Mobile energy storage scheduling method and system and readable storage medium

Abstract

The invention provides a mobile energy storage scheduling method and system and a readable storage medium, and the method comprises the steps: obtaining the node distance between any two nodes in a target power distribution network and the node time consumed when mobile energy storage moves to the space between any two nodes, respectively constructing a distance matrix and a time matrix according to the node distance and the node time; assuming that an equivalent switch exists between the mobile energy storage and accessible nodes thereof, and constructing a scheduling equivalent scheme of the mobile energy storage; obtaining the total revenue of the operator according to the distance matrix and the time matrix, and constructing a target function by taking the maximization of the total revenue of the operator as a target; constructing constraint conditions of the target function, wherein the constraint conditions comprise a power distribution network operation constraint, a renewable energy output constraint and a mobile energy storage operation constraint; and solving the objective function to obtain an optimal scheduling planning scheme of mobile energy storage. According to the invention, the optimal scheduling planning scheme of mobile energy storage can be obtained, so that the economic benefit of a power distribution network operator is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of mobile energy storage scheduling, and in particular to a scheduling method, system and readable storage medium for mobile energy storage. Background Art

[0002] With the large-scale access and increasing penetration of renewable energy, the randomness, intermittency and volatility of its output limit the absorption capacity of the distribution network. Mobile energy storage can solve the problems of wind and solar abandonment, voltage over-limit and insufficient peak-shaving capacity of the distribution network with its flexible energy management and rapid power regulation capabilities. The rational use of mobile energy storage is of great significance to the efficient operation of the distribution network.

[0003] Mobile energy storage has been used in many practical projects, such as emergency response, grid resilience improvement, and grid voltage stabilization, and has certain theoretical support. However, current research shows that few studies have analyzed its operating mechanism in typical application scenarios, and there is a lack of corresponding principle explanations, so that it is impossible to accurately judge the role and advantages of mobile energy storage in actual application scenarios; and at the research level, current research on mobile energy storage mostly stays on emergency response, grid resilience improvement, grid voltage stabilization and other stability issues. Few studies have proposed the use of mobile energy storage in distribution networks to improve the absorption of new energy and the economy of distribution networks, and there is a lack of corresponding feasible plans as support. Summary of the invention

[0004] The purpose of the present invention is to provide a scheduling method, system and readable storage medium for mobile energy storage, aiming to solve the problems of large-scale renewable energy access and difficulty in scheduling and controlling mobile energy storage in the future, and to simplify the complex mobile energy storage scheduling process through the optimization means of equivalent transformation, so as to achieve its economic advantages in improving the new energy consumption rate and increasing the operator's profits.

[0005] In a first aspect, the present invention provides a method for dispatching mobile energy storage, the method comprising:

[0006] Obtain the node distance between any two nodes in the target distribution network and the node time consumed by the mobile energy storage to move between any two nodes, so as to construct a distance matrix and a time matrix according to the node distance and the node time respectively;

[0007] Assume that there is an equivalent switch between the mobile energy storage and its accessible nodes, and construct an equivalent scheduling scheme for the mobile energy storage;

[0008] Obtaining the total revenue of the operator according to the distance matrix and the time matrix, and constructing an objective function with the goal of maximizing the total revenue of the operator;

[0009] Constructing constraint conditions of the objective function, wherein the constraint conditions include distribution network operation constraints, renewable energy output constraints, and mobile energy storage operation constraints;

[0010] The objective function is solved to obtain the optimal scheduling planning scheme for mobile energy storage.

[0011] Furthermore, the step of obtaining the node distance between any two nodes in the target distribution network and the node time consumed by the mobile energy storage to move between any two nodes, and constructing a distance matrix and a time matrix according to the node distance and the node time respectively includes:

[0012] The distance matrix is ​​constructed according to the following formula:

[0013]

[0014] The time matrix is ​​constructed according to the following formula:

[0015]

[0016] Among them, D m,n,t Represents the total distance moved by the mobile energy storage, D 1,M and D M,1 Both represent the distance from the 1st node to the Mth node or from the Mth node to the 1st node, T m,n,t represents the time matrix, T 1,M and T M,1 Both represent the time consumed by the mobile energy storage from the 1st node to the Mth node or from the Mth node to the 1st node, T m,n,t Represents the total moving time of mobile energy storage.

[0017] Furthermore, the step of assuming that there is an equivalent switch between the mobile energy storage and its accessible nodes and constructing an equivalent scheduling scheme for the mobile energy storage includes:

[0018] If the mobile energy storage needs to be moved to a certain node to supply power, it is considered that there is an equivalent switch between the mobile energy storage and this node;

[0019] When the mobile energy storage moves to this node, the corresponding equivalent switch is closed, and when it is not at this node, the corresponding equivalent switch is in the open state;

[0020] The dispatch equivalent scheme of mobile energy storage is constructed according to the following formula:

[0021]

[0022] Among them, S l,t is a binary variable, indicating the on / off state of the lth equivalent switch at time t; X m,n,t , X m,n,t-1 are binary variables, representing the time at t, t+σ m,n,t-1 Time, t+σ m,n,t At time t, at time t-1, whether the mth switch is open and the nth switch is closed; t+σ m,n,t , t+σ m,n,t-1 Respectively represent the switching time from m to n at time t and time t-1; α l,t , α n,t Both are binary variables, indicating whether the lth and nth equivalent switches are switched from the open state to the closed state at time t; β l,t , β m,t are binary variables, indicating whether the lth and mth equivalent switches are switched from the closed state to the open state at time t; S l,t-1 It represents the on / off state of the lth equivalent switch at time t-1; it is a binary variable, indicating whether the mth equivalent switch switches from the closed state to the open state at time t.

