Collaborative planning operation scheduling method and system for power distribution network and micro-grid

Abstract

The invention discloses a collaborative planning operation scheduling method and system for a power distribution network and a micro-grid, and the method comprises the steps: obtaining the historical operation data of the power distribution network and the micro-grid, and obtaining typical scene features according to the historical operation data; the typical scene features comprise typical power features; according to the typical scene features and a preset power grid cooperative operation requirement, a constraint condition and a target function are established, and a cooperative planning operation model of the power distribution network and the micro-grid is obtained; the collaborative planning operation model comprises a power grid planning layer and a power grid operation layer; performing linearization conversion on the collaborative planning operation model, and solving the linearized collaborative planning operation model to obtain a configuration and scheduling strategy; and performing configuration and scheduling operation on the power distribution network and the micro-grid by applying the configuration and scheduling strategy. By adopting the embodiment of the invention, the demand response capability of flexible resources can be mined, the economical efficiency of investment is improved, the optimal configuration of the power distribution network and the micro-grid is realized, and meanwhile, the method also has relatively high safety.

Description

Technical Field

[0001] The present invention relates to the technical field of distribution network planning, and in particular to a method and system for collaborative planning, operation and scheduling of a distribution network and a microgrid. Background Art

[0002] With the widespread access of new elements such as distributed power sources and microgrids, the development of distribution networks faces many problems, such as heavy overload of some lines and voltage exceeding the limit. These challenges require consideration of how to use resources more effectively, tap the response potential of new elements, and improve the safety and stability of distribution networks. Coordinated planning of distribution networks and microgrids has become a key way to solve these problems.

[0003] At the same time, distribution network planning faces many uncertain factors such as distributed power output and load demand, which pose great challenges to the safe, stable and economic operation of the distribution network. The existing method of grid planning only from the perspective of distribution network can no longer adapt to the scenario of coordinated planning of distribution network and microgrid. Summary of the invention

[0004] The technical problem to be solved by the present invention is how to achieve the optimal configuration of the distribution network and the microgrid, and to provide a method and system for collaborative planning, operation and scheduling of the distribution network and the microgrid, which can tap the demand response capability of flexible resources, improve the economic efficiency of investment, and achieve the optimal configuration of the distribution network and the microgrid.

[0005] In order to solve the above technical problems, an embodiment of the present invention provides a method for collaborative planning, operation and scheduling of a distribution network and a microgrid, comprising:

[0006] Acquire historical operation data of the distribution network and the microgrid, and obtain typical scenario characteristics according to the historical operation data; the typical scenario characteristics include typical power characteristics;

[0007] According to the typical scenario characteristics and the preset grid coordinated operation requirements, constraint conditions and objective functions are established to obtain a coordinated planning and operation model of the distribution network and the microgrid; the coordinated planning and operation model includes a grid planning layer and a grid operation layer;

[0008] Performing linear transformation on the collaborative planning and operation model, solving the linearized collaborative planning and operation model, and obtaining configuration and scheduling strategies;

[0009] The configuration and dispatching strategies are applied to configure and dispatch the distribution network and microgrid.

[0010] As an improvement of the above solution, the acquisition of historical operation data of the distribution network and the microgrid, and obtaining typical scenario characteristics according to the historical operation data, include:

[0011] Obtain historical operation data of distribution networks and microgrids;

[0012] Based on the historical operation data, a multi-scenario method is used to obtain several actual operation scenarios;

[0013] Perform K-means clustering on the actual operation scenarios to obtain typical scenarios;

[0014] The typical power feature of each typical scene is calculated as a typical scene feature.

[0015] As an improvement of the above scheme, according to the typical scenario characteristics and the preset grid coordinated operation requirements, constraint conditions and objective functions are established to obtain a coordinated planning and operation model of the distribution network and the microgrid, including:

[0016] According to the typical scenario characteristics and the preset grid coordinated operation requirements, the investment cost and coordinated operation cost of the grid planning under each typical scenario are obtained as the total cost;

[0017] Establishing a first objective function and a preset first constraint condition with the minimum total cost to obtain a power grid planning layer;

[0018] Based on the power grid planning layer, a second objective function and a second constraint condition for minimizing the collaborative operation cost are established to obtain a power grid operation layer;

[0019] A coordinated planning and operation model of the distribution network and the microgrid is obtained according to the grid planning layer and the grid operation layer.

[0020] As an improvement of the above scheme, according to the typical scenario characteristics and the preset grid coordinated operation requirements, the investment cost and coordinated operation cost of the grid planning under each typical scenario are obtained as the total cost, including:

[0021] According to the preset grid coordinated operation requirements, annual values ​​of line investment costs, annual values ​​of microgrid distributed power generation equipment investment costs, and annual values ​​of microgrid energy storage equipment investment costs are obtained to calculate the investment cost of grid planning;

[0022] According to the characteristics of the typical scenario and the preset grid coordinated operation requirements, the power purchase cost of the upper grid based on the typical scenario, the operating cost of the distributed power generation equipment of the microgrid, the energy storage operating cost and the demand response subsidy cost are obtained, and the coordinated operation cost is calculated;

[0023] The investment cost of the power grid planning and the coordinated operation cost are summed to obtain the total cost.

