Flexible power distribution network optimization operation method considering intelligent energy storage soft switch

Abstract

The invention relates to the technical field of low-carbon operation of a power system, and discloses a flexible power distribution network optimized operation method considering an intelligent energy storage soft switch, which comprises the following steps of: establishing an optimal power flow model of a flexible power distribution network provided with the intelligent energy storage soft switch (ESOP), and constructing an objective function and a function constraint of the optimal power flow model; solving the optimal power flow model according to the data of the flexible power distribution network to obtain the optimal active power flow distribution of the flexible power distribution network; establishing a carbon flow calculation model of the flexible power distribution network, solving the carbon flow calculation model of the flexible power distribution network, and performing calculation to obtain whole-network real-time carbon flow distribution and total carbon emission of the flexible power distribution network; and S3, adjusting the carbon emission flow in the flexible power distribution network according to a calculation result in the step S3, so that the flexible power distribution network operates optimally, the carbon flow distribution of the flexible power distribution network can be calculated in real time, the ESOP in the flexible power distribution network adjusts the carbon flow distribution of the flexible power distribution network, the target cost in the flexible power distribution network is minimized, and low-carbon and economical operation of the flexible power distribution network is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of low-carbon operation of power systems, and specifically to an optimized operation method for a flexible distribution network considering intelligent energy storage soft switches. Background Technique

[0002] With the large-scale development of new energy units, such as distributed power sources (DG) like microturbines (MT), wind power (WT), and photovoltaic power (PV) being massively connected to the distribution network, the role of the distribution system has gradually evolved from a traditional electric energy distribution network to an energy interaction and service platform that deeply integrates the interaction of sources, loads, and storage. As a result, the flexible distribution network (FDN) has emerged, and the low-carbon optimized operation of the flexible distribution network with the goal of low-carbon environmental protection will become a new trend.

[0003] The FDN transformed by intelligent soft open points (SOP) can flexibly operate the distribution network in a closed-loop situation and has the following characteristics: 1. Closed-loop nature, where short-circuit current can be well blocked and the FDN can operate in a closed loop; 2. Flexibility, where certain specific nodes can achieve continuous control, thereby changing the power flow distribution in the distribution network. The intelligent energy storage soft switch (ESOP) integrated with the SOP and the energy storage system can store the clean electric energy generated by the DG while realizing bidirectional power flow regulation, improving the ability of the distribution system to absorb new energy. The FDN schedules the power flow of the entire network with the help of these flexible network devices. The flexible network devices can be regarded as energy hubs, through which feeders can exchange power flow and carbon emission flow in a wide area.

[0004] The core concept of the ESOP is to replace the traditional tie switch to achieve flexible electrical interconnection between feeders, support feeder load balancing, and efficient absorption of distributed power sources, etc. The converters on both sides are in a symmetric form, which can achieve active power transmission, reactive power real-time control, and four-quadrant flexible operation. The converter is connected to the energy storage device to store clean energy, and the operation and maintenance loss of the ESOP is extremely small and can be approximated as lossless. The ESOP can switch between different control modes to meet the power control under normal conditions, realize the priority absorption of clean energy, and reduce the carbon emissions of the flexible distribution network.

[0005] The invention patent with the application publication number CN118281849A and the name of "Flexible Distribution Network Low-Carbon Optimal Operation Method Based on Carbon Emission Flow Theory" and the invention patent with the authorization (announcement) number CN118100154B and the name of "A Flexible Distribution Network Low-Carbon Planning Method Based on Carbon Emission Flow Theory" also introduce carbon emission flow theory indicators such as branch carbon flow rate and node carbon potential, attribute the carbon emissions on the power generation side to the load side, and obtain the carbon flow distribution of the entire flexible distribution network (FDN); based on the characteristics of distributed generation and intelligent soft switches, a flexible distribution network low-carbon planning model is established based on the improved carbon emission flow theory. However, there is a lack of analysis on the energy storage and regulation functions of ESOP and the impact of energy storage devices on the carbon emission flow of the flexible distribution network.

[0006] Currently, the research on the calculation of carbon emission flow in the power system mainly focuses on the transmission network level. There is still a lack of a method for calculating the carbon emission flow of a flexible distribution network considering intelligent energy storage soft switches and timely adjusting the carbon emission flow of the flexible distribution network to optimize the operation of the flexible distribution network. Summary of the Invention

[0007] The purpose of the present invention is to provide an optimal operation method for a flexible distribution network considering intelligent energy storage soft switches to solve the problems such as the lack of accurate carbon flow distribution and optimal operation method in the existing installed ESOPDE soft distribution network mentioned in the above background technology. Based on the improved carbon flow theory, considering the functional characteristics of ESOP, the carbon emission flow of the flexible distribution network is calculated. The storage characteristics of the intelligent energy storage soft switch in the flexible distribution network considering intelligent energy storage soft switches and the close relationship between power flow and carbon emission flow are described in detail. A calculation method for the carbon emission flow of the flexible distribution network is provided, and the carbon emission flow of the flexible distribution network is adjusted based on the above method to achieve the optimal operation of the flexible distribution network and broaden the new vision of the low-carbon power field.

[0008] To achieve the above purpose, the present invention provides the following technical solution: An optimal operation method for a flexible distribution network considering intelligent energy storage soft switches, including the following steps:

[0009] S1. Based on the power flow regulation ability and energy storage characteristics of the intelligent energy storage soft switch (ESOP), establish the optimal power flow model of the flexible distribution network installed with ESOP, and construct the objective function and function constraints of the optimal power flow model; Function constraints include: AC distribution system voltage balance equation, AC distribution system node power balance equation, line power flow constraints in AC distribution system, unit operation constraints in AC distribution system, ESOP operation power constraint, ESOP operation capacity constraint, ESOP operation power loss constraint, ESOP energy storage device operation constraint, ESOP stored electricity constraint, ESOP virtual carbon storage constraint, node carbon potential equality constraint of virtual node k, node carbon potential equality constraint of ESOP energy storage device, ESOP branch carbon flow rate constraint, node carbon potential equality constraint of ESOP branch connection nodes, and photovoltaic inverter operation constraint S2. Input the flexible distribution network data into the optimal power flow model of the flexible distribution network, and solve the above optimal power flow model to obtain the optimal active power flow distribution of the flexible distribution network; S3. Establish a carbon flow calculation model for the flexible distribution network, solve the carbon flow calculation model of the flexible distribution network, and calculate the charging and discharging conditions of the ESOP and the changes in virtual carbon storage, the real-time carbon flow distribution of the entire flexible distribution network and the total carbon emissions; S4. Adjust the carbon emission flow in the flexible distribution network according to the calculation results of the real-time carbon flow distribution of the entire flexible distribution network and the total carbon emissions obtained in step S3, so as to minimize the objective function in the optimal power flow model. Based on the energy storage and regulation functions of the ESOP itself, combined with the calculated real-time stored electricity and virtual carbon storage of the ESOP, verify the consumption of clean energy output by the ESOP, reduce the carbon emissions of the flexible distribution network system, and flexibly regulate the power flow and carbon emission flow of the flexible distribution network in real time, so that the power flow distribution of the flexible distribution network conforms to the optimal active power flow distribution, and the flexible distribution network operates optimally.

