Regional comprehensive energy system dispatching method and system considering gravity energy storage participation

Abstract

The application discloses a regional comprehensive energy system dispatching method and system considering gravity energy storage participation, and relates to the technical field of power dispatching.The technical scheme is as follows: a gravity energy storage device is configured in a regional comprehensive energy system, and a dynamic coupling dispatching model between the gravity energy storage, wind power and load is established; the gravity energy storage device is controlled to store energy in a wind power surplus period at night through the dynamic coupling dispatching model, and the gravity energy storage device is controlled to release energy in a peak load period, so that bidirectional regulation and control of abandoned wind power and power supply gaps are realized; an optimization dispatching model containing the gravity energy storage device is constructed with a minimum system periodic operation cost as an objective function, and optimal operation parameters of each device in a dispatching period are output.The application realizes full consumption of wind power, reduces the total operation cost through optimization dispatching, and makes up for defects of the prior art, such as geographical limitations on the source side, poor implementation effect on the load side and insufficient economy on the storage side.

Description

Technical Field

[0001] This invention relates to the field of power dispatching technology, and more specifically, to a method and system for dispatching regional integrated energy systems that takes into account the participation of gravity energy storage. Background Technology

[0002] Regional integrated energy systems, by integrating multiple energy forms such as electricity, heat, and gas, can achieve energy complementarity and efficiency improvement. However, during the heating season, due to the significant differences in peak and off-peak characteristics of electricity and heat loads, the system faces a severe challenge in wind power absorption. During peak nighttime heat load periods, gas turbines need to maintain high power output to meet heating demand; this "heat-driven power generation" operating mode squeezes out the grid-connected space for wind power. At the same time, wind power itself has anti-peak-shaving characteristics, generating more electricity during off-peak nighttime periods. The combination of these two factors leads to a large amount of wind curtailment, which not only wastes renewable energy but also increases the system's operating costs and environmental burden. Actual operating data shows that this problem is particularly prominent in northern heating areas.

[0003] Currently, the main technical approaches to addressing wind power integration include source-side multi-energy complementarity, load-side demand response, and various energy storage devices on the storage side. On the source side, multi-energy complementarity is achieved by introducing renewable energy sources such as geothermal and biomass energy; however, the application of these energy sources is severely limited by geographical conditions and resource distribution. On the load side, electricity price-based demand response or integrated demand response strategies are used to guide load shifting; however, the actual implementation effectiveness is constrained by users' energy consumption habits and willingness. On the storage side, while technologies such as electrochemical energy storage and power-to-gas (PTO) have some application, they have significant limitations: electrochemical energy storage has a short lifespan and faces significant environmental challenges after decommissioning; large-scale PTO and other energy storage devices have high investment costs and limited energy conversion efficiency. These existing technologies are insufficient in terms of economics, applicability, and environmental friendliness, making it difficult to efficiently solve the wind power integration problem during the heating season.

[0004] Gravity energy storage, as an emerging mechanical energy storage technology, stores and releases energy by lifting and lowering heavy objects, offering significant technical and economic advantages. Compared to pumped hydro storage, gravity energy storage has a shorter construction cycle and is not limited by specific geographical conditions; compared to electrochemical energy storage, it features a longer lifespan, environmental friendliness, and higher safety. However, the potential of gravity energy storage in participating in multi-energy complementary optimization within regional integrated energy systems has not yet been fully explored, particularly its value in the two-way regulation of wind curtailment and power supply gaps during economic dispatch requires further in-depth research. Therefore, it is necessary to develop optimized dispatch methods for regional integrated energy systems incorporating gravity energy storage to fully leverage its technological advantages and enhance the system's wind power absorption capacity. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a regional integrated energy system dispatching method and system that incorporates gravity energy storage. By introducing gravity energy storage devices and establishing a dynamic coupled dispatching model, bidirectional regulation of wind power curtailment and power supply gaps can be achieved. During nighttime periods of surplus wind power, gravity energy storage responds to wind power curtailment, effectively reducing wind power waste. During peak electricity load periods, gravity energy storage releases energy to regulate power supply gaps, reducing the system's dependence on the main grid. This not only improves the utilization rate of renewable energy and achieves full wind power consumption, but also reduces the total operating cost through optimized dispatching, thus overcoming the shortcomings of existing technologies, such as geographical limitations on the source side, poor implementation effect on the load side, and insufficient economic efficiency on the storage side.