[0023] Furthermore, the step of obtaining the total revenue of the operator according to the distance matrix and the time matrix and constructing an objective function with the goal of maximizing the total revenue of the operator includes:

[0024] The objective function is constructed according to the following formula:

[0025]

[0026] Among them, C all is the total revenue of the operator, and the goal is to maximize the total revenue. sell,use is the operator’s electricity sales revenue, C buy,grid is the operator’s upper-level electricity purchase cost, C loss,power is the cost of curtailing wind and solar power, C switch The total cost of mobile energy storage equivalent to the switch;

[0027] The total cost of mobile energy storage equivalent to a switch is calculated according to the following formula:

[0028] C switch =C invest +C repair +C toggle

[0029] Among them, C invest represents the investment cost, C repair represents the maintenance cost, C toggle represents the switching cost;

[0030] The cost of curtailing wind and solar power is calculated using the following formula:

[0031]

[0032] The operator's electricity sales revenue is calculated according to the following formula:

[0033] C sell,use =(τ·P load,i,t SP t )

[0034] The operator's upper-level electricity purchase cost is calculated according to the following formula:

[0035] C buy,grid =(τ·PP t ·P grid,t )

[0036] Among them, η RDG Penalty costs for curtailing wind and solar power; is the abandoned wind and solar power of photovoltaic and wind power generation at node i at time t; τ is the time step; P load,i,t is the active power of the load of node i at time t; SP t is the electricity price at time t; P grid,t is the active power PP from the upper power purchasing grid at time t t is the electricity purchase price at time t.

[0037] Furthermore, the investment cost is calculated according to the following formula:

[0038] C invest =L mess ·E mess ·μ

[0039] The maintenance cost is calculated according to the following formula:

[0040] C repair =G mess ·E mess

[0041] The switching cost of the equivalent switch is calculated according to the following formula:

[0042]

[0043] Among them, L mess E is the investment cost per unit capacity of mobile energy storage; mess is the rated capacity of mobile energy storage; μ is the loss rate; G mess is the maintenance cost per unit capacity of mobile energy storage; C path D is the cost per kilometer of mobile energy storage; m,n,t is the total moving distance of the mobile energy storage; X m,n,tis a binary variable, indicating whether the mth switch is open and the nth switch is closed at time t.

[0044] Furthermore, the step of constructing the constraint conditions of the objective function, wherein the constraint conditions include distribution network operation constraints, renewable energy output constraints, and mobile energy storage operation constraints, includes:

[0045] The distribution network operation constraints are constructed according to the following formula:

[0046]

[0047] I i,j,t ≤I i,j,max

[0048] U min ≤U i,t ≤U max

[0049] Among them, P RDG,i,t , Q RDG,i,t are respectively the active power and reactive power actually consumed by the photovoltaic and wind power generation at node i at time t, P mess,l,t , Q mess,l,t are the active power and reactive power generated by the mobile energy storage connected to the lth access point at time t, P i,j,t , Q i,j,t are respectively the active power and reactive power of the ij branch at time t; r k,i 、x k,i 、r i,j 、x i,j They are ki branch resistance, ki branch reactance, ij branch resistance, ij branch reactance, I k,i,t is the effective value of the current at branch ki at time t; U i,t is the effective value of the voltage at node i at time t; I i,j,max is the maximum current that branch ij can withstand; U min , U max The minimum and maximum voltage limits for each node; P load,i,t represents the active power of the load at node i at time t, P k,i,t represents the active power of branch ki at time t; Q load,i,t represents the reactive power of the load at node i at time t, Q k,i,t represents the reactive power of branch ki at time t, I i,j,t It represents the effective value of the current at branch ij at time t;

[0050] Furthermore, the step of constructing the constraint conditions of the objective function, wherein the constraint conditions include distribution network operation constraints, renewable energy output constraints, and mobile energy storage operation constraints, includes:

[0051] The renewable energy output constraint is constructed according to the following formula:

[0052]

[0053] in, represents the real value of active power generated by photovoltaic and wind power generation at node i at time t, It represents the abandoned wind and solar power of photovoltaic and wind power generation at node i at time t.

[0054] Furthermore, the step of constructing the constraint conditions of the objective function, wherein the constraint conditions include distribution network operation constraints, renewable energy output constraints, and mobile energy storage operation constraints, includes:

[0055] The mobile energy storage operation constraints are constructed according to the following formula:

[0056] P mess,l,t =P ch,l,t +P dis,l,t

[0057] 0≤P ch,l,t ≤P mess,max ·S ch,l,t

[0058] -P mess,max ·S dis,l,t ≤P dis,l,t ≤0

[0059] S ch,l,t +S dis,l,t ≤S l,t

[0060] -Q mess,max ·S l,t ≤Q mess,l,t ≤Q mess,max ·S l,t

[0061] -P mess,max ·S l,t ≤P mess,l,t ≤P mess,max ·S l,t

[0062]

[0063] S soc,min ≤S soc,t ≤S soc,max

[0064] S soc,σ ≥S soc,0

[0065] Among them, P ch,l,t , P dis,l,t are the active power of charging and discharging of the mobile energy storage connected to the lth access point at time t; S ch,l,t , S dis,l,t are binary variables. When the mobile energy storage is charged or discharged at the lth access point, the corresponding value is 1; P mess,max , Q mess,max are the maximum active and reactive power of mobile energy storage respectively; S mess is the rated apparent power of the mobile energy storage; S soc,t is the charge state of the mobile energy storage at time t, S soc,max , S soc,min They are the maximum and minimum charge quantity limits that mobile energy storage can accommodate; S soc,σ is the final state of charge value of the mobile energy storage; S soc,0 is the initial charge value of the mobile energy storage.

