Grid-connected green electricity direct connection project source and load storage collaborative planning method and system

Abstract

The application discloses a grid-connected green electricity direct connection project source-load-storage collaborative planning method and system, the planning boundary of the power supply, the load, the energy storage, the direct connection line and the public grid access point is determined through the method and system, the grid-connected and direct connection dual-channel energy supply model is established, the access capacity and the load bearing capacity are analyzed, the collaborative planning model taking the new energy capacity, the energy storage scale, the line capacity, the access capacity and the construction time sequence as variables is constructed, the staged expansion and the operation scene safety checking mechanism are introduced, and the comprehensive planning scheme and the engineering implementation list are output; the scheme can coordinate the relationship between the direct connection power supply and the public grid connection, improve the green electricity replacement rate, the power supply reliability and the planning implementability.

Description

Technical Field

[0001] This invention relates to the fields of power grid dispatching technology and power grid management technology, and in particular to a method and system for source-load-storage coordinated planning of grid-connected green energy direct connection projects. Background Technology

[0002] With the increasing demand for renewable energy, green electricity substitution, and low-carbon energy from large users, industrial parks, ports, integrated energy bases, and large manufacturing enterprises are gradually adopting direct green electricity connections, supplying renewable energy sources such as wind and solar power directly to user loads via dedicated lines. At the same time, to ensure power supply continuity and project operational safety, these projects typically still need to maintain grid connection with the public power grid, forming a composite energy supply system that possesses both direct green electricity connection and public power grid connection attributes.

[0003] Existing planning methods for green energy direct connection projects typically focus on one aspect of renewable energy power plant construction scale, dedicated power supply line routes, or user-side electricity demand, rarely considering direct power supply channels, public grid access channels, energy storage regulation capacity, and load growth characteristics simultaneously within the same planning framework. Because the functional boundaries between direct connection links and grid-connected links are unclear, it is easy to make it difficult to accurately distinguish the electricity relationships between local green energy consumption, grid supplementary power supply, energy storage regulation, and surplus electricity fed into the grid during the planning stage, thus affecting the accuracy of project green energy substitution rates, grid access capacity configuration, and engineering investment calculations.

[0004] Furthermore, existing planning methods often lack a linkage analysis between public grid access capacity and the internal source-load-storage configuration of projects. Some schemes determine grid access capacity solely based on the user's maximum load, failing to fully consider factors such as renewable energy output fluctuations, energy storage charging and discharging behavior, surplus power backflow capability, short-circuit capacity, voltage fluctuation tolerance, and protection coordination requirements. This can easily lead to a mismatch between the source-side installed capacity and the public grid access conditions. Other schemes configure energy storage only from the perspective of renewable energy consumption, without combining the analysis of energy storage placement location, direct connection line capacity level, and critical load power supply reliability requirements. This results in energy storage configurations being too large or too small, or providing insufficient operational support.

[0005] Meanwhile, grid-connected green energy direct-connection projects are generally characterized by phased construction, annual load growth, gradual development of new energy resources, and dynamic changes in grid connection policies. Traditional one-time planning methods struggle to balance short-term investment economics with long-term expansion needs, easily leading to problems such as over-construction in the early stages, limited expansion in the later stages, insufficient reserved grid connection capacity, or uncoordinated surplus power grid connection capacity. For typical operating scenarios such as high output and low load, low output and high load, public grid failures, direct-connection line failures, energy storage withdrawal from operation, and maintenance switching, existing solutions often lack systematic simulation verification, resulting in insufficient safety and feasibility of the planning results in actual engineering operation.

[0006] Therefore, it is necessary to propose a source-load-storage coordinated planning method and system for grid-connected green energy direct connection projects. Based on clarifying the project planning boundaries, this method unifies the modeling of direct power supply channels and public grid connection channels, and comprehensively considers power source construction, load demand, energy storage configuration, direct connection line capacity, public grid access capacity, surplus power grid connection capacity, and phased construction sequence. This will solve the problems of unclear planning boundaries, difficulty in coordinating the relationship between direct connection and grid connection, mismatch between access capacity and source-load-storage scale, and / or lack of overall planning of construction sequence in grid-connected green energy direct connection projects. Summary of the Invention

[0007] In view of this, the purpose of this invention is to propose a source-load-storage collaborative planning method and system for grid-connected green electricity direct connection projects.

[0008] To achieve the above-mentioned technical objectives, the technical solution adopted by this invention is as follows: A source-load-storage coordinated planning method for grid-connected green energy direct-connection projects, comprising: S1. Obtain basic planning data for grid-connected green electricity direct connection projects; determine the project planning boundary based on the basic planning data, and construct the planning object topology based on the project planning boundary; S2. Based on the topology of the planned object, establish a dual-channel energy supply model of grid connection and direct connection, and establish energy supply coordination rules between direct connection channel and grid connection channel according to the operation sequence of priority supply of green electricity to local load, participation of energy storage in differential regulation, supplementary power supply of public grid and grid connection of surplus green electricity. S3. Based on the grid-connected and direct-connected dual-channel power supply model, analyze the access capacity and load carrying capacity of the public power grid access point and the internal power supply network of the project to obtain the access capacity and load carrying capacity boundary information. S4. Construct a source-load-storage collaborative planning model using preset decision variables; the source-load-storage collaborative planning model takes project investment and operating costs, green electricity substitution rate, power supply reliability, grid impact degree and / or planning expansion capacity as planning evaluation targets, and sets constraints in combination with access capacity and load carrying capacity boundary information; S5. Based on the source-load-storage collaborative planning model, establish a phased construction and rolling expansion mechanism, divide the planning cycle into multiple construction phases, and determine the adjustment scheme according to the preset conditions in each construction phase to obtain a phased planning scheme. S6. Perform operational scenario simulation and safety verification on the phased planning scheme formed in step S5. Perform verification under the operational scenario and correct the decision variables in the source-load-storage collaborative planning model according to the verification results. S7. Based on the planning results after safety verification, output the comprehensive planning scheme and engineering implementation list for grid-connected green electricity direct connection projects.

[0009] As a preferred implementation method, preferably, in step S1 of this scheme, the basic planning data includes one or more of the following: new energy resource data, user load data, energy storage deployment conditions, direct connection line conditions, public power grid access point data, and project construction timeline data.

[0010] The project planning boundary includes one or more of the following: power supply side objects, direct connection line objects, user load objects, energy storage objects, and public grid access point objects.

[0011] In step S1, the topology of the planning object is represented by a set of nodes and a set of connecting edges. The set of nodes includes new energy power nodes, load nodes, energy storage nodes, public grid access nodes and switch switching nodes. The set of connecting edges includes green electricity direct connection lines, internal distribution lines, grid-connected lines, surplus electricity grid connection channels and fault switching paths.

[0012] As a preferred implementation method, preferably, in step S2 of this scheme, the grid-connected and direct-connected dual-channel energy supply model includes a green electricity direct-connection power supply model, a public grid supplementary power supply model, an energy storage charging and discharging regulation model, and a surplus green electricity grid connection model.

[0013] Step S2 further includes: establishing the following power balance relationship within any time segment, defined as follows:

[0014] in, This indicates the actual usable output of green electricity. Indicates the supplementary power supply capacity of the public power grid. Indicates the energy storage discharge power. Indicates the user load power. Indicates the energy storage charging power. Indicates the remaining power supplied to the grid. This indicates the power loss during line and transformation.

[0015] As a preferred implementation method, preferably, in step S3 of this scheme, the access capacity and load carrying capacity boundary information includes one or more of the following: source-side capacity boundary, public grid access capacity boundary, surplus power grid connection capacity boundary, direct connection line capacity boundary, energy storage access location boundary, and critical load power supply reliability boundary.