[0006] The above-mentioned technical objective of the present invention is achieved through the following technical solution: Firstly, a regional integrated energy system dispatching method considering the participation of gravity energy storage is provided, including the following steps: By configuring gravity energy storage devices in a regional integrated energy system, and based on the low storage and high generation characteristics of the gravity energy storage devices, a dynamic coupling scheduling model between gravity energy storage, wind power and load is established. Through the dynamic coupling scheduling model, the gravity energy storage device is controlled to store energy during the nighttime wind power surplus period to respond to wind curtailment, and the gravity energy storage device is controlled to release energy during the peak electricity load period to adjust the power supply gap, thereby realizing bidirectional regulation of wind curtailment and power supply gap. With minimizing the system cycle operating cost as the objective function, an optimized scheduling model incorporating the gravity energy storage device is constructed. An optimization solver is then used to solve the optimized scheduling model, outputting the optimal operating parameters of each device within the scheduling cycle.

[0007] Furthermore, the cost component in the objective function includes gas consumption cost, unit operation and maintenance cost, environmental pollution control cost, wind curtailment penalty cost, electricity purchase cost, electricity sales revenue, and the daily investment and construction cost of the gravity energy storage device; The objective function is expressed as minimizing the algebraic sum of all cost components; The electricity purchase cost and the electricity sales revenue are calculated through the power exchange between the system and the main grid via the tie line.

[0008] Furthermore, the electricity purchase cost and the electricity sales revenue are calculated through power exchange via the tie line between the system and the main grid, including: The electricity purchase cost is calculated based on the electricity purchase power variable in the interconnection power of the tie line; The electricity sales revenue is calculated based on the electricity sales power variable in the interconnection power of the tie line. The power purchase power variable and the power sales power variable are decision variables in the optimized scheduling model, and are determined by solving the model.

[0009] Furthermore, the calculation of the environmental pollution control cost includes: Calculate the emissions of sulfur dioxide, carbon dioxide, and nitrogen oxides based on the power generated by the gas turbine and the power purchased from the main grid. The environmental pollution control cost is obtained by multiplying the emission amount of each pollutant by the corresponding unit treatment cost and then summing the results.

[0010] Furthermore, the constraints of the optimized scheduling model include: The power supply and demand balance constraint is configured such that the sum of power generation, energy storage, and interconnection power equals the power load. The thermal energy supply and demand balance constraint requires that the heating power be equal to the heat load power. The operational constraints of the gravity energy storage device are configured to include upper and lower limits of energy storage, height variation constraints during energy storage and release phases, and energy storage equalness constraints at the beginning and end of the scheduling cycle. The system interacts with the main grid to constrain power consumption, and is configured to limit the power purchased and sold to a preset upper limit.

[0011] Furthermore, the constraints of the optimized scheduling model also include: The controllable unit output operation constraints are configured as upper and lower limit constraints for gas turbine output. The controllable unit ramp-up operation constraint is configured as the gas turbine ramp-up power limit; Battery operation constraints are configured as state of charge constraints, output constraints, and equal charge level throughout the cycle. Network operation constraints are configured as power network flow constraints and natural gas network flow constraints.

[0012] Furthermore, the physical model configuration of the gravity energy storage device is as follows: The energy storage power of the gravity energy storage device is equal to its energy storage efficiency multiplied by its mass, gravitational acceleration, and the change in height during the energy storage stage. The energy release power of the gravity energy storage device is equal to its energy release efficiency multiplied by the change in energy storage during the energy release stage. The change in altitude is limited by the maximum change value during the energy storage and energy release phases, respectively.

[0013] Furthermore, the method also includes: This enables the gravity energy storage device and the battery pack to operate in a complementary capacity and coordinated fast and slow operation mode; During peak wind power periods at night, the gravity energy storage device and the battery pack work together to perform energy storage operations, so as to smooth wind power fluctuations and promote full wind power consumption. During peak electricity load periods, the gravity energy storage device releases energy at a constant power, while the battery pack responds quickly to fill the load gap.