[0024] As an improvement of the above scheme, according to the preset grid coordinated operation requirements, the annual values ​​of line investment costs, the annual values ​​of microgrid distributed power generation equipment investment costs, and the annual values ​​of microgrid energy storage equipment investment costs are obtained to calculate the investment cost of grid planning, including:

[0025] Calculate the annual value of line investment cost based on the full life cycle, fixed construction cost and installation cost of the new line in the preset grid coordinated operation requirements;

[0026] According to the full life cycle, fixed construction cost and installed capacity installation cost of the distributed power generation equipment in the preset grid coordinated operation requirements, the annual value of the investment cost of the microgrid distributed power generation equipment is calculated; the distributed power generation equipment includes photovoltaic equipment, wind power equipment and micro gas turbine equipment;

[0027] Calculate the annual value of the investment cost of microgrid energy storage equipment based on the full life cycle, fixed construction cost and installed capacity cost of the microgrid energy storage equipment in the preset grid coordinated operation requirements;

[0028] The investment cost of the power grid planning is obtained according to the annual values ​​of the line investment cost, the annual values ​​of the microgrid distributed power generation equipment investment cost and the annual values ​​of the microgrid energy storage equipment investment cost.

[0029] As an improvement of the above scheme, according to the typical scenario characteristics and the preset grid coordinated operation requirements, the upper grid power purchase cost based on the typical scenario, the distributed power generation equipment operation cost of the microgrid, the energy storage operation cost and the demand response subsidy cost are obtained, and the coordinated operation cost is calculated, including:

[0030] Calculate the electricity purchase cost of the upper power grid according to the time-of-use electricity price corresponding to each typical scenario and the typical power characteristics;

[0031] Calculate the operating cost of the distributed generation equipment of the microgrid based on the installed capacity and installation cost of the distributed generation equipment in the preset grid coordinated operation requirements;

[0032] Calculating the energy storage operation cost of the microgrid based on the typical power characteristics of the energy storage device of the microgrid;

[0033] According to the typical power characteristics, the required power of the microgrid is obtained, and the demand response subsidy cost of the microgrid is calculated;

[0034] The collaborative operation cost is calculated based on the power purchase cost of the upper-level power grid, the operating cost of the distributed power generation equipment of the microgrid, the energy storage operating cost of the microgrid and the demand response subsidy cost of the microgrid.

[0035] As an improvement of the above solution, the first objective function for minimizing the total cost and the first preset constraint condition are established to obtain the power grid planning layer, including:

[0036] According to the total cost, a first objective function is established, wherein the first objective function minimizes the total cost;

[0037] Establishing a first constraint condition based on network connectivity and open-loop operation constraints, microgrid device capacity constraints, and distribution network installed capacity constraints;

[0038] A power grid planning layer is obtained according to the first objective function and the first constraint condition.

[0039] As an improvement of the above solution, the second objective function and the second constraint condition for minimizing the collaborative operation cost are established based on the power grid planning layer to obtain the power grid operation layer, including:

[0040] In the power grid planning layer, a second objective function is established to minimize the collaborative operation cost;

[0041] According to the grid planning layer, power flow balance constraints, node voltage constraints, branch current constraints, line current carrying capacity constraints, distribution network energy storage operation constraints, transaction power constraints, microgrid energy storage device operation constraints and microgrid demand response operation constraints are obtained as second constraints;

[0042] A power grid operation layer is obtained according to the second objective function and the second constraint condition.

[0043] As an improvement of the above solution, the coordinated planning and operation model of the distribution network and the microgrid is obtained according to the grid planning layer and the grid operation layer, including:

[0044] According to the grid planning layer and the grid operation layer, the coordinated planning and operation model of the distribution network and the microgrid is expressed in matrix form, and the

[0045] Among them, x is the first decision variable of the power grid planning layer; y is the second decision variable of the power grid operation layer; formula (a) is the first constraint condition; formulas (b) to (d) are the representations of the power grid operation layer; CO(y,x) is the collaborative operation cost; formula (c) is the inequality constraint in the second constraint condition; formula (d) is the equality constraint in the second constraint condition.

[0046] As an improvement of the above solution, the collaborative planning operation model is linearized and the linearized collaborative planning operation model is solved to obtain the configuration and scheduling strategy, including:

[0047] The quadratic term in the collaborative planning operation model is approximated by a piecewise function method to obtain the first collaborative planning operation model;

[0048] The first collaborative planning operation model is equivalent to the KKT condition, and the first collaborative planning operation model is linearized by the big M method to obtain the linearized second collaborative planning operation model.

[0049] Among them, x is the decision variable of the power grid planning layer, y is the decision variable of the power grid operation layer; γ and ν are the dual variables of the equation constraint and inequality constraint in the second constraint condition; M is a large constant; I is a 0-1 variable;

[0050] The second collaborative planning operation model is solved to obtain configuration and scheduling strategies.

[0051] The embodiment of the present invention further provides a coordinated planning, operation and scheduling system for a distribution network and a microgrid, including:

[0052] A typical scenario feature generation module is used to obtain historical operation data of the distribution network and the microgrid, and obtain typical scenario features according to the historical operation data; the typical scenario features include typical power features;

[0053] A collaborative planning and operation model establishment module is used to establish constraint conditions and objective functions according to the typical scenario characteristics and preset grid collaborative operation requirements, and obtain a collaborative planning and operation model of the distribution network and the microgrid; the collaborative planning and operation model includes a grid planning layer and a grid operation layer;

[0054] A scheduling strategy generation module is used to perform linear transformation on the collaborative planning operation model, solve the linearized collaborative planning operation model, and obtain configuration and scheduling strategies;

[0055] The power grid configuration and dispatching module is used to apply the configuration and dispatching strategies to configure and dispatch the distribution network and microgrid.

