Transmission and distribution collaborative double-layer economic dispatching method, system, equipment and medium

Abstract

The invention belongs to the technical field of power grid resource optimization scheduling, and discloses a transmission and distribution collaborative double-layer economic scheduling method, system, equipment and medium, and the method comprises the steps: constructing a transmission and distribution power grid layered scheduling frame based on the operation characteristics and source load characteristics of a transmission and distribution power grid, and carrying out the resource scheduling of the transmission and distribution power grid according to the resource scheduling of the transmission and distribution power grid; configuring an operation mode of hierarchical scheduling of the power transmission and distribution network; based on transmission and distribution coupling characteristics of the power transmission and distribution network, inter-layer decoupling variables of the power transmission and distribution network are set, a consistency criterion is constructed in combination with a physical structure of the power transmission and distribution network, and convergence of the power transmission and distribution network is checked; and setting an objective function and constraint conditions of the power transmission and distribution network, constructing a power transmission and distribution network economic dispatching model, and optimizing and updating model parameters of the economic dispatching model in combination with the execution result of the power transmission and distribution network. A real-time double-layer economic dispatching model is built, an original power transmission and distribution network integrated optimization model is converted into a power transmission and distribution network layered optimization model, support is provided for high-proportion resources in a distribution network to participate in regulation and control, and the joint optimization duration is shortened.

Description

Technical Field

[0001] The present invention relates to the technical field of power grid resource optimization and dispatching, and in particular to a transmission and distribution coordinated double-layer economic dispatching method, system, equipment and medium. Background Art

[0002] The distribution system is a key link connecting the transmission network and the load terminal. The distribution system will gradually develop into a hub platform that supports the large-scale access and coordinated operation of power electronic power sources / loads / equipment such as distributed new energy, electric vehicle charging and swapping stations, and electrified rail transit, and plays the role of "clean substitution" on the power side and "electric energy substitution" on the load side. The large-scale access of distributed power sources and impact loads such as electric vehicles and rail transit has significantly deepened the degree of power electronics in the distribution system, increased uncertainty, and made the bidirectional power flow characteristics more prominent.

[0003] As the proportion of renewable energy in the power grid continues to increase, the operating status of the distribution network is changing, and the power generation form has changed from the output of synchronous units in the transmission network to the coordinated power generation of traditional units in the transmission network and renewable energy in the distribution network. The changes in transmission and distribution power are becoming more complex. In order to achieve the optimal economic dispatch under the new background, the centralized control of the transmission network is gradually shifting to the coordinated operation of power grids at all levels under the multi-level and extensive intelligent foundation. The implementation of hierarchical transmission and distribution coordinated economic dispatch has become an inevitable trend.

[0004] Through the above analysis, the problems and defects of the prior art are as follows:

[0005] (1) It is difficult for existing technologies to directly participate in the optimization and dispatching of active distribution networks as an independent entity. If the solution is directly obtained, it may lead to problems such as the explosion of the dimension of decision variables and difficulty in converging the solution results.

[0006] (2) Most traditional clustering algorithms have poor reliability and convergence when applied in the field of power systems. There is little research on the clustering of distributed resources that serve the optimal scheduling of distribution networks, which makes actual scheduling lack of reference and is not conducive to the optimal scheduling of regulatory resources.

[0007] Therefore, how to provide a transmission and distribution coordinated double-layer economic dispatch method, system, equipment and medium is a problem that needs to be solved urgently. Summary of the invention

[0008] The embodiments of the present invention provide a transmission and distribution coordinated double-layer economic dispatch method, system, device and medium to solve the above-mentioned technical problems existing in the prior art.

[0009] In order to have a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. This summary is not intended to be a general review, nor is it intended to identify key / important components or to delineate the scope of protection of these embodiments. Its only purpose is to present some concepts in a simple form as a preface to the detailed description that follows.

[0010] According to a first aspect of an embodiment of the present invention, a transmission and distribution coordinated double-layer economic dispatch method is provided.

[0011] In one embodiment, the transmission and distribution coordinated dual-layer economic dispatch method includes:

[0012] Based on the operation characteristics and source-load characteristics of the transmission and distribution network, a hierarchical dispatching framework for the transmission and distribution network is constructed, and the operation mode of the hierarchical dispatching of the transmission and distribution network is configured according to the resource dispatching of the transmission and distribution network;

[0013] Based on the transmission and distribution coupling characteristics of the transmission and distribution network, the inter-layer decoupling variables of the transmission and distribution network are set, and combined with the physical structure of the transmission and distribution network, a consistency criterion is constructed to verify the convergence of the transmission and distribution network;

[0014] The objective function and constraints of the transmission and distribution network are set, the economic dispatch model of the transmission and distribution network is constructed, and the model parameters of the economic dispatch model are optimized and updated based on the execution results of the transmission and distribution network.

[0015] In one embodiment, the construction of a transmission and distribution network hierarchical scheduling framework based on the operation characteristics and source-load characteristics of the transmission and distribution network, and the configuration of the operation mode of the transmission and distribution network hierarchical scheduling according to the resource scheduling of the transmission and distribution network include:

[0016] Obtain the electrical behavior of the transmission and distribution network during the power transmission and distribution process, classify the power grids with voltage levels greater than a preset voltage threshold and that are responsible for power supply into the transmission network layer, and allocate the adjustable resources of the transmission network layer based on the dynamic characteristics of the power generation sources and loads in the transmission network layer;

[0017] Classify the power grid whose voltage level is less than the preset voltage threshold and bears the power consumption function into the distribution network layer, and allocate the adjustable resources of the distribution network layer based on the dynamic characteristics of the power generation source and the load in the distribution network layer;

[0018] Based on the adjustable resources of the transmission network layer and the distribution network layer, the operation mode of power self-consistency and information interaction between layers in the control layer is set, and the transmission network layer and the distribution network layer are driven to operate according to the operation mode.

[0019] In one embodiment, the operation mode includes an intra-layer power self-consistent mode and an inter-layer information interaction mode;

[0020] The intra-layer power self-consistent mode is that the output power of the thermal power units in the transmission network layer is equal to the sum of the transmission network load power and the transmission network layer interaction power, and the sum of the distribution network layer interaction power and the photovoltaic output in the distribution network layer is equal to the sum of the distribution network load power and the energy storage system output;

[0021] The inter-layer information interaction is that the transmission network layer submits the supported active power output to the distribution network layer, and the distribution network layer submits the required active power output to the transmission network layer.

