load side, but less on its optimization in combination with combined hydrogen production. It is also crucial to study the impact of flexible loads on combined hydrogen production in the hydrogen-containing integrated energy system, which is of great significance to providing comprehensive energy efficiency. Summary of the Invention

[0005] The present invention provides an optimized scheduling method for an integrated energy system based on a combined hydrogen production and demand response strategy. Compared with traditional integrated energy systems, this method optimizes the load curve on the load side and improves the flexibility of hydrogen supply by establishing a multi-element hydrogen production dynamic model and a flexible load model. At the same time, the model proposed by this method effectively reduces the system's carbon emissions, wind curtailment rate and total cost.

[0006] The technical solution adopted by the present invention is: The integrated energy system optimization scheduling method based on the combined hydrogen production and demand response strategy includes the following steps: Step 1: Build a hydrogen-containing integrated energy system model that includes an electrolyzer, gas-to-hydrogen equipment, an electric boiler, a hydrogen storage tank, a hydrogen fuel cell, and a heat storage device; Step 2: Construct a flexible load model and set satisfaction evaluation indicators; Step 3: Construct the output constraints and power balance constraints of each device in the hydrogen-containing integrated energy system model; Step 4: Establish an optimal scheduling model for the hydrogen-containing integrated energy system, with the minimum total cost as the optimization goal.

[0007] In step 1, first, a model block diagram of the hydrogen-containing integrated energy system of the present invention is constructed, such as Figure 1 As shown. Figure 1 It can be seen that the hydrogen-containing integrated energy system mainly supplies energy through the energy supply side including the upper power grid, wind power, and natural gas grid; then, through the electric-thermal-hydrogen energy conversion, different types of energy are effectively coupled to supply energy to the load. Among them, the energy conversion module mainly includes hydrogen production, storage, and utilization modules, as well as electric boilers (Electric Boiler, EB) and their heat storage devices (Heat Storage Module, HSM). The main equipment involved are: electrolyzer (Electrolyzer, EL), gas to hydrogen equipment (Gas to Hydrogen, G2H), hydrogen storage tanks (B Hydrogen Storage, BHS, GHS), hydrogen fuel cells (HFC), and carbon capture (Carbon Capture, CC); In this hydrogen-containing integrated energy system model, hydrogen energy is subdivided into blue and green hydrogen, which are used as energy media to couple electricity, heat, gas, and hydrogen energy, strengthening the connection between hydrogen energy and other energy sources and improving the flexibility of the system. Then, a model is established for each electrical device in the hydrogen-containing integrated energy system: 1) PEM water electrolysis hydrogen production model: (1); In formula (1): fort Water consumption of EL equipment during the period; for t The amount of green hydrogen produced by EL equipment during the period; For EL devices t Electric power consumed during the time period; 、 、 They are the water consumption coefficient of EL equipment, the electricity-to-hydrogen conversion efficiency coefficient, and the lower calorific value of hydrogen; 、 They are the upper and lower limits of the power consumption of EL equipment respectively; The scheduling duration for the unit.

[0008] 2) Natural gas hydrogen production model: The more mature natural gas steam reforming (pressure swing advertising, PSA) hydrogen production is adopted. The specific model is as follows: (2); In formula (2): for t The amount of blue hydrogen produced by G2H equipment during this period, for t The amount of natural gas consumed by the G2H equipment during the period; The efficiency of gas-to-hydrogen conversion of G2H equipment; is the lower calorific value of natural gas; for t Power consumption of G2H equipment during the time period; for t The amount of water consumed by the G2H equipment during the period; for t Carbon emissions generated by G2H equipment during the period; 、 、 They are the power consumption coefficient, water consumption coefficient, and carbon emission coefficient of the G2H equipment; 、 , respectively t The upper and lower limits of blue hydrogen production during a period; 、 They are t The upper and lower limits of natural gas intake during a period.

[0009] 3) Electric boiler model: (3); In formula (3): for t Heating power of EB equipment during the time period; for t The electric power consumed by the EB equipment during the time period; is the electrical-to-heat coefficient of the EB device; 、 They are the upper and lower limits of the power consumption of the EB equipment respectively.

[0010] 4) Hydrogen storage model: (4); In formula (4): for t The amount of hydrogen in the hydrogen storage tank during the period; for t Change in hydrogen storage during a period of time; 、 They are t The input and output of hydrogen storage tanks during each period; 、 is a binary variable, When it is 1, it indicates intake. When it is 1, it means exhalation; 、 They respectively represent the upper and lower limits of hydrogen storage in the hydrogen storage tank.

[0011] 5) Hydrogen fuel cell model: (5); In formula (5): 、 They are t The power generation and heat generation of HFC during the period; for t Hydrogen consumption during the period; 、 are the hydrogen-to-electricity coefficient and hydrogen-to-heat coefficient of hydrogen respectively; 、 They are the upper and lower limits of hydrogen power generation respectively.