[0056] Compared with the prior art, the present invention discloses a method and system for collaborative planning, operation and scheduling of distribution network and microgrid, which obtains the historical operation data of distribution network and microgrid, and obtains the typical scenario characteristics according to the historical operation data; the typical scenario characteristics include typical power characteristics; according to the typical scenario characteristics and the preset grid collaborative operation requirements, constraint conditions and objective functions are established to obtain the collaborative planning and operation model of distribution network and microgrid; the collaborative planning and operation model includes grid planning layer and grid operation layer; the collaborative planning and operation model is linearized, and the linearized collaborative planning and operation model is solved to obtain the configuration and scheduling strategy; the configuration and scheduling strategy is applied to configure and schedule the distribution network and microgrid. The embodiment of the present invention can tap the demand response capability of flexible resources, improve the economic efficiency of investment, achieve the optimal configuration of distribution network and microgrid, and also have strong security. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 It is a schematic diagram of the steps of a method for collaborative planning, operation and scheduling of a distribution network and a microgrid provided by an embodiment of the present invention;

[0058] Figure 2 It is a structural diagram of a coordinated planning, operation and scheduling system for a distribution network and a microgrid provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0059] 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 only 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 are within the scope of protection of the present invention.

[0060] In the description of the specification and claims, it is to be understood that the terms first, second, etc. in the specification and claims are only used for the purpose of describing the same technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated, nor necessarily describing the order or time sequence. The terms are interchangeable where appropriate. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0061] The embodiment of the present invention provides a method for collaborative planning, operation and scheduling of a distribution network and a microgrid. Figure 1 In this embodiment, the coordinated planning and operation scheduling method of the distribution network and the microgrid is specifically performed through steps S1 to S4:

[0062] S1. Obtain historical operation data of the distribution network and the microgrid, and obtain typical scenario characteristics based on the historical operation data; the typical scenario characteristics include typical power characteristics.

[0063] It should be noted that it is necessary to take into account the grid structure of the distribution network, the load of each node and the grid-connected location of the microgrid, and collect basic data such as typical load characteristics, distributed power supply output characteristics, electricity prices, etc. based on the structure of the distribution network and microgrid as historical operation data.

[0064] In the embodiment of the present invention, by considering the randomness of photovoltaic output, wind turbine output and load demand, the typical scenario characteristics generated avoid the unknown risks brought by source-load uncertainty to the distribution network.

[0065] S2. According to the typical scenario characteristics and the preset grid coordinated operation requirements, constraint conditions and objective functions are established to obtain a coordinated planning and operation model of the distribution network and the microgrid; the coordinated planning and operation model includes a grid planning layer and a grid operation layer.

[0066] S3. Linearize the collaborative planning and operation model, solve the linearized collaborative planning and operation model, and obtain configuration and scheduling strategies.

[0067] The collaborative planning and operation model obtained in the embodiment of the present invention is a two-layer problem. Linearizing the collaborative planning and operation model before solving it can simplify the solution process and better analyze the stability of the power grid.

[0068] S4. Apply the configuration and dispatch strategy to configure and dispatch the distribution network and microgrid.

[0069] As a preferred implementation, step S1, obtaining historical operation data of the distribution network and the microgrid, and obtaining typical scenario features according to the historical operation data, includes:

[0070] Obtain historical operation data of distribution networks and microgrids;

[0071] Based on the historical operation data, a multi-scenario method is used to obtain several actual operation scenarios;

[0072] Perform K-means clustering on the actual operation scenarios to obtain typical scenarios;

[0073] The typical power feature of each typical scene is calculated as a typical scene feature.

[0074] Exemplarily, the present invention adopts a multi-scenario method to obtain N actual operation scenarios through historical operation data, and obtains typical output characteristics of S distributed photovoltaics, wind turbines, and loads and the probability of occurrence of each typical scenario based on K-means clustering.

[0075] As a preferred implementation, step S2, according to the typical scenario characteristics and the preset grid coordinated operation requirements, establish constraints and objective functions, obtain the coordinated planning and operation model of the distribution network and the microgrid, and execute through steps S21 to S24:

[0076] S21. According to the typical scenario characteristics and the preset grid coordinated operation requirements, the investment cost and coordinated operation cost of the grid planning under each typical scenario are obtained as the total cost;

[0077] S22, establishing a first objective function with the minimum total cost and a preset first constraint condition to obtain a power grid planning layer;

[0078] S23. Based on the power grid planning layer, establish a second objective function and a second constraint condition for minimizing the collaborative operation cost to obtain a power grid operation layer;

[0079] S24. Obtain a coordinated planning and operation model of the distribution network and the microgrid according to the grid planning layer and the grid operation layer.

[0080] Further, preferably, step S21, according to the typical scenario characteristics and the preset grid coordinated operation requirements, obtain the investment cost and coordinated operation cost of the grid planning in each typical scenario as the total cost, including:

[0081] According to the preset grid coordinated operation requirements, annual values ​​of line investment costs, annual values ​​of microgrid distributed power generation equipment investment costs, and annual values ​​of microgrid energy storage equipment investment costs are obtained to calculate the investment cost of grid planning;

[0082] According to the characteristics of the typical scenario and the preset grid coordinated operation requirements, the power purchase cost of the upper grid based on the typical scenario, the operating cost of the distributed power generation equipment of the microgrid, the energy storage operating cost and the demand response subsidy cost are obtained, and the coordinated operation cost is calculated;

[0083] The investment cost of the power grid planning and the coordinated operation cost are summed to obtain the total cost.

[0084] It should be noted that, in the embodiment of the present invention, the microgrid distributed power generation equipment includes photovoltaic equipment, wind power equipment and micro gas turbine equipment as an example, but in actual applications, the distributed power generation equipment in the microgrid may also include other equipment, and the important equipment of each microgrid in the power grid needs to be considered during calculation to obtain an accurate scheduling strategy.

