Ocean island group division method based on function positioning

Abstract

The invention relates to the technical field of island micro-grid planning, in particular to an ocean island group division method based on function positioning. Comprising the following steps: based on island power supply development conditions, electric energy delivery economy and power supply power generation cost, evaluating electric energy delivery potential to determine island positioning; calculating island micro-grid group division indexes; and dividing the ocean island group by adopting a multi-strategy fusion particle swarm algorithm by using the island micro-grid group division index. The method is suitable for a planning scene of ocean island groups, renewable energy sources of different islands can be fully integrated, the operation reliability and the new energy utilization rate of the whole system are improved, the power generation capacity and requirements of the islands are comprehensively considered, power resources are reasonably distributed to the island groups, the energy utilization efficiency of the system is improved, and the energy utilization rate of the system is increased. The problems that the variable dimension of the planning model is sharply increased due to the scale expansion of the island group, and the model becomes complex and is difficult to solve are solved, and meanwhile, the current situation that the renewable energy sources of the island group are unreasonably configured is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of island microgrid planning, and in particular relates to a method for dividing offshore island groups based on functional positioning. Background Art

[0002] Most of the islands in my country that currently have electricity supply are offshore islands connected to the large onshore power grid through submarine cables. Compared with offshore islands, offshore islands are far away from the land. Considering the cost of submarine cable construction and maintenance difficulties, it is not suitable to build a grid-connected offshore island microgrid. In order to get rid of the dependence of offshore island groups on fossil energy and achieve a balance between electricity supply and demand, it is urgent to build a new type of power supply system. By supplying power to resource islands and using electricity to load islands, a balance between supply and demand can be achieved in a local area to meet the electricity needs of island development and residents' lives. Reasonable determination of the function of each island in the island group energy supply system is the basis for the planning of island microgrid groups. At the same time, in order to address the problem of idleness and shortage of renewable energy in the island group due to unreasonable division of island groups, a suitable offshore island group division method is needed to divide the islands, but there is no reasonable division method in the prior art. Summary of the invention

[0003] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a method for dividing offshore island groups based on functional positioning.

[0004] The purpose of the present invention can be achieved by the following technical solutions:

[0005] The present invention provides a method for dividing offshore island groups based on functional positioning, comprising the following steps:

[0006] Step S1: Based on the data of each island, evaluate the power transmission potential of each island to determine the functional positioning of the island;

[0007] Step S2: Calculate the island microgrid group division index based on the functional positioning of each island in step S1;

[0008] Step S3: Divide the island groups according to the island microgrid group division index using the particle swarm algorithm with multi-strategy fusion to obtain the optimal island group division result.

[0009] Furthermore, the data of each island in step S1 include: the total annual wind and solar power generation of the island, the total annual load demand of the island, the average annual investment cost of new energy on the island, the annual operating cost of new energy on the island and the profit of electricity sales on the island.

[0010] Furthermore, the functional positioning of the island includes a load island and a resource island.

[0011] Furthermore, step S1 includes: solving the power transmission potential x1 after the island land conditions and the construction period, solving the power transmission potential x2 of the island power generation cost, solving the power transmission potential x3 of the island power transmission economy, and functionally positioning the island according to the three potentials x1, x2, and x3 corresponding to each island.

[0012] Furthermore, the step S1 specifically includes the following steps:

[0013] Step S1.1: Solve the island land conditions and the power transmission potential x1 after the construction period. The calculation formula is:

[0014]

[0015] in, is the total annual wind and solar power generation on the island; is the total annual demand of island load;

[0016] Step S1.2: Calculate the power transmission potential x2 of the island power generation cost, and the calculation formula is:

[0017] x2=p RES -p G

[0018] Among them, p RES is the cost of renewable energy power generation; p G Cost of electricity generation for diesel generators;

[0019] S1.3. Calculate the economical power transmission potential x3 of the island power transmission. The calculation formula is:

[0020]

[0021] in, is the average annual investment cost of new energy on islands; is the annual operating cost of new energy on the island; sale Profit from selling electricity to the islands;

[0022] Step S1.4: functionally locate the island according to its three potentials x1, x2, and x3;

[0023] Step S1.5: Repeat steps S1.1 to S1.4 until all islands have completed their functional positioning.