[0066] In a second aspect, the present invention provides a dispatching system for mobile energy storage, the system comprising:

[0067] A matrix construction module is used to obtain the node distance between any two nodes in the target distribution network and the node time consumed by the mobile energy storage to move between any two nodes, so as to respectively construct a distance matrix and a time matrix according to the node distance and the node time;

[0068] A scheduling scheme building module is used to assume that there is an equivalent switch between the mobile energy storage and its accessible nodes, and to build an equivalent scheduling scheme for the mobile energy storage;

[0069] An objective function construction module, used for obtaining the total revenue of the operator according to the distance matrix and the time matrix, and constructing an objective function with the goal of maximizing the total revenue of the operator;

[0070] A constraint condition construction module, used to construct the constraint conditions of the objective function, wherein the constraint conditions include distribution network operation constraints, renewable energy output constraints, and mobile energy storage operation constraints;

[0071] The solution module is used to solve the objective function and obtain the optimal scheduling planning scheme for mobile energy storage.

[0072] In a third aspect, the present invention provides a readable storage medium, wherein the readable storage medium stores one or more programs, which, when executed by a processor, implement the above-mentioned scheduling method for mobile energy storage.

[0073] In a fourth aspect, the present invention provides an electronic device, the electronic device comprising a memory and a processor, wherein:

[0074] The memory is used to store computer programs;

[0075] When the processor is used to execute the computer program stored in the memory, the above-mentioned mobile energy storage scheduling method is implemented.

[0076] Compared with the prior art, the present invention has the following advantages:

[0077] A new equivalent transformation model is defined to describe the dispatching process of mobile energy storage. By converting the time and cost of mobile energy storage dispatching into the parameters of equivalent switch switching, the distance matrix and time matrix are constructed respectively, so as to decouple the power grid-mobile energy storage mobile network and realize the mapping of the influencing factors of the mobile energy storage mobile network to the operation constraints of the distribution network, which provides a new idea for solving the problem of mobile energy storage dispatching.

[0078] 1. The present invention defines a new equivalent transformation model to describe the scheduling process of mobile energy storage, that is, to achieve optimal scheduling of mobile energy storage by utilizing equivalent transformation, specifically, by converting the time and cost of mobile energy storage scheduling into parameters of equivalent switch switching, so as to construct a distance matrix and a time matrix respectively, so as to decouple the power grid-mobile energy storage mobile network, realize the mapping of the influencing factors of the mobile energy storage mobile network to the network operation constraints of the distribution network, and provide a new idea for solving the problem of mobile energy storage scheduling; at the same time, the present invention takes the maximization of the total revenue of the operator as the goal, constructs the objective function, which is conducive to improving the economic benefits of the distribution network operator, and finally, by using the GUROBI commercial solver to solve the second-order cone programming problem, the switch after the equivalent transformation is controlled, that is, the access node and access time of the mobile energy storage are optimized, and then the optimal scheduling planning scheme of the mobile energy storage is obtained, thereby achieving maximum economic benefits.

[0079] 2. The present invention verifies the effectiveness and feasibility of the mobile energy storage optimization scheduling model based on equivalent transformation in improving the IEEE33-node distribution network, that is, the use of mobile energy storage can maximize the benefits of distribution network operators while maintaining stable operation of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0080] Figure 1 A flow chart of a method for dispatching mobile energy storage according to an embodiment of the present invention;

[0081] Figure 2 A schematic diagram of equivalent transformation of mobile energy storage proposed in one embodiment of the present invention;

[0082] Figure 3A schematic diagram of the structure of an improved IEEE33 node power distribution system proposed in one embodiment of the present invention;

[0083] Figure 4 A schematic diagram of the structure of a mobile energy storage dispatching system proposed in one embodiment of the present invention.

[0084] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0085] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be understood by people with general skills in the field to which the present invention belongs. "Including" and similar words used in this article mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0086] See also Figure 1 An embodiment of the present invention provides a method for dispatching mobile energy storage, the method comprising steps S101 to S105, wherein:

[0087] Step S101: Obtain the node distance between any two nodes in the target distribution network and the node time consumed by the mobile energy storage to move between any two nodes, so as to construct a distance matrix and a time matrix according to the node distance and the node time respectively;

[0088] It should be noted that in the process of constructing an equivalent scheme for mobile energy storage scheduling, two aspects are included: one is the representation of the road time network, and the other is the representation of the equivalent operation mode of mobile energy storage; the description method of the road time network is as follows: the construction of a scheduling model for mobile energy storage requires consideration of the interaction between the road network and the power grid, so the distance and time parameters of the mobile energy storage movement are represented in matrix form.