[0010] Optionally, the objective function in S1 aims to minimize the sum of the power purchase cost from the superior power grid, the operation and maintenance costs of each distributed power source, the network loss cost, and the carbon emission treatment cost.

[0011] Optionally, in the flexible distribution network equipped with the ESOP, the branch where the ESOP is installed is regarded as a branch with active power passing through and capable of emitting reactive power. The energy storage device of the ESOP is regarded as a new node in the flexible distribution network, and the connection point between the DC converter and the inverter in the ESOP is equivalent to a virtual node. The ESOP energy storage device participates in the power flow and carbon flow interaction of the distribution network through the virtual node. By calculating the real-time stored electricity and virtual carbon storage of the ESOP energy storage device, verify the role of the ESOP in consuming clean energy, reducing the carbon emissions of the flexible distribution network, and the flexible regulation ability of the distribution network power flow.

[0012] Optionally, the flexible distribution network data input in S2 includes unit parameters and base load parameters.

[0013] Optionally, the carbon flow calculation model for the flexible distribution network established in S3 includes: statistically calculating the output of each unit in the flexible distribution network and the carbon emission intensity EG of the unit, the charge and discharge power of the ESOP energy storage device and the real-time stored electricity, the power magnitude on the line equipped with ESOP, and clarifying the power flow direction on the line equipped with ESOP; defining key matrices and vectors.

[0014] Optionally, the key matrices and vectors defined in S3 include the carbon emission intensity vector of the generator set, the node carbon potential vector, the load carbon flow rate vector, the branch carbon flow rate distribution matrix, the branch carbon flow rate distribution matrix of the ESOP installed, the node carbon potential matrix of the ESOP energy storage device under different working states, and the ESOP virtual carbon storage amount vector.

[0015] Optionally, the carbon flow calculation model of the flexible distribution network is solved using MATLAB to obtain the real-time stored electricity and real-time virtual carbon storage amount of ESOP, the real-time carbon flow distribution of the flexible distribution network, and the total carbon emissions.

[0016] Optionally, solving the carbon flow calculation model of the flexible distribution network in S3 to obtain the real-time carbon flow distribution and total carbon emissions of the flexible distribution network includes: obtaining the power flow and carbon flow distribution of the entire flexible distribution network; the real-time output of the upper-level power grid and each unit of the flexible distribution network and the total carbon emissions injected; the change in the real-time virtual carbon storage amount of ESOP, reflecting the role of ESOP in consuming clean energy, reducing the carbon emissions of the flexible distribution network, and the flexible power flow regulation ability of the distribution network.

[0017] Optionally, the carbon emission flow in the flexible distribution network is adjusted in S4 specifically through the ESOP branch. At the same time, the ESOP energy storage device stores clean energy when the light is sufficient, enhancing the role of consuming clean energy, and during the period when the upper-level power grid injects high-carbon energy into the flexible distribution network, it emits low-carbon energy to reduce the carbon emission consumption of the distribution network and improve the carbon reduction ability of the flexible distribution network.

[0018] Compared with the prior art, the beneficial effects of the present invention are:

[0019] The present invention relates to the related research on carbon emission flow calculation of flexible distribution network considering intelligent energy storage soft switch. Considering the functional characteristics of ESOP, the branch installed with ESOP is equivalent to an almost lossless "branch", and at the same time, the connection point between the DC converter and the inverter in ESOP is equivalent to a virtual node to participate in the operation of the distribution system, which is convenient for the priority consumption of clean energy. Considering the low-carbon optimal operation of the flexible distribution network, an optimal power flow model of the flexible distribution network is established to obtain the optimal power flow distribution of the flexible distribution network; based on the carbon emission flow theory, combined with the operation characteristics of ESOP and the energy storage characteristics, a carbon flow calculation model of the flexible distribution network considering intelligent energy storage soft switch is constructed, which can quickly and accurately solve the power flow distribution and carbon emission flow distribution of the whole network during the low-carbon optimal operation of the flexible distribution network, can calculate the carbon flow distribution of the flexible distribution network in real time, and the ESOP in the flexible distribution network adjusts the carbon flow distribution of the flexible distribution network. Through the energy storage, regulation function and energy storage device of ESOP, the flexibility and low-carbon operation ability of the distribution network are further improved, and it can more effectively consume clean energy and reduce carbon emissions, and adjust the power flow and carbon emission flow of the distribution network in real time, so as to minimize the target cost in the flexible distribution network and realize the low-carbon and economic operation of the flexible distribution network, and realize the operation optimization of the flexible distribution network. Description of the Drawings

[0020] Figure 1 It is a flow chart of the flexible distribution network optimization operation method considering intelligent energy storage soft switch provided by the present invention;

[0021] Figure 2 It is a schematic diagram of the ESOP model;

[0022] Figure 3 It is a schematic diagram of the ESOP carbon emission flow model;

[0023] Figure 4 It is a schematic diagram of the low-carbon optimal operation of the flexible distribution network;

[0024] Figure 5 It is a schematic diagram of the typical daily load factor;

[0025] Figure 6 It is a schematic diagram of the output time series characteristics of wind power and photovoltaic power generation on a typical day;

[0026] Figure 7 It is a schematic diagram of the time-of-use electricity price of the superior power grid on a typical day;

[0027] Figure 8 It is a schematic diagram of the typical daily real-time carbon potential of the superior power grid;

[0028] Figure 9 It is a schematic diagram of the output of each generator set on a typical day;

[0029] Figure 10 It is a schematic diagram of the daily power change of ESOP on a typical day;

[0030] Figure 11 It is a schematic diagram of the carbon flow rate of each branch and the carbon flow rate of each node load in the whole network for a single time period. Specific implementation manner

[0031] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention.