[0024] Furthermore, the step S1.4 specifically includes: determining whether x1, x2, and x3 calculated in the above steps are all greater than or equal to 0. If so, the island is a resource island; if one or more of them is less than 0, the island is a load island.

[0025] Furthermore, the step S2 specifically includes the following steps:

[0026] Step S2.1: Calculate the island group distance index ρ D , the calculation formula is:

[0027]

[0028] Among them, ρ D is the total distance index of the offshore island group; D rl is the distance between the load island and the resource island; Ω r,i is the set of all resource islands in island group i; Ω l,i is the set of all load islands in island group i; Ω l is the set of all load islands in the original island group, and m is the number of island groups;

[0029] Step S2.2: Calculate the island group energy balance index ρ E,i,t , the calculation formula is:

[0030]

[0031] E dem.total =E dem.e +E dem.h +E dem.w

[0032] E sup,total =E sup,PV +E sup,WT

[0033] Among them, ρ E,i,t is the energy balance index of the ith island group at time t; T is the scheduling period; ρ E It is the energy balance index of the entire island group; E sup,i,t The electrical energy provided to the i-th island group at time t; E dem,i,t+Δt is the electric energy required by the i-th island group at time t+Δt; Δt is the time delay of electric energy transmission; E dem.total is the total electrical energy required by the island group; E dem.e The electric energy required by the electrical load in the island group; E dem.h The electrical energy required for the hydrogen load in the island group; E dem.w The electrical energy required for the freshwater load of the islands; E sup,total Electricity provided to island groups for new energy units; E sup,PV Electricity provided by photovoltaic power plants within the island group; E sup,WT Power for wind turbines in the island group;

[0034] Step S2.3: Calculate the island group membership index, the calculation formula is:

[0035]

[0036] Among them, ρA is the island group membership index, F rl is the interaction force between the resource island and the load island.

[0037] Furthermore, the F rl The calculation formula is:

[0038]

[0039] in, is the total annual net load of the load island, is the total net power of the resource island in year j, D rl is the distance between the load island and the resource island

[0040] Furthermore, the step S3 specifically includes the following steps:

[0041] A multi-objective optimization model is established based on the three indicators, and they are weighted and combined to form a comprehensive island group division indicator F;

[0042] The objective function of the offshore island group division method is as follows:

[0043]

[0044]

[0045] Among them, F is the comprehensive classification index of offshore island groups; is the weight corresponding to each indicator;

[0046] The optimization model is a mixed integer programming model, which uses a particle swarm algorithm with multi-strategy fusion to solve the island group division according to the objective function to obtain the optimal island group division result.

[0047] Furthermore, the process of solving the island group division using the particle swarm algorithm with multi-strategy fusion also includes the following constraints: there is at least one load island and one resource island in the island group, and the time it takes for the energy storage ship to travel from the load island to the farthest resource island is less than half of the island group scheduling cycle.

[0048] Compared with the prior art, the present invention has the following advantages:

[0049] 1. The present invention determines the location of islands according to their transmission potential by comprehensively evaluating the conditions for power development on islands, the economics of power transmission and the cost of power generation. This can accurately match the resources and needs of each island and solve the problem of ambiguous functional positioning in offshore island groups.

[0050] 2. The present invention adopts the island group distance index, island group energy supply index and island group membership index to divide the offshore island groups, comprehensively considers the power generation capacity and demand of the islands, and rationally allocates power resources to each island group, thereby improving the energy utilization efficiency of the system, solving the problem that the expansion of the scale of the island group leads to a sharp increase in the variable dimension of the planning model, and the model becomes complex and difficult to solve. At the same time, it improves the current situation of unreasonable configuration of renewable energy in the island group. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 The numbers and relative positions of the islands in Example 2 are shown in FIG.

[0052] Figure 2 This is a result diagram of dividing the offshore island group using the island microgrid group division index after locating the island function in Example 2;

[0053] Figure 3 This is the wind speed distribution diagram of the offshore island group area in Example 2;

[0054] Figure 4 This is a diagram of the monthly average solar radiation in the offshore island group area of ​​Example 2. DETAILED DESCRIPTION

[0055] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0056] Embodiment 1:

[0057] The purpose of this embodiment is to provide a method for dividing offshore island groups based on functional positioning, so as to improve the utilization rate of new energy and power supply reliability of the whole system. This embodiment provides a method for dividing offshore island groups based on functional positioning, including the following steps:

[0058] S1. Based on the island power development conditions, power transmission economics and power generation costs, the power transmission potential is evaluated to determine the location of the island.