[0012] 6) Heat storage device model: (6); In formula (6): for t Heat storage capacity during the period; 、 They are t The heat injected and transferred out of the time period heat storage device; 、 are binary variables, among which When it is 1, it means heat is injected. When it is 1, it means heat is transferred out; 、 are the upper and lower limits of heat storage of the heat storage device respectively.

[0013] In step 2, in the present invention, the flexible loads are mainly classified into Class I transferable loads, Class II replaceable loads, and Class III fixed loads. When the hydrogen-containing integrated energy system meets the demand for fixed loads, Class I transferable loads and Class II replaceable loads can adjust their own energy consumption levels to optimize the load curve and improve the overall energy consumption level of the system; (7); In formula (7): k Indicates the type of load, , Indicates the electrical load, represents the heat load, for t Time period k The total power of the load; for t Time period k Transferable loads of class loads; for t Time period k Replaceable loads for similar loads; for t Time period k Fixed load of type load.

[0014] 1) Class I electric-thermal transferable load: (8); In formula (8): 、 Respectively k Type of load t The amount of Class I load after transfer and the amount involved in the transfer during the period; Indicates the k Type of load t The quantity before the transfer of Category I load in the time period; 、 They are t The power transfer-in and transfer-out values ​​of Class I loads during the time period; 、 is a binary variable, which is the kth load t The indicator quantity of the first category load transfer in the time period; 、 Respectively represent k Type of load t The upper and lower limits of the transfer power of Category I load in the time period; Indicates the scheduling period; It means that the transfer-in and transfer-out amounts of transferable load are conserved within a scheduling cycle.

[0015] 2) Category II electric-thermal replaceable loads: (9); In formula (9): 、 Respectively t The power values ​​of the electric and thermal replaceable loads after time period substitution; 、 Respectively t The power value of the electric and thermal replaceable loads in the time period; 、 They are t Initial values ​​of the replaceable loads of electricity and heat for the time period; 、 Respectively t The period electricity can replace the load's transfer-in and transfer-out power.

[0016] 、 Respectively t Time period heat can replace the transfer in and out power of the load.

[0017] 、 Are binary variables, representing t The time period electricity can replace the load transfer in and out mark quantity.

[0018] 、 Are binary variables, representing t The time period heat can replace the load transfer in and out mark quantity.

[0019] 、 Respectively t Time-period electricity can replace the load to participate in the regulation of power upper and lower limits.

[0020] 、 Respectively t Time period heat can replace load to participate in the upper and lower limits of power regulation.

[0021] 3) User and electrolyzer equipment satisfaction indicators: Flexible loads can adjust users' energy consumption behavior, not only reducing their energy costs and improving power supply reliability, but also reducing environmental impact. However, this will affect users' energy consumption experience. Therefore, this paper proposes an evaluation index that considers power transfer: (10); (11); (12); (13); In the above formula: 、 、 These are the user satisfaction indicators for electricity consumption, price, and electrolyzer equipment; It represents the amount of Class I load participating in the transfer during the electric load period t; It indicates the amount of Class II load participating in the transfer during the electric load period t; represents the total amount of electric load during period t; for t The electricity purchase price for the time period; Before load change t Electricity consumption during the time period; for t The cost change due to load changes during a period is used to measure the satisfaction relationship between the user side and the energy supply side; represents the power of the electrolytic cell at time t+1; represents the power of the electrolytic cell at time t.

[0022] In step 3, the output constraints and power balance constraints of each device in the hydrogen-containing integrated energy system model are constructed, including the following: 1) Electric power balance constraints: (14); In formula (14): represents the purchased power during period t; represents the wind power consumption during period t; represents the power generation power of the green hydrogen cogeneration unit during period t; represents the power generation power of the blue hydrogen cogeneration unit during period t; for t Electricity load value of the time period; represents the power consumption of producing blue hydrogen during period t; represents the power consumption of the electrolytic cell during period t; It represents the power consumption of the electric boiler during period t; represents the power consumption of the carbon capture equipment during period t.

[0023] 2) Thermal power balance constraints: (15); In formula (15): for t Heat load value of the time period; represents the heat production power of the blue hydrogen cogeneration unit during period t; represents the heat production power of the green hydrogen cogeneration unit during period t; represents the heating power of the electric boiler during period t; Indicates the heat storage power of the heat storage device; Indicates the heat release power of the heat storage device.