[0014] Furthermore, the optimization solver is CPLEX software; Specifically, the nonlinear constraints in the optimized scheduling model are transformed into linear constraints by performing piecewise linearization, and then solved using the CPLEX software.

[0015] Secondly, a regional integrated energy system dispatching system that takes gravity energy storage into account is provided, including gravity energy storage devices, wind power generation equipment, load equipment, gas turbines, battery packs, tie lines connected to the main grid, and control devices. The control device is configured to: Based on the low storage and high generation characteristics of the gravity energy storage device, a dynamic coupling scheduling model between gravity energy storage, wind power and load is established. Through the dynamic coupling scheduling model, the gravity energy storage device is controlled to store energy during the nighttime wind power surplus period to respond to wind curtailment, and the gravity energy storage device is controlled to release energy during the peak electricity load period to adjust the power supply gap, thereby realizing bidirectional regulation of wind curtailment and power supply gap. With minimizing the system cycle operating cost as the objective function, an optimized scheduling model including the gravity energy storage device is constructed, and an optimization solver is used to solve the optimized scheduling model to output the optimal operating parameters of each device within the scheduling cycle, wherein the device includes the gas turbine, the battery pack and the tie line.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The regional integrated energy system dispatching method considering gravity energy storage provided by this invention introduces gravity energy storage devices and establishes a dynamic coupled dispatching model to achieve bidirectional regulation of wind curtailment power and power supply gap. During the nighttime surplus wind power period, gravity energy storage responds to wind curtailment power, effectively reducing wind power waste; during peak electricity load periods, gravity energy storage releases energy to regulate the power supply gap, reducing the system's dependence on the main grid. This not only improves the utilization rate of renewable energy and achieves full wind power consumption, but also reduces the total operating cost through optimized dispatching, making up for the shortcomings of existing technologies such as source-side geographical limitations, poor implementation effect on the load side, and insufficient economic efficiency on the storage side. 2. This invention optimizes the design of objective functions including gas consumption costs, unit operation and maintenance costs, environmental pollution control costs, wind curtailment penalty costs, electricity purchase costs, electricity sales revenue, and daily investment and construction costs of gravity energy storage, and constructs a comprehensive economic optimization model: by minimizing the algebraic sum of all cost components, the economic efficiency of system operation is ensured; in addition, electricity purchase costs and electricity sales revenue are calculated based on tie-line interactive power variables, enhancing the accuracy and feasibility of the model; and the quantification of environmental pollution control costs promotes the environmental friendliness of the system by calculating pollutant emissions. 3. This invention optimizes the design of a constraint system that includes the balance of electric / thermal energy supply and demand, gravity energy storage operation constraints, power interaction constraints between the system and the main grid, controllable unit output and ramping constraints, battery operation constraints, and network operation constraints. This ensures the feasibility and safety of the scheduling scheme. By comprehensively covering physical and operational limitations, it enhances the stability of the system under complex operating conditions and avoids the occurrence of insufficient reliability due to ignoring actual constraints. Attached Figure Description

[0017] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings: Figure 1 This is a flowchart from Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the bidirectional control principle of the GES device in Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the computational structure in Embodiment 1 of the present invention; Figure 4 This is a schematic diagram of the wind, solar, and load prediction curves for a typical winter day in Embodiment 1 of the present invention; Figure 5 This is a schematic diagram of the power supply scheduling results on a typical winter day in Embodiment 1 of the present invention; Figure 6 This is a schematic diagram of the power supply scheduling results of the GES participating in the multi-energy complementary optimization operation of the system in Embodiment 1 of the present invention. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0019] Example 1: A regional integrated energy system dispatching method considering the participation of gravity energy storage, such as... Figure 1 As shown, it includes the following steps: S1: Configure gravity energy storage devices in the regional integrated energy system, and establish a dynamic coupling scheduling model between gravity energy storage, wind power and load based on the low storage and high generation characteristics of gravity energy storage devices. S2: Through a dynamic coupling scheduling model, the gravity energy storage device is controlled to store energy during the nighttime wind power surplus period to respond to the wind curtailment power, and the gravity energy storage device is controlled to release energy during the peak electricity load period to adjust the power supply gap, thereby realizing the two-way regulation of wind curtailment power and power supply gap. S3: With minimizing the system cycle operating cost as the objective function, construct an optimal scheduling model containing gravity energy storage devices, and use an optimization solver to solve the optimal scheduling model, outputting the optimal operating parameters of each device within the scheduling cycle.