[0059] S2. Calculate the island microgrid group division indicators.

[0060] S3. Use the island microgrid group division indicators to divide the offshore island groups.

[0061] Further, the specific implementation steps of S1 are:

[0062] S1.1. Solve the island land conditions and the power transmission potential after the construction period x1. The specific steps are as follows:

[0063]

[0064] In the formula, is the total annual wind and solar power generation on the island; It is the total annual demand of island load.

[0065] S1.2. Calculate the power transmission potential x2 of the island power generation cost. The specific steps are as follows:

[0066] x2=p RES -p G

[0067] In the formula, p RES is the cost of renewable energy power generation; p G Cost of electricity generated by diesel generators.

[0068] S1.3. Calculate the economical power transmission potential x3 of the island power transmission. The specific steps are as follows:

[0069]

[0070] In the formula, is the average annual investment cost of new energy on islands; is the annual operating cost of new energy on the island; sale Profit from selling electricity on islands.

[0071] Further, the specific implementation steps of S2 are:

[0072] S2.1. Calculation of island group distance index ρ D , the distance from the resource island to the load island will directly affect the investment and operation cost of the island group energy supply system, and the calculation formula is as follows:

[0073]

[0074] Among them, ρ D is the total distance index of the offshore island group; D rl is the distance between the load island and the resource island; Ω r,i is the set of all resource islands in island group i; Ω l,i is the set of all load islands in island group i; Ω l is the set of all load islands in the original island group, and m is the number of island groups.

[0075] S2.2. Calculation of island group energy balance index ρ E,i,t Since the measurement units of electricity, hydrogen and fresh water are different, it is impossible to quantitatively describe the supply and demand relationship of energy in the island group. Therefore, the unit of electricity is used as the unified measurement unit of each energy source, ρ E,i,t The calculation formula is as follows:

[0076]

[0077] E dem.total =E dem.e +E dem.h +E dem.w

[0078] E sup,total =E sup,PV +E sup,WT

[0079] In the formula, ρ E,i,t is the energy balance index of the ith island group at time t; T is the scheduling period; ρ E It is the energy balance index of the entire island group; E sup,i,t The electrical energy provided to the i-th island group at time t; E dem,i,t+Δt is the electric energy required by the i-th island group at time t+Δt; Δt is the time delay of electric energy transmission; E dem.total is the total electrical energy required by the island group; E dem.e The electric energy required by the electrical load in the island group; E dem.h The electrical energy required for the hydrogen load in the island group; E dem.w The electrical energy required for the freshwater load of the islands; E sup,total Electricity provided to island groups for new energy units; E sup,PV Electricity provided by photovoltaic power plants within the island group; E sup,WT Provides electrical energy for wind turbines within the island group.

[0080] S2.3. Calculate the island group membership index. The specific steps are as follows:

[0081] S2.3.1. Derived from the traditional universal gravitation model, the calculation formula is as follows:

[0082]

[0083] In the formula, F is the magnitude of the universal gravitation between celestial bodies; k is the gravitational coefficient; m is the mass of the central celestial body; M is the mass of the planetary body; D is the distance between the celestial body and the planet; is the total annual net load of the load island; is the total net power of resource island j in year; ρ A is the island group membership index, F rl is the interaction force between the resource island and the load island.

[0084] S2.3.2. Calculation of island group membership index ρ A , the calculation formula is as follows:

[0085]

[0086] F rlThe calculation formula is:

[0087]

[0088]

[0089] in, is the total annual net load of the load island, is the total net power of the resource island in year j, D rl is the distance between the load island and the resource island

[0090] In the formula, ρ A is the island group membership index, F rl is the interaction force between the resource island and the load island.

[0091] Furthermore, the specific implementation steps of S3 are:

[0092] A multi-objective optimization model is established based on the three indicators, which are weighted and combined to form a comprehensive island group division indicator F.

[0093] The objective function of the offshore island group division method is as follows:

[0094]

[0095] Where, F is the comprehensive classification index of offshore island groups; is the weight corresponding to each indicator.