[0024] 3) Hydrogen supply and demand balance: (16); In formula (16): 、 are the input and output of the green hydrogen storage tank respectively; 、 are the input and output of the blue hydrogen storage tank respectively; represents the hydrogen production of the electrolyzer during period t; It represents the hydrogen production of the gas-to-hydrogen equipment during period t; represents the hydrogen consumption of the green hydrogen cogeneration unit during period t; represents the hydrogen consumption of the blue hydrogen cogeneration unit during period t; represents the supply of green hydrogen to hydrogen load during period t; It represents the supply of blue hydrogen to hydrogen load during period t.

[0025] 4) Energy storage equipment constraints: It mainly constrains the input and output of energy storage equipment in each period: (17); In formula (17): 、 Represent the initial and final values ​​of the equivalent charge state of different energy storage devices, where ; represents the minimum hydrogen storage rate of blue hydrogen during period t; represents the maximum hydrogen storage rate of blue hydrogen during period t; represents the minimum hydrogen storage rate of green hydrogen during period t; represents the maximum hydrogen storage rate of green hydrogen during period t; 、 They represent the hydrogen storage rates of green hydrogen and blue hydrogen in period t respectively.

[0026] represents the minimum input power of the heat storage device during period t; represents the maximum input power of the heat storage device during period t; Represents the heat storage power of the heat storage device during period t.

[0027] 5) Wind power equipment constraints: To avoid damage to the unit, the output of the wind turbine must not exceed the unit's threshold: (18); In formula (18): 、 They are the upper and lower limits of the fan output respectively.

[0028] 6) Power purchase constraints: The system's purchase of electricity from the upper-level power grid must not exceed a certain threshold: (19); In formula (19): 、 are the upper and lower limits of purchased power respectively; Represents the purchased electricity power during period t.

[0029] In step 4, an optimization scheduling model for a hydrogen-containing integrated energy system is established, including a combined hydrogen production dynamic model and comprehensive consideration of carbon emission costs, wind curtailment costs, wind turbine operating costs, electrolyzer depreciation costs, blue hydrogen purification costs, flexible load compensation costs, and electricity purchase costs. The optimization is targeted at minimizing the total cost, and includes the following steps: 1) Dynamic model of combined hydrogen production: (20); In formula (20): The total hydrogen load supply; 、 The supply of green hydrogen and blue hydrogen respectively; 、 are the proportion coefficients of green hydrogen and blue hydrogen respectively; This is the minimum supply ratio of green hydrogen, which aims to avoid the extreme situation of blue hydrogen being supplied alone and ensure the utilization rate of green hydrogen.

[0030] 2) Carbon emission costs: (twenty one); In formula (21): represents the cost of carbon emissions; represents the carbon emissions from producing blue hydrogen; represents the amount of CO2 collected by carbon capture; Indicates the scheduling period; is the base price of unit carbon emissions; 、 、 All are carbon emission factors of energy purchased at the upper level; for t The amount of electricity purchased from the upper-level power grid during this period.

[0031] 3) Wind curtailment costs and wind turbine operating costs: (twenty two); In formula (22): represents the cost of wind curtailment and the operating cost of wind turbines; 、 are the actual power and maximum power of the wind turbine respectively; is the cost coefficient for wind turbine operation; is the unit wind curtailment cost factor; Indicates the scheduling period.

[0032] 4) Energy purchase cost at the upper level: The system's upper-level energy purchase cost mainly consists of three parts: electricity purchase, gas purchase, and water purchase, which can be expressed as follows: (twenty three); In formula (23): represents the cost of purchased energy; represents the purchased power during period t; represents the blue hydrogen production during period t; represents the water consumption of the electrolytic cell during period t; Indicates the water consumption of hydrogen production from natural gas during period t; 、 、 They are the real-time electricity price, gas price and water price of the system respectively.

[0033] 5) Cost of electrolyzer power fluctuation: (twenty four); In formula (24): represents the depreciation cost of the electrolytic cell; is the loss factor of the electrolytic cell caused by power fluctuation; 、 They represent the power of the electrolytic cell during period t and period t-1 respectively.

[0034] 6) Blue hydrogen purification cost: (25); In formula (25): represents the purification cost of blue hydrogen; is the purification cost coefficient of unit blue hydrogen; Represents the production of blue hydrogen in period t.

[0035] 7) Flexible load compensation cost: (26); In formula (26): represents the compensation cost of flexible load; 、 are the unit compensation factors for transferable loads and replaceable loads, respectively; It represents the power of the kth load and the first type of load participating in the transfer during the t period; It represents the power replaced by the type II load in the kth load period t.

[0036] The present invention provides an integrated energy system optimization scheduling method based on combined hydrogen production and demand response strategy, with the following technical effects: 1) The PEM electrolyzer model constructed in step 1 of the present invention fully considers the relationship between the Faraday effect and voltage efficiency, and establishes a power-efficiency model of the electrolyzer based on the empirical model of temperature and current, which can fully reflect the characteristics of hydrogen production; at the same time, the other power equipment models constructed can reflect the energy characteristics of the integrated energy system, laying the foundation for subsequent analysis.