[0032] The present invention provides a flexible distribution network optimal operation method considering an intelligent energy storage soft switch. Refer to Figure 1 , including the following steps:

[0033] S1. Based on the power flow regulation ability and energy storage characteristics of the intelligent energy storage soft switch (ESOP), establish an optimal power flow model for the flexible distribution network installed with the intelligent energy storage soft switch (ESOP), and construct the objective function and function constraints of the optimal power flow model.

[0034] The ESOP model is as shown in Figure 2 . Based on the power flow distribution characteristics and carbon flow theory of the power system, the ESOP branch installed between two feeders is regarded as a "branch" that allows active power to pass through and can emit reactive power. The energy storage device of the ESOP is regarded as a new node in the flexible distribution network. Considering the working state of the energy storage device and the power flow-carbon flow coupling relationship, for different operating states of the ESOP energy storage device, corresponding node carbon potential modeling is carried out. And the connection point of the ESOP DC converter and the converter is equivalent to a virtual node. The energy storage device of the ESOP participates in the power flow and carbon flow interaction of the distribution network through the virtual node. The operating state of the ESOP energy storage device affects the operating state of the virtual node. When the energy storage device is in the charging state, the virtual node is equivalent to a load node; when the energy storage device is in the discharging state, the virtual node is equivalent to a generator node; when the energy storage device is in the offline state, the virtual node is 0, and the ESOP is equivalent to an intelligent soft switch to participate in the operation of the distribution network. At the same time, considering that the node carbon potential calculation is related to the carbon emission source of this node, therefore, the node carbon potential of the virtual node is not the same as the node carbon potential of the ESOP energy storage device. The carbon emission flow model of the ESOP is as shown in Figure 3 .

[0035] The ESOP is a highly controllable power electronic device used to replace the connection switch for flexible closed-loop operation of the power flow in the distribution system. Compared with traditional switches, the ESOP can precisely control the real-time active and reactive power flows. Its energy storage device can effectively absorb the output of new energy units, enhance the low-carbon operation effect of the flexible distribution network, and regulate the voltage under normal operating conditions. The application of the ESOP will promote the flexibility and controllability of the distribution system. Given the close relationship between the power flow and carbon flow in the power system, when the ESOP and DG are connected to the distribution network, both will change the power flow distribution of the distribution network. At the same time, the ESOP energy storage device participates in the regulation of the power flow and carbon flow of the distribution network through virtual nodes, effectively absorbing the output of new energy units and affecting the distribution of the carbon emission flow of the entire distribution network. Therefore, when the ESOP regulates the active power in the distribution network, it can also regulate the distribution of the carbon flow in the distribution network.

[0036] In the present invention, based on the typical power market organization, network operation constraints in the distribution system, operation constraints of intelligent energy storage soft switches, and operation constraints of traditional power generation sources and distributed power sources, considering the low-carbon optimal operation of the flexible distribution network, with the goal of minimizing the sum of the power purchase cost from the superior power grid, the operation and maintenance costs of distributed power sources, the network loss cost, and the carbon emission cost, the branch where the ESOP is installed is regarded as a "branch" through which active power flows and reactive power can be generated. The energy storage device of the ESOP is regarded as a new node added to the flexible distribution network, and the connection point between the DC converter and the inverter in the ESOP is equivalent to a virtual node. The ESOP energy storage device participates in the interaction of the power flow and carbon flow of the distribution network through the virtual node, and finally constructs an optimal power flow model for the low-carbon optimal operation of the flexible distribution network.

[0037] S1. Based on the power flow regulation ability and energy storage characteristics of the intelligent energy storage soft switch (ESOP), constructing the optimal power flow model of the flexible distribution network installed with the intelligent energy storage soft switch (ESOP) includes constructing the objective function and constructing the function constraints.

[0038] In S1, the objective function aims to minimize the sum of the power purchase cost from the superior power grid, the operation and maintenance costs of each distributed power source, the network loss cost, and the carbon emission treatment cost.

[0039] In the flexible distribution network installed with the ESOP, the branch where the ESOP is installed is regarded as a branch through which active power flows and reactive power can be generated. The energy storage device of the ESOP is regarded as a new node added to the flexible distribution network, and the connection point between the DC converter and the inverter in the ESOP is equivalent to a virtual node. The ESOP energy storage device participates in the interaction of the power flow and carbon flow of the distribution network through the virtual node. By calculating the real-time stored electricity and virtual carbon storage of the ESOP energy storage device, the role of the ESOP in consuming clean energy, reducing the carbon emissions of the flexible distribution network, and the flexible power flow regulation ability of the distribution network are verified.

[0040] The function constraints of the above objective function include: the voltage balance equation of the AC distribution system, the node power balance equation of the AC distribution system, the line power flow constraint in the AC distribution system, the unit operation constraint of the AC distribution system, the operation power constraint of the ESOP, the operation capacity constraint of the ESOP, the operation power loss constraint of the ESOP, the operation constraint of the ESOP energy storage device, the node carbon potential equality constraint of the virtual node k, the node carbon potential equality constraint of the ESOP energy storage device, the branch carbon flow rate constraint of the ESOP, the node carbon potential equality constraint of the nodes connected by the ESOP branch, and the operation constraint of the PV inverter.

[0041] 1. Objective function:

[0042] (1);

[0043] In formula (1): T is the number of time periods; N bus is the number of distributed units in the flexible distribution network; N l is the number of branches in the flexible distribution network; c MT , c WT , c PV are the operation and maintenance costs of MT, WT, and PV respectively, with the unit of $ / (kW·h); P MT,i,t , P WT,i,t , P PV,i,t are respectively t at time i the output powers of the λ t th t gas turbine unit, wind turbine unit, and PV unit, with the unit of kW; P trans,t is t at time λ loss the injection power of the superior power grid, with the unit of kW; t l,t is I l at time t the current magnitude on the l r l th l branch, with the unit of kA; α c is the carbon emission treatment cost, $ / (tCO2); Etrans,t At t time t, the carbon potential of the superior power grid node is gCO2 / (kW·h); E MT,i,t is the carbon potential of the i th gas turbine unit node at time t, with the unit of gCO2 / (kW·h).