[0085] Furthermore, preferably, the method of obtaining annual values ​​of line investment costs, annual values ​​of microgrid distributed power generation equipment investment costs, and annual values ​​of microgrid energy storage equipment investment costs according to the preset grid coordinated operation requirements, and calculating the investment cost of grid planning includes:

[0086] Calculate the annual value of line investment cost based on the full life cycle, fixed construction cost and installation cost of the new line in the preset grid coordinated operation requirements;

[0087] According to the full life cycle, fixed construction cost and installed capacity installation cost of the distributed power generation equipment in the preset grid coordinated operation requirements, the annual value of the investment cost of the microgrid distributed power generation equipment is calculated; the distributed power generation equipment includes photovoltaic equipment, wind power equipment and micro gas turbine equipment;

[0088] Calculate the annual value of the investment cost of microgrid energy storage equipment based on the full life cycle, fixed construction cost and installed capacity cost of the microgrid energy storage equipment in the preset grid coordinated operation requirements;

[0089] The investment cost of the power grid planning is obtained according to the annual values ​​of the line investment cost, the annual values ​​of the microgrid distributed power generation equipment investment cost and the annual values ​​of the microgrid energy storage equipment investment cost.

[0090] For example, by The annual value of the line investment cost is obtained; where a is the discount rate; l line is the full life cycle of the line; when the road between node i and node j is a new line, x line,ij is 1, otherwise it is 0; Fixed construction cost for new lines; c line is the installation cost per unit length of line; L ij is the length of the road between node i and node j;

[0091] pass The annual value of the investment cost of the microgrid distributed generation equipment of the mth microgrid is obtained; where l PV , l WT and l MT They are the full life cycle of photovoltaic equipment, wind power equipment and steam turbine equipment respectively; and are the fixed construction costs of photovoltaic equipment, wind power equipment and steam turbine equipment respectively; c PV 、c WT and c MT are the unit capacity installation costs of photovoltaic equipment, wind power equipment and steam turbine equipment respectively; S PV,m , S WT,m and S MT,m They are the installed capacities of photovoltaic equipment, wind power equipment and steam turbine equipment respectively;

[0092] pass Get the annual value of the microgrid energy storage ESS investment cost of the mth microgrid; where l ESSFor the entire life cycle of ESS; is the fixed construction cost of ESS; c ESS is the installation cost per unit capacity of ESS; S ESS,m is the installed capacity of ESS in the mth microgrid;

[0093] pass Get the investment cost of power grid planning.

[0094] As a preferred implementation, according to the typical scenario characteristics and the preset grid coordinated operation requirements, the upper grid power purchase cost based on the typical scenario, the distributed power generation equipment operation cost of the microgrid, the energy storage operation cost and the demand response subsidy cost are obtained, and the coordinated operation cost is calculated, including:

[0095] Calculate the electricity purchase cost of the upper power grid according to the time-of-use electricity price corresponding to each typical scenario and the typical power characteristics;

[0096] Calculate the operating cost of the distributed generation equipment of the microgrid based on the installed capacity and installation cost of the distributed generation equipment in the preset grid coordinated operation requirements;

[0097] Calculating the energy storage operation cost of the microgrid based on the typical power characteristics of the energy storage device of the microgrid;

[0098] According to the typical power characteristics, the required power of the microgrid is obtained, and the demand response subsidy cost of the microgrid is calculated;

[0099] The collaborative operation cost is calculated based on the power purchase cost of the upper-level power grid, the operating cost of the distributed power generation equipment of the microgrid, the energy storage operating cost of the microgrid and the demand response subsidy cost of the microgrid.

[0100] For example, according to the typical output characteristics and the preset grid coordinated operation requirements, the number of typical scenarios S and the number of days N of the sth typical scenario are obtained. s , the total number of nodes at each time T, the access node set Ω of the upper power grid injection power G , photovoltaic output characteristics of the sth typical scenario Wind power output characteristics of the sth typical scenario Output characteristics of micro gas turbine equipment in the sth typical scenario

[0101] pass Get the power purchase cost of the upper power grid; among them, is the time-of-use electricity price at the tth moment; Δt is the duration of the tth moment; is the active power injected by the upper grid at the jth access node in the sth typical scenario at time t;

[0102] pass

[0103] Get the operating cost of the distributed generation equipment of the mth microgrid; where c PV 、c WT and c MT are the unit capacity installation costs of photovoltaic equipment, wind power equipment and micro gas turbine equipment respectively; S PV,m , S WT,m and S MT,m They are the installed capacity of photovoltaic equipment, wind power equipment and micro gas turbine equipment respectively;

[0104] pass Get the energy storage equipment operating cost of the mth microgrid; where c ESS The operating cost of charging / discharging a unit of electricity for energy storage equipment; is the charging power of the energy storage device of the mth microgrid at the sth typical scenario at time t; is the discharge power of the energy storage device in the mth microgrid at the sth typical scenario at time t;

[0105] pass Get the demand response subsidy cost of the mth microgrid; where k n is the sensitivity coefficient of the microgrid to the nth type of load transfer willingness; is the power demand of the nth type of response load at the mth microgrid in the sth typical scenario at the tth moment; is the original demand of the nth type of response load at the tth moment of the mth microgrid in the sth typical scenario;

[0106] By Get the collaborative operating cost.

[0107] As a preferred implementation, step S22, establishing the first objective function with the minimum total cost and the first preset constraint condition to obtain the power grid planning layer, includes:

[0108] According to the total cost, a first objective function is established, wherein the first objective function minimizes the total cost;

[0109] Establishing a first constraint condition based on network connectivity and open-loop operation constraints, microgrid device capacity constraints, and distribution network installed capacity constraints;

[0110] A power grid planning layer is obtained according to the first objective function and the first constraint condition.

[0111] Exemplarily, the first objective function is minC=CI+CO, wherein CI is the investment cost of the power grid planning; and CO is the coordinated operation cost.