[0037] 2) The flexible load model constructed in step 2 of the present invention fully considers the transferability and substitutability of the load, enabling it to play its advantages in load regulation; the establishment of electricity satisfaction, price satisfaction, and electrolytic cell equipment satisfaction indicators can fully reflect the impact of load regulation on user energy experience and the impact on electrolytic cell operating conditions.

[0038] 3) The device output constraint and power constraint established in step 3 of the present invention can ensure the normal operation of each device and accurately reflect the actual situation, making it more valuable for application.

[0039] 4) In the hydrogen-containing integrated energy system optimization scheduling model constructed in step 4 of the present invention, the joint supply characteristics of blue hydrogen and green hydrogen are fully considered, so that the sources of hydrogen energy in the system are diversified. At the same time, the dynamic proportion model setting can further improve the flexibility of hydrogen energy supply, thereby giving play to the economic advantages of blue hydrogen and reducing the total cost of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The present invention will be further described below with reference to the accompanying drawings and examples: Figure 1 This is a framework diagram of the integrated energy system based on the combined hydrogen production and demand response strategy of the present invention.

[0041] Figure 2 A graph showing the power-efficiency of the electrolyzer constructed for the present invention.

[0042] Figure 3 This is a comparison chart before and after optimization of the electric heating flexible load in scenario 4 of the present invention.

[0043] Figure 4 This is the flexible load optimization scheduling result of the present invention.

[0044] Figure 5 This is the dynamic ratio diagram of blue and green hydrogen before optimization of the present invention.

[0045] Figure 6 This is the dynamic ratio diagram of blue and green hydrogen after optimization of the present invention.

[0046] Figure 7 This is the evaluation result of the satisfaction index of the present invention.

[0047] Figure 8 This is the electric power balance diagram of the present invention.

[0048] Figure 9 This is the thermal power balance diagram of the present invention.

[0049] Figure 10 This is the hydrogen energy balance diagram of the present invention. DETAILED DESCRIPTION

[0050] The present invention sets up four different scenario simulations to verify the reliability of the model proposed in the present invention based on the integrated energy system optimization scheduling method based on the combined hydrogen production and demand response strategy, including the following steps: First, set up four different scenarios as follows: Scenario 1: Only green hydrogen and blue hydrogen are considered as single hydrogen supply modes.

[0051] Scenario 2: Considering the traditional utilization mode of blue and green hydrogen, the blue and green hydrogen supply in the hydrogen load is a fixed ratio, which is set to 1:1 in this scenario.

[0052] Scenario 3: Considering the flexible utilization mode of blue and green hydrogen, that is, the flexible optimization scheduling scenario with dynamic proportions of blue and green hydrogen.

[0053] Scenario 4: Based on Scenario 3, flexible load is added and the impact of user-side demand response on the optimization results is considered, which is the method proposed in this paper.

[0054] Then, solve the model according to the following steps.

[0055] Step 1: Build a model of the hydrogen-containing integrated energy system, including: PEM electrolyzer, gas-to-hydrogen, electric boiler, hydrogen storage tank, hydrogen fuel cell, and heat storage device; Step 2: Construct a flexible load model and evaluation indicators based on transferability and substitutability; Step 3: Construct output constraints and power balance constraints for each device in the system; Step 4: Establish an optimal scheduling model for a hydrogen-containing integrated energy system, including a dynamic model for hydrogen energy supply and comprehensive consideration of carbon emission costs, wind curtailment costs, wind turbine operating costs, electrolyzer depreciation costs, blue hydrogen purification costs, flexible load compensation costs, and electricity purchase costs, with the goal of minimizing the total cost.

[0056] In step 1, a model of a hydrogen-containing integrated energy system is constructed, including: a PEM electrolyzer, gas-to-hydrogen, an electric boiler, a hydrogen storage tank, a hydrogen fuel cell, and a heat storage device, including the following steps: like Figure 1 The figure shows the framework of the integrated energy system based on the combined hydrogen production and demand response strategy of the present invention. The system primarily supplies energy through the energy supply side, including the upper power grid, wind power, and natural gas grid; then, through electric-thermal-hydrogen energy conversion, different types of energy are effectively coupled to supply energy to the load. The energy conversion module mainly includes hydrogen production, storage, and utilization modules, as well as an electric boiler (EB) and its heat storage module (HSM). The main equipment involved includes: electrolyzer (EL), gas to hydrogen equipment (G2H), hydrogen storage tank (BHS, GHS), hydrogen fuel cell (HFC), and carbon capture (CC).