[0022] In one embodiment, the inter-layer decoupling variables of the transmission and distribution network are set based on the transmission and distribution coupling characteristics of the transmission and distribution network, and a consistency criterion is constructed in combination with the physical structure of the transmission and distribution network to verify the convergence of the transmission and distribution network, including:

[0023] The coupled interactive power between the transmission network layer and the distribution network layer is set as a shared variable. When the transmission network layer performs optimization, the interactive power is set as an equivalent load to participate in the optimization. When the distribution network layer performs optimization, the interactive power is set as an equivalent generator to participate in the optimization.

[0024] Based on the relationship between the difference in interaction power between the distribution network layer and the transmission network layer and the preset power threshold, a consistency criterion is constructed. When the optimization of the distribution network layer or the transmission network layer is completed, it is checked whether the transmission power of the distribution network layer or the transmission network layer meets the consistency criterion and whether the optimization result converges.

[0025] In one embodiment, the calculation formula of the consistency criterion is:

[0026]

[0027] In the formula, The transmission network delivers power to the distribution network during the transmission network layer dispatching; is the active power purchased by the distribution network from the transmission network during the distribution network layer dispatch; ε is the convergence accuracy of the two-layer model.

[0028] In one embodiment, the objective function and constraint conditions of the transmission and distribution network are set, the economic dispatch model of the transmission and distribution network is constructed, and the model parameters of the economic dispatch model are optimized and updated in combination with the execution results of the transmission and distribution network, including:

[0029] Set the dispatching cycle of the transmission and distribution network. Within the dispatching cycle, take the lowest operating cost of thermal power units as the optimization goal, combine the transmission and distribution consistency goal, set the constraints and objective function of the transmission network layer, and establish the economic dispatching model of the transmission network layer.

[0030] In the dispatching cycle, taking the comprehensive economic optimization as the optimization goal, combined with the transmission and distribution consistency goal, the constraints and objective functions of the distribution network layer are set, and the economic dispatching model of the distribution network layer is established;

[0031] Obtain the optimization execution results of the transmission network layer and the distribution network layer, exchange the optimized power information of the transmission network layer and the distribution network layer, and determine whether the number of iterations, iteration accuracy and consistency indicators meet the requirements. If they meet the requirements, output the optimization results of the transmission and distribution network. If they do not meet the requirements, update the algorithm multiplier and call the economic dispatch model of the transmission network layer and the distribution network layer for re-optimization.

[0032] In one embodiment, the objective function of the transmission network layer is:

[0033]

[0034] In the formula, F TN is the total objective function of the transmission network layer; is the active output of the i-th generator at time t; c0, c1, c2 are the constant term, first-order term coefficient and second-order term coefficient of the unit output cost respectively; v and w are the correction coefficients in the consistency target; N G is the total number of traditional units, T is the total scheduling cycle; The transmission network delivers power to the distribution network during the transmission network layer dispatching; It is the transmission power demand for the transmission network after the transmission network layer scheduling is completed.

[0035] In one embodiment, the objective function of the distribution network layer is:

[0036]

[0037] In the formula, F DN is the total objective function of the distribution network layer; are the energy storage charging and discharging power of distribution network node i at time t; c ess 、c b are the unit operating cost of energy storage and the unit power purchase cost of the upper grid respectively; v and w are the correction coefficients in the consistency target; N ess is the total number of PV and energy storage nodes; Δt is the scheduling period; It is the transmission power received by the distribution network from the transmission network during the dispatching of the distribution network layer; It is the transmission power received from the transmission network after the distribution network layer scheduling is completed.

[0038] In one embodiment, the calculation formula of the algorithm multiplier is:

[0039]

[0040] Where γ is the algorithm multiplier update coefficient; v i 、w i are the correction coefficients in the consistency target of the i-th generation; v i+1 、w i+1are the correction coefficients in the consistency target of the i+1th generation; It is the transmission power received from the transmission network after the distribution network layer dispatch is completed; It is the power demand for the transmission network after the distribution network layer scheduling is completed.

[0041] According to a second aspect of an embodiment of the present invention, a transmission and distribution coordinated two-tier economic dispatch system is provided.

[0042] In one embodiment, the transmission and distribution coordinated two-tier economic dispatch system includes:

[0043] The hierarchical dispatching module is used to construct a hierarchical dispatching framework for the transmission and distribution network based on the operation characteristics and source-load characteristics of the transmission and distribution network, and configure the operation mode of the hierarchical dispatching of the transmission and distribution network according to the resource dispatching of the transmission and distribution network;

[0044] The coupling verification module is used to set the inter-layer decoupling variables of the transmission and distribution network based on the transmission and distribution coupling characteristics of the transmission and distribution network, and to build a consistency criterion in combination with the physical structure of the transmission and distribution network to verify the convergence of the transmission and distribution network;

[0045] The dispatch optimization module is used to set the objective function and constraints of the transmission and distribution network, build the economic dispatch model of the transmission and distribution network, and optimize and update the model parameters of the economic dispatch model based on the execution results of the transmission and distribution network.

[0046] In one embodiment, the hierarchical scheduling module includes: a transmission network layer module, a distribution network layer module and an operation interaction module, wherein:

[0047] The transmission network layer module is used to obtain the electrical behavior of the transmission and distribution network during the power transmission and distribution process, classify the power grids with voltage levels greater than a preset voltage threshold and that are responsible for power supply into the transmission network layer, and allocate the adjustable resources of the transmission network layer based on the dynamic characteristics of the power generation sources and loads in the transmission network layer;

[0048] The distribution network layer module is used to classify the power grids with voltage levels less than a preset voltage threshold and that consume electricity into the distribution network layer, and allocate the adjustable resources of the distribution network layer based on the dynamic characteristics of the power generation sources and loads in the distribution network layer;

[0049] The operation interaction module is used to set the operation mode of power self-consistency and inter-layer information interaction within the control layer based on the adjustable resources of the transmission network layer and the distribution network layer, and drive the transmission network layer and the distribution network layer to operate according to the operation mode.