[0096] This optimization model is a mixed integer programming model, which is solved by a particle swarm algorithm with multi-strategy fusion. Based on the original particle swarm algorithm, the particle position and speed process are optimized to improve the optimization efficiency of the particle swarm optimization algorithm. The specific steps are as follows:

[0097] Step 1: Initialize parameters, including population size N, maximum number of iterations T max , various variables and parameter settings;

[0098] Step 2: Set the number of iterations to t = 1 and initialize the particle speed and location Arrange the fitness values ​​of particles in descending order, find the individual extreme values ​​of each particle and the global extreme value, and store them in the elite set;

[0099] Step 3: Update the inertia weight, and update the particle speed and position;

[0100] Step 4: Determine the fitness value of each particle according to the objective function, sort them, compare the quality of particles, update the individual extreme value of each particle and the global extreme value and store them in the elite set;

[0101] Step 5: Determine whether the set maximum number of iterations is met. If so, proceed to step 6, otherwise return to step 3;

[0102] Step 6: Select 50% of the best particles in the elite set, use the steepest descent method to find the optimal solution, and use the optimization results to update the elite set;

[0103] Step 7: Get the optimal solution.

[0104] In the process of island group division, the time delay of ships in island group transportation is taken into account and the following constraints are taken into account: 1) there is at least one load island and one resource island in the island group; 2) the time it takes for the energy storage ship to travel from the load island to the farthest resource island is less than half of the island group scheduling cycle.

[0105] Based on the island group distance index and the island group energy balance index, the preliminary division is carried out. In order to further solve the problem of island group affiliation, the island group affiliation index is used to further optimize the island group division and readjust the affiliation of the islands. This method sets a certain threshold. If the affiliation degree of an island ρ A If the degree of affiliation is higher than the threshold, it will belong to the island group. If the degree of affiliation is lower than the threshold, the island needs to reconsider its affiliation, recalculate the island group distance index and the island group energy balance index, and adjust it to the island group with which it has stronger interaction.

[0106] Embodiment 2:

[0107] The parts not mentioned in this embodiment are the same as those in Embodiment 1.

[0108] An island group in the southern waters of my country was selected as the research object. There are 9 islands in total, numbered 1 to 9. Among them, islands 1, 2, 3, and 7 are inhabited, and islands 4, 5, 6, 8, and 9 are undeveloped islands. The numbers and relative positions of each island are as follows: Figure 1 As shown in Figure 2, the wind speed distribution in the offshore island group area is as follows: Figure 3 As shown in Figure 2, the monthly average solar radiation in the offshore island group area is as follows: Figure 4 shown.

[0109] This example locates the functions of 9 islands and divides them into island groups. The wind turbine and photovoltaic parameters are shown in Tables 1 and 2.

[0110] Table 1 Fan related parameters

[0111]

[0112] Table 2 Photovoltaic related parameters

[0113]

[0114] S1: Calculate the exploitable amount of wind and solar resources on each island in a year. It should be noted that:

[0115] (1) Calculate the technically exploitable amount of island wind energy resources:

[0116] The development and utilization of wind energy resources are affected by geographical conditions, socio-economic conditions and other factors, and are subject to the following restrictions: the minimum distance between a wind farm and residential areas cannot be less than 2000m; the minimum distance between a wind farm and a protected area cannot be less than 1000m; the row spacing of wind turbines should not be less than 3 times the diameter of the impeller, and the column spacing should not be less than 5 times the diameter of the impeller; the regional slope should be less than 15°; the wind speed at 10m from the wind farm site should be greater than 5m / s, and the wind power density should be greater than 150W / m 2 .

[0117]

[0118] In the formula, is the fan power at that moment; is the rated power of the fan; v in is the cut-in wind speed; v out E is the wind speed cut-out wind speed; e is the annual total power generation; N W is the number of wind turbines on the island.