[0020] Gravity energy storage (GES) utilizes energy storage media such as composite bricks or cement blocks, along with a reversible motor, to store and release energy by controlling the rise or fall of the energy storage media at different times.

[0021] In principle, GES is similar to existing pumped hydro storage technology, with one pumping water and the other pumping energy storage blocks. However, pumped hydro storage has a long construction cycle, high requirements for geographical conditions, and is not suitable for widespread deployment. Furthermore, its initial investment cost is higher, making it less economically viable. Compared to electrochemical energy storage, GES has advantages such as a longer lifespan, cleaner and more environmentally friendly operation, and safer and more stable energy storage. In the current context of green energy transition, GES has greater value for widespread application.

[0022] The GES physics model in this invention is designed as follows: ; ; ; ; In the formula, , The gravity energy storage power and energy storage efficiency of the GES device during time period t are respectively measured. , The gravity-driven energy release power and energy release efficiency of the GES device during time period t are respectively: Here, g is the mass of the GES device; g is the acceleration due to gravity. , The height changes during the energy storage and energy release phases of the GES device, respectively, are shown in time interval t. , These represent the energy stored in the GES device during time period t.

[0023] The principle of GES wind curtailment power response and power supply gap regulation is as follows: Figure 2 As shown. During periods of surplus wind power at night, the reversible motor switches to motor operation mode, using the surplus wind power to drive the motor and raise the energy storage medium to a high level to store gravitational potential energy; during peak system power load, the reversible motor switches to generator operation mode, driving the energy storage medium to descend to drive the generator to generate electricity, which is then delivered to users through the collector.

[0024] Economic efficiency is a crucial characteristic for the sustainable and robust development of RIES (Reinforced Energy Systems). This invention utilizes GES (Geometric Energy System) to bidirectionally regulate the system's wind curtailment and power supply gap, coupling CCHP (Cyclic Conversion Power), wind, solar, and battery systems for coordinated and complementary operation. This aims to reduce RIES operating costs during the dispatch cycle and promote wind power grid integration and consumption. This invention employs day-ahead dispatching with a dispatch cycle of T=24h. The objective function is expressed as: ; In the formula, The total system expenditure during time period t; , , , These include, respectively, the gas consumption expenditure of CCHP units during time period t, the total operating and maintenance expenditure of various unit equipment, the environmental treatment expenditure caused by the pollution discharged during the operation of the units, and the wind curtailment penalty fee levied on the system for wind curtailment; , These represent the electricity purchase costs incurred by the system in purchasing electricity from the main grid through the tie line and the electricity sales revenue generated by the system in selling electricity to the main grid during time period t. The investment and construction costs for the GES device are converted to the nearest day.

[0025] Gas consumption cost: As the core component of a multi-energy complementary RIES, the CCHP (Continuous Gas-fired Power Plant) undertakes the task of supplying energy to multiple loads, including electricity, heat, and cooling, within the system. Its gas consumption cost is: ; In the formula, The power generation capacity of the gas turbine during time period t; For gas turbine power generation efficiency; , These are the unit price of natural gas and the lower calorific value of natural gas, respectively.

[0026] Unit operation and maintenance costs: The units participating in RIES multi-energy complementary operation include CCHP, wind turbines, photovoltaics, GES, and batteries. The system unit operation and maintenance costs are: ; In the formula, , These represent the power generation of wind turbines and photovoltaic units during time period t, respectively. , These represent the storage and discharge power of the GES device and the battery pack during time period t, respectively. , , , , These are the unit power operation and maintenance costs for wind turbines, photovoltaic systems, gas turbines, GES (Geometric Energy Systems), and battery packs, respectively.

[0027] Environmental pollution control costs: Gas turbines produce pollutants such as SO2, CO2, and NOx during operation, and the system purchases most of its electricity from thermal power units during peak electricity consumption periods. Therefore, the system's environmental pollution control costs are expressed as follows: ; In the formula, , These represent the emissions of the i-th pollutant from the gas turbine and the power purchased from the main grid by the system during time period t. Let be the unit treatment cost for the i-th pollutant; j be the type of pollutant.