[0050] In one embodiment, the operation mode includes an intra-layer power self-consistent mode and an inter-layer information interaction mode;

[0051] The intra-layer power self-consistent mode is that the output power of the thermal power units in the transmission network layer is equal to the sum of the transmission network load power and the transmission network layer interaction power, and the sum of the distribution network layer interaction power and the photovoltaic output in the distribution network layer is equal to the sum of the distribution network load power and the energy storage system output;

[0052] The inter-layer information interaction is that the transmission network layer submits the supported active power output to the distribution network layer, and the distribution network layer submits the required active power output to the transmission network layer.

[0053] In one embodiment, the coupling verification module includes: an equivalent sharing module and a convergence verification module, wherein

[0054] The equivalent sharing module is used to set the coupled interactive power between the transmission network layer and the distribution network layer as a shared variable. When the transmission network layer performs optimization, the interactive power is set as an equivalent load to participate in the optimization. When the distribution network layer performs optimization, the interactive power is set as an equivalent generator to participate in the optimization.

[0055] The convergence verification module is used to construct a consistency criterion based on the relationship between the difference in interaction power between the distribution network layer and the transmission network layer and a preset power threshold. When the optimization of the distribution network layer or the transmission network layer is completed, it is used to check whether the transmission power of the distribution network layer or the transmission network layer meets the consistency criterion and determine whether the optimization result converges.

[0056] In one embodiment, the scheduling optimization module includes: a transmission network scheduling module, a distribution network scheduling module and a model optimization module, wherein:

[0057] The transmission network dispatching module is used to set the dispatching period of the transmission and distribution network. Within the dispatching period, the lowest operating cost of the thermal power units is taken as the optimization goal. In combination with the transmission and distribution consistency goal, the constraints and objective functions of the transmission network layer are set, and the economic dispatching model of the transmission network layer is established.

[0058] The distribution network layer scheduling module is used to set the constraints and objective functions of the distribution network layer and establish the economic scheduling model of the distribution network layer within the scheduling period, taking the comprehensive economic optimization as the optimization goal, combining the transmission and distribution consistency goal;

[0059] The model optimization module is used to obtain the optimization execution results of the transmission network layer and the distribution network layer, exchange the power information of the optimized transmission network layer and the distribution network layer, and determine whether the number of iterations, iteration accuracy and consistency indicators meet the requirements. If the requirements are met, the optimization results of the transmission and distribution network are output; if not, the algorithm multiplier is updated, and the economic dispatch model of the transmission network layer and the distribution network layer is called for re-optimization.

[0060] According to a third aspect of an embodiment of the present invention, a computer device is provided.

[0061] In some embodiments, the computer device includes a memory and a processor, the memory stores a computer program, and the processor implements the steps of the above method when executing the computer program.

[0062] According to a fourth aspect of embodiments of the present invention, a computer-readable storage medium is provided.

[0063] In one embodiment, the computer-readable storage medium stores a computer program, and the computer program implements the steps of the above method when executed by a processor.

[0064] The technical solution provided by the embodiment of the present invention may include the following beneficial effects: the present invention is applied to the coordinated dispatching of transmission and distribution, builds a real-time two-layer economic dispatching model, converts the original integrated optimization model of the transmission and distribution network into a hierarchical optimization model of the transmission and distribution network, provides support for the participation of a high proportion of resources in the distribution network in regulation, further reduces the joint optimization time of the transmission and distribution network, and has the comprehensive advantages of being more economical, fast, and easy to dispatch in meeting the real-time regulation needs compared to traditional methods. The technical solution of the present invention fills the technical gap in the industry at home and abroad: as the scale of the transmission and distribution network expands and the topology becomes increasingly complex, the amount of calculation of the centralized optimization model will increase significantly, which may lead to low calculation efficiency, especially when the power grid undergoes real-time changes, the centralized optimization model may be difficult to respond quickly. The present invention can more effectively dispatch and utilize the resources in the power grid, including distributed power sources and controllable loads, through the coordination of the transmission network and the distribution network, thereby improving the operation efficiency of the overall power grid and optimizing the resource allocation of the transmission and distribution network.

[0065] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0067] Figure 1 is a flow chart of a transmission and distribution coordinated double-layer economic dispatch method according to an exemplary embodiment;

[0068] Figure 2 is a structural schematic diagram of a transmission and distribution coordinated double-layer economic dispatch system according to an exemplary embodiment;

[0069] Figure 3 is a schematic diagram of the structure of a computer device according to an exemplary embodiment;

[0070] Figure 4 is a schematic diagram of a hierarchical scheduling framework according to an exemplary embodiment;

[0071] Figure 5 is a schematic diagram of a transmission and distribution network layer decoupling mechanism according to an exemplary embodiment;

[0072] Figure 6 is an iterative flow chart of an economic dispatch model according to an exemplary embodiment;

[0073] Figure 7 is one of the topological diagrams of the IEEE6+IEEE33-node power transmission and distribution system according to an exemplary embodiment;

[0074] Figure 8 The second topology diagram of the IEEE6+IEEE33 node power transmission and distribution system according to an exemplary embodiment is shown;

[0075] Fig. 9 is one of the schematic diagrams of source-load characteristics of a power transmission and distribution system according to an exemplary embodiment;

[0076] Fig.10 is a second schematic diagram of source-load characteristics of a power transmission and distribution system according to an exemplary embodiment;

[0077] Fig.11 is a third schematic diagram of source-load characteristics of a power transmission and distribution system according to an exemplary embodiment;

[0078] Fig.12 is a graph showing the number of model iterations according to an exemplary embodiment;

[0079] Fig.13 is a transmission and distribution network interaction power curve diagram according to an exemplary embodiment;

[0080] Fig.14 The figure is a power distribution network source-load-storage power curve diagram according to an exemplary embodiment. DETAILED DESCRIPTION

[0081] It should be understood that, although the various steps in the flow chart are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear description in this article, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the figure may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these sub-steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0082] Each module in the device or system of the present application can be implemented in whole or in part by software, hardware, or a combination thereof. The above modules can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a memory in a computer device in the form of software, so that the processor can call and execute operations corresponding to the above modules.

[0083] In the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0084] Figure 1 An embodiment of a transmission and distribution coordinated double-layer economic dispatch method of the present invention is shown.