[0016] In step S3, the analysis of access capacity and load carrying capacity includes: analyzing the maximum power receiving capacity, maximum grid connection capacity, short-circuit capacity, voltage fluctuation tolerance, power flow distribution impact and protection coordination conditions of the public power grid access point, and analyzing the distribution of load centers within the project, the power transmission radius of direct connection lines, the voltage level of key nodes, the location of energy storage access and / or the power supply reliability requirements of key loads.

[0017] As a preferred implementation method, in step S4 of this scheme, the preset decision variables include one or more of the following: new energy construction capacity, energy storage configuration scale, direct connection line capacity level, public grid access capacity, surplus power grid connection capacity, and phased construction sequence.

[0018] The constraints include power balance constraints, equipment capacity constraints, grid connection capacity constraints, energy storage operation constraints, power supply reliability constraints, N-1 verification constraints, and / or construction period constraints.

[0019] As a preferred implementation method, preferably, in step S4 of this scheme, the comprehensive planning evaluation objective of the source-load-storage collaborative planning model satisfies:

[0020] in, Indicates the comprehensive planning evaluation objectives. Indicates the project construction investment cost. Indicates operating costs, Indicates the green electricity substitution rate, Indicates the power grid impact index, Indicators representing power supply risk. Indicates the planning expansion index, , , , , , This represents the weighting coefficient.

[0021] In step S4, the energy storage operation constraints include energy storage charging power constraints, energy storage discharging power constraints, energy storage state of charge constraints, and charge / discharge mutual exclusion constraints, wherein the energy storage state of charge constraints satisfy:

[0022] in, Indicates energy storage in the first State of charge within a time segment Indicates the lower limit of the energy storage's state of charge. This indicates the upper limit of the energy storage state of charge.

[0023] As a preferred implementation method, in step S5 of this scheme, based on the existing capacity, load growth data, new energy resource development data, energy storage operation evaluation data, and public grid access conditions, the corresponding stage's new power supply capacity, new energy storage scale, direct connection line expansion plan, public grid access adjustment plan, and surplus power grid connection capacity adjustment plan are determined.

[0024] In step S5, at the first In each construction phase, based on the capacity combination formed in the previous construction phase and the updated input of the current construction phase, the new construction scale of the current construction phase is determined, satisfying the following:

[0025] in, Indicates the first The new construction scale of each construction phase Indicates the first Capacity combinations planned after each construction phase This indicates the capacity combination that has been formed in the previous construction phase.

[0026] As a preferred implementation method, preferably, in step S6 of this solution, the operating scenarios include high output low load scenario, low output high load scenario, public power grid fault scenario, direct connection line fault scenario, energy storage shutdown scenario and / or maintenance switching scenario.

[0027] In step S6, the verification includes power flow verification, voltage verification, power supply continuity verification, energy storage backup capacity verification, and / or green electricity utilization rate verification.

[0028] In step S6, if any of the following occurs under any operating scenario: line overload, node voltage exceeding limit, insufficient public grid access capacity, insufficient energy storage backup capacity, green electricity curtailment rate exceeding the preset threshold, or critical load power supply reliability not meeting the preset requirements, return to step S4 to correct at least one of the following: new energy construction capacity, energy storage configuration scale, direct connection line capacity level, public grid access capacity, surplus electricity grid connection capacity, and phased construction sequence.

[0029] As a preferred implementation method, in step S7 of this scheme, the comprehensive planning scheme includes the source-side construction scale, energy storage configuration location and scale, direct connection line topology and capacity level, public grid access scheme, surplus power grid connection scheme, phased implementation route, investment estimation and / or operation control principles.

[0030] Based on the above, this solution also proposes a source-load-storage collaborative planning system for grid-connected green energy direct-connection projects, which includes: The planning boundary modeling module is used to acquire basic planning data for grid-connected green electricity direct connection projects, determine the project planning boundary based on the basic planning data, and construct a planning object topology structure including power source objects, direct connection line objects, user load objects, energy storage objects, and public grid access point objects. The dual-channel energy supply analysis module is used to establish a grid-connected and direct-connected dual-channel energy supply model based on the topology of the planned object, and to determine the energy supply coordination rules between direct-connected green electricity supply, energy storage differential adjustment, public grid supplementary power supply, and surplus electricity grid connection. The access capacity assessment module is used to analyze the access capacity and load carrying capacity of the public grid access point and the internal power supply network of the project, and obtain the source-side capacity boundary, the public grid access capacity boundary, the surplus power grid connection capacity boundary, the direct connection line capacity boundary, the energy storage access location boundary, and the critical load power supply reliability boundary. The collaborative planning and solving module is used to construct and solve the source-load-storage collaborative planning model using new energy construction capacity, energy storage configuration scale, direct connection line capacity level, public grid access capacity, surplus power grid connection capacity, and phased construction sequence as decision variables. The phased expansion module is used to establish a phased construction and rolling expansion mechanism based on the source-load-storage collaborative planning model, and to determine the new power supply capacity, new energy storage scale, direct connection line expansion plan, public grid access adjustment plan, and surplus power grid connection capacity adjustment plan according to different construction stages. The safety verification module is used to perform simulation and safety verification of the phased planning scheme execution scenario, and to feed back decision variable correction information to the collaborative planning solution module based on the verification results; The planning output module is used to output a comprehensive planning scheme and engineering implementation list for grid-connected green electricity direct connection projects based on the planning results after safety verification.

[0031] As a preferred implementation method, a feedback interface is preferably provided between the safety verification module and the collaborative planning solution module in this scheme. The feedback interface is used to feed back the line overload information, node voltage limit information, insufficient energy storage backup capacity information, insufficient public grid access capacity information, and insufficient green electricity utilization information obtained from the operation scenario simulation and safety verification to the collaborative planning solution module, so as to revise the decision variables of the source-load-storage collaborative planning model.

[0032] By adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art: The present invention determines the physical boundary and power boundary of the grid-connected green electricity direct connection project, and constructs a planning object topology structure that includes power supply side objects, direct connection line objects, user load objects, energy storage objects and public grid access point objects, so that the object relationship between green electricity direct supply, grid supplementation, energy storage regulation and surplus electricity grid connection in the project is clearly expressed, and the problem of unclear division of direct connection links, grid-connected links and load boundaries in traditional planning is solved.

[0033] The present invention also establishes a dual-channel energy supply model of grid connection and direct connection, which incorporates the priority supply of direct-connected green electricity to local loads, the participation of energy storage in differential regulation, the supplementary power supply of the public grid, and the grid connection of surplus green electricity into a unified power balance relationship. This can truly reflect the operation mode of grid-connected green electricity direct connection projects and improve the green electricity substitution rate, energy storage utilization efficiency, and the rationality of the public grid supplementary power supply configuration.

[0034] The present invention's solution simultaneously considers the new energy construction capacity, energy storage configuration scale, direct connection line capacity level, public grid access capacity, surplus power grid connection capacity, and phased construction sequence in the source-load-storage collaborative planning model, so that the source, load, storage, and grid are no longer planned in isolation, which can reduce investment waste and operational risks caused by the mismatch between source capacity, grid access capacity, energy storage scale, and load demand.

[0035] This invention analyzes grid connection capacity and load carrying capacity, incorporating the maximum power receiving capacity, maximum grid connection capacity, short-circuit capacity, voltage fluctuation tolerance, power flow distribution impact, and protection coordination conditions of the public power grid into planning constraints. This allows for the early identification of engineering risks such as grid connection infeasibility, node voltage exceeding limits, line overload, and insufficient protection coordination during the planning stage, thereby improving the feasibility of grid connection in the planning scheme.