[0089] Specifically, in some embodiments, the distance matrix is ​​constructed according to the following formula:

[0090]

[0091] The time matrix is ​​constructed according to the following formula:

[0092]

[0093] Among them, Dm,n,t Represents the total distance moved by the mobile energy storage, D 1,M and D M,1 Both represent the distance from the 1st node to the Mth node or from the Mth node to the 1st node, T m,n,t represents the time matrix, T 1,M and T M,1 Both represent the time consumed by the mobile energy storage from the 1st node to the Mth node or from the Mth node to the 1st node, T m,n,t Represents the total moving time of mobile energy storage.

[0094] Step S102: Assuming that there is an equivalent switch between the mobile energy storage and its accessible nodes, and constructing an equivalent scheduling scheme for the mobile energy storage;

[0095] It should be pointed out that in this step, an equivalent switch method is used to describe the dispatch of mobile energy storage. The mobile energy storage is regarded as an additional node of the original distribution network, and it is assumed that there is an equivalent switch between the mobile energy storage and different charging and discharging nodes. If the mobile energy storage needs to move to a certain node for power supply, it is regarded as an equivalent switch between the mobile energy storage and this node. When the mobile energy storage moves to this node, the corresponding equivalent switch is closed. When it is not at this node, the corresponding equivalent switch is in the open state, thereby constructing an equivalent switch model. For specific situations, please refer to Figure 2 .

[0096] In some embodiments, the dispatch equivalent scheme of mobile energy storage is as follows:

[0097]

[0098] Wherein, formula (1) indicates that at most one switch is allowed to be closed at time t, S l,t is a binary variable, indicating the on / off state of the lth equivalent switch at time t; Formula (2) ensures that only one switch can be switched to another at time t, X m,n,t is a binary variable, indicating whether the mth switch is disconnected and the nth switch is closed at time t; Formula (3) indicates that when switching between equivalent switches, all equivalent switches are in the open state, otherwise, one equivalent switch must be closed; Formula (4) indicates that there must be a certain time interval between the switching of different equivalent switches, that is, the mobile storage energy cannot be transported instantly, σ m,n,t is the switching time from m to n at time t; Formula (5) explains the relationship between the equivalent switch switching flag and the equivalent switch on and off states, α l,t is a binary variable, indicating whether the lth equivalent switch switches from the open state to the closed state at time t; β l,tis a binary variable, indicating whether the lth equivalent switch switches from the closed state to the open state at time t; Formula (6) illustrates the relationship between the equivalent switch closure and the equivalent switch switching flag. If X m,n,t-1 -X m,n,t =1, which means that the equivalent switch changes from open state to closed state at time t, so α n,t =1,η n,t =0,η n,t is an auxiliary variable, and its function is to ensure that the inequality holds. Formula (7) ensures that the equivalent switch when disconnected is consistent with the initial equivalent switch when switched.

[0099] It should also be pointed out that, for the above binary variables, if it is in an open state, the corresponding variable value is 1, and if it is in a closed state, the corresponding variable value is 0. In some other embodiments of the present invention, other numerical values ​​can also be set to define the above binary variables.

[0100] Step S103: obtaining the total revenue of the operator according to the distance matrix and the time matrix, and constructing an objective function with the goal of maximizing the total revenue of the operator;

[0101] It should be pointed out that the objective function of the optimal dispatch of mobile energy storage based on equivalent transformation is to maximize the total revenue of the distribution network operator, which includes the operator's electricity sales revenue, the operator's upper-level electricity purchase cost, the cost of wind and solar power abandonment, and the dispatch cost of mobile energy storage. The mathematical expression is as follows:

[0102]

[0103] Among them, C all is the total revenue of the operator, and the goal is to maximize the total revenue. sell,use is the operator’s electricity sales revenue, C buy,grid is the operator’s upper-level electricity purchase cost, C loss,power is the cost of curtailing wind and solar power, C switch The corresponding cost after the mobile energy storage is equivalent to the switch, including the investment cost, maintenance cost and switching cost of the switch, and its total value is consistent with the cost consumed by the mobile energy storage.

[0104] Furthermore, the objective function C all The specific composition of the elements is as follows:

[0105]

[0106] C sell,use =(τ·P load,i,t SP t )

[0107] C buy,grid =(τ·PP t·P grid,t )

[0108] C switch =C invest +C repair +C toggle

[0109] In the above formula: RDG Penalty costs for curtailing wind and solar power; is the abandoned wind and solar power of photovoltaic and wind power generation at node i at time t; τ is the time step; P load,i,t is the active power of the load of node i at time t; SP t is the electricity price at time t; P grid,t is the active power PP from the upper power purchasing grid at time t t is the electricity purchase price at time t; C switch is the total cost of the equivalent switch, which is determined by the investment cost C invest , Maintenance cost C repair and switching cost C toggle composition.