[0085] In this optional embodiment, the transmission and distribution coordinated double-layer economic dispatch method includes:

[0086] Step S101: Based on the operation characteristics and source-load characteristics of the transmission and distribution network, a hierarchical dispatching framework of the transmission and distribution network is constructed, and according to the resource dispatching of the transmission and distribution network, an operation mode of the hierarchical dispatching of the transmission and distribution network is configured;

[0087] Step S103: based on the transmission and distribution coupling characteristics of the transmission and distribution network, set the inter-layer decoupling variables of the transmission and distribution network, and build a consistency criterion in combination with the physical structure of the transmission and distribution network to check the convergence of the transmission and distribution network;

[0088] Step S105: set the objective function and constraint conditions of the transmission and distribution network, construct an economic dispatch model of the transmission and distribution network, and optimize and update the model parameters of the economic dispatch model in combination with the execution results of the transmission and distribution network.

[0089] In this optional embodiment, when constructing a hierarchical scheduling framework for the transmission and distribution network based on the operating characteristics and source-load characteristics of the transmission and distribution network, and configuring the operating mode of the hierarchical scheduling of the transmission and distribution network according to the resource scheduling of the transmission network and the distribution network, the electrical behavior of the transmission and distribution network in the process of power transmission and distribution can be obtained, and the power grid with a voltage level greater than a preset voltage threshold and which performs the power supply function can be divided into the transmission network layer, and based on the dynamic characteristics of the power generation source and the load in the transmission network layer, the adjustable resources of the transmission network layer are allocated; the power grid with a voltage level less than the preset voltage threshold and which performs the power consumption function can be divided into the distribution network layer, and based on the dynamic characteristics of the power generation source and the load in the distribution network layer, the adjustable resources of the distribution network layer are allocated; based on the adjustable resources of the transmission network layer and the distribution network layer, the operating mode of power self-consistency and inter-layer information interaction in the control layer is set, and the transmission network layer and the distribution network layer are driven to operate according to the operating mode.

[0090] In this optional embodiment, the operating mode includes an intra-layer power self-consistent mode and an inter-layer information interaction mode; the intra-layer power self-consistent mode is that the output power of the thermal power units in the transmission network layer is equal to the sum of the transmission network load power and the transmission network layer interaction power, and the sum of the distribution network layer interaction power and the photovoltaic output in the distribution network layer is equal to the sum of the distribution network load power and the energy storage system output; the inter-layer information interaction is that the transmission network layer submits the supportable active output to the distribution network layer, and the distribution network layer submits the required active output to the transmission network layer.

[0091] In this optional embodiment, when setting the inter-layer decoupling variables of the transmission and distribution network based on the transmission and distribution coupling characteristics of the transmission and distribution network, and constructing a consistency criterion in combination with the physical structure of the transmission and distribution network to check the convergence of the transmission and distribution network, the coupled interactive power between the transmission network layer and the distribution network layer can be set as a shared variable, and when the transmission network layer performs optimization, the interactive power is set as an equivalent load to participate in the optimization, and when the distribution network layer performs optimization, the interactive power is set as an equivalent generator to participate in the optimization; based on the relationship between the difference between the interactive power of the distribution network layer and the transmission network layer and a preset power threshold, a consistency criterion is constructed, and when the distribution network layer or the transmission network layer is optimized, it is checked whether the transmission power of the distribution network layer or the transmission network layer meets the consistency criterion, and whether the optimization result converges.

[0092] In this optional embodiment, the calculation formula of the consistency criterion is:

[0093]

[0094] In the formula, The transmission network delivers power to the distribution network during the transmission network layer dispatching; is the active power purchased by the distribution network from the transmission network during the distribution network layer dispatch; ε is the convergence accuracy of the two-layer model.

[0095] In this optional embodiment, when setting the objective function and constraints of the transmission and distribution network, constructing the economic dispatch model of the transmission and distribution network, and optimizing and updating the model parameters of the economic dispatch model in combination with the execution results of the transmission and distribution network, the dispatch cycle of the transmission and distribution network can be set. Within the dispatch cycle, the lowest operating cost of the thermal power units is taken as the optimization goal, and the transmission and distribution consistency goal is combined to set the constraints and objective functions of the transmission network layer to establish the economic dispatch model of the transmission network layer; within the dispatch cycle, the best comprehensive economic performance is taken as the optimization goal, and the transmission and distribution consistency goal is combined to set the constraints and objective functions of the distribution network layer to establish the economic dispatch model of the distribution network layer; the optimization execution results of the transmission network layer and the distribution network layer are obtained, the optimized power information of the transmission network layer and the distribution network layer is exchanged, and it is determined whether the number of iterations, iteration accuracy and consistency index meet the requirements. If the requirements are met, the optimization results of the transmission and distribution network are output. If not, the algorithm multiplier is updated, and the economic dispatch models of the transmission network layer and the distribution network layer are called for re-optimization.

[0096] In this optional embodiment, the objective function of the transmission network layer is:

[0097]

[0098] In the formula, F TN is the total objective function of the transmission network layer; is the active output of the i-th generator at time t; c0, c1, c2 are the constant term, first-order term coefficient and second-order term coefficient of the unit output cost respectively; v and w are the correction coefficients in the consistency target; N G is the total number of traditional units, T is the total scheduling cycle; The power transmitted by the transmission network to the distribution network during the transmission network layer scheduling is a control variable; It is the transmission power demand for the transmission network after the transmission network layer scheduling is completed, which is a known quantity.

[0099] In this optional embodiment, the objective function of the distribution network layer is:

[0100]

[0101] In the formula, F DN is the total objective function of the distribution network layer; are the energy storage charging and discharging power of distribution network node i at time t; c ess 、c b are the unit operating cost of energy storage and the unit power purchase cost of the upper grid respectively; v and w are the correction coefficients in the consistency target; N ess is the total number of PV and energy storage nodes; Δt is the scheduling period; It is the transmission power received by the distribution network from the transmission network during the dispatching of the distribution network layer, which is a control variable; It is the transmission power received from the transmission network after the distribution network layer scheduling is completed, which is a known quantity.

[0102] In this optional embodiment, the calculation formula of the algorithm multiplier is:

[0103]

[0104] Where γ is the algorithm multiplier update coefficient; v i 、w i are the correction coefficients in the consistency target of the i-th generation; v i+1 、w i+1 are the correction coefficients in the consistency target of the i+1th generation; It is the transmission power received from the transmission network after the distribution network layer dispatch is completed; It is the power demand for the transmission network after the distribution network layer scheduling is completed.