[0036] The present invention introduces a phased construction and rolling expansion mechanism, which can dynamically revise the planning scheme according to load growth, new energy resource development, energy storage operation assessment and changes in public grid access conditions, avoiding one-time over-investment, while reserving expansion space for long-term load growth and surplus power grid connection capacity improvement.

[0037] The present invention uses simulations of typical scenarios such as high output and low load, low output and high load, public grid failure, direct line failure, energy storage withdrawal and maintenance switching to verify the power flow, voltage, power supply continuity, energy storage backup capacity and green electricity utilization of the planning scheme. The verification results are fed back to the collaborative planning model for correction, thereby improving the engineering safety, operational robustness and implementation feasibility of the planning results. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a simplified implementation flowchart of the planning method of the present invention; Figure 2 This is a schematic diagram of the unit module connection of the planning system of the present invention. Detailed Implementation

[0040] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be particularly noted that the following embodiments are for illustrative purposes only and do not limit the scope of the invention. Similarly, the following embodiments are only some, not all, embodiments of the present invention, and all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] like Figure 1 As shown in the figure, this embodiment presents a source-load-storage coordinated planning method for grid-connected green energy direct-connection projects, which includes: S1. Obtain basic planning data for grid-connected green electricity direct connection projects; determine the project planning boundary based on the basic planning data, and construct the planning object topology based on the project planning boundary; S2. Based on the topology of the planned object, establish a dual-channel energy supply model of grid connection and direct connection, and establish energy supply coordination rules between direct connection channel and grid connection channel according to the operation sequence of priority supply of green electricity to local load, participation of energy storage in differential regulation, supplementary power supply of public grid and grid connection of surplus green electricity. S3. Based on the grid-connected and direct-connected dual-channel power supply model, analyze the access capacity and load carrying capacity of the public power grid access point and the internal power supply network of the project to obtain the access capacity and load carrying capacity boundary information. S4. Construct a source-load-storage collaborative planning model using preset decision variables; the source-load-storage collaborative planning model takes project investment and operating costs, green electricity substitution rate, power supply reliability, grid impact degree and / or planning expansion capacity as planning evaluation targets, and sets constraints in combination with access capacity and load carrying capacity boundary information; S5. Based on the source-load-storage collaborative planning model, establish a phased construction and rolling expansion mechanism, divide the planning cycle into multiple construction phases, and determine the adjustment scheme according to the preset conditions in each construction phase to obtain a phased planning scheme. S6. Perform operational scenario simulation and safety verification on the phased planning scheme formed in step S5. Perform verification under the operational scenario and correct the decision variables in the source-load-storage collaborative planning model according to the verification results. S7. Based on the planning results after safety verification, output the comprehensive planning scheme and engineering implementation list for grid-connected green electricity direct connection projects.

[0042] Regarding the types of basic planning data, as a preferred implementation method, in step S1 of this scheme, the basic planning data includes one or more of the following: new energy resource data, user load data, energy storage deployment conditions, direct connection line conditions, public power grid access point data, and project construction timeline data.

[0043] Meanwhile, the project planning boundary includes one or more of the following: power supply side objects, direct connection line objects, user load objects, energy storage objects, and public grid access point objects.

[0044] Regarding the structural form of the topology of the planning object, in step S1 of this scheme, the topology of the planning object is represented by a set of nodes and a set of connecting edges. The set of nodes includes new energy power nodes, load nodes, energy storage nodes, public grid access nodes and switch switching nodes. The set of connecting edges includes green electricity direct connection lines, internal distribution lines, grid-connected lines, surplus electricity grid connection channels and fault switching paths.

[0045] Step S1 of this plan primarily addresses the issues of unclear planning object boundaries, the mixing of direct power supply ranges and public grid power supply ranges, and the lack of a unified expression for surplus power grid connection paths and fault switching paths in grid-connected green energy direct connection projects. Since these projects include both direct power supply links from renewable energy sources and public grid connection channels, without first clearly defining the boundaries of power sources, loads, energy storage, direct connection lines, and grid connection points, it will be impossible to accurately establish power balance relationships, access capacity constraints, and source-load-storage collaborative planning models.

[0046] As an example of implementation, step S1 of this solution includes the following sub-steps: In step S1, the basic planning data of the project is first obtained. The basic planning data includes new energy resource data, load power consumption data, energy storage layout conditions, direct connection line path conditions, public power grid access point data, user power supply reliability requirements, geospatial data, and project phased construction constraint data.

[0047] The new energy resource data includes wind speed series, solar irradiance series, exploitable installed capacity, power output forecast curve, and power output fluctuation characteristics; the load power consumption data includes user maximum load, typical daily load curve, annual load growth rate, critical load ratio, and interruptible load ratio; the energy storage deployment conditions include energy storage candidate locations, configurable power range, configurable capacity range, and access voltage level; and the public grid access point data includes access point voltage level, maximum receiving capacity, maximum grid connection capacity, short-circuit capacity, voltage fluctuation tolerance, and protection configuration conditions.

[0048] Then, the various objects in the grid-connected green electricity direct connection project are abstracted into nodes and connecting edges to construct the planning object topology:

[0049] in, This indicates the topology of the planning objects for grid-connected green energy direct connection projects; Represents a set of nodes; This represents the set of connecting edges.

[0050] The node set can be further represented as:

[0051] in, Represents the set of new energy power nodes; Represents the set of user load nodes; Represents a set of energy storage nodes; Represents the set of nodes at the public power grid access point; It represents a set of control nodes for switching, metering, protection, and transfer.

[0052] The set of connecting edges can be further represented as:

[0053] in, This represents the set of green electricity direct connection lines; This represents the collection of power distribution lines within the project; This represents the set of public power grid connection lines; This represents a set of channels for surplus electricity to access the internet; This represents the set of failover paths.

[0054] To facilitate subsequent calculations, the topology is transformed into an adjacency matrix:

[0055] in:

[0056] Under the above model logic, the power source, load, energy storage, and public grid connection point in a grid-connected green electricity direct connection project are all electrical objects capable of power exchange, and therefore can be abstracted as nodes; direct connection lines, grid-connected lines, internal distribution lines, and fault switching paths all undertake the energy transmission function between nodes, and therefore can be abstracted as connection edges. By combining the set of nodes and the set of connection edges, the originally scattered equipment objects can be transformed into a unified electrical topology model.

[0057] Furthermore, to distinguish between the project's physical boundaries and electrical boundaries, node boundary identifier variables are set:

[0058] This leads to the project's physical boundaries:

[0059] in, Represents the set of nodes within the physical boundaries of the project; Indicates the first One node; Indicates the first Boundary identifier variables for each node.

[0060] At the same time, establish a set of energy boundary conditions:

[0061] in, This indicates the amount of electricity directly supplied to local loads via green electricity; This indicates the amount of electricity supplied to the public power grid. Indicates the amount of electricity regulated by the charging and discharging of energy storage; Indicates the amount of remaining electricity that is fed into the grid; This indicates the power loss during line and transformation processes.

[0062] Step S1 outputs the topology of the planning object. Adjacency matrix Physical boundary set and the set of electrical boundary These data will serve as the input basis for establishing the dual-channel power supply model in step S2.

[0063] Step S2 of this scheme mainly addresses the issues of unclear energy supply logic between the direct power supply channel and the public grid connection channel in grid-connected green electricity direct connection projects, as well as the lack of a unified power balance relationship among green electricity consumption, energy storage regulation, grid supplementation, and surplus electricity grid connection. The role of this step is to further transform the topology boundary obtained in step S1 into a computable operating power model.