[0028] Wind curtailment penalty cost: To promote the grid connection and consumption of renewable energy, a penalty fee is levied on wind curtailment in the system, expressed as: ; In the formula, The system's wind curtailment power during time period t; The penalty fee for wind curtailment per unit of the system.

[0029] Electricity purchase cost: During peak electricity demand periods, the system's power supply capacity is limited, requiring it to purchase electricity from the main grid to meet user energy needs. The electricity purchase cost is expressed as follows: ; In the formula, The power purchased by the system from the main grid during time period t; The electricity price that the system purchases from the main grid.

[0030] Electricity sales revenue: During periods of surplus power in the system, revenue can be generated by selling electricity to the main grid through tie lines. Electricity sales revenue is expressed as: ; In the formula, The power sold by the system to the main grid through the tie line during time period t; The electricity price sold by the system to the main grid.

[0031] GES Investment and Construction Costs: As a newly introduced energy storage device in the system, the investment and construction costs of GES need to be considered to verify whether the system's operational efficiency is improved. The daily investment and construction cost of GES is: ; In the formula, The discount rate is... For the life cycle of the GES device; , These represent the planned capacity of the GES device and the construction cost per unit capacity, respectively.

[0032] The constraints of the optimized scheduling model include electrical energy supply and demand balance constraints, thermal energy supply and demand balance constraints, gravity energy storage device operation constraints, system-grid interaction power constraints, controllable unit output operation constraints, controllable unit ramp-up operation constraints, battery operation constraints, and network operation constraints.

[0033] The specific constraints on the supply and demand balance of electrical and thermal energy are as follows: ; ; In the formula, , These represent the system's electrical load and heat load during time period t, respectively. The heating power provided by CCHP after the waste heat from the gas turbine power generation during time period t is the heating power provided by CCHP.

[0034] The specific constraints on the output operation of controllable generating units are as follows: ; In the formula, , These are the lower and upper limits of the gas turbine output, respectively.

[0035] The specific constraints for the ramp-up operation of controllable units are as follows: ; In the formula: , These are the lower limit and upper limit of the ramp power of the gas turbine, respectively.

[0036] The specific power constraints for interaction between the system and the main network are as follows: ; ; In the formula, , These represent the upper limits of power purchase and power sales between the system and the main grid during time period t, respectively.

[0037] The specific constraints for GES operation are as follows: ; ; ; ; In the formula, , These are the lower and upper limits of the energy storage capacity of the GES device, respectively. , These represent the maximum changes in the moving height of the GES device during the energy storage and energy release phases, respectively.

[0038] The specific operating constraints of the battery are as follows: ; ; ; In the formula, Battery capacity; , These are the lower and upper limits of the battery's state of charge, respectively. , These are the lower and upper limits of battery output, respectively.

[0039] The specific network operation constraints are as follows: ; ; ; In the formula, The susceptance between nodes k and l; , These are the voltage phase angles at nodes k and l during time period t, respectively. This is the lower limit of the transmission power between nodes k and l; The natural gas flow rate between node p and node q during time period t; To comprehensively set parameters; , These are the air pressure values ​​at nodes p and q, respectively. , These are the air pressure values ​​at node p and node q during time period t, respectively. The gas pressure at node z in time period t; , These represent the upper and lower limits of the gas pressure in the pipeline at node z, respectively.

[0040] By solving for the energy storage and release power of GES and battery packs, the power output of gas turbines, and the interactive power of tie lines in each time period, the optimal operating parameters of each device in different time periods can be obtained, and then the day-ahead RIES scheduling scheme can be determined.

[0041] Since there are nonlinear constraints in the network operation constraints, they are transformed into linear constraints after piecewise linearization and solved in the commercial optimization software CPLEX, such as version CPLEX12.10.

[0042] This example uses a green energy demonstration project in North China as an example. The calculation structure is as follows: Figure 3 As shown. The system's typical winter day wind, solar, and load forecast curves are as follows. Figure 4 As shown in Table 1, the main parameters of the unit are as follows.