[0112] The capacity constraint of the microgrid device is The installed capacity constraint of the distribution network is Among them, S PVmax,m , S WTmax,m , S MTmax,m and S ESSmax,m are the upper limits of installed capacity of photovoltaic equipment, wind power equipment, micro gas turbine equipment and energy storage equipment in the mth microgrid respectively; P Lmax is the system load peak; η DGmax It is the maximum value of the distributed generation penetration rate in the system.

[0113] As a preferred implementation, step S23, based on the power grid planning layer, establishes the second objective function and the second constraint condition for minimizing the collaborative operation cost to obtain the power grid operation layer, including:

[0114] In the power grid planning layer, a second objective function is established to minimize the collaborative operation cost;

[0115] According to the grid planning layer, power flow balance constraints, node voltage constraints, branch current constraints, line current carrying capacity constraints, distribution network energy storage operation constraints, transaction power constraints, microgrid energy storage device operation constraints and microgrid demand response operation constraints are obtained as second constraints;

[0116] A power grid operation layer is obtained according to the second objective function and the second constraint condition.

[0117] Exemplarily, the second objective function is Among them, CO G The cost of purchasing electricity from the upper power grid; CO DG,m is the operating cost of the distributed generation equipment in the mth microgrid; CO ESS,m is the energy storage operation cost of the mth microgrid; CO DR,m is the demand response subsidy cost of the mth microgrid; M is the total number of microgrids.

[0118] The power flow balance constraints include active power constraints, reactive power constraints, and node quantity constraints between nodes in various typical scenarios.

[0119] The node voltage constraints are Among them, U imin , U imax are the lower and upper voltage limits of node i, respectively. imin Take 0.95, U imax Take 1.05.

[0120] The branch current constraint is Among them, lij,t,s is the current value between node i and node j at time t in the sth typical scenario; I ijmax is the maximum current allowed to flow between node i and node j.

[0121] The line current carrying capacity is constrained to Among them, S ijmax is the maximum apparent power allowed to flow between node i and node j; is the square value of the active power of line ij at time t in the sth typical scenario; is the square value of the active power of line ij at time t in the sth typical scenario; line ij consists of nodes i and j.

[0122] The energy storage operation constraints of the distribution network are: in, and are the upper limits of the allowed charging power and discharging power of the energy storage device at node j on the distribution network side, respectively; is the capacity of energy storage equipment at the node j on the distribution network side at the tth time in the sth typical scenario; η ch and η dch are the energy storage charging efficiency and discharging efficiency respectively; and are the lower and upper limits of the capacity of the energy storage device at node j on the distribution network side, respectively.

[0123] Transaction power constraints include in, is the operation mode of the microgrid m in the sth typical scenario at time t, which is 1 in grid-connected mode and 0 in off-grid mode; is the upper limit of the active power traded between the microgrid m and the distribution network; is the upper limit of reactive power traded between microgrid m and distribution network.

[0124] The operating constraints of the microgrid energy storage device are in, and are the upper limits of the allowed charging power and discharging power of the energy storage device configured for the s-th typical scenario of microgrid m; The capacity of energy storage equipment configured for the sth typical scenario of microgrid m at time t; σ ch and η dch are the energy storage charging efficiency and discharging efficiency respectively; and are the lower and upper limits of the capacity of the energy storage equipment configured for microgrid m respectively.

[0125] The microgrid demand response operation constraints are: in, and are the lower and upper limits of the load demand after the microgrid m demand response, respectively; is the original load demand active power of microgrid m at the tth moment in the sth typical scenario.

[0126] It should be noted that in the second constraint condition described in the embodiment of the present invention, the power flow balance constraint is an equality constraint, while the other constraints are inequality constraints. In the process of establishing and solving the retrograde model, it is necessary to divide the equality constraint and the inequality constraint.

[0127] As a preferred implementation, step S24, obtaining a coordinated planning and operation model of a distribution network and a microgrid according to the grid planning layer and the grid operation layer, includes:

[0128] According to the grid planning layer and the grid operation layer, the coordinated planning and operation model of the distribution network and the microgrid is expressed in matrix form, and the

[0129] Among them, x is the first decision variable of the power grid planning layer; y is the second decision variable of the power grid operation layer; formula (a) is the first constraint condition; formulas (b) to (d) are the representations of the power grid operation layer; CO(y,x) is the collaborative operation cost; formula (c) is the inequality constraint in the second constraint condition; formula (d) is the equality constraint in the second constraint condition.

[0130] On this basis, preferably, step S4, linearizing the collaborative planning and operation model, solving the linearized collaborative planning and operation model, and obtaining a configuration and scheduling strategy, includes:

[0131] The quadratic term in the collaborative planning operation model is approximated by a piecewise function method to obtain the first collaborative planning operation model;

[0132] The first collaborative planning operation model is equivalent to the KKT condition, and the first collaborative planning operation model is linearized by the big M method to obtain the linearized second collaborative planning operation model.

[0133] Among them, x is the decision variable of the power grid planning layer, y is the decision variable of the power grid operation layer; γ and ν are the dual variables of the equation constraint and inequality constraint in the second constraint condition; M is a large constant; I is a 0-1 variable;

[0134] The second collaborative planning operation model is solved to obtain configuration and scheduling strategies.

[0135] Exemplarily, in the embodiment of the present invention, the demand response subsidy cost of the microgrid is a quadratic term, and the piecewise function method is used for approximation. in, is the slope of the kth segment of the equivalent piecewise function; is the intercept of the kth segment of the equivalent piecewise function.

[0136] In some preferred embodiments, the line current carrying capacity constraints are linearized using the equivalent polygon method.

[0137] It should be noted that the linearized second collaborative planning operation model is a MILP problem. Preferably, a linear solver is used to solve the second collaborative planning operation model.