[0064] As a preferred implementation method, preferably, in step S2 of this scheme, the grid-connected and direct-connected dual-channel energy supply model includes a green electricity direct-connection power supply model, a public grid supplementary power supply model, an energy storage charging and discharging regulation model, and a surplus green electricity grid connection model.

[0065] Step S2 further includes: establishing the following power balance relationship within any time segment, defined as follows:

[0066] in, This indicates the actual usable output of green electricity. Indicates the supplementary power supply capacity of the public power grid. Indicates the energy storage discharge power. Indicates the user load power. Indicates the energy storage charging power. Indicates the remaining power supplied to the grid. This indicates the power loss during line and transformation.

[0067] As an example of implementation, step S2 of this solution includes the following sub-steps: In step S2, the topology of the planning object obtained in step S1 is... Physical boundary set and the set of electrical boundary A green electricity direct power supply model, a public grid supplementary power supply model, an energy storage charging and discharging regulation model, and a surplus electricity grid connection model were established respectively.

[0068] At any given time interval (t), according to the law of conservation of electrical energy, the power balance within the project satisfies:

[0069] Under the logic of this formula, within the same time frame, the available input power of the system includes the output power of green electricity sources, the supplementary power supply power from the public grid, and the discharge power of energy storage; the power consumption directions of the system include user loads, energy storage charging, surplus electricity fed into the grid, and line and transformation losses. According to the principle of instantaneous power balance in power systems, the sum of input-side power should equal the sum of output-side power and losses, thus obtaining the above power balance model.

[0070] in, Indicates the first The actual usable output of green electricity at each time segment; Indicates the first Supplemental power supply to the public power grid at each time segment; Indicates the first Energy storage discharge power at each time segment; Indicates the first User load power at each time segment; Indicates the first Energy storage charging power at each time segment; Indicates the first The residual power supply at each time segment; Indicates the first Line and transformation power loss at each time section.

[0071] The actual usable output of green electricity can be further expressed as:

[0072] Under the logic of this formula, green power sources mainly include new energy types such as photovoltaic and wind power. During the planning stage, the installed capacity of a certain type of new energy can be multiplied by its unit capacity output coefficient to obtain the available output of that type of power source at the corresponding time section. When the project includes both photovoltaic and wind power, the total available green power output can be obtained by adding the output of the two types of power sources.

[0073] in, Indicates photovoltaic installed capacity; Indicates the first Photovoltaic unit capacity output coefficient at a time segment; Indicates wind power installed capacity; Indicates the first Wind power output coefficient per unit capacity at a given time point.

[0074] Regarding energy supply coordination rules, priority will be given to supplying local loads with green electricity directly connected to the grid. The power supplied by green electricity directly connected to the grid is as follows:

[0075] in, Indicates the first The power of green electricity directly supplied to local loads within a time segment. The reasoning behind this formula is as follows: if the green electricity output is less than the load demand, then all green electricity is used for local loads; if the green electricity output is greater than the load demand, then the local load can only absorb a maximum of green electricity power equal to the load demand, therefore the smaller of the two values ​​is taken.

[0076] When a load gap still exists after direct green electricity supply, the load gap is expressed as:

[0077] in, ; Indicates the first The load gap power at each time section.

[0078] Energy storage prioritizes participation in load gap regulation, and its dischargeable power is constrained by rated power and state of charge, satisfying the following:

[0079] in, Indicates the maximum discharge power of the energy storage; This indicates the energy storage state of charge at the previous time point. This indicates the minimum permissible state of charge for energy storage; Indicates the rated energy capacity of the energy storage; Indicates the energy storage discharge efficiency; Indicates the time step.

[0080] Under the logic of this formula, the energy storage discharge power cannot exceed the current load gap, cannot exceed the rated maximum discharge power of the energy storage, and cannot exceed the maximum discharge power of the energy storage that can be released within the time step. Therefore, the minimum value among the three is taken.

[0081] For loads that still cannot be met after direct connection with green electricity and energy storage discharge, supplementary power will be supplied from the public power grid:

[0082] When the output of green electricity exceeds the local load, the surplus green electricity power is:

[0083] Prioritizing the use of surplus green electricity to charge energy storage, then the first... The energy storage charging power of a time segment is defined as:

[0084] in, Indicates the maximum charging power of the energy storage; Indicates the maximum permissible state of charge for energy storage; Indicates energy storage charging efficiency; Indicates the rated energy capacity of the energy storage; It indicates the energy storage state of charge at the previous time segment.

[0085] After meeting local consumption and energy storage requirements, the remaining green electricity can be connected to the public grid through the grid connection point. The surplus power connected to the grid is... It is represented as follows:

[0086] in, This indicates the maximum allowable power output at the public power grid connection point.

[0087] Step S2 is used to obtain the green electricity direct supply power at each time segment. Supplemental power supply from the public power grid Energy storage charging power Energy storage and discharge power Residual power grid connection power and energy storage state of charge These time-series data will serve as the basic inputs for access capability analysis in step S3 and the construction of the collaborative planning model in step S4.

[0088] Step S3 of this plan mainly addresses the mismatch between the source-side capacity, direct-connection line capacity, energy storage access method, and public grid access capacity. Without analyzing the public grid access point's carrying capacity and the project's internal network load capacity, problems may arise such as excessively large renewable energy installations leading to surplus power not being able to connect to the grid, voltage exceeding limits at the access point, line overload, or inadequate protection coordination.

[0089] As a preferred implementation method, preferably, in step S3 of this scheme, the access capacity and load carrying capacity boundary information includes one or more of the following: source-side capacity boundary, public grid access capacity boundary, surplus power grid connection capacity boundary, direct connection line capacity boundary, energy storage access location boundary, and critical load power supply reliability boundary.

[0090] In step S3, the analysis of access capacity and load carrying capacity includes: analyzing the maximum power receiving capacity, maximum grid connection capacity, short-circuit capacity, voltage fluctuation tolerance, power flow distribution impact and protection coordination conditions of the public power grid access point, and analyzing the distribution of load centers within the project, the power transmission radius of direct connection lines, the voltage level of key nodes, the location of energy storage access and / or the power supply reliability requirements of key loads.

[0091] As an example of implementation, step S3 of this solution includes the following sub-steps: In step S3, based on the grid-connected and direct-connected dual-channel power supply model obtained in step S2, the access capacity and load-bearing capacity of the public power grid access point and the project's internal power supply network are analyzed.

[0092] First, based on the supplementary power supply sequence of the public power grid obtained in step S2, calculate the maximum power receiving capacity required by the project:

[0093] in, Indicates the required public power grid capacity for the project; Represents the set of planning time segments; Indicates the first Supplemental power supply to the public power grid at each time segment.

[0094] Based on the surplus power grid connection sequence obtained in step S2, calculate the maximum grid connection capacity required for the project:

[0095] in, This indicates the required surplus power capacity to be connected to the grid for the project; Indicates the first The residual power grid connection capacity of a time segment.

[0096] Under the above formula logic, the public grid access capacity needs to cover the maximum power demand within the planning period, and the surplus power grid connection capacity needs to cover the maximum back-feeding demand within the planning period. Therefore, the maximum value is taken for the power received and the power grid connected in the time series, respectively.

[0097] The public power grid access capacity should meet the following requirements:

[0098]

[0099] in, Indicates the maximum allowable power receiving capacity of the public power grid; This indicates the maximum allowable grid connection capacity of the public power grid.