[0043] Table 2 Main parameters of the unit

[0044] To verify the advantages of GES participating in RIES multi-energy complementary operation, two simulation scenarios were used for verification and analysis. Scenario 1: Wind-Solar-CCHP-Battery Pack Multi-Energy Complementary Operation; Scenario 2: Wind-Solar-CCHP-GES-Battery Pack Multi-Energy Complementary Operation.

[0045] Scenario 1: Typical daily power supply dispatch results in winter. Figure 5 As shown. The system heat load during the scheduling cycle is provided by CCHP.

[0046] During the off-peak electricity price periods from January 1st to 6th and from January 23rd to 24th, the system experiences higher heat load demand. The CCHP's "heat-driven power generation" operation mode requires gas turbines to maintain high power output. Furthermore, wind power generation is high during this period due to its "anti-peak shaving" characteristics. Surplus electricity is sold to the main grid via interconnect lines, and batteries store energy during this time to prepare for potential power shortages. However, during these periods, interconnect lines reach their 200kW transmission capacity limit, and battery banks reach their 300 kWh storage capacity limit, resulting in some wind power being unable to be absorbed. Therefore, wind curtailment occurs during these periods.

[0047] During the period of grid parity from July 7th to 16th, the power load within the system is mainly met by wind power, photovoltaic power, and CCHP. Due to the relatively small heat load demand of the system during the period from July 13th to 16th, the power generation capacity of gas turbines is limited because they operate on a "heat-driven power generation" basis. As a result, the power supply units within the system cannot meet the power demand of users, and the power supply shortfall is made up by the system purchasing electricity from the main grid.

[0048] During the peak electricity price period from 17:00 to 22:00, due to high user electricity demand, the power supply units in the system are insufficient and the system purchase price of electricity is high. At this time, the battery pack releases energy to reduce the power purchased by the system from the main grid; the remaining power supply deficit is provided by the main grid.

[0049] The results of GES's participation in the system's multi-energy complementary optimized operation and power dispatching are as follows: Figure 6 As shown.

[0050] During the low electricity price periods of 1-6 and 23-24, the system's wind curtailment is concentrated during these periods due to limitations in power transmission channels and battery capacity. GES utilizes this curtailed wind power for gravity storage, thereby absorbing the curtailed wind power during these periods.

[0051] During the 7-16 electricity parity period, the system's electricity load is met by wind, solar, CCHP and the system's purchased power. During the 7 period, there is some wind curtailment, and GES uses gravity storage to absorb this curtailed wind power.

[0052] During the peak electricity price period from 17 to 22, the power supply units in the system cannot meet the electricity demand of users, and the system's electricity purchase cost is relatively high during this period. The GES releases energy to drive the generator to generate electricity, which is combined with the battery pack to supply power, thereby reducing the power purchased by the system from the main grid, reducing the system's electricity purchase cost and alleviating the peak-shaving pressure on the main grid during this period.

[0053] During the dispatch cycle, GES and battery banks formed a "capacity complementarity and fast-slow coordination" operation mode. During the peak wind power period at night, GES and battery banks worked together to continuously store energy, thereby smoothing wind power fluctuations and enabling full grid connection and absorption of wind power. During the peak electricity load period from 19:00 to 21:00, GES provided constant power supply, while battery banks only responded quickly to load gaps from 17:00 to 19:00, thereby accurately filling load peaks, avoiding power supply interruptions, and achieving a smooth transition between power supply and demand during peak load periods.

[0054] The system operating costs for each scenario are shown in Table 2. Analysis shows that GES can effectively utilize the system's curtailed wind power for gravity storage. Scenario 2 reduces the wind curtailment penalty cost by 100% compared to Scenario 1, achieving full wind power absorption. Furthermore, GES releases energy during peak load periods, thereby increasing the system's power supply capacity. The system's electricity purchase cost in Scenario 2 is 28.13% lower than in Scenario 1. After GES participates in the RIES multi-energy complementary optimization operation, the total cost of Scenario 1 is reduced by 3.71% and the environmental cost by 4.82% within the scheduling cycle, thus verifying the economic and environmental value of GES.