[0138] The coordinated planning, operation and scheduling method for distribution networks and microgrids provided by the embodiment of the present invention can tap the demand response capability of flexible resources, improve the economic efficiency of investment, achieve the optimal configuration of distribution networks and microgrids, and also have strong security.

[0139] The embodiment of the present invention provides a coordinated planning, operation and scheduling system for a distribution network and a microgrid. Figure 2 The distribution network and microgrid collaborative planning and operation scheduling system includes a typical scenario feature generation module 11, a collaborative planning and operation model establishment module 12, a scheduling strategy generation module 13 and a power grid configuration and scheduling module 14, wherein:

[0140] A typical scenario feature generation module 11 is used to obtain historical operation data of the distribution network and the microgrid, and obtain typical scenario features according to the historical operation data; the typical scenario features include typical power features;

[0141] The collaborative planning and operation model establishment module 12 is used to establish constraint conditions and objective functions according to the typical scenario characteristics and the preset grid collaborative operation requirements, and obtain the collaborative planning and operation model of the distribution network and the microgrid; the collaborative planning and operation model includes a grid planning layer and a grid operation layer;

[0142] The scheduling strategy generation module 13 is used to perform linear transformation on the collaborative planning operation model, solve the linearized collaborative planning operation model, and obtain the configuration and scheduling strategy;

[0143] The grid configuration and dispatching module 14 is used to apply the configuration and dispatching strategies to configure and dispatch the distribution network and microgrid.

[0144] As a preferred implementation, the typical scene feature generation module 11 is specifically used for:

[0145] Obtain historical operation data of distribution networks and microgrids;

[0146] Based on the historical operation data, a multi-scenario method is used to obtain several actual operation scenarios;

[0147] Perform K-means clustering on the actual operation scenarios to obtain typical scenarios;

[0148] The typical power feature of each typical scene is calculated as a typical scene feature.

[0149] As a preferred implementation, the collaborative planning operation model building module 12 includes:

[0150] A total cost calculation unit, used to obtain the investment cost and coordinated operation cost of the power grid planning under each typical scenario as the total cost according to the typical scenario characteristics and the preset power grid coordinated operation requirements;

[0151] A power grid planning layer establishing unit, used to establish a first objective function with the minimum total cost and a preset first constraint condition to obtain a power grid planning layer;

[0152] A power grid operation layer establishing unit, used to establish a second objective function and a second constraint condition for minimizing the collaborative operation cost based on the power grid planning layer, to obtain a power grid operation layer;

[0153] A model generation unit is used to obtain a coordinated planning and operation model of the distribution network and the microgrid according to the power grid planning layer and the power grid operation layer.

[0154] Further, preferably, the total cost calculation unit is specifically used to:

[0155] According to the preset grid coordinated operation requirements, annual values ​​of line investment costs, annual values ​​of microgrid distributed power generation equipment investment costs, and annual values ​​of microgrid energy storage equipment investment costs are obtained to calculate the investment cost of grid planning;

[0156] According to the characteristics of the typical scenario and the preset grid coordinated operation requirements, the power purchase cost of the upper grid based on the typical scenario, the operating cost of the distributed power generation equipment of the microgrid, the energy storage operating cost and the demand response subsidy cost are obtained, and the coordinated operation cost is calculated;

[0157] The investment cost of the power grid planning and the coordinated operation cost are summed to obtain the total cost.

[0158] Furthermore, preferably, the method of obtaining annual values ​​of line investment costs, annual values ​​of microgrid distributed power generation equipment investment costs, and annual values ​​of microgrid energy storage equipment investment costs according to the preset grid coordinated operation requirements, and calculating the investment cost of grid planning includes:

[0159] Calculate the annual value of line investment cost based on the full life cycle, fixed construction cost and installation cost of the new line in the preset grid coordinated operation requirements;

[0160] According to the full life cycle, fixed construction cost and installed capacity installation cost of the distributed power generation equipment in the preset grid coordinated operation requirements, the annual value of the investment cost of the microgrid distributed power generation equipment is calculated; the distributed power generation equipment includes photovoltaic equipment, wind power equipment and micro gas turbine equipment;

[0161] Calculate the annual value of the investment cost of microgrid energy storage equipment based on the full life cycle, fixed construction cost and installed capacity cost of the microgrid energy storage equipment in the preset grid coordinated operation requirements;

[0162] The investment cost of the power grid planning is obtained according to the annual values ​​of the line investment cost, the annual values ​​of the microgrid distributed power generation equipment investment cost and the annual values ​​of the microgrid energy storage equipment investment cost.

[0163] Preferably, according to the typical scenario characteristics and the preset grid coordinated operation requirements, the upper grid power purchase cost based on the typical scenario, the distributed power generation equipment operation cost of the microgrid, the energy storage operation cost and the demand response subsidy cost are obtained, and the coordinated operation cost is calculated, including:

[0164] Calculate the electricity purchase cost of the upper power grid according to the time-of-use electricity price corresponding to each typical scenario and the typical power characteristics;

[0165] Calculate the operating cost of the distributed generation equipment of the microgrid based on the installed capacity and installation cost of the distributed generation equipment in the preset grid coordinated operation requirements;

[0166] Calculating the energy storage operation cost of the microgrid based on the typical power characteristics of the energy storage device of the microgrid;

[0167] According to the typical power characteristics, the required power of the microgrid is obtained, and the demand response subsidy cost of the microgrid is calculated;

[0168] The collaborative operation cost is calculated based on the power purchase cost of the upper-level power grid, the operating cost of the distributed power generation equipment of the microgrid, the energy storage operating cost of the microgrid and the demand response subsidy cost of the microgrid.