[0044] 2. Function constraints:

[0045] 1) Construct the voltage balance equation of the AC distribution system:

[0046] (2);

[0047] (3);

[0048] In equations (2) and (3): u i,t and u j,t are respectively t the square of the voltage of node i and node j at time t; r ij and r ij are respectively the resistance value and reactance value of branch ij ; P ij,t and Q ij,t are respectively t the active power and reactive power of branch ij at time t; I ij,t is t the square of the current of branch ij at time t; u i,max and u i,min are respectively the square of the maximum value and the square of the minimum value of the voltage of node i .

[0049] 2) Construct the node power balance equation of the AC distribution system:

[0050] (4);

[0051] (5);

[0052] In equations (4) and (5): v 1( j ) is the set of nodes where the power flow flows into node j ; v 2( j) is the set of nodes for the tidal current to flow out j ; P ij,t and Q ij,t are respectively t the active and reactive powers flowing through branch ij at time i , with the direction flowing from node j to node P jk,t and Q jk,t are respectively t the active and reactive powers flowing through branch jk at time j , with the direction flowing from node k ; P D,j,t and Q D,j,t are respectively t the active and reactive loads connected to node j at time P trans,j,t and Q trans,j,t are respectively t the active and reactive powers injected from the superior power grid to node j at time P MT,j,t and Q MT,j,t are respectively t the active and reactive powers injected by the gas turbine unit to node j at time P WT,j,t and Q WT,j,t are respectively t the active and reactive powers injected by the wind turbine unit to node j at time P PV,j,t and Q PV,j,t are respectively t the active and reactive powers injected by the photovoltaic unit to node j at time P ESOP,j,t and Q ESOP,j,t are respectively t the active and reactive powers injected by the ESOP to node j at time

[0053] 3) Construct the line power flow constraint in the AC distribution system:

[0054] Since the line power flow constraint is non - linear, the second - order cone relaxation method is used to transform the non - linear constraint into a linear second - order cone constraint.

[0055] (6);

[0056] 4) Construct the operation constraints of the units in the AC distribution system:

[0057] (7);

[0058] (8);

[0059] (9);

[0060] (10);

[0061] (11);

[0062] (12);

[0063] (13);

[0064] (14);

[0065] In equations (6) - (14): and are the upper and lower limits of the active power output of the superior power grid at time t respectively; and are the upper and lower limits of the active power output of the gas turbine unit at time t respectively; P max trans , i, t and P min trans , i, t are the upper and lower limits of the active power output of the superior power grid at time t respectively; P max MT , i, t and P min MT , i, t are the upper and lower limits of the active power output of the gas turbine unit at time t respectively; P max WT , i, t and P min WT , i, t are the upper and lower limits of the active power output of the wind turbine unit at time t respectively; and are the upper and lower limits of the active power output of the photovoltaic unit at time t respectively; and are the upper-level power grid t upper and lower limits of reactive power output at time and are the gas turbine units t upper and lower limits of reactive power output at time and are the wind turbine units t upper and lower limits of reactive power output at time and are the photovoltaic units t upper and lower limits of reactive power output at time P trans,i,t and Q trans,i,t are respectively t active and reactive power injected into the upper-level power grid at node i at time P MT,i,t and Q MT,i,t are respectively t active and reactive power injected into the gas turbine unit at node i at time P WT,i,t and Q WT,i,t are respectively t active and reactive power injected into the wind turbine unit at node i at time P PV,i,t and Q PV,i,t are respectively t active and reactive power injected into the photovoltaic unit at node i at time

[0066] 5) Construct the ESOP operating power constraint:

[0067] (15),

[0068] In formula (15): The two ends of the ESOP are respectively connected to node i and node j; P ESOP,i,t is the active power injected by the ESOP into node i at time t; P ESOP,j,t is the active power injected by the ESOP into node j at time t; is the active power injected by the ESOP energy storage device into the distribution network through the virtual node at time t, that is, the discharge power of the ESOP at time t; t is the active power injected by the distribution network into the ESOP energy storage device through the virtual node at time t, that is, the charging power of the ESOP at time t.

[0069] 6) Construct the ESOP operating capacity constraint:

[0070] (16);

[0071] In formula (16): Q ESOP,i,t is the reactive power injected by the ESOP into node i at time t; Q ESOP,j,t is the reactive power injected by the ESOP into node j at time t; S ESOP,i is the capacity of the ESOP connected to node i; S ESOP,j is the capacity of the ESOP connected to node j

[0072] 7) Construct the operating power loss constraint of the ESOP:

[0073] The operating efficiency of the ESOP can reach 98%. Therefore, the power loss of the ESOP is ignored in the problem of low-carbon optimal operation of the flexible distribution network.

[0074] 8) Construct the operating constraints of the ESOP energy storage device:

[0075] (17);

[0076] (18);

[0077] (19);

[0078] (20);

[0079] (21);

[0080] In formulas (17)-(21): E ESOP,0 is the stored electricity of the ESOP at the initial moment; E ESOP,T is the stored electricity of the ESOP at the last moment; is the charging state coefficient of the ESOP at time t; is the discharging state coefficient of the ESOP at time t; is the capacity of the ESOP DC converter; is the minimum storage coefficient of the ESOP; is the maximum storage coefficient of the ESOP; E ESOP,t is the stored electricity of the ESOP energy storage device at time t; is the capacity of the ESOP energy storage device; E ESOP,t+1 is the stored electricity of the ESOP at time t + 1; η ch is the charging loss coefficient of the ESOP; η dis is the discharging loss coefficient of the ESOP.

[0081] 9) Construct the node carbon potential equality constraint of the virtual node k:

[0082] In addition to the power flow and carbon flow interactions with the energy storage device of the ESOP, the virtual node k also conducts power flow and carbon flow interactions with the nodes connected to the ESOP branch.

[0083] (22);

[0084] In Equation (22): e k,t is the node carbon potential of the virtual node k at time t; P ik,t is the active power injected from the node connected to the ESOP branch to the virtual node k at time t; N + is the set of nodes connected to the ESOP branch; e i,t is the node carbon potential of the node connected to the ESOP branch at time t; is the active power output by the ESOP at time t; is the node carbon potential of the ESOP energy storage device in the discharging state at time t, and in this state, it is regarded as a low-carbon unit.