[0057] In the system of the present invention, the PEM, electric boiler, carbon capture equipment and electric load in the system are powered by the upper power grid and wind power; natural gas is mainly used to produce blue hydrogen; the carbon capture equipment is used to capture the carbon dioxide produced by natural gas hydrogen production; the hydrogen storage tank and the hydrogen fuel cell form a hydrogen energy conversion module, which converts hydrogen energy into electricity and heat energy for use by the load.

[0058] The experimental results in the above four scenarios are shown in Table 1.

[0059] Table 1 Comparison of cost results under different scenarios

[0060] As shown in Table 1, in terms of economic efficiency, Scenario 1, using green hydrogen alone, has the highest cost, while Scenario 2 and Scenario 3 both have lower costs. Scenario 4 has the lowest cost, reducing it by 1,188.3 yuan compared to Scenario 1. In terms of carbon emissions, Scenario 1 has the highest carbon emissions, while Scenario 2 and Scenario 3 both have lower carbon emissions. Scenario 4 has the lowest carbon emissions, reducing them by 74.53% compared to green hydrogen alone. In terms of new energy utilization efficiency, Scenario 1 has the highest utilization rate using green hydrogen alone, while Scenario 1 has the lowest utilization rate using blue hydrogen alone. Scenario 4 has the second highest utilization rate, while Scenario 2 and Scenario 3 have intermediate utilization rates, reducing them by 36.69% and 45.97%, respectively.

[0061] Based on the above data analysis, considering the dynamic supply mode of blue and green hydrogen and the role of flexible load can effectively reduce the system's carbon emissions and system costs, and significantly reduce system costs while sacrificing a relatively small utilization rate of new energy. In a single green hydrogen scenario, the main source of carbon emissions is electricity purchase from the upper power grid. Since hydrogen energy can only be produced through water electrolysis, the power generation of wind turbines cannot meet demand, and electricity purchase is required, resulting in a surge in carbon emissions and electricity purchase costs. After adding the blue and green hydrogen flexible supply mechanism, part of the hydrogen energy is obtained through gas-to-hydrogen production. At this time, the power generation of wind turbines can meet demand, that is, the purchase of electricity from the upper power grid is reduced, and carbon emissions and electricity purchase costs are reduced.

[0062] Analysis of Scenario 2 and Scenario 3 shows that the fixed-ratio hydrogen supply mechanism cannot effectively absorb wind power, making it unable to efficiently utilize wind power for hydrogen production during low-load periods. The dynamic ratio hydrogen supply mechanism can timely adjust the production ratio of blue and green hydrogen according to load changes, ensuring the efficient utilization of wind energy and helping to reduce the wind curtailment rate. However, the volatility of wind turbine power generation and the green hydrogen ratio limit both impose certain limitations on the energy supply side. Therefore, Scenario 4 considers further optimization from the energy consumption side, shifting flexible loads to different time periods, effectively reducing the wind curtailment rate. The wind turbine power generation can basically meet the system needs, and the amount of electricity purchased from the upper power grid is sharply reduced, with the purchase cost of electricity being only 2.51 yuan.

[0063] according to Figure 3 、 Figure 4 Analysis shows that for electricity load, the peak power consumption is higher during peak electricity consumption periods. By moving some of the transferable and replaceable electricity loads to other electricity consumption periods, the peak-to-valley difference in electricity consumption can be reduced by 22.91%, alleviating the electricity consumption pressure during peak periods.

[0064] Combine Figure 5 、 Figure 6 After optimization, electricity consumption increased between 01:00 and 07:00, and wind power-generated green hydrogen was insufficient to meet hydrogen load demand. Therefore, gas-generated blue hydrogen was added to supply this period. However, electricity consumption decreased between 18:00 and 22:00, and wind power-generated green hydrogen was able to meet hydrogen load demand. Consequently, blue hydrogen production during this period was significantly reduced, increasing the flexibility of hydrogen load supply. Regarding thermal loads, the power transferred was primarily concentrated between 1:00 and 5:00 and 18:00 and 23:00. Because the system's thermal energy supply during these different periods was generally sufficient to meet thermal loads, the transfer trend was smaller than that of electrical loads.

[0065] Depend on Figure 7 It can be seen that the changes in various satisfaction indicators are very small during the time periods of 0:00-7:00 and 15:00-17:00, indicating that the user power changes are small during this period, the power fluctuation of the EL equipment is small, and the equipment loss caused is small.