[0169] As a preferred implementation manner, the power grid planning layer establishing unit is specifically used to:

[0170] According to the total cost, a first objective function is established, wherein the first objective function minimizes the total cost;

[0171] Establishing a first constraint condition based on network connectivity and open-loop operation constraints, microgrid device capacity constraints, and distribution network installed capacity constraints;

[0172] A power grid planning layer is obtained according to the first objective function and the first constraint condition.

[0173] As a preferred implementation manner, the power grid operation layer establishment unit is specifically used to:

[0174] In the power grid planning layer, a second objective function is established to minimize the collaborative operation cost;

[0175] According to the grid planning layer, power flow balance constraints, node voltage constraints, branch current constraints, line current carrying capacity constraints, distribution network energy storage operation constraints, transaction power constraints, microgrid energy storage device operation constraints and microgrid demand response operation constraints are obtained as second constraints;

[0176] A power grid operation layer is obtained according to the second objective function and the second constraint condition.

[0177] As a preferred implementation, the model generation unit is specifically used to:

[0178] According to the grid planning layer and the grid operation layer, the coordinated planning and operation model of the distribution network and the microgrid is expressed in matrix form, and the

[0179] Among them, x is the first decision variable of the power grid planning layer; y is the second decision variable of the power grid operation layer; formula (a) is the first constraint condition; formulas (b) to (d) are the representations of the power grid operation layer; CO(y,x) is the collaborative operation cost; formula (c) is the inequality constraint in the second constraint condition; formula (d) is the equality constraint in the second constraint condition.

[0180] Further, preferably, the configuration and scheduling strategy generation module 13 is specifically used for:

[0181] The quadratic term in the collaborative planning operation model is approximated by a piecewise function method to obtain the first collaborative planning operation model;

[0182] The first collaborative planning operation model is equivalent to the KKT condition, and the first collaborative planning operation model is linearized by the big M method to obtain the linearized second collaborative planning operation model.

[0183] Among them, x is the decision variable of the power grid planning layer, y is the decision variable of the power grid operation layer; γ and v are the dual variables of the equation constraint and inequality constraint in the second constraint condition; M is a large constant; I is a 0-1 variable;

[0184] The second collaborative planning operation model is solved to obtain configuration and scheduling strategies.

[0185] A coordinated planning, operation and dispatching system for a distribution network and a microgrid provided by an embodiment of the present invention can tap the demand response capability of flexible resources, improve the economic efficiency of investment, achieve the optimal configuration of the distribution network and the microgrid, and also have strong security.

[0186] A person skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium, and when the program is executed, it can include the processes of the embodiments of the above-mentioned methods. The storage medium can be a disk, an optical disk, a read-only memory (ROM) or a random access memory (RAM), etc.

[0187] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A method for collaborative planning, operation and scheduling of a distribution network and a microgrid, characterized in that: include: Acquire historical operation data of the distribution network and the microgrid, and obtain typical scenario characteristics based on the historical operation data; The typical scene characteristics include typical power characteristics; According to the typical scenario characteristics and the preset grid coordinated operation requirements, constraint conditions and objective functions are established to obtain a coordinated planning and operation model of the distribution network and the microgrid; the coordinated planning and operation model includes a grid planning layer and a grid operation layer; Performing linear transformation on the collaborative planning and operation model, solving the linearized collaborative planning and operation model, and obtaining configuration and scheduling strategies; The configuration and dispatching strategies are applied to configure and dispatch the distribution network and microgrid.

2. A method for collaborative planning, operation and scheduling of a distribution network and a microgrid as claimed in claim 1, characterized in that: The acquiring of historical operation data of the distribution network and the microgrid, and obtaining typical scenario characteristics according to the historical operation data, includes: Obtain historical operation data of distribution networks and microgrids; Based on the historical operation data, a multi-scenario method is used to obtain several actual operation scenarios; Perform K-means clustering on the actual operation scenarios to obtain typical scenarios; The typical power feature of each typical scene is calculated as a typical scene feature.

3. A method for collaborative planning, operation and scheduling of a distribution network and a microgrid as claimed in claim 1, characterized in that: According to the typical scenario characteristics and the preset grid coordinated operation requirements, constraint conditions and objective functions are established to obtain a coordinated planning and operation model of the distribution network and the microgrid, including: According to the typical scenario characteristics and the preset grid coordinated operation requirements, the investment cost and coordinated operation cost of the grid planning under each typical scenario are obtained as the total cost; Establishing a first objective function and a preset first constraint condition with the minimum total cost to obtain a power grid planning layer; Based on the power grid planning layer, a second objective function and a second constraint condition for minimizing the collaborative operation cost are established to obtain a power grid operation layer; A coordinated planning and operation model of the distribution network and the microgrid is obtained according to the grid planning layer and the grid operation layer.

4. A method for collaborative planning, operation and scheduling of a distribution network and a microgrid as claimed in claim 3, characterized in that: According to the typical scenario characteristics and the preset grid coordinated operation requirements, the investment cost and coordinated operation cost of the grid planning under each typical scenario are obtained as the total cost, including: According to the preset grid coordinated operation requirements, annual values ​​of line investment costs, annual values ​​of microgrid distributed power generation equipment investment costs, and annual values ​​of microgrid energy storage equipment investment costs are obtained to calculate the investment cost of grid planning; According to the characteristics of the typical scenario and the preset grid coordinated operation requirements, the power purchase cost of the upper grid based on the typical scenario, the operating cost of the distributed power generation equipment of the microgrid, the energy storage operating cost and the demand response subsidy cost are obtained, and the coordinated operation cost is calculated; The investment cost of the power grid planning and the coordinated operation cost are summed to obtain the total cost.