[0085] 10) Equality constraint of the node carbon potential of the ESOP energy storage device:

[0086] The ESOP energy storage device conducts power flow and carbon flow interactions with the flexible distribution network only through the virtual node k. When modeling the node carbon potential of the ESOP energy storage device, in addition to considering the differences in different operating states of the ESOP energy storage device, the time series characteristics of the energy storage device itself also need to be considered, that is, the power flow and carbon flow stored in the energy storage device have an impact on the solution of the node carbon potential at the current moment. The node carbon potential is modeled according to the operating state of the ESOP energy storage device as follows:

[0087] ① The energy storage device of the ESOP is in the offline state:

[0088] In the offline state, the energy storage device does not conduct power flow and carbon flow interactions with the flexible distribution network system. The ESOP is equivalent to a soft open point (SOP), and the branch installed between two feeders participates in the operation of the distribution network as a "branch" that allows active power to pass through and can output reactive power. In the offline state, there is no need to model the node carbon potential of the ESOP energy storage device, and its operating constraints are as follows:

[0089] (23);

[0090] ② The energy storage device of the ESOP is in the charging state:

[0091] In the charging state, the energy storage device receives power flow and carbon flow from the flexible distribution network through the virtual node k. At this time, the ESOP energy storage device is equivalent to a load node participating in the operation of the distribution network:

[0092] (24);

[0093] In formula (24): is the node carbon potential when the ESOP energy storage device is in the charging state at time t.

[0094] ③ The energy storage device of ESOP is in the discharging state:

[0095] In the discharging state, the energy storage device injects power flow and carbon flow into the flexible distribution network through the virtual node k. At this time, the ESOP energy storage device is equivalent to a low-carbon unit participating in the operation of the distribution network. And when modeling the node carbon potential of the ESOP energy storage device in the discharging state, the influence of the timing of the energy storage device on the stored electricity and the virtual carbon storage amount needs to be considered:

[0096] (25);

[0097] (26);

[0098] (27);

[0099] The ESOP stored electricity constraint is shown in formula (25), and the ESOP virtual carbon storage amount constraint is shown in formula (26). Among them, E0 is the initial stored electricity of the ESOP energy storage device; 、 are the charging and discharging powers of the ESOP energy storage device at time a respectively; C ESOP,t is the virtual carbon storage amount of the ESOP energy storage device at time t; C0 is the initial virtual carbon storage amount of the ESOP energy storage device; e k,a is the node carbon potential of the virtual node k at time a; is the node carbon potential when the ESOP energy storage device is in the discharging state at time t.

[0100] 11) Construct the carbon flow rate constraint of the ESOP branch:

[0101] (28);

[0102] In formulas (25)-(27): P ESOP,ij is the actual active power flowing from node i to node j in the ESOP branch. The nodes include the load nodes in the flexible distribution network and the virtual nodes of ESOP; E ESOP,ij is the carbon flow density of the ESOP branch; R ESOP,ij is the carbon flow rate flowing through the ESOP branch.

[0103] 12) Construct the node carbon potential equality constraint of the nodes connected by the ESOP branch:

[0104] (29);

[0105] In formula (29): l is the branch number; Ωi+ is the set of all branches where the current flows into node i; E ESOP,ij is the carbon flow density on branch ij where the ESOP is installed; E N,i is the carbon potential of node i, including the load nodes and the virtual nodes of the ESOP; P l is the active power flow of branch l; E L,l is the carbon flow density of branch l; R l is the carbon flow rate of branch l.

[0106] 13) Construct the operating constraints of the PV inverter:

[0107] (30),

[0108] (31);

[0109] (32);

[0110] In equations (30)-(32): is the upper limit of the output of the PV unit installed at node i; S PV,i is the capacity of the PV inverter installed at node i; k f is the power factor of the PV inverter.

[0111] The requirement of minimizing the carbon emission treatment cost of the flexible distribution network in the objective function ensures the low-carbon and economic performance in the low-carbon optimization operation of the flexible distribution network.

[0112] S2. Input the flexible distribution network data into the optimal power flow model of the flexible distribution network, and solve the above optimal power flow model to obtain the optimal active power flow distribution of the flexible distribution network;

[0113] The flexible distribution network data input in S2 includes unit parameters and base load parameters. The optimal power flow model of the flexible distribution network is constructed based on typical power market organizations, network operation constraints in the distribution system, operation constraints of intelligent energy storage soft switches, and operation constraints of various distributed power sources; considering factors such as the low-carbon optimization operation of the flexible distribution network, with the goal of minimizing the sum of the power purchase cost from the superior grid, the operation and maintenance cost of distributed power sources, the network loss cost, and the carbon emission cost, regarding the branch where the ESOP is installed as a "branch" through which the operating active power passes and can generate reactive power, and at the same time, the energy storage device of the ESOP participates in the power flow interaction of the distribution network and absorbs the output of new energy units, using a centralized algorithm to solve the optimal active power flow distribution of the flexible distribution network;

[0114] S3. Establish a carbon flow calculation model for the flexible distribution network, solve the carbon flow calculation model of the flexible distribution network, and calculate the charging and discharging conditions of the ESOP and the change of the virtual carbon storage, the real-time carbon flow distribution of the entire flexible distribution network, and the total carbon emissions;

[0115] The establishment of the carbon flow calculation model for the flexible distribution network in S3 includes statistically calculating the output of each unit in the flexible distribution network and the unit carbon emission intensity EG, the charging and discharging power and the real-time stored electricity of the ESOP energy storage device, the power magnitude on the line equipped with ESOP, and clarifying the power flow direction on the line equipped with ESOP; defining key matrices and vectors.

[0116] The key matrices and vectors defined in S3 include the generator set carbon emission intensity vector, the node carbon potential vector, the load carbon flow rate vector, the branch carbon flow rate distribution matrix, the branch carbon flow rate distribution matrix of the ESOP installed, the node carbon potential matrix of the ESOP energy storage device under different working conditions, and the ESOP virtual carbon storage vector.

[0117] Solving the carbon flow calculation model of the flexible distribution network in S3 to obtain the real-time carbon flow distribution and the total carbon emissions of the flexible distribution network includes: obtaining the power flow and carbon flow distribution of the entire flexible distribution network; the real-time output of the superior grid and each unit of the flexible distribution network and the total carbon emissions injected; the change of the real-time virtual carbon storage of ESOP, reflecting the role of ESOP in the consumption of clean energy, reducing the carbon emissions of the flexible distribution network, and the flexible power flow regulation ability of the distribution network.

[0118] The carbon flow calculation model of the flexible distribution network is solved using MATLAB to obtain the real-time stored electricity and real-time virtual carbon storage of ESOP, the real-time carbon flow distribution and the total carbon emissions of the flexible distribution network.

