Optimized scheduling method for multi-energy coupling system containing electro-ammonia conversion

Abstract

The invention relates to an optimized dispatching method for a multi-energy coupling system containing electricity-ammonia conversion, and belongs to the field of optimized dispatching of power system operation. The economic and environment-friendly potential of ammonia energy in a multi-energy coupling system is excavated by carrying out refined modeling on equipment for converting ammonia into electricity, an ammonia fuel cell, ammonia energy storage and the like and considering the thermal power in the ammonia synthesis process. Combining the characteristics of the energy conversion equipment and the energy storage equipment to construct a mathematical model; and constructing an economic dispatching model of the multi-energy coupling system containing electro-ammonia conversion by taking the minimum comprehensive cost as a target. According to the multi-energy coupling system optimal scheduling method based on electro-ammonia conversion, the electro-ammonia conversion efficiency and efficient consumption and diversified utilization of renewable energy sources can be effectively improved.

Description

Technical Field

[0001] The present invention belongs to the field of optimal operation scheduling of power systems, and particularly relates to an optimal scheduling method for a multi-energy coupling system with power-ammonia conversion. Background Art

[0003] Due to the development and technological progress of wind and photovoltaic power generation, the installed capacity of wind and photovoltaic in China has accounted for 36.85% in 2024, and the proportion of renewable energy will continue to increase. Affected by the intermittency and uneven spatio-temporal distribution of renewable energy, the large-scale application of renewable energy is still restricted due to the lack of effective energy storage means at present. Some electrical energy storage methods, such as lithium batteries, flow batteries and supercapacitors, are difficult to meet the capacity or charge-discharge rate required for grid-scale storage. This has prompted the industry to conduct in-depth research on chemical energy carriers to meet the needs of safe, stable and large-scale storage of renewable energy. Green hydrogen is produced by electrolyzing water and is considered an ultimate clean fuel, which is expected to become an important driving factor for clean energy solutions. However, its low volumetric energy density, high storage cost brought about by its low boiling point, and explosion risk brought about by its flammability make it more challenging in engineering applications than traditional chemical energy storage carriers. To solve the problems related to hydrogen storage, researchers have proposed renewable synthetic products based on green hydrogen, such as methane, methanol and ammonia. Ammonia stands out among the alternatives due to its significant advantages such as low production cost, high energy density, rich hydrogen content, and easy storage and transportation. In the process of ammonia production, the synthesis of ammonia undergoes an exothermic chemical reaction. By effectively managing the heat released during the synthesis of ammonia and coupling the thermal energy to the heat load side, the energy supply mode of the system can be optimized, and the operation flexibility and overall energy utilization efficiency can be improved. In addition, in order to make ammonia more of an energy carrier rather than a storage medium, researchers have studied the utilization path of converting ammonia energy into electrical energy using ammonia fuel cells. However, the existing research on ammonia energy utilization only discusses a certain process of power-to-ammonia or ammonia fuel cells, and it is still necessary to explore whether it is feasible to integrate the power-ammonia conversion module into a multi-energy coupling system.

[0004] Therefore, integrating the power-ammonia conversion module into a multi-energy coupling system is of great significance for improving the electro-thermal flexibility of the system and the utilization efficiency of new energy. Summary of the Invention

[0005] The present invention proposes an optimized scheduling method for a multi - energy coupling system with electro - ammonia conversion. A multi - energy coupling system operation framework including an ammonia energy system is constructed, and the coordinated operation mechanism of each device in the multi - energy coupling system is analyzed; meanwhile, the operation mechanism and energy conversion relationship of the ammonia synthesis system are studied, and the system characteristics of the coordinated operation of electro - ammonia production and ammonia fuel cells are explored in combination with DAFC technology; based on the characteristics of energy coupling devices and energy storage devices, relevant mathematical models are constructed. In addition, an optimized scheduling model with the lowest total operation cost of the multi - energy coupling system with electro - ammonia conversion as the objective function is constructed to form an overall solution that can flexibly respond to the fluctuations of renewable energy, improving the economy and flexibility of the multi - energy coupling system.