[0105] Figure 2 An embodiment of a transmission and distribution coordinated double-layer economic dispatching system of the present invention is shown.

[0106] In this optional embodiment, the transmission and distribution coordinated two-layer economic dispatch system includes:

[0107] The hierarchical scheduling module 201 is used to construct a hierarchical scheduling framework for the transmission and distribution network based on the operation characteristics and source-load characteristics of the transmission and distribution network, and configure the operation mode of the hierarchical scheduling of the transmission and distribution network according to the resource scheduling of the transmission and distribution network;

[0108] The coupling verification module 203 is used to set the inter-layer decoupling variables of the transmission and distribution network based on the transmission and distribution coupling characteristics of the transmission and distribution network, and to construct a consistency criterion in combination with the physical structure of the transmission and distribution network to verify the convergence of the transmission and distribution network;

[0109] The dispatch optimization module 205 is used to set the objective function and constraint conditions of the transmission and distribution network, construct an economic dispatch model of the transmission and distribution network, and optimize and update the model parameters of the economic dispatch model based on the execution results of the transmission and distribution network.

[0110] In this optional embodiment, the hierarchical scheduling module 201 includes: a transmission network layer module (not shown in the figure), a distribution network layer module (not shown in the figure) and an operation interaction module (not shown in the figure), wherein the transmission network layer module is used to obtain the electrical behavior of the transmission and distribution network during the power transmission and distribution process, and divide the power grid with a voltage level greater than a preset voltage threshold and the power supply function into the transmission network layer, and allocate the adjustable resources of the transmission network layer based on the dynamic characteristics of the power generation source and the load in the transmission network layer; the distribution network layer module is used to divide the power grid with a voltage level less than a preset voltage threshold and the power consumption function into the distribution network layer, and allocate the adjustable resources of the distribution network layer based on the dynamic characteristics of the power generation source and the load in the distribution network layer; the operation interaction module is used to set the operation mode of power self-consistency and inter-layer information interaction in the control layer based on the adjustable resources of the transmission network layer and the distribution network layer, and drive the transmission network layer and the distribution network layer to operate according to the operation mode.

[0111] In this optional embodiment, the operating mode includes an intra-layer power self-consistent mode and an inter-layer information interaction mode; the intra-layer power self-consistent mode is that the output power of the thermal power units in the transmission network layer is equal to the sum of the transmission network load power and the transmission network layer interaction power, and the sum of the distribution network layer interaction power and the photovoltaic output in the distribution network layer is equal to the sum of the distribution network load power and the energy storage system output; the inter-layer information interaction is that the transmission network layer submits the supportable active output to the distribution network layer, and the distribution network layer submits the required active output to the transmission network layer.

[0112] In this optional embodiment, the coupling verification module 203 includes: an equivalent sharing module (not shown in the figure) and a convergence verification module (not shown in the figure), wherein the equivalent sharing module is used to set the coupling interaction power between the transmission network layer and the distribution network layer as a shared variable, and when the transmission network layer performs optimization, the interaction power is set as an equivalent load to participate in the optimization, and when the distribution network layer performs optimization, the interaction power is set as an equivalent generator to participate in the optimization; the convergence verification module is used to construct a consistency criterion based on the relationship between the difference between the interaction power of the distribution network layer and the transmission network layer and a preset power threshold. When the optimization of the distribution network layer or the transmission network layer is completed, check whether the transmission power of the distribution network layer or the transmission network layer meets the consistency criterion to determine whether the optimization result converges.

[0113] In this optional embodiment, the dispatching optimization module 205 includes: a transmission network layer dispatching module (not shown in the figure), a distribution network layer dispatching module (not shown in the figure) and a model optimization module (not shown in the figure), wherein the transmission network layer dispatching module is used to set the dispatching period of the transmission and distribution network. Within the dispatching period, the lowest operating cost of the thermal power unit is taken as the optimization goal, combined with the transmission and distribution consistency goal, the constraints and objective functions of the transmission network layer are set, and the economic dispatching model of the transmission network layer is established; the distribution network layer dispatching module is used to take the best comprehensive economic performance as the optimization goal within the dispatching period, combined with the transmission and distribution consistency goal, the constraints and objective functions of the distribution network layer are set, and the economic dispatching model of the distribution network layer is established; the model optimization module is used to obtain the optimization execution results of the transmission network layer and the distribution network layer, exchange the optimized power information of the transmission network layer and the distribution network layer, and judge whether the number of iterations, iteration accuracy and consistency index meet the requirements. If the requirements are met, the optimization results of the transmission and distribution network are output; if not, the algorithm multiplier is updated, and the economic dispatching models of the transmission network layer and the distribution network layer are called for re-optimization.

[0114] The following is a detailed description of a transmission and distribution coordinated double-layer economic dispatch method and system constructed by the present invention in conjunction with specific embodiments and drawings.

[0115] like Figure 1 As shown, the transmission and distribution coordinated double-layer economic dispatch method based on the target cascade method provided in an embodiment of the present invention includes the following steps:

[0116] Step S101: Based on the operation characteristics and source-load characteristics of the transmission and distribution network, a hierarchical scheduling framework of the transmission and distribution network is constructed, and according to the resource scheduling of the transmission and distribution network, an operation mode of the hierarchical scheduling of the transmission and distribution network is configured.

[0117] Step S103: based on the transmission and distribution coupling characteristics of the transmission and distribution network, set the inter-layer decoupling variables of the transmission and distribution network, and build a consistency criterion in combination with the physical structure of the transmission and distribution network to check the convergence of the transmission and distribution network.

[0118] Step S105: set the objective function and constraint conditions of the transmission and distribution network, construct an economic dispatch model of the transmission and distribution network, and optimize and update the model parameters of the economic dispatch model in combination with the execution results of the transmission and distribution network.

[0119] Among them, the construction of the hierarchical dispatching framework of the transmission and distribution network in step S101 includes: dividing the power grid with a voltage level of 220kV and above, which plays the main power supply role, into the transmission network layer, and its adjustable resources are the output of thermal power units and the interactive power on the transmission network side; dividing the power grid with a voltage level of less than 220kV, which plays the main power consumption role (supplying power to the transmission network in some periods) into the distribution network layer, and its adjustable resources are photovoltaic output, energy storage system output and interactive power on the distribution network side; the transmission network and each distribution network operate in accordance with the mode of "power self-consistency within the layer-information interaction between layers", and have a certain degree of autonomy in dispatching, such as Figure 4 shown.