[0119] An overview of the existing carbon emission flow theory of the power system is given, the indicators of the carbon flow theory are introduced, such as the branch carbon flow rate Rl, the node carbon potential EN, etc., and the calculation method of the carbon emissions of the power system based on the carbon flow theory is introduced. Statistically calculate the active power output of each unit in the power system, the charging and discharging power of the ESOP energy storage device, and the carbon emission intensity EG of each unit. At the same time, consider the power magnitude of the line equipped with ESOP, clarify the power flow direction on the line equipped with ESOP, and define some key matrices and vectors according to the requirements of carbon emission flow solution. The key matrices and vectors defined in S3 include the generator set carbon emission intensity vector, the node carbon potential vector, the load carbon flow rate vector, and the branch carbon flow rate distribution matrix, and establish a basic calculation method for the FDN carbon emission flow considering ESOP. While attributing the carbon emissions on the power generation side to the load side, obtain the carbon flow distribution of the entire network;

[0120] Statistically analyze the active power output and carbon emission intensity EG of the superior power grid and each distributed power source in the flexible distribution network. At the same time, statistically analyze the power of the line equipped with ESOP, and the stored electricity of the energy storage device of ESOP at each time period, and clarify the physical meaning of the power flow direction on the line equipped with the intelligent flexible switch. Considering the influence of the time series of the ESOP energy storage device on the power flow and carbon flow, and the definition of carbon emission flow accounting, the energy storage device of ESOP is regarded as a newly added node in the flexible distribution network, and the node carbon potential modeling of the ESOP energy storage device is related to the working state of the energy storage device. Equivalent the connection point of the ESOP DC converter and the converter to a virtual node, and the energy storage device of ESOP participates in the power flow interaction of the distribution network through the virtual node. Combining with the carbon flow theory, obtain the carbon flow distribution RB of the whole network branches, the carbon flow rate RL of each load node, the node carbon potential ek of the ESOP virtual node, the node carbon potential EESOP of each state of the ESOP energy storage device, and the virtual carbon storage RE of the ESOP.

[0121] Assume that the FDN has N actual nodes and L virtual nodes; among the actual nodes, K nodes have generator injections and M nodes have loads.

[0122] Table 1 Power system carbon emission flow solution matrix

[0123]

[0124] 11) Generator carbon emission intensity vector:

[0125] (33);

[0126] In formula (33): E tr,t is the real-time carbon potential of the superior power grid at time t; E MT is the generator carbon emission intensity of the gas turbine unit; E WT is the generator carbon emission intensity of the wind turbine unit; E PV is the generator carbon emission intensity of the photovoltaic unit; is the generator carbon emission intensity of the ESOP energy storage device in the discharge state at time t. The ESOP energy storage device has different carbon emission characteristics with different generators in the discharge state. When the energy storage device is not in the discharge state, the corresponding generator carbon emission intensity is 0. It is a known condition in the carbon flow calculation and can form the generator carbon emission intensity vector of the system. The generator carbon emission intensity vector is a (K + L)-dimensional column vector, represented by E G to represent.

[0127] 12) Node carbon potential vector:

[0128] (34);

[0129] In Equation (34), the primary calculation objective of the carbon emission flow of the power system is the carbon potential of all nodes. The node carbon potential vector is an (N + L)-dimensional column vector, denoted by E N for representation.

[0130] 13) Branch carbon flow rate distribution matrix:

[0131] (35);

[0132] In Equation (35), after obtaining the node carbon potential, the carbon flow rate of each branch can be further obtained. Then the branch carbon flow rate distribution matrix is an (N + L)-order square matrix, denoted by R B for representation.

[0133] 14) Load carbon flow rate vector:

[0134] (36);

[0135] In Equation (36), the carbon emission intensity of electricity consumption of the node load is equal to the carbon potential of the node. Based on the load distribution matrix, the carbon flow rate corresponding to the load can be obtained, denoted by RL.

[0136] Through the above matrices and vectors, a carbon flow calculation model of the flexible distribution network is established, and MATLAB is used for solution to obtain the carbon flow distribution and total carbon emission of the flexible distribution network.

[0137] S4. Adjust the carbon emission flow in the flexible distribution network according to the calculation results of the real-time carbon flow distribution and total carbon emission of the entire flexible distribution network obtained in step S3, so as to minimize the objective function in the optimal power flow model. Based on the ESOP's own energy storage and regulation functions, combined with the calculated real-time stored electricity and virtual carbon storage of the ESOP, verify that the ESOP absorbs the output of clean energy, reduces the carbon emission of the flexible distribution network system, and flexibly regulates the power flow and carbon emission flow of the flexible distribution network in real time, so that the power flow distribution of the flexible distribution network conforms to the optimal active power flow distribution, and the flexible distribution network operates optimally.

[0138] In S4, the carbon emission flow in the flexible distribution network is specifically adjusted through the ESOP branch. At the same time, the ESOP energy storage device stores clean energy when the light is sufficient, improves the absorption of clean energy, and emits low-carbon energy during the period when the superior power grid injects high-carbon energy into the flexible distribution network to reduce the carbon emission consumption of the distribution network and improve the carbon reduction ability of the flexible distribution network.

[0139] The present invention can quickly and accurately solve the carbon flow distribution of the entire power grid, the regulation effect of the ESOP on the power flow and carbon flow, and the carbon emission storage effect of the ESOP when the flexible distribution network operates with low-carbon optimization. In summary, the embodiments of the present invention can quickly and accurately solve the carbon emission flow distribution of the entire FDN when the flexible distribution network with ESOP operates with low-carbon optimization.

[0140] The present invention relates to the related research on the calculation of carbon emission flow in a flexible distribution network considering intelligent energy storage soft switches. Considering the functional characteristics of ESOP, the branch with ESOP installed is equivalent to an almost lossless "branch", and at the same time, the connection point between the DC converter and the inverter in ESOP is equivalent to a virtual node to participate in the operation of the distribution system, which is convenient for the priority consumption of clean energy. At the same time, considering the low-carbon optimal operation of the flexible distribution network, an optimal power flow model of the flexible distribution network is established to obtain the optimal power flow distribution of the flexible distribution network; based on the carbon emission flow theory and combined with the operation characteristics of ESOP and the energy storage characteristics, a carbon flow calculation model of the flexible distribution network considering intelligent energy storage soft switches is constructed, which can quickly and accurately solve the power flow distribution and carbon emission flow distribution of the whole network during the low-carbon optimal operation of the flexible distribution network, can calculate the carbon flow distribution of the flexible distribution network in real time, and the ESOP in the flexible distribution network adjusts the carbon flow distribution of the flexible distribution network to minimize the target cost in the flexible distribution network and realize the low-carbon and economic operation of the flexible distribution network.