[0006] The beneficial effects of the present invention are as follows: The optimized scheduling method for the multi - energy coupling system with electro - ammonia conversion involved in the present invention realizes the refined utilization of ammonia energy through the ammonia energy system mainly composed of ammonia synthesis - ammonia storage tank - ammonia fuel cell and the thermal power in the ammonia synthesis process, which is beneficial to improving the electro - thermal flexibility of the system and the utilization efficiency of new energy. In addition, the introduction of the energy storage unit effectively realizes the time - shift of clean energy. Brief Description of the Drawings

[0007] Figure 1 It is the flowchart of the optimized scheduling method for the multi - energy coupling system with electro - ammonia conversion of the present invention;

[0008] Figure 2 It is the framework diagram of the multi - energy coupling system with electro - ammonia conversion of the present invention;

[0009] Figure 3 It is the structure diagram of the ammonia energy comprehensive utilization system of the present invention;

[0010] Figure 4 It is the prediction curve graph of wind power, photovoltaic power, electric load and heat load of the present invention;

[0011] Figure 5 It is the electric power scheduling result graph of the multi - energy coupling system with electro - ammonia conversion of the present invention;

[0012] Figure 6 It is the thermal power scheduling result graph of the multi - energy coupling system with electro - ammonia conversion of the present invention;

[0013] Figure 7 It is the gas power scheduling result of the multi - energy coupling system with electro - ammonia conversion of the present invention. Detailed Embodiments

[0014] An optimization scheduling method for a multi - energy coupling system with electro - ammonia conversion. The technical solution of the present invention is based on the framework of a multi - energy coupling system with electro - ammonia conversion. Around the four units of energy supply, coupling, energy storage, and energy consumption, the mathematical models of key equipment are constructed in detail, and the operating mechanism of the ammonia - energy system is systematically analyzed. Through the modeling of core links of green ammonia such as water electrolysis for hydrogen production, air separation for nitrogen production, and Haber - Bosch ammonia synthesis, as well as the dynamic regulation processes of electric energy storage, thermal energy storage, and ammonia energy storage systems, an overall solution that can flexibly respond to the fluctuations of renewable energy is formed. In addition, an optimization scheduling model with the lowest total operating cost of the multi - energy coupling system with electro - ammonia conversion as the objective function is constructed. Through simulation, the effectiveness of the optimization scheduling method for the multi - energy coupling system with electro - ammonia conversion proposed by the present invention in improving the electro - ammonia conversion efficiency and the efficient consumption and diversified utilization of renewable energy is verified.

[0015] As Figure 1 shown, the flow chart of the low - carbon scheduling method for the multi - energy coupling system considering electro - ammonia conversion and demand response proposed by the present invention specifically includes the following steps:

[0016] 1) Constructed an operating framework for a multi - energy coupling system with electro - ammonia conversion around the four units of energy supply, coupling, energy storage, and energy consumption; 2) Explored the operating mechanism and energy conversion relationship of the ammonia - energy synthesis system, discussed the system characteristics of the coordinated operation of electro - ammonia production and ammonia fuel cells in combination with Direct Ammonia Fuel Cell (DAFC) technology, and constructed relevant mathematical models based on the characteristics of energy coupling equipment and energy storage equipment; 3) Constructed an economic scheduling model for a multi - energy coupling system with electro - ammonia conversion with the goal of minimizing the comprehensive cost; 4) Obtained the operating parameters of the multi - energy coupling system and the predicted values of wind - light - load; 5) Solved the established economic scheduling model for the multi - energy coupling system with electro - ammonia conversion to obtain the optimal scheduling plan.