[0119] (2) Calculate the technically exploitable amount of solar energy resources on islands:

[0120] The exploitable amount of solar energy technology is subject to the following restrictions: the regional slope should be less than 15°; the average regional radiation is greater than 1050; distributed photovoltaics are installed on roofs and farmland, and centralized photovoltaics are installed on open space with no other use; photovoltaics are strictly prohibited in protected areas. The island photovoltaic resource assessment uses solar energy resource parameters such as light intensity, and considers land conditions, optimal tilt angle and other restrictions to calculate the exploitable amount of island solar energy resources technology. The optimal photovoltaic panel tilt angle is:

[0121] β=-0.0049φ 2 +1.0888φ

[0122] Where β is the optimal tilt angle of the photovoltaic panel; φ is the latitude.

[0123] Taking into account the influence of factors such as land area utilization rate and terrain slope, the technically exploitable amount of solar energy resources is:

[0124]

[0125] In the formula, R is the exploitable amount of solar energy technology; b(t) is the incident shortwave radiation flux at the optimal tilt angle in time period t; S is the total land area; ω is the area factor, which is taken as 0.7; α is the solar power installation reduction coefficient; η is the power generation efficiency of the photovoltaic module; Δt is the time interval. According to the technically installable capacity of wind and solar power generation devices on each island in the island group, as well as the annual wind speed and light intensity data, the annual technical exploitable amount of wind and solar resources on each island can be calculated as shown in Table 3.

[0126] Table 3 Annual exploitable amount of wind and solar resources on each island

[0127]

[0128] S2. Evaluate the power transmission potential of each island to determine the location of the island. It should be noted that:

[0129] Islands 4, 5, 6, 8 and 9 have great potential for wind and solar development and are uninhabited, so it is assumed that their total annual load is zero. Table 4 shows the annual load and total renewable energy power generation of each island.

[0130] Table 4 Annual load of islands and total amount of renewable energy power generation

[0131]

[0132] The annual load demand of islands 1, 2, and 3 is much greater than the annual technical exploitable amount of wind and solar resources, and their x1 is less than 0, and F is less than 0. Therefore, islands 1, 2, and 3 are positioned as load islands. The annual technical exploitable amount of wind and solar resources of the remaining islands is greater than the annual load demand. Taking island 7 as an example, it is precisely divided, and the calculation results under various setting conditions are shown in Table 5.

[0133] Table 5 Calculation results of various setting conditions of island 7

[0134]

[0135] From the above table, we can see that the difference of each setting condition of island 7 is greater than zero, indicating that island 7 has great potential for power transmission, so island 7 is positioned as a resource island. Similarly, we can see that islands 4, 5, 6, 8, and 9 are all resource islands.

[0136] S3. Based on the functional positioning of each island, the three island group division indicators are calculated and the final results are obtained. It should be noted that:

[0137] In the process of island group division, the time delay of ships in island group transportation is taken into account and the following constraints are taken into account: 1) there is at least one load island and one resource island in the island group; 2) the time it takes for the energy storage ship to travel from the load island to the farthest resource island is less than half of the island group scheduling cycle.

[0138] This method uses a particle swarm algorithm with multi-strategy fusion to solve. The calculation results show that when only the island group distance index and the island group energy balance index are considered, there are three island groups in total, of which islands 1, 4, and 5 belong to island group 1, islands 2, 6, 7, and 9 belong to island group 2, and islands 3, 7, and 8 belong to island group 3. The island group division results will result in resource islands belonging to two island groups. Set the threshold of the island group membership index to 0.8, recalculate the island membership, and the calculation results show that island 7 belongs to island group 2. The final island group division results are as follows: Figure 2 Therefore, the present invention can obtain the classification of offshore island groups under the island function positioning.

[0139] If the above functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program code.

[0140] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A method for dividing offshore island groups based on functional positioning, characterized in that: The following steps are involved: Step S1: Based on the data of each island, evaluate the power transmission potential of each island to determine the functional positioning of the island; Step S2: Calculate the island microgrid group division index based on the functional positioning of each island in step S1; Step S3: Divide the island groups according to the island microgrid group division index using the particle swarm algorithm with multi-strategy fusion to obtain the optimal island group division result.

2. The method for dividing offshore island groups based on functional positioning according to claim 1 is characterized in that: The data of each island in step S1 include: the total annual wind and solar power generation of the island, the total annual load demand of the island, the average annual investment cost of new energy on the island, the annual operating cost of new energy on the island and the profit of electricity sales on the island.

3. The method for dividing offshore island groups based on functional positioning according to claim 1 is characterized in that: The functional positioning of the island includes load island and resource island.