[0120] The "intra-layer power self-consistency-inter-layer information interaction" operation mode includes: "intra-layer power self-consistency" means that the output power of thermal power units in the transmission network layer is equal to the sum of the transmission network load power and the transmission network layer interaction power, and the sum of the distribution network layer interaction power and photovoltaic output in the distribution network layer is equal to the sum of the distribution network load power and the energy storage system output; "inter-layer information interaction" means that after obtaining the optimal scheduling plan within each layer, the transmission network layer submits the supported active output to the distribution network layer, and the distribution network layer submits the required active output to the transmission network layer, and the two realize information sharing to achieve optimal consistency, mainly through advanced information and communication technology to enhance the real-time monitoring and control capabilities of the power grid and realize physical interaction of information between layers.

[0121] The setting of the inter-layer decoupling variables and consistency criteria in step S103 includes: based on the basic principle of the target cascade method, the coupled interactive power between the transmission and distribution networks is used as a shared variable, and the phase angle difference at the coupling point of the transmission and distribution networks is not considered; when optimizing the transmission network layer, the interactive power is regarded as an equivalent load to participate in the optimization, and when optimizing the distribution network layer, the interactive power is regarded as an equivalent generator to participate in the optimization; after the optimization in each layer is completed, it is only necessary to consider whether the transmission power meets the following consistency criteria to determine whether it has converged, such as Figure 5 shown.

[0122] Specifically, the consistency criterion between the layers of the transmission and distribution network includes: the consistency criterion between the layers of the transmission and distribution network is based on the difference in the interactive power not exceeding a given threshold, and the calculation formula is:

[0123] In the formula, When the transmission network is dispatched at the transmission network level, the transmission network transmits power to the distribution network, which is equivalent to a virtual active load. It represents the transmission network supplying power to the distribution network, and vice versa, it represents the distribution network transmitting power to the transmission network. It is the active power purchased by the distribution network from the transmission network during the distribution network dispatching, which is equivalent to the active power of the virtual generator. It represents the power transmitted from the distribution network to the transmission network, and vice versa, the transmission network supplies power to the distribution network. ε is the convergence accuracy of the two-layer model. The same variable without an overline represents that the variable is a substitution variable.

[0124] The setting of the economic optimization model of the transmission network layer and the distribution network layer in step S105 includes: within the dispatching period, the transmission network layer takes the lowest operating cost of the thermal power units as the goal, while considering the transmission and distribution consistency goal, and the constraints include power flow constraints, node voltage constraints, thermal power unit-related constraints, and transmission network layer interactive power constraints; within the dispatching period, the distribution network layer takes the best comprehensive economy as the goal, while considering the transmission and distribution consistency goal, and the constraints include power flow constraints, node voltage constraints, energy storage system-related constraints, photovoltaic output-related constraints, and distribution network layer interactive power constraints; the transmission network layer and the distribution network layer execute the result judgment and algorithm multiplier update steps.

[0125] The transmission network layer economic dispatch model includes:

[0126] The objective function is to minimize the operating cost of thermal power units, and the calculation formula is:

[0127]

[0128] In the formula, F TN is the overall objective function of the transmission network layer, is the active output of the i-th generator at time t, c0, c1, c2 are the constant term, first-order term coefficient and second-order term coefficient of the unit output cost, v and w are the correction coefficients in the consistency target, N G is the total number of traditional units, T is the total scheduling cycle;

[0129] The power flow constraint adopts the Distflow power flow model and related constraints, and the calculation formula is:

[0130]

[0131] In the formula, are the active power and reactive power injected into the node i of the transmission network at time t, is the reactive power output of the i-th generator at time t, are the active power and reactive power of the load at the transmission network node i at time t, are the active power and reactive power of the lines between nodes i and m, and between nodes n and i at time t, respectively. TN,ni 、x TN,ni are the line resistance and reactance between the transmission network node n and node i at time t, is the square value of the node voltage of the transmission network node m at time t, is the square value of the line current between node n and node i of the transmission network at time t, a is the transmission and distribution coupling mark on the main grid side, a i =1 means that node i has a coupling relationship with the distribution network, otherwise a i = 0, perform second-order cone relaxation on the last non-convex constraint in the model to convert it into a convex constraint. The calculation formula is:

[0132]

[0133] The node voltage constraint calculation formula is:

[0134]

[0135] Where V TN,i,max 、V TN,i,min are the maximum voltage values ​​of node i in the transmission network;

[0136] The calculation formula for the relevant constraints of thermal power units is:

[0137]

[0138] In the formula, are the maximum active output and the maximum reactive output of the i-th generator, is the maximum ramp rate of the i-th generator, which is 2% / min;

[0139] The calculation formula of the interactive power at the transmission network layer is:

[0140]

[0141] In the formula, is the maximum transmission and distribution coupling power.

[0142] The distribution network layer economic dispatch model includes:

[0143] During the dispatching cycle, the distribution network layer aims to optimize its own economic operation, which mainly includes the upper power purchase cost and energy storage operation cost. The objective function calculation formula is:

[0144]

[0145] In the formula, F DN is the total objective function of the distribution network layer, are the energy storage charging and discharging power of distribution network node i at time t, c ess 、c B are the unit operating cost of energy storage and the unit power purchase cost of the upper grid, N ess is the total number of PV and energy storage nodes, Δt is the scheduling period;

[0146] The power flow constraint adopts the Distflow power flow model and related constraints, and the calculation formula is:

[0147]

[0148] In the formula, are the active power and reactive power injected into the node i of the distribution network at time t respectively; is the active and reactive power output of the i-th photovoltaic unit at time t; are the load active power and reactive power of node i in the distribution network at time t respectively; are the active power and reactive power of the lines between nodes i and m, and between nodes n and i in the distribution network at time t; r DN,ni 、x DN,ni are the line resistance and reactance between node n and node i in the distribution network at time t respectively; is the square value of the node voltage of the distribution network node m at time t, is the square value of the line current between node n and node i in the distribution network at time t; b is the transmission and distribution coupling mark on the distribution network side, b i =1 means that node i has a coupling relationship with the transmission network, otherwise b i =0;

[0149] The node voltage constraint calculation formula is:

[0150]

[0151] Where V DN,i,max 、V DN,i,min are the maximum voltage values ​​of node i in the distribution network respectively;