[0017] The implementation method is specifically elaborated as follows:

[0018] 1. Construction of the multi - energy coupling system framework considering electro - ammonia conversion

[0019] The operating framework of the multi - energy coupling system considering electro - ammonia conversion constructed in this paper is as Figure 2As shown in the figure. The multi - energy coupling system mainly includes 4 units, namely the energy supply unit, the energy coupling unit, the energy storage unit, and the energy consumption unit. The energy supply unit includes a wind farm, a photovoltaic power station, the superior power grid, and the superior heat network; the energy coupling unit includes an ammonia energy synthesis system composed of an electrolyzer (EL), pressure swing absorption (PSA) for nitrogen production, P2A, a combined heat and power (CHP) unit, an electrical boiler (EB), and a direct ammonia fuel cell (DAFC); the energy storage unit includes electrical energy storage, thermal energy storage, and ammonia energy storage; the energy consumption unit includes an electrical load and a thermal load.

[0020] 2. Construction of the ammonia energy comprehensive utilization system model

[0021] The structure of the ammonia energy comprehensive utilization system with electro - thermal - ammonia coupling proposed by the present invention is as Figure 3 shown. The primary task of renewable energy is to meet the electricity demand. The surplus renewable energy electricity is consumed by the ammonia energy synthesis system, stored in the form of ammonia energy, and the DAFC is used to relieve the energy supply pressure during peak electricity consumption.

[0022] The technical route of green electricity - based ammonia production mainly includes four key units, namely the water electrolysis unit for hydrogen production, the cryogenic air separation unit for nitrogen production, the Haber - Bosch thermochemical ammonia synthesis unit, and the thermal power recovery and utilization unit. The core of P2A is the water electrolysis unit for hydrogen production driven by renewable energy. The combination of renewable energy - based hydrogen production and the Haber - Bosch process can avoid the use of fossil fuels, solve the problem of large - scale surplus renewable energy, and improve the penetration rate of renewable energy power generation facilities. Nitrogen is produced by the PSA device to supply gaseous nitrogen supplement flow to the ammonia synthesis device, which is regarded as a sub - device of the ammonia synthesis device. Then, through the Haber - Bosch process, hydrogen and nitrogen are synthesized into ammonia in the ammonia synthesis reactor (ASR) and stored for later use.

[0023] In the ASR, nitrogen reacts with hydrogen in an exothermic equilibrium reaction:

[0024] When there is a power shortage due to insufficient supply or a surge in demand, ammonia is used as the fuel of a solid oxide fuel cell as a backup power source in the system. The main anode and cathode reactions in the ammonia fuel cell:

[0025] Anode:

[0026] Cathode:

[0027] As the penetration of renewable energy continues to increase, the negative impact of intermittent renewable energy is also increasing. The entire process of the electricity-ammonia conversion pathway can be regarded as a flexible method to mitigate the negative impact of intermittent renewable energy. The heat generated by the system is well recovered, and the waste heat is used to supply regional heat loads.

[0028] (1) EL model: The electrolysis of water to produce hydrogen is usually composed of multiple hydrogen generators. Advanced control strategies and unit combinations can be used to improve the flexible adjustment capabilities of the hydrogen production equipment, thereby adapting well to the volatility of renewable energy generation. The EL model is as follows:

[0029] Where: for t Hydrogen production during the period; for t The electric power consumed by EL during the time period; is the conversion efficiency of EL; 、 are the upper and lower limits of EL input power respectively; 、 They are the maximum allowable uphill and downhill climbing powers of EL respectively.

[0030] (2) PSA model: PSA is widely used in nitrogen production due to its high efficiency and low operating and maintenance costs. To reduce the power consumption of PSA, the nitrogen production is adjusted according to the hydrogen production rate of EL, where the power consumption of PSA is proportional to the hydrogen production rate. The PSA model is as follows:

[0031] Where: for t The electric power consumed during the nitrogen production process in this period; for t Nitrogen production during the period; is the molar mass of air; is the ideal gas constant; is the temperature corresponding to the nitrogen production process; 、 are the PSA inlet and outlet pressures, respectively; For the overall efficiency of PSA; 、 They are the upper and lower limits of the electric energy input power of PSA respectively.