[0110] In addition, in some embodiments, the total operating cost of the mobile energy storage after being equivalent is converted into the cost of the equivalent switch, that is, the cost expression after the mobile energy storage is equivalent to the switch is as follows:

[0111] C switch =C invest +C repair +C toggle (8)

[0112] In formula (8), the total operating cost of the equivalent switch is C switch The investment cost C invest , Maintenance cost C repair and switching cost C toggle The specific expressions of various costs are as follows:

[0113] C invest =L mess ·E mess ·μ(9)

[0114] C repair =G mess ·E mess (10)

[0115]

[0116] In the above formula, L mess E is the investment cost per unit capacity of mobile energy storage; mess is the rated capacity of mobile energy storage; μ is the loss rate; G messis the maintenance cost per unit capacity of mobile energy storage; the switch cost C toggle is the sum of all switch operation and maintenance costs during the scheduling period, as shown in formula (11), where C path D is the cost per kilometer of mobile energy storage; m,n,t It is the total distance moved by the mobile energy storage.

[0117] Step S104: constructing constraint conditions of the objective function, wherein the constraint conditions include distribution network operation constraints, renewable energy output constraints, and mobile energy storage operation constraints;

[0118] It should be noted that by configuring the historical data based on renewable energy output and load, a typical scenario of distribution network operation is generated; on the basis of this typical scenario, the profit maximization of the distribution network operator is taken as the objective function, and the mobile energy storage scheduling process constraints, distribution network operation constraints, and mobile energy storage operation configuration constraints are taken as constraints.

[0119] In some embodiments, the implementation of mobile energy storage optimization scheduling based on equivalent transformation requires the establishment of relevant constraints to achieve convergence of the optimal goal. The expressions of the relevant constraints are as follows:

[0120] 1. Distribution network operation constraints

[0121]

[0122]

[0123] I i,j,t ≤I i,j,max (16)

[0124] U min ≤U i,t ≤U max (17)

[0125] This design adopts the Dist-Flow branch power flow model based on the radial distribution network, as shown in the above formula: Formula (13) and Formula (14) are node power balance constraints, where P RDG,i,t / Q RDG,i,t is the active power / reactive power actually consumed by the photovoltaic and wind power generation at node i at time t, P mess,l,t / Q mess,l,t is the active power / reactive power generated by the mobile energy storage connected to the lth access point (i.e., when the lth equivalent switch is closed) at time t, P i,j,t / Q i,j,t is the active / reactive power of the ij branch at time t; r k,i / x k,i is the branch resistance / reactance, I k,i,tis the effective value of the current at branch ki at time t; Formula (15) is the branch flow constraint, where U i,t is the effective value of the voltage at node i at time t; Equations (16) and (17) limit the branch current and node voltage to a safe range, where I i,j,max is the maximum current that branch ij can withstand, U min / U max The minimum / maximum voltage limits for each node.

[0126] II. Renewable Energy Output Constraints

[0127]

[0128] The renewable energy output constraint ensures the power balance of renewable energy output; in the above formula: is the true value of the active power generated by photovoltaic and wind power generation at node i at time t.

[0129] 3. Mobile Energy Storage Operation Constraints

[0130] P mess,l,t =P ch,l,t +P dis,l,t (18)

[0131] 0≤P ch,l,t ≤P mess,max ·S ch,l,t (19)

[0132] -P mess,max ·S dis,l,t ≤P dis,l,t ≤0(20)

[0133] S ch,l,t +S dis,l,t ≤S l,t (twenty one)

[0134] -Q mess,max ·S l,t ≤Q mess,l,t ≤Q mess,max ·S l,t (twenty two)

[0135] -P mess,max ·S l,t ≤P mess,l,t ≤P mess,max ·S l,t (twenty three)

[0136]

[0137] S soc,min ≤S soc,t ≤S soc,max(25)

[0138] S soc,σ ≥S soc,0 (26)

[0139] The operation constraints of mobile energy storage ensure the normal operation of mobile energy storage in the distribution network and the dispatching process; In the above formula: The active power of mobile energy storage consists of charging power and discharging power, where charging power is positive and discharging power is negative, as shown in formula (18) to formula (20), where P ch,l,t / P dis,l,t is the active power charged / discharged by the mobile energy storage connected to the lth access point at time t, S ch,l,t / S dis,l,t is a binary variable. When the mobile energy storage is charged / discharged at the lth access point, its value is 1. Formula (21) ensures that the mobile energy storage cannot be charged / discharged at the same time and the active power output is zero when it is not connected to the grid. Formulas (22) and (23) constrain the reactive power and active power of the mobile energy storage between the upper and lower limits, where P mess,max / / Q mess,max is the maximum active / reactive power of mobile energy storage; Formula (24) is the apparent power constraint, S mess is the rated apparent power of the mobile energy storage; Formula (25) limits the maximum charge and minimum charge stored in the mobile energy storage, where S soc,t is the charge state of the mobile energy storage at time t, S soc,max / S soc,min is the maximum / minimum charge quantity limit that the mobile energy storage can accommodate; Formula (26) constrains the final charge state of the mobile energy storage to be no less than the initial value to ensure the cyclic operation of the mobile energy storage.

[0140] Step S105: Solve the objective function to obtain the optimal scheduling planning scheme for mobile energy storage.

[0141] Exemplarily, in this step, the GUROBL commercial solver is used to solve the objective function, that is, to solve the second-order cone nonlinear problem, so as to obtain the optimal scheduling planning scheme, which includes when and to which node the mobile energy storage moves, and whether to supply power or discharge.