[0152] The calculation formula for energy storage related constraints is:

[0153]

[0154] Where P ess,i,max is the maximum output of energy storage i, is the energy stored in the energy storage at time t, η is the efficiency of the energy storage system, S ess,i,max is the rated capacity of energy storage i, are the SOC states of energy storage i at time t, initial time, and at the end of scheduling, respectively. min , SOC max are the maximum and minimum energy storage SOC respectively; the calculation formula for the interactive power on the distribution network side is:

[0155]

[0156] Furthermore, the steps of judging the economic dispatch result at the distribution network layer and updating the algorithm multiplier include:

[0157] The transmission network layer and the distribution network layer are optimized in parallel. After each layer completes the optimization, it exchanges power information to determine whether the number of iterations, iteration accuracy, and consistency indicators meet the requirements. If the requirements are met, the system outputs the optimization results. If not, the algorithm multipliers are updated and each layer is optimized again. The iterative process is as follows: Figure 6 As shown, the algorithm multiplier update calculation formula is as follows:

[0158]

[0159] Where γ is the algorithm multiplier update coefficient.

[0160] 2. Application Examples: In order to prove the creativity and technical value of the technical solution of the present invention, this section provides application examples of the technical solution of the claims on specific products or related technologies.

[0161] Example:

[0162] The present invention selects the IEEE 6-node system as the transmission network, the system reference voltage is 230kV, the reference capacity is 100MVA; the IEEE 33-node system is used as the distribution network, the system reference voltage is 12.66kV, the reference capacity is 10MVA, and 3 nodes in the transmission network and 1 node in the distribution network are combined as power coupling points to form a T6D6 example system. The network topology of the research object is as follows Figure 7-Figure 8 As shown in the figure, the total load fluctuation curve of the distribution network and the transmission network, the photovoltaic output curve of each photovoltaic storage area in the distribution network and the upper-level power purchase price are as follows Figure 9-11 The optical storage configuration parameters and algorithm initial parameters are shown in Table 1.

[0163] Table 1: Resource clustering indicators considering active scheduling capability

[0164] Parameter name Parameter Value Photovoltaic rated power 350kW Energy storage rated charge and discharge power 50kW Energy storage rated capacity 500kWh Energy storage initial SOC 0.5 Energy storage maximum / minimum SOC 0.9 / 0.1 Energy storage operation efficiency 95％ Algorithm initial penalty parameters v,w,γ 0.5 / 0.5 / 1.5 Maximum convergence accuracy of the model <![CDATA[1×10 -4 ]]>

[0165] 3. Evidence of the effects of the embodiments. The embodiments of the present invention have achieved some positive effects during the development or use process, and indeed have great advantages over the prior art. The following content is described in conjunction with the data, charts, etc. of the test process.

[0166] 1) Analysis of model convergence effect

[0167] The convergence curve of this model is as follows Fig.12 As shown in the figure, convergence is achieved at the 9th time, and the simulation time is 10.25s, which can achieve rapid convergence of transmission and distribution coordination, proving the applicability and effectiveness of the decoupling algorithm proposed in this model.

[0168] 2) Analysis of interactive power characteristics of transmission and distribution networks

[0169] The interactive power change curve of the transmission and distribution network is as follows: Fig.13 As shown in the figure, the active power of photovoltaic load in each area of ​​the distribution network during the dispatching period is as follows: Fig.14 According to the changing trend, the scheduling cycle can be divided into three periods. The operating characteristics of each period are analyzed below.

[0170] Period I (0:00-6:00): Load output is at the valley value period, photovoltaic power has no output, and energy storage releases electricity to supply power to the load. At the same time, since the electricity price is relatively low at this time, the power supply is mainly from the transmission network to the distribution network, and the transmission network provides active power to the distribution network.

[0171] Period II (7:00-18:00): Load output begins to increase, photovoltaic power begins to output and the growth rate is much higher than the load output change. Energy storage absorbs excess photovoltaic output to improve the capacity when power is insufficient and maintain the node voltage within the normal range. After absorption, the excess photovoltaic output is transmitted to the transmission network, and then the output of the transmission network units is reduced, and the operation cost of the transmission network is reduced.

[0172] Period III (19:00-24:00): The load output is at its peak, but the photovoltaic system has no output. The energy storage system releases electricity while the distribution network purchases electricity from the transmission network to cope with the power shortage. However, due to the high electricity purchase price at this time, the active power of the energy storage system has increased significantly compared to period I, playing a more significant compensation role.

[0173] By comparing the interactive power of the transmission and distribution network tie lines during separate optimization and collaborative optimization, it can be seen that during the collaborative optimization of the transmission and distribution network, the transmission network provides weaker power when the distribution network load output is low, and provides stronger power when the distribution network load is heavy. At the same time, when the photovoltaic output of the distribution network is high, the power transmitted by the distribution network to the transmission network is high, which effectively reduces the output of the units in the transmission network. In summary, the hierarchical collaborative optimization of the transmission and distribution network can effectively improve the power supplied by the transmission network to the distribution network.

[0174] 3) Economic benefit analysis

[0175] The overall operating costs of the system under the traditional independent dispatching of the transmission and distribution network and the two-layer economic dispatching of the transmission and distribution network proposed in this study are shown in Table 2. Comparing the system operating costs under the two dispatching models, it is found that the operating costs of the transmission network are reduced when the transmission and distribution network is coordinated and optimized. The main reason is that the distribution network provides electricity to the transmission network when the photovoltaic output is large, and the units of the transmission network can reduce the output, thereby reducing the operating costs of the units. For the distribution network, although the operating cost of energy storage has increased, the stored energy can support the load operation when the load demand is large, reduce the amount of electricity purchased during this period, and the overall operating cost of the distribution network has also decreased. In summary, compared with the traditional independent dispatching of the transmission and distribution network, the two-layer economic dispatching method of the transmission and distribution network based on the target cascade method can effectively reduce the system operating costs.

[0176] Table 2: Overall operating cost of the transmission and distribution system under different dispatch strategies

[0177]

[0178] In one embodiment, a computer device is provided. The computer device may be a server, and its internal structure diagram may be as follows: Figure 3 As shown. The computer device includes a processor, a memory and a network interface connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store static information and dynamic information data. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, the steps in the above method embodiment are implemented.