[0032] (3) P2A model: P2A is an innovative technology that uses renewable energy for ammonia synthesis and can achieve an ammonia synthesis rate close to 100% under standard conditions (180 °C, 300 bar). By tracking the hydrogen production rate of EL, ASR can adjust the ammonia production rate, thereby optimizing power consumption, where the power consumption of ASR is proportional to the hydrogen production rate. In addition, the heat released during the ammonia synthesis process can be effectively coupled to the heat load side, further optimizing the energy supply, improving the overall energy utilization efficiency, and enhancing the operation flexibility of the system. The model of P2A is as follows:

[0033] Where: is t the ammonia production during the time period; is t the electric power consumed during the ammonia production process in the time period; is the efficiency of ammonia synthesis; is t the thermal power provided to the system during the ammonia synthesis process in the time period; is the heat release efficiency of the thermal power provided by the ammonia production plant; is the thermal power released per unit of ammonia synthesis; the mass ratio of ammonia, nitrogen, and hydrogen is 0.097:0.107:1, and the volume ratio is 2:1:3. Under standard conditions, 1 kg of hydrogen is approximately 11.2 ; and are the upper and lower limits of the electric energy input power of the ammonia synthesis equipment, respectively; and are the upper and lower limits of the ramp power of the ammonia synthesis equipment, respectively.

[0034] (4) Ammonia energy storage model: The ammonia production by electrolysis is affected by the fluctuations of wind and solar power generation, which easily makes the operation of the ammonia energy utilization system unstable. Ammonia energy storage ensures the smoothness of the production process by smoothly adjusting the ammonia production rate and reducing the variable load regulation pressure during the ammonia synthesis process

[79] . To meet the regulation requirements of the multi-energy coupling system for ammonia energy, the established ammonia energy storage model is as follows:

[0035] Where: and are t the charging and discharging powers of ammonia energy storage during the time period, respectively; and are t the 0-1 variables of the charging and discharging states of ammonia energy storage during the time period, respectively; and are the maximum values of the charging and discharging powers of ammonia energy storage, respectively; is t the total power of ammonia energy storage during the time period; is the gas constant of ammonia; is the ambient temperature; is the unit calorific value of ammonia under standard conditions; is t the load state of ammonia energy storage during the is the installed capacity of ammonia energy storage; and are the upper and lower limits of the load state of ammonia energy storage, respectively.

[0036] (5) Direct ammonia fuel cell model: DAFC can directly use ammonia or aqueous ammonia as the main reactant, and convert the chemical energy of ammonia or aqueous ammonia into electrical energy through chemical reactions. Compared with indirect ammonia fuel cells, DAFC directly utilizes the chemical energy of ammonia, eliminates the need for ammonia decomposition, reduces system complexity and operating costs, and has good application prospects. The DAFC model is as follows:

[0037] Where: is t the electric power generated by DAFC during the is t the mass of ammonia input to DAFC during the is the electrical conversion efficiency of DAFC; and are the upper and lower limits of the hydrogen energy input power of DAFC, respectively; and are the upper and lower limits of the ramping power of DAFC, respectively.

[0038] 3. Multi-energy coupling system equipment model.

[0039] (1) CHP model: CHP has the advantages of fast response speed, flexible start-stop, and excellent environmental performance. In the multi-energy coupling system, as an important electricity-heat coupling device, CHP needs to meet the demands of both electric energy and heat energy simultaneously, and flexibly adjust its operation output according to the fluctuations of wind and solar power generation. The CHP model is as follows:

[0040] Where: is t the natural gas power consumed by CHP during the and are t the electric and heat powers output by CHP during the and is the electric-heat conversion efficiency of CHP; and They are the upper and lower limits of the natural gas input power of the CHP, respectively. , They are the upper and lower limits of the ramping power of the CHP, respectively.

[0041] (2) EB model: EB can utilize the surplus wind and solar power output or the electric energy purchased at off-peak electricity prices, and efficiently convert it into heat energy to meet the heat load demand. Compared with gas boilers, EB has the advantages of zero emissions, high control accuracy, and low maintenance costs, and can achieve clean and efficient heating, optimizing the energy utilization structure. The model of EB is as follows:

[0042] In the formula: is t the electric power consumed by EB in period is t the heat power output by EB in period is the conversion efficiency of EB; , They are the upper and lower limits of the natural gas input power of the CHP, respectively; , They are the upper and lower limits of the ramping power of the CHP, respectively.