[0055] Table 3 System operating costs for various scenarios (RMB / day)

[0056] To address the wind curtailment issue caused by the "heat-driven power generation" operation mode of RIES during winter CCHP, a GES (Geoelectric Energy Storage) device was introduced to participate in the system's multi-energy complementary electrothermal optimization operation. Simulation verification was conducted using a green energy demonstration project as the research object: the GES effectively improves the system's wind power absorption capacity and power supply regulation capacity by absorbing the system's curtailed wind power through gravity storage and releasing energy for power generation during peak load periods. During the dispatch period, the system's wind curtailment penalty cost was reduced by 100%, and the total cost was reduced by 3.71%, achieving full absorption of renewable energy while also providing certain economic benefits. Furthermore, the GES can reduce the system's dependence on the main grid during peak load periods, thereby indirectly reducing the output of high-polluting units such as thermal power plants. During the dispatch period, the system's environmental cost was reduced by 4.82%, indicating that the GES's participation in optimized dispatch has significant social and environmental value.

[0057] Example 2: A regional integrated energy system dispatching system considering gravity energy storage, including gravity energy storage devices, wind power generation equipment, load equipment, gas turbines, battery banks, tie lines connected to the main grid, and control devices.

[0058] The control device is configured as follows: Based on the low storage and high generation characteristics of gravity energy storage devices, a dynamic coupling scheduling model is established between gravity energy storage, wind power, and load; through the dynamic coupling scheduling model, the gravity energy storage device is controlled to store energy during the nighttime wind power surplus period to respond to wind curtailment, and the gravity energy storage device is controlled to release energy during the peak electricity load period to adjust the power supply gap, thereby realizing bidirectional regulation of wind curtailment and power supply gap; with minimizing the system cycle operating cost as the objective function, an optimized scheduling model containing gravity energy storage devices is constructed, and an optimization solver is used to solve the optimized scheduling model, outputting the optimal operating parameters of each device within the scheduling cycle, wherein the device includes gas turbines, battery banks, and tie lines.

[0059] Working principle: This invention introduces a gravity energy storage device and establishes a dynamic coupled scheduling model to achieve bidirectional regulation of wind curtailment and power supply gap. During nighttime periods of surplus wind power, gravity energy storage responds to wind curtailment, effectively reducing wind power waste. During peak electricity load periods, gravity energy storage releases energy to regulate the power supply gap, reducing the system's dependence on the main grid. This not only improves the utilization rate of renewable energy and achieves full wind power consumption, but also reduces the total operating cost through optimized scheduling, making up for the shortcomings of existing technologies such as geographical limitations on the source side, poor implementation effect on the load side, and insufficient economic efficiency on the storage side.

[0060] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0061] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1A device that provides the functions specified in one or more boxes.

[0062] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0063] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0064] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A regional integrated energy system dispatching method considering the participation of gravity energy storage, characterized in that, Includes the following steps: By configuring gravity energy storage devices in a regional integrated energy system, and based on the low storage and high generation characteristics of the gravity energy storage devices, a dynamic coupling scheduling model between gravity energy storage, wind power and load is established. Through the dynamic coupling scheduling model, the gravity energy storage device is controlled to store energy during the nighttime wind power surplus period to respond to wind curtailment, and the gravity energy storage device is controlled to release energy during the peak electricity load period to adjust the power supply gap, thereby realizing bidirectional regulation of wind curtailment and power supply gap. With minimizing the system cycle operating cost as the objective function, an optimized scheduling model incorporating the gravity energy storage device is constructed. An optimization solver is then used to solve the optimized scheduling model, outputting the optimal operating parameters of each device within the scheduling cycle.

2. The regional integrated energy system dispatching method considering gravity energy storage participation according to claim 1, characterized in that, The cost components in the objective function include gas consumption costs, unit operation and maintenance costs, environmental pollution control costs, wind curtailment penalty costs, electricity purchase costs, electricity sales revenue, and the daily investment and construction costs of the gravity energy storage device. The objective function is expressed as minimizing the algebraic sum of all cost components; The electricity purchase cost and the electricity sales revenue are calculated through the power exchange between the system and the main grid via the tie line.