[0141] The feasibility of the solution in the above embodiments is verified by specific experiments as described in detail below:

[0142] Table 2 Distributed Generation Parameters

[0143]

[0144] Figure 4 shows the topological structure of the FDN selected for the experiment. Among them, the load curves of each time period of the FDN load nodes are as Figure 5 shown; the daily output time series characteristic curves of the WT and PV units connected to the FDN are as Figure 6 shown; the real-time electricity price and real-time carbon potential change conditions of the upstream power grid are respectively as Figure 7 , Figure 8 shown.

[0145] Figure 9It shows the daily output of each unit in the FDN. Considering the output characteristics of the MT unit, WT unit, and PV unit, among them, the output of the MT unit is stable, but its output will cause carbon emissions; the output of the WT unit changes in real time, and its injection power is relatively low; the output of the PV unit is 0 in the absence of light, and the output increases with the increase of light intensity. At the same time, the output of each unit also takes into account the real-time electricity price of the superior power grid and the operation and maintenance costs of each distributed unit to minimize the electricity purchase cost. As shown at time 11, at this time, the light intensity is high, the PV unit is fully loaded, the wind speed is relatively high, and the output of the WT unit is large. The operation and maintenance cost of the MT unit is much lower than the cost of purchasing electricity from the superior power grid. Since the FDN preferentially absorbs the output of new energy units, and the PV unit and WT unit do not produce carbon emissions, the carbon emission intensity of the MT unit is lower than that of the superior power grid, effectively reducing the carbon emissions in the system. At the same time, the output of each unit also considers the economic cost in this period, and achieves the goal of reducing the system carbon emissions under the condition of minimizing the cost.

[0146] Figure 10 It shows the power flow situation on the branch where the ESOP is installed and the charge and discharge situation of the ESOP energy storage device. PSOP-6 is the power flow of the branch connecting the ESOP and node 6, and its positive power flow direction is from the ESOP to node 6; PSOP-15 is the power flow of the branch connecting the ESOP and node 15, and its positive power flow direction is from the ESOP to node 15; PESOP-ESS is the charge and discharge power of the ESOP energy storage device, and its positive power flow direction is the charging power, and the negative direction is the discharging power. From 0 to 4 o'clock, the light intensity is 0, and only the wind power is operating. At this time, the branch where node 6 is located has a large demand for power flow. Considering the low loss of the ESOP branch transmission power, the power flow in the FDN flows from node 15 to node 6; as the light intensity increases, the output of the photovoltaic unit increases, and the clean energy flows from node 15 to node 6 through the ESOP branch. At the same time, the ESOP energy storage device stores the clean energy, playing a role in reducing carbon, reducing network losses, and absorbing the output of new energy.

[0147] The FDN has N (N = 15) actual nodes and L (L = 1) virtual node. Among the actual nodes, K (K = 5) nodes have generator power injection, and M (M = 13) nodes have loads. Node 1 is connected to the superior power grid, and its carbon emission intensity changes in real time; Node 5 is connected to the MT unit, and its carbon emission intensity is relatively high, and its operation and maintenance cost is higher than that of the WT and PV units; Node 9 is connected to the WT unit, and Nodes 11 and 14 are connected to the PV units, and their carbon emission intensities are both 0. After completing the optimal power flow calculation, data such as the injection power of the superior power grid and each unit, the injection power of each node, the power flow of each branch, and the load power of each node are required for the calculation of the carbon emission flow.

[0148] Starting from the superior power grid and each distributed unit, calculate the carbon potential of all nodes one by one according to the power flow direction. When the FDN operates with low-carbon optimization, from the solution results of step 202, it can be seen that the branch equipped with ESOP is equivalent to a "branch" that allows active power to pass through and can generate reactive power. Regarding the energy storage device of ESOP as a newly added node in the flexible distribution network, considering the working state of the energy storage device and the power flow-carbon flow coupling relationship, for different operating states of the ESOP energy storage device, corresponding node carbon potential modeling is carried out. And the connection point between the DC converter and the inverter of ESOP is equivalent to a virtual node. The energy storage device of ESOP participates in the interaction of power flow and carbon flow in the distribution network through the virtual node. The operating state of the ESOP energy storage device affects the operating state of the virtual node. Select summer as the typical day. Taking t = 11 as an example, at this time, the sunlight is sufficient, the PV unit is fully loaded, the output of the WT unit is low, and both the MT unit and the superior power grid have output. Calculate the carbon emission flow of FDN, and the node carbon potentials of each node of FDN are obtained as shown in Table 3.

[0149] Table 3 Node Carbon Potentials of Each Node in the Flexible Distribution Network

[0150]

[0151] As can be seen from Table 3, when t = 11, the PV unit is fully loaded, and both the WT and MT units are outputting, providing clean energy for FDN. Since the flexible distribution network is a radial network, the carbon potential of the node connected to the superior power grid will be affected by the carbon emission intensity of the units in the superior power grid. Downstream of this node, if there are no other distributed units, the carbon potentials of all other downstream nodes will be equal to the carbon potential of this node. Therefore, in FDN, the node carbon potentials of some adjacent nodes are the same. The node carbon potentials of the nodes downstream of the node connected to the superior power grid that are not affected by other new energy units are the same as the carbon emission intensity of the units in the superior power grid. Among them, the loads of nodes 9 and 11 are relatively large. Although the outputs of the connected WT and PV units cannot meet the load demands of the nodes and still require power supply from the superior power grid, the new energy units have the effect of reducing the node carbon potentials of the load nodes, making the node carbon potentials of the above nodes much smaller than the node carbon potential of the superior power grid node. The branch equipped with ESOP connects node 6 and node 15. At this moment, the light intensity is the largest, and the photovoltaic unit installed at node 14 is fully loaded. The low-carbon energy flows from node 15 to node 6 through the ESOP branch. At this time, the ESOP energy storage device also injects clean energy into FDN to meet the load demand of node 6 and reduce the node carbon potentials of the above nodes, realizing the low-carbon operation of FDN. Further calculate the carbon flow rate vector and distribution matrix flowing out of the node, so as to obtain the carbon flow rate of each branch in the whole network and the carbon flow rate of each node load as Figure 11 shown.