[0043] (3) Electrical energy storage model: Electrical energy storage can store the surplus electrical energy and release it during peak demand. It can flexibly respond to time-of-use electricity prices and meet the electrical load demand through the mechanism of storing at low prices and discharging at high prices. The model of electrical energy storage is as follows:

[0044] In the formula: , are the 0 / 1 integer variables of the charge and discharge states of the electrical energy storage, respectively; , are t the charge and discharge powers of the electrical energy storage in period , are the maximum values of the charge and discharge powers of the electrical energy storage to the outside, respectively; , are the charge and discharge efficiencies of the electrical energy storage, respectively; is the installed capacity of the electrical energy storage; , are the upper and lower limits of the state of charge of the electrical energy storage, respectively; the state of charge should be equal at the beginning and end of an optimization period T.

[0045] (4) Thermal energy storage model: In a multi - energy coupling system, the peak - valley periods of different load types often do not coincide, making it difficult for combined heat and power equipment to simultaneously meet the heating and electrical demands. In response to this mismatch between heating and electrical demands, introducing a thermal energy storage device is an effective solution. Considering the heat loss of the thermal energy storage itself, the model of the thermal energy storage is as follows:

[0046] In the formula: 、 are 0 - 1 variables for the charging and discharging states of the thermal energy storage respectively; 、 are respectively t the charging and discharging power of the thermal energy storage during the period; 、 are respectively the maximum values of the charging and discharging power of the thermal energy storage to the outside; 、 are respectively the charging and discharging efficiencies of the thermal energy storage; is the self - discharging coefficient of the thermal energy storage; is the installed capacity of the thermal energy storage; 、 are respectively the upper and lower limits of the load state of the thermal energy storage; the load state should be equal at the beginning and end of an optimization period T.

[0047] 5. Economic dispatch model of the multi - energy coupling system.

[0048] (1)Objective function: Taking the minimum total operating cost of the multi - energy coupling system as the objective function, and on this basis, converting the curtailment of wind and solar power into penalty costs and including them in the operating cost of the system. Its dispatch plan model is as follows:

[0049] In the formula: is the total cost of the multi - energy coupling system; is the energy procurement cost of the multi - energy coupling system; is the operation and maintenance cost of the multi - energy coupling system; is the start - stop cost of the multi - energy coupling system; is the penalty cost for wind and solar curtailment of the multi - energy coupling system.

[0050]

[0051] In the formula: 、 and are respectively t the unit cost coefficients of electricity, heat, and gas purchased by the system during the period; 、 and are respectively tThe electricity purchase power, heat purchase power and gas purchase volume of the time period system; is the unit operation and maintenance cost coefficient of the th unit; is t the output of the th unit in the N time period, where ; , , , and are the start-up costs of EL, P2A, DAFC, CHP and EB respectively; , , , and are the shutdown costs of EL, P2A, DAFC, CHP and EB respectively; , , , and are respectively t the start-up status of EL, P2A, DAFC, CHP and EB in the , , , and are respectively t the shutdown status of EL, P2A, DAFC, CHP and EB in the and are the unit cost coefficients of wind curtailment and PV curtailment respectively; and are respectively t the wind curtailment and PV curtailment volumes in the

[0052] (2) Constraints: 1) Wind turbine and PV output constraints.

[0053]

[0054] In the formula: , are the wind turbine and PV outputs in the t time period; , are the upper limits of wind turbine and PV outputs.

[0055] 2) Electric power balance constraint.

[0056]

[0057] 3) Heat power balance constraint.

[0058]

[0059] Wherein: and are respectively t the electric and heat load powers during the time period.

[0060] 4) Unit start-stop constraint.

[0061]

[0062] Wherein: ; and are respectively t the start-stop states of the unit during the time period and t the -1 time period. [[ID=3l]] i of the unit.

[0063] 6. Solve the established low-carbon optimal scheduling model of the ammonia-containing multi-energy coupling system to obtain the optimal scheduling plan.