5. A method for collaborative planning, operation and scheduling of a distribution network and a microgrid as claimed in claim 4, characterized in that: The method of obtaining annual values ​​of line investment costs, annual values ​​of microgrid distributed power generation equipment investment costs, and annual values ​​of microgrid energy storage equipment investment costs based on the preset grid coordinated operation requirements, and calculating the investment cost of grid planning includes: Calculate the annual value of line investment cost based on the full life cycle, fixed construction cost and installation cost of the new line in the preset grid coordinated operation requirements; According to the full life cycle, fixed construction cost and installed capacity installation cost of the distributed power generation equipment in the preset grid coordinated operation requirements, the annual value of the investment cost of the microgrid distributed power generation equipment is calculated; the distributed power generation equipment includes photovoltaic equipment, wind power equipment and micro gas turbine equipment; Calculate the annual value of the investment cost of microgrid energy storage equipment based on the full life cycle, fixed construction cost and installed capacity cost of the microgrid energy storage equipment in the preset grid coordinated operation requirements; The investment cost of the power grid planning is obtained according to the annual values ​​of the line investment cost, the annual values ​​of the microgrid distributed power generation equipment investment cost and the annual values ​​of the microgrid energy storage equipment investment cost.

6. A method for collaborative planning, operation and scheduling of a distribution network and a microgrid as claimed in claim 4, characterized in that: According to the typical scenario characteristics and the preset grid coordinated operation requirements, the upper grid power purchase cost based on the typical scenario, the distributed power generation equipment operation cost of the microgrid, the energy storage operation cost and the demand response subsidy cost are obtained, and the coordinated operation cost is calculated, including: Calculate the electricity purchase cost of the upper power grid according to the time-of-use electricity price corresponding to each typical scenario and the typical power characteristics; Calculate the operating cost of the distributed generation equipment of the microgrid based on the installed capacity and installation cost of the distributed generation equipment in the preset grid coordinated operation requirements; Calculating the energy storage operation cost of the microgrid based on the typical power characteristics of the energy storage device of the microgrid; According to the typical power characteristics, the required power of the microgrid is obtained, and the demand response subsidy cost of the microgrid is calculated; The collaborative operation cost is calculated based on the power purchase cost of the upper-level power grid, the operating cost of the distributed power generation equipment of the microgrid, the energy storage operating cost of the microgrid and the demand response subsidy cost of the microgrid.

7. A method for collaborative planning, operation and scheduling of a distribution network and a microgrid as claimed in claim 3, characterized in that: The step of establishing the first objective function and the first preset constraint condition with the minimum total cost to obtain the power grid planning layer includes: According to the total cost, a first objective function is established, wherein the first objective function minimizes the total cost; Establishing a first constraint condition based on network connectivity and open-loop operation constraints, microgrid device capacity constraints, and distribution network installed capacity constraints; A power grid planning layer is obtained according to the first objective function and the first constraint condition.

8. A method for collaborative planning, operation and scheduling of a distribution network and a microgrid as claimed in claim 3, characterized in that: The second objective function and the second constraint condition for minimizing the collaborative operation cost are established based on the power grid planning layer to obtain the power grid operation layer, including: In the power grid planning layer, a second objective function is established to minimize the collaborative operation cost; According to the grid planning layer, power flow balance constraints, node voltage constraints, branch current constraints, line current carrying capacity constraints, distribution network energy storage operation constraints, transaction power constraints, microgrid energy storage device operation constraints and microgrid demand response operation constraints are obtained as second constraints; A power grid operation layer is obtained according to the second objective function and the second constraint condition.

9. A method for collaborative planning, operation and scheduling of a distribution network and a microgrid as claimed in claim 3, characterized in that: The collaborative planning and operation model of the distribution network and the microgrid is obtained according to the grid planning layer and the grid operation layer, including: According to the grid planning layer and the grid operation layer, the coordinated planning and operation model of the distribution network and the microgrid is expressed in matrix form, and the Among them, x is the first decision variable of the power grid planning layer; y is the second decision variable of the power grid operation layer; formula (a) is the first constraint condition; formulas (b) to (d) are the representations of the power grid operation layer; CO(y,x) is the collaborative operation cost; formula (c) is the inequality constraint in the second constraint condition; formula (d) is the equality constraint in the second constraint condition.

10. A method for collaborative planning, operation and scheduling of a distribution network and a microgrid as claimed in claim 9, characterized in that: The linearizing the collaborative planning operation model, solving the linearized collaborative planning operation model, and obtaining the configuration and scheduling strategy include: The quadratic term in the collaborative planning operation model is approximated by a piecewise function method to obtain the first collaborative planning operation model; The first collaborative planning operation model is equivalent to the KKT condition, and the first collaborative planning operation model is linearized by the big M method to obtain the linearized second collaborative planning operation model. Among them, x is the decision variable of the power grid planning layer, y is the decision variable of the power grid operation layer; γ and v are the dual variables of the equation constraint and inequality constraint in the second constraint condition; M is a large constant; I is a 0-1 variable; The second collaborative planning operation model is solved to obtain configuration and scheduling strategies.

11. A coordinated planning, operation and dispatching system for distribution network and microgrid, characterized in that: include: A typical scenario feature generation module is used to obtain historical operation data of the distribution network and the microgrid, and obtain typical scenario features according to the historical operation data; The typical scene characteristics include typical power characteristics; A collaborative planning and operation model establishment module is used to establish constraint conditions and objective functions according to the typical scenario characteristics and the preset grid collaborative operation requirements, and obtain a collaborative planning and operation model of the distribution network and the microgrid; the collaborative planning and operation model includes a grid planning layer and a grid operation layer; A scheduling strategy generation module is used to perform linear transformation on the collaborative planning operation model, solve the linearized collaborative planning operation model, and obtain configuration and scheduling strategies; The power grid configuration and dispatching module is used to apply the configuration and dispatching strategies to configure and dispatch the distribution network and microgrid.

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