[0100] Secondly, a thermal stability load-bearing capacity analysis was performed on the direct-connection lines and internal power distribution lines. For the connection nodes... and nodes The line has the following apparent power:

[0101] The line current is:

[0102] Line load-bearing constraints are satisfied:

[0103] in, Indicates the first Line at a specific time section Apparent power transmitted uplink; Indicates the line Active power transmitted upstream; Indicates the line Reactive power transmitted upstream; Indicates the line Current on; Indicates the line Operating voltage; Indicates the line Maximum allowable flow rate.

[0104] Under the logic of this formula, the AC line capacity is determined by both active power and reactive power. Therefore, the apparent power is first calculated from the active power and reactive power, and then the line current is calculated according to the three-phase AC power relationship. The line current is then compared with the maximum allowable current carrying capacity to determine whether the line is overloaded.

[0105] Next, constraint analysis is performed on the node voltages. For the node... Its voltage should meet the following requirements:

[0106] in, Indicates the first The node at the th Operating voltage at each time segment; This represents the lower limit of the voltage allowed at node (i); Represents a node The maximum allowable voltage.

[0107] In planning calculations, an approximate relationship of line voltage drop can be used for preliminary judgment:

[0108] in, Indicates the line In the Voltage drop at a time interval; Indicates the line The resistance; Indicates the line The reactance; Indicates the line Active power transmitted upstream; Indicates the line Reactive power transmitted upstream; Indicates the line Operating voltage.

[0109] Under the logic of this formula, in the distribution network planning and analysis, the line voltage drop is mainly caused by active power flowing through the resistor and reactive power flowing through the reactance. Therefore, the node voltage deviation can be approximately calculated by the line impedance and power flow data, which can be used to determine whether the length of the direct connection line, the capacity level, and the location of energy storage access are reasonable.

[0110] Through the above steps, this scheme can obtain relevant supply and demand boundary information such as source-side capacity boundary, public grid access capacity boundary, surplus power grid connection capacity boundary, direct connection line capacity boundary, energy storage access location boundary, and critical load power supply reliability boundary, so as to assist in constructing the constraints of the source-load-storage collaborative planning model in the subsequent step S4.

[0111] Traditional planning separates the construction capacity of new energy sources, the scale of energy storage, the capacity of direct connection lines, the grid connection capacity, and the construction sequence, which can easily lead to inconsistencies in the overall scheme's economy, reliability, and feasibility. This scheme incorporates the operating power relationship formed in step S2 and the boundary conditions formed in step S3 into a unified optimization model, achieving coordinated planning of sources, loads, storage, and the grid.

[0112] As a preferred implementation method, in step S4 of this scheme, the preset decision variables include one or more of the following: new energy construction capacity, energy storage configuration scale, direct connection line capacity level, public grid access capacity, surplus power grid connection capacity, and phased construction sequence.

[0113] The constraints include power balance constraints, equipment capacity constraints, grid connection capacity constraints, energy storage operation constraints, power supply reliability constraints, N-1 verification constraints, and / or construction period constraints.

[0114] As a preferred implementation method, preferably, in step S4 of this scheme, the comprehensive planning evaluation objective of the source-load-storage collaborative planning model satisfies:

[0115] in, Indicates the comprehensive planning evaluation objectives. Indicates the project construction investment cost. Indicates operating costs, Indicates the green electricity substitution rate, Indicates the power grid impact index, Indicators representing power supply risk. Indicates the planning expansion index, , , , , , This represents the weighting coefficient.

[0116] In step S4, the energy storage operation constraints include energy storage charging power constraints, energy storage discharging power constraints, energy storage state of charge constraints, and charge / discharge mutual exclusion constraints, wherein the energy storage state of charge constraints satisfy:

[0117] in, Indicates energy storage in the first State of charge within a time segment Indicates the lower limit of the energy storage's state of charge. This indicates the upper limit of the energy storage state of charge.

[0118] As an example, step S4 of this solution includes the following sub-steps: In step S4, the decision variables of the source-load-storage collaborative planning model are set as follows:

[0119] in, This represents the set of decision variables for source-load-storage collaborative planning; This indicates the total installed capacity of new energy sources; Indicates the rated power of energy storage; Indicates the rated energy capacity of the energy storage; Indicates the capacity level of the direct connection line; Indicates the capacity connected to the public power grid; Indicates the remaining power capacity to the grid; Indicates the first The timeline for commissioning each construction phase.

[0120] To ensure that all planning objectives have a unified evaluation scale, a comprehensive objective function is constructed:

[0121] Under this formula, the planning objectives of grid-connected green electricity direct connection projects are not only to reduce investment and operating costs, but also to increase the green electricity substitution rate, reduce the impact on the public power grid, reduce power supply risks, and improve future expansion capabilities. Since investment costs, operating costs, green electricity substitution rate, grid impact indicators, and risk indicators have different dimensions, cost-related indicators are normalized, and the green electricity substitution rate and expansion capabilities are converted into penalty terms to be minimized, thus forming a unified minimization objective function.

[0122] in, This represents the value of the objective function in the comprehensive planning. This represents the normalized construction investment cost; This represents the normalized operating cost; Indicates the green electricity substitution rate; Indicates the power grid impact index; Indicates power supply risk indicators; Indicators representing the planning expansion capacity; - This represents the weight coefficient of the corresponding indicator, and satisfies... .

[0123] Construction investment costs can be expressed as:

[0124] in, Indicates construction investment cost; This indicates the investment cost per unit of new energy capacity; This indicates the investment cost per unit of energy storage capacity; This indicates the investment cost per unit of energy storage capacity; This indicates the investment cost per unit line capacity and per unit length; Indicates the length of the direct connection line; This indicates the investment cost per unit of public power grid access capacity.

[0125] Operating costs can be expressed as:

[0126] in, Indicates operating costs; Indicates the first Electricity purchase price at a specific time point; Indicates the first The on-grid electricity price for a specific time segment; This represents the cost coefficient for the operation and maintenance of new energy sources; This represents the energy storage charging and discharging loss cost coefficient; Indicates the time step.

[0127] The green electricity substitution rate can be expressed as:

[0128] in, Indicates the first The green power actually consumed by local loads within a time segment includes the green power directly supplied to the load and the power that is charged into energy storage and then released to supply the load. Indicates the first User load power at each time segment; Indicates the time step.

[0129] The model constraints include the following.

[0130] First, the power balance constraint follows the power balance relationship from step S2:

[0131] in, Indicates the first The actual usable output of green electricity at each time segment; Indicates the first Supplemental power supply to the public power grid at each time segment; Indicates the first Energy storage discharge power at each time segment; Indicates the first User load power at each time segment; Indicates the first Energy storage charging power at each time segment; Indicates the first The residual power supply at each time segment; Indicates the first Line and transformation power loss at each time section.

[0132] Secondly, the grid access capacity constraint comes from step S3:

[0133]

[0134]

[0135]

[0136] Furthermore, the energy storage operation constraints are satisfied:

[0137]

[0138]

[0139]

[0140] in, Indicates the first State of charge of energy storage at a time segment; Indicates the time step.

[0141] Under the logic of this energy storage state update formula, the current state of charge of the energy storage is equal to the state of charge at the previous time segment, plus the proportion of energy actually entering the energy storage after charging, and then minus the proportion of energy consumed from the energy storage during discharging. Charging efficiency is considered during charging, and discharging efficiency is considered during discharging, thus forming the above recursive relationship.

[0142] Direct connection capacity Constraints satisfied:

[0143] in, Indicates the connection node and nodes The capacity level of the direct connection line.

[0144] Through step S4, this scheme can obtain initial planning results that meet the requirements of economy, green electricity substitution rate, grid adaptability, power supply reliability, and scalability. The initial planning results will serve as the basis for phased construction and rolling expansion design in step S5.