[0064] (1) Parameter setting: In the present invention, the operation framework of the multi-energy coupling system shown in Figure 2 is adopted to verify the effectiveness of the proposed economic scheduling model of the multi-energy coupling system with electric-ammonia conversion. The predicted values of wind power generation, photovoltaic power generation, electric load and heat load of the multi-energy coupling system are as shown in Figure 4 . The heat purchase price is 200 yuan / MW×h; the purchase price of natural gas is 350 yuan / MW×h; the penalty cost for wind and light abandonment is 300 yuan / MW×h. The time-of-use electricity price is shown in Table 1.

[0065] Table 1 Time-of-use electricity price table Time period Electricity price (yuan / kW·h) 00:00-05:00，22:00-24:00 0.358 05:00-09:00，13:00-17:00 0.741 09:00-13:00，17:00-22:00 1.031

[0066] (2) Analysis of the scheduling results of the multi-energy coupling system:

[0067] In this paper, the optimal scheduling of the system economic scheduling model is solved under the predicted values of wind power generation, photovoltaic power generation, electric load and heat load of the multi-energy coupling system, and the scheduling results are as shown in Figures 5 - 7 .

[0068] From Figure 5It can be seen that during the time periods of 00:00 - 06:00 and 23:00 - 24:00, the combined output of wind and solar power in the power system is at its peak, while the electricity load level is relatively low. At this time, the wind and solar power generation units serve as the main energy supply equipment, and the electrical energy storage is in the charging state. EL, PSA, and P2A cooperate together as flexible adjustable equipment and operate at a relatively high level, and the storage of ammonia energy is achieved through the ammonia storage tank to improve the high-level consumption of wind and solar resources; during the time periods of 11:00 - 14:00 and 18:00 - 22:00, the combined output of wind and solar power is at a low ebb, while the electricity load is at the peak period, and the supply capacity of renewable energy is insufficient. At this time, DAFC conducts ammonia-electricity conversion through the ammonia gas released from the ammonia storage tank, and the electrical energy storage discharges at the initial stage of DAFC ramping to relieve the power supply pressure during the peak period of the electricity load.

[0069] It can be seen from Figure 6 the thermal energy scheduling results shown that the thermal energy generated by the P2A device during the process of realizing the coupling of electricity and ammonia supplies part of the thermal load, which can reduce the output of EL and CHP at the same moment, relieve the energy supply pressure of the heating equipment during the peak period of the thermal load, and reduce the consumption of electric energy and natural gas, improving the economy and environmental protection of the thermal scheduling.

[0070] Combined with Figure 5 and Figure 7 it can be seen that the operating levels of P2A and DAFC show reverse characteristics and forward characteristics respectively compared with the electricity load curve, that is, during the peak period of the electricity load, P2A operates at a lower level and DAFC operates at a higher level; during the low ebb period of the electricity load, P2A operates at a higher level and DAFC operates at a lower level. At the same time, P2A can better track the output of wind power and photovoltaic power, achieve the full consumption of wind and solar power output, and improve the economy of system operation.

[0071] 7. Conclusion.

[0072] Through comprehensive analysis of the optimization scheduling results of electric energy, thermal energy, and ammonia energy, it can be found that the P2A device converts the excess wind and solar power output into ammonia gas, provides heat to the thermal energy system during the process of electricity-ammonia conversion, reduces the energy consumption of the thermal energy system, and injects the converted ammonia gas into the ammonia storage tank for storage. When necessary, it delivers clean electricity to the power system through the fuel cell. On this basis, the P2A device coordinates the operation between the power system and the thermal energy system. It can be clearly seen that the P2A device can improve the consumption rate of wind and solar resources in the multi-energy coupling system and achieve the goal of efficiently using clean energy and reducing the system operation cost through multi-energy coupling. Therefore, when renewable energy is sufficient, the operating level of P2A should be increased as much as possible.