3. The regional integrated energy system dispatching method considering gravity energy storage participation according to claim 2, characterized in that, The electricity purchase cost and the electricity sales revenue are calculated through power exchange via the tie line between the system and the main grid, including: The electricity purchase cost is calculated based on the electricity purchase power variable in the interconnection power of the tie line; The electricity sales revenue is calculated based on the electricity sales power variable in the interconnection power of the tie line. The power purchase power variable and the power sales power variable are decision variables in the optimized scheduling model, and are determined by solving the model.

4. The regional integrated energy system dispatching method considering gravity energy storage participation according to claim 2, characterized in that, The calculation of the environmental pollution control cost includes: Calculate the emissions of sulfur dioxide, carbon dioxide, and nitrogen oxides based on the power generated by the gas turbine and the power purchased from the main grid. The environmental pollution control cost is obtained by multiplying the emission amount of each pollutant by the corresponding unit treatment cost and then summing the results.

5. The regional integrated energy system dispatching method considering gravity energy storage participation according to claim 1, characterized in that, The constraints of the optimized scheduling model include: The power supply and demand balance constraint is configured such that the sum of power generation, energy storage, and interconnection power equals the power load. The thermal energy supply and demand balance constraint requires that the heating power be equal to the heat load power. The operational constraints of the gravity energy storage device are configured to include upper and lower limits of energy storage, height variation constraints during energy storage and release phases, and energy storage equalness constraints at the beginning and end of the scheduling cycle. The system interacts with the main grid to constrain power consumption, and is configured to limit the power purchased and sold to a preset upper limit.

6. The regional integrated energy system dispatching method considering gravity energy storage participation according to claim 5, characterized in that, The constraints of the optimized scheduling model also include: The controllable unit output operation constraints are configured as upper and lower limit constraints for gas turbine output. The controllable unit ramp-up operation constraint is configured as the gas turbine ramp-up power limit; Battery operation constraints are configured as state of charge constraints, output constraints, and equal charge level throughout the cycle. Network operation constraints are configured as power network flow constraints and natural gas network flow constraints.

7. The regional integrated energy system dispatching method considering gravity energy storage participation according to claim 1, characterized in that, The physical model configuration of the gravity energy storage device is as follows: The energy storage power of the gravity energy storage device is equal to its energy storage efficiency multiplied by its mass, gravitational acceleration, and the change in height during the energy storage stage. The energy release power of the gravity energy storage device is equal to its energy release efficiency multiplied by the change in energy storage during the energy release stage. The change in altitude is limited by the maximum change value during the energy storage and energy release phases, respectively.

8. The regional integrated energy system dispatching method considering gravity energy storage participation according to claim 1, characterized in that, The method also includes: This enables the gravity energy storage device and the battery pack to operate in a complementary capacity and coordinated fast and slow operation mode; During peak wind power periods at night, the gravity energy storage device and the battery pack work together to perform energy storage operations, so as to smooth wind power fluctuations and promote full wind power consumption. During peak electricity load periods, the gravity energy storage device releases energy at a constant power, while the battery pack responds quickly to fill the load gap.

9. The regional integrated energy system dispatching method considering gravity energy storage participation according to claim 1, characterized in that, The optimization solver is CPLEX software; Specifically, the nonlinear constraints in the optimized scheduling model are transformed into linear constraints by performing piecewise linearization, and then solved using the CPLEX software.

10. A regional integrated energy system dispatching system considering the participation of gravity energy storage, characterized in that, This includes gravity energy storage devices, wind power generation equipment, load equipment, gas turbines, battery packs, tie lines connecting to the main grid, and control devices; The control device is configured to: Based on the low storage and high generation characteristics of the gravity energy storage device, a dynamic coupling scheduling model between gravity energy storage, wind power and load is established. Through the dynamic coupling scheduling model, the gravity energy storage device is controlled to store energy during the nighttime wind power surplus period to respond to wind curtailment, and the gravity energy storage device is controlled to release energy during the peak electricity load period to adjust the power supply gap, thereby realizing bidirectional regulation of wind curtailment and power supply gap. With minimizing the system cycle operating cost as the objective function, an optimized scheduling model including the gravity energy storage device is constructed, and an optimization solver is used to solve the optimized scheduling model to output the optimal operating parameters of each device within the scheduling cycle, wherein the device includes the gas turbine, the battery pack and the tie line.

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