[0152] The carbon flow rate injected into the entire network is roughly equal to the carbon flow rate flowing out of the entire network, verifying the conservation of the carbon emission flow. The above analyses are all carried out at a certain time section. This method can be used to accurately solve the carbon potential of each node, the load carbon flow rate, the carbon emission distribution of the ESOP branch, and the carbon flow rate distribution on the branch at a certain moment in the FDN. The flow of the carbon emission flow in the entire network is also clearly shown, which helps to further study the low-carbon optimal operation of the FDN and realize the optimal operation of the flexible distribution network.

[0153] Those skilled in the art can understand that the drawings are only schematic diagrams of a preferred embodiment. The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0154] The above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for optimizing the operation of a flexible distribution network taking into account intelligent energy storage soft switches, characterized in that: The following steps are involved: S1. Based on the power flow control capability and energy storage characteristics of the smart energy storage soft switch (ESOP), the optimal power flow model of the flexible distribution network with ESOP installed is established, and the objective function and function constraints of the optimal power flow model are constructed; Function constraints include: voltage balance equation of AC distribution system, power balance equation of AC distribution system node, line flow constraint in AC distribution system, unit operation constraint of AC distribution system, ESOP operation power constraint, ESOP operation capacity constraint, ESOP operation power loss constraint, ESOP energy storage device operation constraint, ESOP storage capacity constraint, ESOP virtual carbon storage constraint, node carbon potential equation constraint of virtual node k, node carbon potential equation constraint of ESOP energy storage device, ESOP branch carbon flow rate constraint, node carbon potential equation constraint of ESOP branch connection node, photovoltaic inverter operation constraint S2, inputting the flexible distribution network data into the optimal power flow model of the flexible distribution network, solving the optimal power flow model to obtain the optimal active power flow distribution of the flexible distribution network; S3. Establish a carbon flow calculation model for the flexible distribution network, solve the carbon flow calculation model for the flexible distribution network, calculate the ESOP charging and discharging conditions and the change of virtual carbon storage, the real-time carbon flow distribution of the flexible distribution network, and the total carbon emissions; S4. According to the real-time carbon flow distribution of the entire flexible distribution network and the total carbon emission calculation results calculated in step S3, the carbon emission flow in the flexible distribution network is adjusted to minimize the objective function in the optimal power flow model. Based on the ESOP's own energy storage and regulation functions, combined with the calculated ESOP real-time power storage and virtual carbon storage, the ESOP's clean energy output is verified to reduce the carbon emissions of the flexible distribution network system. The flexible distribution network power flow and carbon emission flow are flexibly regulated in real time. The power flow distribution of the flexible distribution network conforms to the optimal active power flow distribution, so that the flexible distribution network operates optimally.

2. The method for optimizing the operation of a flexible distribution network taking into account intelligent energy storage soft switches according to claim 1, characterized in that: The objective function in S1 aims to minimize the sum of the cost of purchasing electricity from the superior power grid, the operation and maintenance cost of each distributed power source, the network loss cost and the carbon emission treatment cost.

3. The method for optimizing the operation of a flexible distribution network taking into account intelligent energy storage soft switches according to claim 2, characterized in that: In the flexible distribution network with ESOP installed, the branch with ESOP installed is regarded as a branch that runs active power and can generate reactive power. The energy storage device of ESOP is regarded as a newly added node in the flexible distribution network, and the connection point between the DC converter and the inverter in ESOP is equivalent to a virtual node. The ESOP energy storage device participates in the distribution network flow and carbon flow interaction through the virtual node. The real-time storage capacity and virtual carbon storage of the ESOP energy storage device are calculated to verify the effect of ESOP on clean energy consumption, reducing carbon emissions of flexible distribution networks and the flexible regulation capability of distribution network flow.

4. The method for optimizing the operation of a flexible distribution network taking into account intelligent energy storage soft switches according to claim 1, characterized in that: The flexible distribution network data input in S2 includes unit parameters and basic load parameters.

5. The method for optimizing operation of a flexible distribution network taking into account intelligent energy storage soft switches according to claim 1, characterized in that: The carbon flow calculation model of the flexible distribution network established in S3 includes statistics on the output of each unit in the flexible distribution network and the carbon emission intensity EG of the unit, the charging and discharging power and real-time storage capacity of the ESOP energy storage device, the power size on the line equipped with ESOP, and clearly defines the power flow direction on the line equipped with ESOP; defines key matrices and vectors.

6. The method for optimizing the operation of a flexible distribution network taking into account intelligent energy storage soft switches according to claim 5, characterized in that: The key matrices and vectors defined in S3 include the carbon emission intensity vector of the generator set, the node carbon potential vector, the load carbon flow rate vector, the branch carbon flow rate distribution matrix, the installed ESOP branch carbon flow rate distribution matrix, the node carbon potential matrix of the ESOP energy storage device under different working conditions, and the ESOP virtual carbon storage vector.

7. The method for optimizing the operation of a flexible distribution network taking into account intelligent energy storage soft switches according to claim 6, characterized in that: The carbon flow calculation model of the flexible distribution network is solved using MATLAB to obtain the real-time electricity storage capacity and real-time virtual carbon storage capacity of ESOP, the real-time carbon flow distribution of the flexible distribution network, and the total carbon emissions.

8. The method for optimizing operation of a flexible distribution network taking into account intelligent energy storage soft switches according to claim 7, characterized in that: The carbon flow calculation model of the flexible distribution network is solved in S3 to obtain the real-time carbon flow distribution and total carbon emissions of the flexible distribution network, including: obtaining the power flow and carbon flow distribution of the entire flexible distribution network; the real-time output and total injected carbon emissions of the upper-level power grid and each unit of the flexible distribution network; the real-time changes in the virtual carbon storage of ESOP, which reflects the role of ESOP in absorbing clean energy, reducing carbon emissions of the flexible distribution network, and the flexible power flow regulation capabilities of the distribution network.

9. The method for optimizing the operation of a flexible distribution network taking into account intelligent energy storage soft switches according to claim 8, characterized in that: In S4, the carbon emission flow in the flexible distribution network is adjusted specifically through the ESOP branch. At the same time, the ESOP energy storage device stores clean energy when there is sufficient sunlight, improves the clean energy consumption, and injects high-carbon energy into the flexible distribution network during the period of high-carbon energy injection from the upper power grid, emits low-carbon energy to reduce the carbon emission consumption of the distribution network, and improves the carbon reduction capacity of the flexible distribution network.

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