Claims

1. An optimal scheduling method for a multi - energy coupling system with electro - ammonia conversion, characterized in that Specifically, it includes the following steps: 1) A multi - energy coupling system operation framework with electro - ammonia conversion is constructed around four units: energy supply, coupling, energy storage, and energy consumption; 2) Explore the operation mechanism and energy conversion relationship of the ammonia energy synthesis system. Combining with the Direct Ammonia Fuel Cell (DAFC) technology, discuss the system characteristics of the coordinated operation of ammonia synthesis and ammonia fuel cell. And based on the characteristics of energy coupling equipment and energy storage equipment, construct relevant mathematical models; 3) With the goal of minimizing the comprehensive cost, construct an economic dispatch model of the multi - energy coupling system with electro - ammonia conversion; 4) Obtain the operation parameters of the multi - energy coupling system and the predicted values of wind - light - load; 5) Solve the established economic dispatch model of the multi - energy coupling system with electro - ammonia conversion to obtain the optimal dispatch plan.

2. The optimal scheduling method for a multi-energy coupling system with electro-ammonia conversion according to claim 1, characterized in that In step 1), the operation framework of the multi - energy coupling system with electro - ammonia conversion mainly includes 4 units, namely the energy supply unit, the energy coupling unit, the energy storage unit, and the energy consumption unit. The energy supply unit includes a wind farm, a photovoltaic power station, the superior power grid, and the superior heat network; the energy coupling unit includes an ammonia energy synthesis system composed of an electrolyzer (EL), pressure swing absorption (PSA), Power - To - Ammonia (P2A), a combined heat and power (CHP) unit, an electrical boiler (EB), and a DAFC; the energy storage unit includes electrical energy storage, thermal energy storage, and ammonia energy storage; the energy consumption unit includes an electrical load and a thermal load.

3. The optimal scheduling method for the multi-energy coupling system with electro-ammonia conversion according to claim 1, characterized in that In step 2), the primary task of renewable energy in the multi - energy coupling system with electro - ammonia conversion is to meet the electricity demand. The surplus renewable energy electricity is consumed by the ammonia energy synthesis system, and then stored in the form of ammonia energy. And during the peak electricity consumption period, the DAFC is used to relieve the energy supply pressure. Also, by effectively managing the heat released during the P2A process and coupling the thermal energy to the thermal load side, the energy supply mode of the system can be optimized. At the same time, according to the characteristics of the key energy conversion devices and energy storage equipment in the multi - energy coupling system, construct mathematical models of EL, PSA, P2A, CHP, EB, DAFC, electrical energy storage, thermal energy storage, and ammonia energy storage.

4. The optimal scheduling method for the multi-energy coupling system with electro-ammonia conversion according to claim 1, wherein, In step 3), when establishing the economic dispatch model of the multi - energy coupling system with electro - ammonia conversion, the minimum total system operation cost is used as the objective function, where the total cost includes the electricity purchase cost, gas purchase cost, heat purchase cost, equipment operation and maintenance cost, equipment start - up and shut - down cost, and the penalty cost converted from the curtailment of wind and solar power. And construct constraint conditions such as electrical - thermal power constraints, wind - light output constraints, and equipment start - up and shut - down constraints to improve the consumption and diversified utilization level of renewable energy in the multi - energy coupling system.

5. The optimal scheduling method for a multi-energy coupling system with electro-ammonia conversion according to claim 1, characterized in that, In step 4), obtain the time - of - use electricity price, gas purchase, heat purchase, and curtailment of wind and solar power penalty cost operation parameters of the multi - energy coupling system, as well as the predicted values of wind power generation, photovoltaic power generation, electrical load, and thermal load.

6. The optimal scheduling method for the multi-energy coupling system with electro-ammonia conversion according to claim 1, wherein In step 5), the economic dispatch model of the multi-energy coupling system with power-to-ammonia conversion is solved to obtain the optimal dispatch plan. Through the constructed operation framework of the multi-energy coupling system with power-to-ammonia conversion, the present invention verifies the effectiveness of the proposed method in improving the consumption and diversified utilization level of renewable energy, fully exploits the flexibility and environmental friendliness of the ammonia energy utilization system, and improves the economy of the multi-energy coupling system.

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