[0142] In summary, the present invention firstly establishes an equivalent model for mobile energy storage scheduling, which can convert the time and cost of mobile energy storage scheduling in the distribution network into the time and cost of equivalent switch switching; and on the basis of constructing this model, taking the profit maximization of the distribution network operator as the objective function, and then taking the scheduling process constraints, distribution network operation constraints, and mobile energy storage operation configuration constraints as constraints, a mobile energy storage optimization scheduling model is constructed; by collecting data such as renewable energy output and time-of-use electricity prices, typical scenarios are selected and generated, and on the basis of this typical scenario, different configuration schemes are set and finally the mixed integer nonlinear programming problem involved is solved by the GUROBI commercial solver, so as to obtain the optimal scheduling scheme of mobile energy storage and verify the advantages and disadvantages of the scheme; this method simplifies a distribution network-transportation network coupling problem into a pure distribution network problem by converting the time and cost of mobile energy storage scheduling in the distribution network into an equivalent time and cost of switch switching, and provides a new idea for solving the mobile energy storage scheduling problem while achieving the economic goal.

[0143] For examples and not limitation, see Figure 3 Taking the improved IEEE33 node distribution system as an example, the system reference capacity is 10MVA, the reference voltage is 12.66kV, and the node voltage allowable range is 0.95~1.05 / . The branch current allowable range is 0~1.05 / . The selected locations of distributed power sources are: photovoltaic power generation is installed at nodes 9 and 33, and wind power generation is installed at nodes 1, 2, and 15, with a power factor of 0.9; the mobile energy storage access points are nodes 5, 17, and 33, and its rated capacity is 2.2MWh. A mobile energy storage is selected for scheduling, and the influence of charging and discharging plug-in time is not considered. The other correlation coefficients are selected as shown in Table 1 below:

[0144] Table 1 Correlation coefficient table

[0145]

[0146] Furthermore, renewable energy output data and time-of-use electricity price data are obtained through actual collection, and representative data results are selected as the basis for construction to establish corresponding typical scenarios.

[0147] Furthermore, in order to verify the rationality and advancement of the proposed planning model, different configuration schemes of the system are implemented in typical scenarios.

[0148] Solution 1: Optimal dispatch of the distribution network without using the mobile energy storage designed by the present invention.

[0149] Solution 2: Optimal dispatching of distribution network with the participation of mobile energy storage designed by the present invention.

[0150] In Option 1, the amount of wind and solar power abandoned is 2.9230MWh, and the total profit of the distribution network operator is 6,392.52 yuan.

[0151] In Scheme 2, the optimized dispatching process of mobile energy storage is shown in Table 2 below:

[0152] Table 2 Scheduling process related parameters

[0153]

[0154] In Option 2, the amount of wind and solar power abandoned is 2.0589MWh, and the total profit of the distribution network operator is 7555.56 yuan.

[0155] From the analysis of the above optimization results, it can be concluded that Scheme 2 adds a mobile energy storage compared to Scheme 1. The optimized dispatch of the distribution network with the participation of mobile energy storage reduces the amount of wind and solar power abandonment by 0.865MWh within 24 hours, and increases the total revenue of the distribution network operator by 1,163.04 yuan, with a profit increase of 15.39%. From the optimization results, it can be seen that the use of mobile energy storage to participate in power regulation is conducive to the consumption of renewable energy, and fully reflects the superiority of the economic benefits brought to operators by mobile energy storage acting on the distribution system.

[0156] In summary, the above-mentioned mobile energy storage scheduling method has the following beneficial effects:

[0157] 1. The dispatching method of mobile energy storage based on equivalent transformation of the present invention adopts MATLAB platform to build relevant models, and solves the nonlinear programming problem through GUROBI commercial solver, and converts the nonlinear constraints in the model into linear constraints, thereby improving the calculation efficiency and the response speed of the dispatching model.

[0158] 2. The mobile energy storage in the present invention can flexibly adjust its operating mode according to actual needs, and the equivalent transformation method can better adapt to this flexibility, so that the system can quickly adjust the scheduling strategy according to changes in demand.

[0159] 3. The present invention optimizes the dispatching method of mobile energy storage based on equivalent transformation, takes the difficulty of the mobile energy storage dispatching control process and the unclear control requirements as the contradictions, and establishes a method for replacing the mobile energy storage dispatching process with the action mode of an equivalent switch, thereby achieving the simplification and automation of the dispatching process and improving the controllability and flexibility of the distribution system; accordingly, the implementation and optimization of this method can promote the further development of related technologies and promote technological innovation in energy storage technology and other related fields.

[0160] See also Figure 4 , which is a schematic diagram of the structure of a mobile energy storage dispatching system in one embodiment of the present invention, the system includes:

[0161] A matrix construction module 10 is used to obtain the node distance between any two nodes in the target distribution network and the node time consumed by the mobile energy storage to move between any two nodes, so as to respectively construct a distance matrix and a time matrix according to the node distance and the node time;

[0162] A scheduling scheme building module 20, used to assume that there is an equivalent switch between the mobile energy storage and its accessible nodes, and to build an equivalent scheduling scheme for the mobile energy storage;

[0163] An objective function construction module 30 is used to obtain the total revenue of the operator according to the distance matrix and the time matrix, and to construct an objective function with the goal of maximizing the total revenue of the operator;

[0164] A constraint condition construction module 40 is used to construct the constraint conditions of the objective function, wherein the constraint conditions include distribution network operation constraints, renewable energy output constraints, and mobile energy storage operation constraints;

[0165] The solution module 50 is used to solve the objective function to obtain the optimal scheduling planning scheme for the mobile energy storage.