[0066] Combine Figure 4 It can be seen that there is power transfer in each period, so the user's electricity satisfaction is less than 1. Figure 3 The power consumption before and after optimization shows that the power changes greatly during the periods of 12:00-14:00 and 19:00-24:00, so the satisfaction during these periods decreases most significantly. In terms of price satisfaction, since part of the power during the peak period is transferred to the off-peak period, the electricity purchase price is significantly reduced. The satisfaction during the period of 8:00-22:00 is greater than 1, and the price satisfaction is highest during the periods of 12:00-14:00 and 19:00-22:00. In terms of EL equipment satisfaction, its value is related to the power fluctuation of EL equipment. The EL equipment satisfaction decreases during the periods of 7:00-11:00 and 21:00-22:00, indicating that its power fluctuation is large. Among them, the value drops sharply to 0 during the periods of 11:00 and 21:00, indicating that the electrolyzer has started and stopped, with the largest power fluctuation, resulting in large loss costs.

[0067] It can be seen that the introduction of flexible loads sacrifices some users' electricity satisfaction in exchange for higher price satisfaction, which helps to reduce the total cost of the system.

[0068] The present invention is based on an integrated energy system optimization scheduling method with a combined hydrogen production and demand response strategy. Compared with traditional integrated energy systems, the present invention optimizes the load curve on the load side and improves the flexibility of hydrogen supply by establishing a multi-element hydrogen production dynamic model and a flexible load model. At the same time, the model proposed by the present invention effectively reduces the system's carbon emissions, wind curtailment rate and total cost.

Claims

1. An integrated energy system optimization scheduling method based on combined hydrogen production and demand response strategy, characterized by The following steps are involved: Step 1: Build a hydrogen-containing integrated energy system model that includes an electrolyzer, gas-to-hydrogen equipment, an electric boiler, a hydrogen storage tank, a hydrogen fuel cell, and a heat storage device; Step 2: Construct a flexible load model and set satisfaction evaluation indicators; Step 3: Construct the output constraints and power balance constraints of each device in the hydrogen-containing integrated energy system model; Step 4: Establish an optimal scheduling model for the hydrogen-containing integrated energy system, with the minimum total cost as the optimization goal.

2. The integrated energy system optimization scheduling method based on combined hydrogen production and demand response strategy according to claim 1 is characterized by: In step 1, a hydrogen-containing integrated energy system model is first constructed. The hydrogen-containing integrated energy system is supplied by the energy supply side including the upper power grid, wind power, and natural gas grid; then, different types of energy are effectively coupled to the load through electric-thermal-hydrogen energy conversion; wherein, the energy conversion module includes hydrogen production, storage, and utilization modules, as well as electric boilers and heat storage devices; In the hydrogen-containing integrated energy system model, hydrogen energy is subdivided into blue and green hydrogen, which are used as energy media to couple electricity, heat, gas, and hydrogen energy; then, a model is established for each electrical equipment in the hydrogen-containing integrated energy system.

3. The integrated energy system optimization scheduling method based on combined hydrogen production and demand response strategy according to claim 2 is characterized by: Individual electrical equipment models include: 1) PEM water electrolysis hydrogen production model: （1）； In formula (1): for t Water consumption of EL equipment during the period; for t The amount of green hydrogen produced by EL equipment during the period; For EL devices t Electric power consumed during the time period; 、 、 They are the water consumption coefficient of EL equipment, the electricity-to-hydrogen conversion efficiency coefficient, and the lower calorific value of hydrogen; 、 They are the upper and lower limits of the power consumption of EL equipment respectively; Scheduling duration for the unit; 2) Natural gas hydrogen production model: The specific model of natural gas steam reforming combined with hydrogen production is as follows: （2）； In formula (2): for t The amount of blue hydrogen produced by G2H equipment during this period, for t The amount of natural gas consumed by the G2H equipment during the period; The efficiency of gas-to-hydrogen conversion of G2H equipment; is the lower calorific value of natural gas; for t Power consumption of G2H equipment during the time period; for t The amount of water consumed by the G2H equipment during the period; for t Carbon emissions generated by G2H equipment during the period; 、 、 They are the power consumption coefficient, water consumption coefficient, and carbon emission coefficient of the G2H equipment; 、 , respectively t The upper and lower limits of blue hydrogen production during a period; 、 They are t The upper and lower limits of natural gas intake volume during the period; 3) Electric boiler model: （3）； In formula (3): for t Heating power of EB equipment during the time period; for t The electric power consumed by the EB equipment during the time period; is the electrical-to-heat coefficient of the EB device; 、 They are the upper and lower limits of the power consumption of the EB equipment respectively; 4) Hydrogen storage model: （4）； In formula (4): for t The amount of hydrogen in the hydrogen storage tank during the period; for t Change in hydrogen storage during a period of time; 、 They are t The input and output of hydrogen storage tanks during each period; 、 is a binary variable, When it is 1, it indicates intake. When it is 1, it means exhalation; 、 Respectively represent the upper and lower limits of hydrogen storage in the hydrogen storage tank; 5) Hydrogen fuel cell model: （5）； In formula (5): 、 They are t The power generation and heat generation of HFC during the period; for t Hydrogen consumption during the period; 、 are the hydrogen-to-electricity coefficient and hydrogen-to-heat coefficient of hydrogen respectively; 、 are the upper and lower limits of hydrogen power generation respectively; 6) Heat storage device model: （6）； In formula (6): for t Heat storage capacity during the period; 、 They are t The heat injected and transferred out of the time period heat storage device; 、 are binary variables, among which When it is 1, it means heat is injected. When it is 1, it means heat is transferred out; 、 They are the upper and lower limits of heat storage of the heat storage device respectively.