[0145] To address the challenges of excessive initial investment, uncertain long-term load growth, and difficulty in synchronizing resource development pace with changes in grid-connected green energy projects, step S5 of this plan breaks down the overall planning results obtained in step S4 into multiple implementable phases. This ensures that the planning scheme meets both near-term construction needs and long-term scalability.

[0146] As a preferred implementation method, in step S5 of this scheme, based on the existing capacity, load growth data, new energy resource development data, energy storage operation evaluation data, and public grid access conditions, the corresponding stage's new power supply capacity, new energy storage scale, direct connection line expansion plan, public grid access adjustment plan, and surplus power grid connection capacity adjustment plan are determined.

[0147] In step S5, at the first In each construction phase, based on the capacity combination formed in the previous construction phase and the updated input of the current construction phase, the new construction scale of the current construction phase is determined, satisfying the following:

[0148] in, Indicates the first The new construction scale of each construction phase Indicates the first Capacity combinations planned after each construction phase This indicates the capacity combination that has been formed in the previous construction phase.

[0149] As an example of implementation, step S5 of this solution includes the following sub-steps: In step S5, the entire planning cycle is divided into multiple construction phases:

[0150] in, Represents the set of construction phases; This indicates the total number of construction phases.

[0151] For the During each construction phase, update the load forecast data, new energy resource development data, energy storage operation assessment data, and public grid connection conditions for that phase. The phase load can be represented as:

[0152] in, Indicates the first The construction phase is in the first Predicted load for each time segment; The reference stage is in the first stage. Load at a time cross section; Indicates the first The load growth factor of each construction phase relative to the baseline phase.

[0153] Under this formula logic, during the planning stage, the long-term load is usually based on the baseline load, and the growth coefficient is determined according to the user's capacity growth, park expansion or equipment commissioning plan. Therefore, the stage load forecast value can be obtained by multiplying the baseline load by the growth coefficient.

[0154] Among them, the The capacity combination for each construction phase is represented as follows:

[0155] in, Indicates the first The capacity combination formed in each construction phase; Indicates the first Total new energy construction capacity in each phase; Indicates the first Rated energy storage power for each stage; Indicates the first Rated energy capacity of energy storage at each stage; Indicates the first The capacity level of direct connection lines at each stage; Indicates the first Public grid access capacity at each stage; Indicates the first The surplus power capacity to the grid in each stage.

[0156] The current phase of new construction scale is as follows:

[0157] During project implementation, since existing equipment cannot usually be reduced arbitrarily, it can be further limited to:

[0158] in, Indicates the first The new construction scale of each construction phase relative to the previous phase; Indicates the first The capacity combination already formed in each construction phase.

[0159] Under the logic of this formula, the essence of phased construction is to determine the incremental construction content based on the capacity already built in the previous stage, according to the new load, the new green electricity replacement target, and changes in access conditions. Therefore, the new construction scale can be obtained by subtracting the capacity already built in the previous stage from the target capacity of the current stage; if a certain type of capacity does not need to be increased in the current stage, the new construction scale is zero.

[0160] Furthermore, to avoid limitations on future expansion, a phased expansion margin is set:

[0161] in, Indicates the first Expansion margin for each construction phase; Indicates the first Expandable capacity reserved for each construction phase; Indicates the first The required capacity is predicted for each construction phase.

[0162] when When the capacity is below the preset expansion margin threshold, it indicates that the line, access point or energy storage layout conditions at this stage are insufficient to support subsequent capacity expansion, and it is necessary to reserve equipment interfaces, civil engineering conditions or access capacity in the current stage.

[0163] Through step S5, this scheme can obtain the corresponding new power supply capacity, new energy storage scale, direct connection line expansion plan, public grid access adjustment plan, and surplus power grid connection adjustment plan for each construction phase. The results of this phased planning will serve as the input for the operational scenario simulation and safety verification in step S6.

[0164] To address the issues of insufficient safety and lack of verification of engineering feasibility in the optimized planning results under typical operational disturbances and failure scenarios, even if steps S4 and S5 have yielded economically superior planning results, it is still necessary to verify their safety and stability through scenarios such as high output and low load, low output and high load, grid connection failure, direct connection line failure, and energy storage withdrawal from operation.

[0165] As a preferred implementation method, preferably, in step S6 of this solution, the operating scenarios include high output low load scenario, low output high load scenario, public power grid fault scenario, direct connection line fault scenario, energy storage shutdown scenario and / or maintenance switching scenario.

[0166] In step S6, the verification includes power flow verification, voltage verification, power supply continuity verification, energy storage backup capacity verification, and / or green electricity utilization rate verification.

[0167] In step S6, if any of the following occurs under any operating scenario: line overload, node voltage exceeding limit, insufficient public grid access capacity, insufficient energy storage backup capacity, green electricity curtailment rate exceeding the preset threshold, or critical load power supply reliability not meeting the preset requirements, return to step S4 to correct at least one of the following: new energy construction capacity, energy storage configuration scale, direct connection line capacity level, public grid access capacity, surplus electricity grid connection capacity, and phased construction sequence.

[0168] As an example of implementation, step S6 of this solution includes the following sub-steps: In step S6, based on the phased planning results output in step S5, a set of operational scenarios is constructed:

[0169] in, Represents a set of running scenarios; Indicates the first One operating scenario.

[0170] The output and load power of new energy sources under each operating scenario can be expressed as:

[0171]

[0172] in, Representing a scene Next The available output of green electricity at each time segment; Representing a scene The correction factor for new energy output is as follows; Representing a scene Next Load power at each time segment; Representing a scene Load correction factor; Indicates the first The actual usable output of green electricity at each time segment; Indicates the first User load power at a given time interval.

[0173] Under this formula, different operating scenarios can be simulated by scaling up or down the benchmark renewable energy output and benchmark load. For example, in a high-output, low-load scenario... Larger and Smaller; in low-output, high-load scenarios, Smaller and Larger.

[0174] For equipment failure scenarios, set the equipment availability status variable:

[0175] in, Indicates equipment In the scene The available status under the following conditions. For public power grid fault scenarios, the corresponding public power grid access line can be configured to... For scenarios involving direct-connection line failures, the corresponding direct-connection line can be... For scenarios where energy storage is taken out of service, the corresponding energy storage device can be... .

[0176] In each scenario, the line capacity must meet the following requirements for performing power flow verification:

[0177] in, Representing a scene Next Line at a specific time section Apparent power; Indicates the line In the scene The available status is as follows; Indicates the line Capacity class.

[0178] The node voltage must meet the following requirements:

[0179] in, Representing a scene Next The node at the th Voltage at a time segment.

[0180] Power supply continuity can be verified using the amount of power not supplied as an indicator:

[0181] in, Representing a scene The amount of power not supplied; Representing a scene Next Load power at each time segment; Representing a scene Next The actual power supply at each time segment; For time step.

[0182] The power supply continuity constraint is satisfied as follows:

[0183] in, This indicates the maximum amount of power that can be left unsupplied.

[0184] The green electricity utilization rate verification can be expressed as:

[0185] in, Representing a scene Green electricity utilization rate; Representing a scene Next Green electricity that is consumed by local loads or utilized after being absorbed by energy storage at a given time interval; For time step; Representing a scene Next The available power output of green electricity at each time segment.