[0166] On the other hand, the present invention further proposes a readable storage medium having one or more programs stored thereon, which implement the above-mentioned mobile energy storage scheduling method when executed by a processor.

[0167] On the other hand, the present invention further proposes an electronic device, including a memory and a processor, wherein the memory is used to store computer programs, and the processor is used to execute the computer programs stored in the memory to implement the above-mentioned mobile energy storage scheduling method.

[0168] Those skilled in the art will appreciate that the logic and / or steps represented in the flowchart or otherwise described herein, for example, may be considered as an ordered list of executable instructions for implementing logical functions, and may be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For purposes of this specification, "computer-readable medium" may be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0169] More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering or, if necessary, processing in another suitable manner, and then stored in a computer memory.

[0170] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or a combination thereof: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0171] Although the embodiments of the present invention are described in detail above, it is obvious to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations are within the scope and spirit of the present invention as described in the claims. Moreover, the present invention described herein may have other embodiments and may be implemented or realized in a variety of ways.

Claims

1. A method for dispatching mobile energy storage, characterized in that: The method comprises: Obtain the node distance between any two nodes in the target distribution network and the node time consumed by the mobile energy storage to move between any two nodes, so as to construct a distance matrix and a time matrix according to the node distance and the node time respectively; Assume that there is an equivalent switch between the mobile energy storage and its accessible nodes, and construct an equivalent scheduling scheme for the mobile energy storage; Obtaining the total revenue of the operator according to the distance matrix and the time matrix, and constructing an objective function with the goal of maximizing the total revenue of the operator; Constructing constraint conditions of the objective function, wherein the constraint conditions include distribution network operation constraints, renewable energy output constraints, and mobile energy storage operation constraints; The objective function is solved to obtain the optimal scheduling planning scheme for mobile energy storage.

2. The method for dispatching mobile energy storage according to claim 1, characterized in that: The step of obtaining the node distance between any two nodes in the target distribution network and the node time consumed by the mobile energy storage to move between any two nodes, and constructing a distance matrix and a time matrix according to the node distance and the node time respectively includes: The distance matrix is ​​constructed according to the following formula: The time matrix is ​​constructed according to the following formula: Among them, D m,n,t Represents the total distance moved by the mobile energy storage, D 1,M and D M,1 Both represent the distance from the 1st node to the Mth node or from the Mth node to the 1st node, T m,n,t represents the time matrix, T 1,M and T M,1 Both represent the time consumed by the mobile energy storage from the 1st node to the Mth node or from the Mth node to the 1st node, T m,n,t Represents the total moving time of mobile energy storage.

3. The method for dispatching mobile energy storage according to claim 1, characterized in that: The step of assuming that there is an equivalent switch between the mobile energy storage and its accessible nodes and constructing an equivalent scheduling scheme for the mobile energy storage includes: If the mobile energy storage needs to be moved to a certain node to supply power, it is considered that there is an equivalent switch between the mobile energy storage and this node; When the mobile energy storage moves to this node, the corresponding equivalent switch is closed, and when it is not at this node, the corresponding equivalent switch is in the open state; The dispatch equivalent scheme of mobile energy storage is constructed according to the following formula: Among them, S l,t is a binary variable, indicating the on / off state of the lth equivalent switch at time t; X m,n,t , are binary variables, representing the time at t, t+σ m,n,t-1 Time, t+σ m,n,t At time t, at time t-1, whether the mth switch is open and the nth switch is closed; t+σ m,n,t , t+σ m,n,t-1 Respectively represent the switching time from m to n at time t and time t-1; α l,t , α n,t Both are binary variables, indicating whether the lth and nth equivalent switches are switched from the open state to the closed state at time t; β l,t , β m,t are binary variables, indicating whether the lth and mth equivalent switches are switched from the closed state to the open state at time t; S l,t-1 It represents the on / off state of the lth equivalent switch at time t-1; it is a binary variable, indicating whether the mth equivalent switch switches from the closed state to the open state at time t.

4. The method for dispatching mobile energy storage according to claim 3, characterized in that: The step of obtaining the total revenue of the operator according to the distance matrix and the time matrix and constructing an objective function with the goal of maximizing the total revenue of the operator comprises: The objective function is constructed according to the following formula: Among them, C all is the total revenue of the operator, and the goal is to maximize the total revenue. sell,use is the operator’s electricity sales revenue, C buy,grid is the operator’s upper-level electricity purchase cost, C loss,power is the cost of curtailing wind and solar power, C switch The total cost of mobile energy storage equivalent to the switch; The total cost of mobile energy storage equivalent to a switch is calculated according to the following formula: C switch =C invest +C repair +C toggle Among them, C invest represents the investment cost, C repair represents the maintenance cost, C toggle represents the switching cost; The cost of curtailing wind and solar power is calculated using the following formula: The operator's electricity sales revenue is calculated according to the following formula: C sell,use =(τ·P load,i,t ·SP t ) The operator's upper-level electricity purchase cost is calculated according to the following formula: C buy,grid =(τ·PP t ·P grid,t ) Among them, η RDG Penalty costs for curtailing wind and solar power; is the abandoned wind and solar power of photovoltaic and wind power generation at node i at time t; τ is the time step; P load,i,t is the active power of the load of node i at time t; SP t is the electricity price at time t; P grid,t is the active power PP from the upper power purchasing grid at time t t is the electricity purchase price at time t.