4. The integrated energy system optimization scheduling method based on combined hydrogen production and demand response strategy according to claim 3 is characterized by: In step 2, the flexible loads are classified into Class I transferable loads, Class II replaceable loads, and Class III fixed loads. When the hydrogen-containing integrated energy system meets the demand for fixed loads, Class I transferable loads and Class II replaceable loads can adjust their own energy consumption levels. （7）； In formula (7): k Indicates the type of load, , Indicates the electrical load, represents the heat load, for t Time period k The total power of the load; for t Time period k Transferable loads of class loads; for t Time period k Replaceable loads for similar loads; for t Time period k Fixed load of type load.

5. The integrated energy system optimization scheduling method based on combined hydrogen production and demand response strategy according to claim 4 is characterized in that: Class I electric-thermal transferable loads are as follows: （8）； In formula (8): 、 Respectively k Type of load t The amount of Class I load after transfer and the amount involved in the transfer during the period; Indicates the k Type of load t The quantity before the transfer of Category I load in the time period; 、 They are t The power transfer-in and transfer-out values ​​of Class I loads during the time period; 、 is a binary variable, which is the kth load t The indicator quantity of the first category load transfer in the time period; 、 Respectively represent k Type of load t The upper and lower limits of the transfer power of Category I load in the time period; Indicates the scheduling period; It means that the transfer-in and transfer-out amounts of transferable load are conserved within a scheduling cycle.

6. The integrated energy system optimization scheduling method based on combined hydrogen production and demand response strategy according to claim 5 is characterized by: Category II electric-thermal replaceable loads are as follows: （9）； In formula (9): 、 Respectively t The power values ​​of the electric and thermal replaceable loads after time period substitution; 、 Respectively t The power value of the electric and thermal replaceable loads in the time period; 、 They are t Initial values ​​of the replaceable loads of electricity and heat for the time period; 、 Respectively t The power transferred in and out of the load that can be replaced by electricity during the period; 、 Respectively t The transfer-in and transfer-out power of the heat replaceable load during the time period; 、 Are binary variables, representing t The amount of load transfer in and out that can be replaced by electricity in a time period; 、 Are binary variables, representing t The transfer-in and transfer-out mark quantities of heat replaceable load in the time period; 、 Respectively t The power upper and lower limits of the load that can be regulated by the time period electricity; 、 Respectively t Time period heat can replace load to participate in the upper and lower limits of power regulation.

7. The integrated energy system optimization scheduling method based on combined hydrogen production and demand response strategy according to claim 6 is characterized by: In step 2, set the power transfer evaluation indicators for users and electrolyzer equipment: （10）； （11）； （12）； （13）； In the above formula: 、 、 These are the user satisfaction indicators for electricity consumption, price, and electrolyzer equipment; It represents the amount of Class I load participating in the transfer during the electric load period t; It indicates the amount of Class II load participating in the transfer during the electric load period t; represents the total amount of electric load during period t; for t The electricity purchase price for the time period; Before load change t Electricity consumption during the time period; for t The cost change due to load changes during a period is used to measure the satisfaction relationship between the user side and the energy supply side; represents the power of the electrolytic cell at time t+1; represents the power of the electrolytic cell at time t.