[0186] If any scenario occurs, such as line overload, node voltage exceeding limit, insufficient energy storage backup capacity, insufficient public grid access capacity, green electricity curtailment rate exceeding a preset threshold, or critical load power outage exceeding the allowable value, a verification feedback quantity will be generated:

[0187] in, Representing a scene The following capacity adjustment amount requires feedback and correction; This indicates the amount of adjustment to the new energy capacity; Indicates the adjustment amount of energy storage capacity; Indicates the adjustment amount of energy storage capacity; Indicates the capacity adjustment amount for directly connected lines; This indicates the adjustment amount of the public power grid access capacity; This indicates the amount of surplus electricity that can be fed into the grid.

[0188] In this scheme, the above feedback can be returned to steps S4 and S5 to revise the source-load-storage collaborative planning model and phased construction plan, forming a closed-loop process of "planning solution - phased decomposition - scenario verification - feedback correction".

[0189] To address the issues of planning calculation results being difficult to directly translate into engineering implementation documents, and the lack of an executable list and key verification indicators in planning schemes, step S7 of this scheme organizes the model results verified in step S6 into planning deliverables that can be directly used in project initiation, feasibility studies, preliminary design, and engineering implementation.

[0190] As a preferred implementation method, in step S7 of this scheme, the comprehensive planning scheme includes the source-side construction scale, energy storage configuration location and scale, direct connection line topology and capacity level, public grid access scheme, surplus power grid connection scheme, phased implementation route, investment estimation and / or operation control principles.

[0191] As an example of implementation, step S7 of this solution includes the following sub-steps: In step S7, based on the final planning variables verified in step S6, the final planning result is generated:

[0192] in, Indicates the final planned capacity combination; This indicates the final capacity for new energy construction; Indicates the final rated energy storage capacity; Indicates the final rated energy capacity of energy storage; Indicates the final direct connection capacity level; Indicates the final public grid connection capacity; Indicates the final remaining power capacity to be fed into the grid; This indicates the final phased construction schedule.

[0193] Further calculate the key evaluation indicators of the planning results.

[0194] The green electricity substitution rate is:

[0195] The public grid access margin is:

[0196] The remaining power supply margin is:

[0197] The line capacity margin is:

[0198] in, This indicates the green electricity substitution rate of the final planning scheme; Indicates the first under the final planning scheme Local utilization of green electricity at a given time point; Indicates the first under the final planning scheme Load power at each time segment; Indicates the margin of access to the public power grid; Indicates the remaining power capacity for grid connection; Indicates line capacity margin; Indicates the route under the final planning scheme In the Apparent power at each time segment.

[0199] In this scheme, the green electricity substitution rate is used to reflect the proportion of local load that is met by green electricity; the public grid access margin is used to reflect whether there is sufficient safety margin in the access capacity; the surplus power grid access margin is used to reflect whether the surplus green electricity back-transmission capacity is sufficient; and the line capacity margin is used to reflect whether there is an overload risk in the direct connection lines and internal distribution lines under the most unfavorable power flow.

[0200] After steps S1-S7, the final comprehensive planning scheme output by this solution includes: source-side construction scale, capacity configuration of different types of new energy sources, energy storage configuration location, energy storage power and capacity, direct connection line topology, direct connection line capacity level, public grid access scheme, surplus power grid connection scheme, phased construction route, investment estimate, operation control principles and / or safety verification results for typical scenarios.

[0201] The final output project implementation list includes: a list of new energy power generation equipment, a list of energy storage system equipment, a list of direct connection lines and cables, a list of switch and protection equipment, a list of grid connection equipment, a list of metering and monitoring equipment, a list of communication and dispatch interfaces, a phased commissioning plan, key node verification indicators and / or reserved conditions for subsequent capacity expansion.

[0202] The results output in step S7 enable the boundary identification results, energy supply model, access capacity analysis results, collaborative planning results, phased expansion results, and safety verification results formed in steps S1 to S6 to be uniformly transformed into executable engineering planning results, thereby completing the source-load-storage collaborative planning of grid-connected green electricity direct connection projects.

[0203] Combination Figure 2 As shown, based on the above, this solution also proposes a source-load-storage collaborative planning system for grid-connected green energy direct-connection projects, which includes: The planning boundary modeling module is used to acquire basic planning data for grid-connected green electricity direct connection projects, determine the project planning boundary based on the basic planning data, and construct a planning object topology structure including power source objects, direct connection line objects, user load objects, energy storage objects, and public grid access point objects. The dual-channel energy supply analysis module is used to establish a grid-connected and direct-connected dual-channel energy supply model based on the topology of the planned object, and to determine the energy supply coordination rules between direct-connected green electricity supply, energy storage differential adjustment, public grid supplementary power supply, and surplus electricity grid connection. The access capacity assessment module is used to analyze the access capacity and load carrying capacity of the public grid access point and the internal power supply network of the project, and obtain the source-side capacity boundary, the public grid access capacity boundary, the surplus power grid connection capacity boundary, the direct connection line capacity boundary, the energy storage access location boundary, and the critical load power supply reliability boundary. The collaborative planning and solving module is used to construct and solve the source-load-storage collaborative planning model using new energy construction capacity, energy storage configuration scale, direct connection line capacity level, public grid access capacity, surplus power grid connection capacity, and phased construction sequence as decision variables. The phased expansion module is used to establish a phased construction and rolling expansion mechanism based on the source-load-storage collaborative planning model, and to determine the new power supply capacity, new energy storage scale, direct connection line expansion plan, public grid access adjustment plan, and surplus power grid connection capacity adjustment plan according to different construction stages. The safety verification module is used to perform simulation and safety verification of the phased planning scheme execution scenario, and to feed back decision variable correction information to the collaborative planning solution module based on the verification results; The planning output module is used to output a comprehensive planning scheme and engineering implementation list for grid-connected green electricity direct connection projects based on the planning results after safety verification.

[0204] In this scheme, a feedback interface is set between the safety verification module and the collaborative planning solution module. The feedback interface is used to feed back the line overload information, node voltage limit information, insufficient energy storage backup capacity information, insufficient public grid access capacity information and insufficient green electricity utilization information obtained from the operation scenario simulation and safety verification to the collaborative planning solution module, so as to re-correct the decision variables of the source-load-storage collaborative planning model.

[0205] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0206] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processor to execute all or part of the steps of the methods of various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0207] The above description is only a part of the embodiments of the present invention and does not limit the scope of protection of the present invention. Any equivalent device or equivalent process transformation made based on the content of the present invention specification and drawings, or direct or indirect application in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A source-load-storage coordinated planning method for grid-connected green energy direct-connection projects, characterized in that, It includes: S1. Obtain basic planning data for grid-connected green energy direct connection projects; The project planning boundary is determined based on the basic planning data, and the topology of the planning object is constructed based on the project planning boundary. S2. Based on the topology of the planned object, establish a dual-channel energy supply model of grid connection and direct connection, and establish energy supply coordination rules between direct connection channel and grid connection channel according to the operation sequence of priority supply of green electricity to local load, participation of energy storage in differential regulation, supplementary power supply of public grid and grid connection of surplus green electricity. S3. Based on the grid-connected and direct-connected dual-channel power supply model, analyze the access capacity and load carrying capacity of the public power grid access point and the internal power supply network of the project to obtain the access capacity and load carrying capacity boundary information. S4. Construct a source-load-storage collaborative planning model using preset decision variables; the source-load-storage collaborative planning model takes project investment and operating costs, green electricity substitution rate, power supply reliability, grid impact degree and / or planning expansion capacity as planning evaluation targets, and sets constraints in combination with access capacity and load carrying capacity boundary information; S5. Based on the source-load-storage collaborative planning model, establish a phased construction and rolling expansion mechanism, divide the planning cycle into multiple construction phases, and determine the adjustment scheme according to the preset conditions in each construction phase to obtain a phased planning scheme. S6. Perform operational scenario simulation and safety verification on the phased planning scheme formed in step S5. Perform verification under the operational scenario and correct the decision variables in the source-load-storage collaborative planning model according to the verification results. S7. Based on the planning results after safety verification, output the comprehensive planning scheme and engineering implementation list for grid-connected green electricity direct connection projects.