5. The method for dispatching mobile energy storage according to claim 4, characterized in that: The investment cost is calculated according to the following formula: C invest =L mess ·AND mess ·μ The maintenance cost is calculated according to the following formula: C repair =G mess ·E mess The switching cost of the equivalent switch is calculated according to the following formula: Among them, L mess E is the investment cost per unit capacity of mobile energy storage; mess is the rated capacity of mobile energy storage; μ is the loss rate; G mess is the maintenance cost per unit capacity of mobile energy storage; C path D is the cost per kilometer of mobile energy storage; m,n,t is the total moving distance of the mobile energy storage; X m,n,t is a binary variable, indicating whether the mth switch is open and the nth switch is closed at time t.

6. The method for dispatching mobile energy storage according to claim 5, characterized in that: The step of constructing the constraint conditions of the objective function, wherein the constraint conditions include distribution network operation constraints, renewable energy output constraints, and mobile energy storage operation constraints, comprises: The distribution network operation constraints are constructed according to the following formula: I i,j,t ≤I i,j,max IN min ≤U i,t ≤U max Among them, P RDG,i,t , Q RDG,i,t are respectively the active power and reactive power actually consumed by the photovoltaic and wind power generation at node i at time t, P mess,l,t , Q mess,l,t are the active power and reactive power generated by the mobile energy storage connected to the lth access point at time t, P i,j,t , Q i,j,t are respectively the active power and reactive power of the ij branch at time t; r k,i 、x k,i 、r i,j 、x i,j They are ki branch resistance, ki branch reactance, ij branch resistance, ij branch reactance, I k,i,t is the effective value of the current at branch ki at time t; U i,t is the effective value of the voltage at node i at time t; I i,j,max is the maximum current that branch ij can withstand; U min , U max The minimum and maximum voltage limits for each node; P load,i,t represents the active power of the load at node i at time t, P k,i,t represents the active power of branch ki at time t; Q load,i,t represents the reactive power of the load at node i at time t, Q k,i,t represents the reactive power of branch ki at time t, I i,j,t Represents the effective value of the current at branch ij at time t.

7. The method for dispatching mobile energy storage according to claim 6, characterized in that: The step of constructing the constraint conditions of the objective function, wherein the constraint conditions include distribution network operation constraints, renewable energy output constraints, and mobile energy storage operation constraints, comprises: The renewable energy output constraint is constructed according to the following formula: in, represents the real value of active power generated by photovoltaic and wind power generation at node i at time t, It represents the abandoned wind and solar power of photovoltaic and wind power generation at node i at time t.

8. The method for dispatching mobile energy storage according to claim 6, characterized in that: The step of constructing the constraint conditions of the objective function, wherein the constraint conditions include distribution network operation constraints, renewable energy output constraints, and mobile energy storage operation constraints, comprises: The mobile energy storage operation constraints are constructed according to the following formula: P mess,l,t =P ch,l,t +P dis,l,t 0≤P ch,l,t ≤P mess,max ·S ch,l,t -P mess,max ·S dis,l,t ≤P dis,l,t ≤0 S ch,l,t +S dis,l,t ≤S l,t -Q mess,max ·S l,t ≤Q mess,l,t ≤Q mess,max ·S l,t -P mess,max ·S l,t ≤P mess,l,t ≤P mess,max ·S l,t S soc,min ≤S soc,t ≤S soc,max S soc,σ ≥S soc,0 Among them, P ch,l,t , P dis,l,t are the active power of charging and discharging of the mobile energy storage connected to the lth access point at time t; S ch,l,t , S dis,l,t are binary variables. When the mobile energy storage is charged or discharged at the lth access point, the corresponding value is 1; P mess,max , Q mess,max are the maximum active and reactive power of mobile energy storage respectively; S mess is the rated apparent power of the mobile energy storage; S soc,t is the charge state of the mobile energy storage at time t, S soc,max , S soc,min They are the maximum and minimum charge quantity limits that mobile energy storage can accommodate; S soc,σ is the final state of charge value of the mobile energy storage; S soc,0 is the initial charge value of the mobile energy storage.

9. A dispatching system for mobile energy storage, characterized in that: The system comprises: A matrix construction module is used to obtain the node distance between any two nodes in the target distribution network and the node time consumed by the mobile energy storage to move between any two nodes, so as to respectively construct a distance matrix and a time matrix according to the node distance and the node time; A scheduling scheme building module is used to assume that there is an equivalent switch between the mobile energy storage and its accessible nodes, and to build an equivalent scheduling scheme for the mobile energy storage; An objective function construction module, used for obtaining the total revenue of the operator according to the distance matrix and the time matrix, and constructing an objective function with the goal of maximizing the total revenue of the operator; A constraint condition construction module, used to construct the constraint conditions of the objective function, wherein the constraint conditions include distribution network operation constraints, renewable energy output constraints, and mobile energy storage operation constraints; The solution module is used to solve the objective function and obtain the optimal scheduling planning scheme for mobile energy storage.

10. A readable storage medium, characterized in that: The readable storage medium stores one or more programs, which, when executed by a processor, implement the scheduling method for mobile energy storage as described in any one of claims 1 to 8.

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