4. The method for dividing offshore island groups based on functional positioning according to claim 1 is characterized in that: The step S1 includes: solving the power transmission potential x1 after the island land conditions and the construction period, solving the power transmission potential x2 of the island power generation cost, solving the power transmission potential x3 of the island power transmission economy, and functionally positioning the island according to the three potentials x1, x2, and x3 corresponding to each island.

5. The method for dividing offshore island groups based on functional positioning according to claim 4 is characterized in that: The step S1 specifically includes the following steps: Step S1.1: Solve the island land conditions and the power transmission potential x1 after the construction period. The calculation formula is: in, is the total annual wind and solar power generation on the island; is the total annual demand of island load; Step S1.2: Calculate the power transmission potential x2 of the island power generation cost, and the calculation formula is: x2=p RES -p G Among them, p RES is the cost of renewable energy power generation; p G Cost of electricity generation for diesel generators; S1.

3. Calculate the economical power transmission potential x3 of island power transmission. The calculation formula is: in, is the average annual investment cost of new energy on islands; is the annual operating cost of new energy on the island; sale Profit from selling electricity to the islands; Step S1.4: functionally locate the island according to its three potentials x1, x2, and x3; Step S1.5: Repeat steps S1.1 to S1.4 until all islands have completed their functional positioning.

6. The method for dividing offshore island groups based on functional positioning according to claim 5 is characterized in that: The step S1.4 specifically includes: determining whether x1, x2, and x3 calculated in the above steps are all greater than or equal to 0. If so, the island is a resource island; if one or more of them is less than 0, the island is a load island.

7. The method for dividing offshore island groups based on functional positioning according to claim 1 is characterized in that: The step S2 specifically includes the following steps: Step S2.1: Calculate the island group distance index ρ D , the calculation formula is: Among them, ρ D is the total distance index of the offshore island group; D rl is the distance between the load island and the resource island; Ω r,i is the set of all resource islands in island group i; Ω l,i is the set of all load islands in island group i; Ω l is the set of all load islands in the original island group, and m is the number of island groups; Step S2.2: Calculate the island group energy balance index ρ E,i,t , the calculation formula is: AND dem.total =And dem.e +E dem.h +E dem.w AND sup,total =And sup,PV +E sup,WT Among them, ρ E,i,t is the energy balance index of the ith island group at time t; T is the scheduling period; ρ E It is the energy balance index of the entire island group; E sup,i,t The electrical energy provided to the i-th island group at time t; E dem,i,t+Δt is the electric energy required by the i-th island group at time t+Δt; Δt is the time delay of electric energy transmission; E dem.total is the total electrical energy required by the island group; E dem.e The electric energy required by the electrical load in the island group; E dem.h The electrical energy required for the hydrogen load in the island group; E dem.w The electrical energy required for the freshwater load of the islands; E sup,total Electricity provided to island groups for new energy units; E sup,PV Electricity provided by photovoltaic power plants within the island group; E sup,WT Power for wind turbines in the island group; Step S2.3: Calculate the island group membership index, the calculation formula is: Among them, ρ A is the island group membership index, F rl is the interaction force between the resource island and the load island.

8. The method for dividing offshore island groups based on functional positioning according to claim 7 is characterized in that: The F rl The calculation formula is: in, is the total annual net load of the load island, is the total net power of the resource island in year j, D rl is the distance between the load island and the resource island.

9. A method for dividing offshore island groups based on functional positioning according to claim 1 or 7, characterized in that: The step S3 specifically comprises the following steps: A multi-objective optimization model is established based on the three indicators, and they are weighted and combined to form a comprehensive island group division indicator F; The objective function of the offshore island group division method is as follows: Among them, F is the comprehensive classification index of offshore island groups; is the weight corresponding to each indicator; The optimization model is a mixed integer programming model, which uses a multi-strategy fusion particle swarm algorithm to solve the island group division according to the objective function to obtain the optimal island group division result.

10. The method for dividing offshore island groups based on functional positioning according to claim 9, characterized in that: The process of solving the island group division using the multi-strategy fusion particle swarm algorithm also includes the following constraints: there is at least one load island and one resource island in the island group, and the time it takes for the energy storage ship to travel from the load island to the farthest resource island is less than half of the island group scheduling cycle.

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