2. The source-load-storage coordinated planning method for grid-connected green energy direct-connection projects as described in claim 1, characterized in that, In step S1, the basic planning data includes one or more of the following: new energy resource data, user load data, energy storage deployment conditions, direct connection line conditions, public power grid access point data, and project construction timeline data. The project planning boundary includes one or more of the following: power supply side objects, direct connection line objects, user load objects, energy storage objects, and public grid access point objects; In step S1, the topology of the planning object is represented by a set of nodes and a set of connecting edges. The set of nodes includes new energy power nodes, load nodes, energy storage nodes, public grid access nodes and switch switching nodes. The set of connecting edges includes green electricity direct connection lines, internal distribution lines, grid-connected lines, surplus electricity grid connection channels and fault switching paths.

3. The source-load-storage coordinated planning method for grid-connected green energy direct-connection projects as described in claim 1, characterized in that, In step S2, the grid-connected and direct-connection dual-channel energy supply model includes a green electricity direct-connection power supply model, a public grid supplementary power supply model, an energy storage charging and discharging regulation model, and a surplus green electricity grid connection model. Step S2 further includes: establishing the following power balance relationship within any time segment, defined as follows: in, This indicates the actual usable output of green electricity. Indicates the supplementary power supply capacity of the public power grid. Indicates the energy storage discharge power. Indicates the user load power. Indicates the energy storage charging power. Indicates the remaining power supplied to the grid. This indicates the power loss during line and transformation.

4. The source-load-storage coordinated planning method for grid-connected green energy direct-connection projects as described in claim 1, characterized in that, In step S3, the access capacity and load carrying capacity boundary information includes one or more of the following: source-side capacity boundary, public grid access capacity boundary, surplus power grid connection capacity boundary, direct connection line capacity boundary, energy storage access location boundary, and critical load power supply reliability boundary. In step S3, the analysis of access capacity and load carrying capacity includes: analyzing the maximum power receiving capacity, maximum grid connection capacity, short-circuit capacity, voltage fluctuation tolerance, power flow distribution impact and protection coordination conditions of the public power grid access point, and analyzing the distribution of load centers within the project, the power transmission radius of direct connection lines, the voltage level of key nodes, the location of energy storage access and / or the power supply reliability requirements of key loads.

5. The source-load-storage coordinated planning method for grid-connected green energy direct-connection projects as described in claim 1, characterized in that, In step S4, the preset decision variables include one or more of the following: new energy construction capacity, energy storage configuration scale, direct connection line capacity level, public grid access capacity, surplus power grid connection capacity, and phased construction sequence. The constraints include power balance constraints, equipment capacity constraints, grid connection capacity constraints, energy storage operation constraints, power supply reliability constraints, N-1 verification constraints, and / or construction period constraints.

6. The source-load-storage coordinated planning method for grid-connected green energy direct-connection projects as described in claim 5, characterized in that, In step S4, the comprehensive planning evaluation objective of the source-load-storage collaborative planning model satisfies: in, Indicates the comprehensive planning evaluation objectives. Indicates the project construction investment cost. Indicates operating costs, Indicates the green electricity substitution rate, Indicates the power grid impact index, Indicators representing power supply risk. Indicates the planning expansion index, , , , , , Indicates the weighting coefficient; In step S4, the energy storage operation constraints include energy storage charging power constraints, energy storage discharging power constraints, energy storage state of charge constraints, and charge / discharge mutual exclusion constraints, wherein the energy storage state of charge constraints satisfy: in, Indicates energy storage in the first State of charge within a time segment Indicates the lower limit of the energy storage's state of charge. This indicates the upper limit of the energy storage state of charge.

7. The source-load-storage coordinated planning method for grid-connected green energy direct-connection projects as described in claim 1, characterized in that, In step S5, based on the existing capacity, load growth data, new energy resource development data, energy storage operation assessment data, and public grid access conditions, the corresponding stage's new power supply capacity, new energy storage scale, direct connection line expansion plan, public grid access adjustment plan, and surplus power grid connection capacity adjustment plan are determined. In step S5, at the first In each construction phase, based on the capacity combination formed in the previous construction phase and the updated input of the current construction phase, the new construction scale of the current construction phase is determined, satisfying the following: in, Indicates the first The new construction scale of each construction phase Indicates the first Capacity combinations planned after each construction phase This indicates the capacity combination that has been formed in the previous construction phase.

8. The source-load-storage coordinated planning method for grid-connected green energy direct-connection projects as described in claim 1, characterized in that, In step S6, the operating scenarios include high output low load scenario, low output high load scenario, public power grid fault scenario, direct connection line fault scenario, energy storage exit operation scenario and / or maintenance switching scenario. In step S6, the verification includes power flow verification, voltage verification, power supply continuity verification, energy storage reserve capacity verification and / or green electricity utilization rate verification; In step S6, if any of the following occurs under any operating scenario: line overload, node voltage exceeding limit, insufficient public grid access capacity, insufficient energy storage backup capacity, green electricity curtailment rate exceeding the preset threshold, or critical load power supply reliability not meeting the preset requirements, return to step S4 to correct at least one of the following: new energy construction capacity, energy storage configuration scale, direct connection line capacity level, public grid access capacity, surplus electricity grid connection capacity, and phased construction sequence.

9. The source-load-storage coordinated planning method for grid-connected green energy direct-connection projects as described in claim 1, characterized in that, In step S7, the comprehensive planning scheme includes the source-side construction scale, energy storage configuration location and scale, direct connection line topology and capacity level, public grid access scheme, surplus power grid connection scheme, phased implementation route, investment estimation and / or operation control principles.

10. A source-load-storage collaborative planning system for grid-connected green energy direct-connection projects, characterized in that, It includes: The planning boundary modeling module is used to acquire basic planning data for grid-connected green electricity direct connection projects, determine the project planning boundary based on the basic planning data, and construct a planning object topology structure including power source objects, direct connection line objects, user load objects, energy storage objects, and public grid access point objects. The dual-channel energy supply analysis module is used to establish a grid-connected and direct-connected dual-channel energy supply model based on the topology of the planned object, and to determine the energy supply coordination rules between direct-connected green electricity supply, energy storage differential adjustment, public grid supplementary power supply, and surplus electricity grid connection. The access capacity assessment module is used to analyze the access capacity and load carrying capacity of the public grid access point and the internal power supply network of the project, and obtain the source-side capacity boundary, the public grid access capacity boundary, the surplus power grid connection capacity boundary, the direct connection line capacity boundary, the energy storage access location boundary, and the critical load power supply reliability boundary. The collaborative planning and solving module is used to construct and solve the source-load-storage collaborative planning model using new energy construction capacity, energy storage configuration scale, direct connection line capacity level, public grid access capacity, surplus power grid connection capacity, and phased construction sequence as decision variables. The phased expansion module is used to establish a phased construction and rolling expansion mechanism based on the source-load-storage collaborative planning model, and to determine the new power supply capacity, new energy storage scale, direct connection line expansion plan, public grid access adjustment plan, and surplus power grid connection capacity adjustment plan according to different construction stages. The safety verification module is used to perform simulation and safety verification of the phased planning scheme execution scenario, and to feed back decision variable correction information to the collaborative planning solution module based on the verification results; The planning output module is used to output a comprehensive planning scheme and engineering implementation list for grid-connected green electricity direct connection projects based on the planning results after safety verification.

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