8. The integrated energy system optimization scheduling method based on combined hydrogen production and demand response strategy according to claim 7 is characterized by: In step 3, the output constraints and power balance constraints of each device in the hydrogen-containing integrated energy system model are constructed, including the following: 1) Electric power balance constraints: （14）； In formula (14): represents the purchased power during period t; represents the wind power consumption during period t; represents the power generation power of the green hydrogen cogeneration unit during period t; represents the power generation power of the blue hydrogen cogeneration unit during period t; for t Electricity load value of the time period; represents the power consumption of producing blue hydrogen during period t; represents the power consumption of the electrolytic cell during period t; It represents the power consumption of the electric boiler during period t; represents the power consumption of the carbon capture equipment during period t; 2) Thermal power balance constraints: （15）； In formula (15): for t Heat load value of the time period; represents the heat production power of the blue hydrogen cogeneration unit during period t; represents the heat production power of the green hydrogen cogeneration unit during period t; represents the heating power of the electric boiler during period t; Indicates the heat storage power of the heat storage device; Indicates the heat release power of the heat storage device; 3) Hydrogen supply and demand balance: （16）； In formula (16): 、 are the input and output of the green hydrogen storage tank respectively; 、 are the input and output of the blue hydrogen storage tank respectively; represents the hydrogen production of the electrolyzer during period t; It represents the hydrogen production of the gas-to-hydrogen equipment during period t; represents the hydrogen consumption of the green hydrogen cogeneration unit during period t; represents the hydrogen consumption of the blue hydrogen cogeneration unit during period t; represents the supply of green hydrogen to hydrogen load during period t; represents the supply of blue hydrogen to hydrogen load during period t; 4) Energy storage equipment constraints: It mainly constrains the input and output of energy storage equipment in each period: （17）； In formula (17): 、 Represent the initial and final values ​​of the equivalent charge state of different energy storage devices, where ; represents the minimum hydrogen storage rate of blue hydrogen during period t; represents the maximum hydrogen storage rate of blue hydrogen during period t; represents the minimum hydrogen storage rate of green hydrogen during period t; represents the maximum hydrogen storage rate of green hydrogen during period t; 、 They represent the hydrogen storage rates of green hydrogen and blue hydrogen during period t respectively; represents the minimum input power of the heat storage device during period t; represents the maximum input power of the heat storage device during period t; represents the heat storage power of the heat storage device during period t; 5) Wind power equipment constraints: To avoid damage to the unit, the output of the wind turbine must not exceed the unit's threshold: （18）； In formula (18): 、 They are the upper and lower limits of the fan output respectively; 6) Power purchase constraints: The system's purchase of electricity from the upper-level power grid must not exceed a certain threshold: （19）； In formula (19): 、 are the upper and lower limits of purchased power respectively; Represents the purchased electricity power during period t.

9. The integrated energy system optimization scheduling method based on combined hydrogen production and demand response strategy according to claim 8 is characterized by: In step 4, an optimization scheduling model for a hydrogen-containing integrated energy system is established, including a combined hydrogen production dynamic model and comprehensive consideration of carbon emission costs, wind curtailment costs, wind turbine operating costs, electrolyzer depreciation costs, blue hydrogen purification costs, flexible load compensation costs, and electricity purchase costs, with the goal of minimizing the total cost.

10. The integrated energy system optimization scheduling method based on combined hydrogen production and demand response strategy according to claim 9 is characterized in that: The step 4 comprises: 1) Dynamic model of combined hydrogen production: （20）； In formula (20): The total hydrogen load supply; 、 The supply of green hydrogen and blue hydrogen respectively; 、 are the proportion coefficients of green hydrogen and blue hydrogen respectively; The minimum supply ratio of green hydrogen; 2) Carbon emission costs: （21）； In formula (21): represents the cost of carbon emissions; represents the carbon emissions from producing blue hydrogen; represents the amount of CO2 collected by carbon capture; Indicates the scheduling period; is the base price of unit carbon emissions; 、 、 All are carbon emission factors of energy purchased at the upper level; for t The amount of electricity purchased from the upper power grid during the period; 3) Wind curtailment costs and wind turbine operating costs: （22）； In formula (22): represents the cost of wind curtailment and the operating cost of wind turbines; 、 are the actual power and maximum power of the wind turbine respectively; is the cost coefficient for wind turbine operation; is the unit wind curtailment cost factor; Indicates the scheduling period; 4) Energy purchase cost at the upper level: The system's upper-level energy purchase cost mainly consists of three parts: electricity purchase, gas purchase, and water purchase, which can be expressed as follows: （23）； In formula (23): represents the cost of purchased energy; represents the purchased power during period t; represents the blue hydrogen production during period t; represents the water consumption of the electrolytic cell during period t; Indicates the water consumption of hydrogen production from natural gas during period t; 、 、 They are the real-time electricity price, gas price and water price of the system respectively; 5) Cost of electrolyzer power fluctuation: （24）； In formula (24): represents the depreciation cost of the electrolytic cell; is the loss factor of the electrolytic cell caused by power fluctuation; 、 Represent the power of the electrolytic cell during period t and period t-1 respectively; 6) Blue hydrogen purification cost: （25）； In formula (25): represents the purification cost of blue hydrogen; is the purification cost coefficient of unit blue hydrogen; represents the production of blue hydrogen in period t; 7) Flexible load compensation cost: （26）； In formula (26): represents the compensation cost of flexible load; 、 are the unit compensation factors for transferable loads and replaceable loads, respectively; It represents the power of the kth load and the first type of load participating in the transfer during the t period; It represents the power replaced by the type II load in the kth load period t.

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