[0179] Those skilled in the art will understand that Figure 3 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present invention, and does not constitute a limitation on the computer device to which the solution of the present invention is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0180] In addition, the present invention also provides a computer device, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps in the above method embodiment when executing the computer program.

[0181] In addition, the present invention further provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps in the above method embodiment are implemented.

[0182] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided by the present invention can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory or optical memory, etc. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0183] The present invention is not limited to the structures which have been described above and shown in the drawings, and various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. A transmission and distribution coordinated double-layer economic dispatch method, characterized in that: include: Based on the operation characteristics and source-load characteristics of the transmission and distribution network, a hierarchical dispatching framework for the transmission and distribution network is constructed, and the operation mode of the hierarchical dispatching of the transmission and distribution network is configured according to the resource dispatching of the transmission and distribution network; Based on the transmission and distribution coupling characteristics of the transmission and distribution network, the inter-layer decoupling variables of the transmission and distribution network are set, and combined with the physical structure of the transmission and distribution network, a consistency criterion is constructed to verify the convergence of the transmission and distribution network; The objective function and constraints of the transmission and distribution network are set, the economic dispatch model of the transmission and distribution network is constructed, and the model parameters of the economic dispatch model are optimized and updated based on the execution results of the transmission and distribution network.

2. The transmission and distribution coordinated double-layer economic dispatch method according to claim 1 is characterized in that: The hierarchical dispatching framework of the transmission and distribution network is constructed based on the operation characteristics and source-load characteristics of the transmission and distribution network, and the operation mode of the hierarchical dispatching of the transmission and distribution network is configured according to the resource dispatching of the transmission and distribution network, including: Obtain the electrical behavior of the transmission and distribution network during the power transmission and distribution process, classify the power grids with voltage levels greater than a preset voltage threshold and that are responsible for power supply into the transmission network layer, and allocate the adjustable resources of the transmission network layer based on the dynamic characteristics of the power generation sources and loads in the transmission network layer; Classify the power grid whose voltage level is less than the preset voltage threshold and bears the power consumption function into the distribution network layer, and allocate the adjustable resources of the distribution network layer based on the dynamic characteristics of the power generation source and the load in the distribution network layer; Based on the adjustable resources of the transmission network layer and the distribution network layer, the operation mode of power self-consistency and information interaction between layers in the control layer is set, and the transmission network layer and the distribution network layer are driven to operate according to the operation mode.

3. The transmission and distribution coordinated double-layer economic dispatch method according to claim 2 is characterized in that: The operation modes include an intra-layer power self-consistent mode and an inter-layer information interaction mode; The intra-layer power self-consistent mode is that the output power of the thermal power units in the transmission network layer is equal to the sum of the transmission network load power and the transmission network layer interaction power, and the sum of the distribution network layer interaction power and the photovoltaic output in the distribution network layer is equal to the sum of the distribution network load power and the energy storage system output; The inter-layer information interaction is that the transmission network layer submits the supported active power output to the distribution network layer, and the distribution network layer submits the required active power output to the transmission network layer.

4. The transmission and distribution coordinated double-layer economic dispatch method according to claim 1 is characterized in that: The above-mentioned method of setting the inter-layer decoupling variables of the transmission and distribution network based on the transmission and distribution coupling characteristics of the transmission and distribution network, and constructing the consistency criterion in combination with the physical structure of the transmission and distribution network to check the convergence of the transmission and distribution network includes: The coupled interactive power between the transmission network layer and the distribution network layer is set as a shared variable. When the transmission network layer performs optimization, the interactive power is set as an equivalent load to participate in the optimization. When the distribution network layer performs optimization, the interactive power is set as an equivalent generator to participate in the optimization. Based on the relationship between the difference in interaction power between the distribution network layer and the transmission network layer and the preset power threshold, a consistency criterion is constructed. When the optimization of the distribution network layer or the transmission network layer is completed, it is checked whether the transmission power of the distribution network layer or the transmission network layer meets the consistency criterion and whether the optimization result converges.

5. The transmission and distribution coordinated double-layer economic dispatch method according to claim 4 is characterized in that: The calculation formula of the consistency criterion is: In the formula, The transmission network delivers power to the distribution network during the transmission network layer dispatching; is the active power purchased by the distribution network from the transmission network during the distribution network layer dispatch; ε is the convergence accuracy of the two-layer model.

6. The transmission and distribution coordinated double-layer economic dispatch method according to claim 1 is characterized in that: The objective function and constraint conditions of the transmission and distribution network are set, the economic dispatch model of the transmission and distribution network is constructed, and the model parameters of the economic dispatch model are optimized and updated in combination with the execution results of the transmission and distribution network, including: Set the dispatching cycle of the transmission and distribution network. Within the dispatching cycle, take the lowest operating cost of thermal power units as the optimization goal, combine the transmission and distribution consistency goal, set the constraints and objective function of the transmission network layer, and establish the economic dispatching model of the transmission network layer. In the dispatching cycle, taking the comprehensive economic optimization as the optimization goal, combined with the transmission and distribution consistency goal, the constraints and objective functions of the distribution network layer are set, and the economic dispatching model of the distribution network layer is established; Obtain the optimization execution results of the transmission network layer and the distribution network layer, exchange the optimized power information of the transmission network layer and the distribution network layer, and determine whether the number of iterations, iteration accuracy and consistency indicators meet the requirements. If they meet the requirements, output the optimization results of the transmission and distribution network. If they do not meet the requirements, update the algorithm multiplier and call the economic dispatch model of the transmission network layer and the distribution network layer for re-optimization.

7. The transmission and distribution coordinated double-layer economic dispatch method according to claim 6 is characterized in that: The objective function of the transmission network layer is: In the formula, F TN is the total objective function of the transmission network layer; is the active output of the i-th generator at time t; c0, c1, c2 are the constant term, first-order term coefficient and second-order term coefficient of the unit output cost respectively; v and w are the correction coefficients in the consistency target; N G is the total number of traditional units, T is the total scheduling cycle; The transmission network delivers power to the distribution network during the transmission network layer dispatching; It is the transmission power demand for the transmission network after the transmission network layer scheduling is completed.

8. The transmission and distribution coordinated double-layer economic dispatch method according to claim 6 is characterized in that: The objective function of the distribution network layer is: In the formula, F DN is the total objective function of the distribution network layer; are the energy storage charging and discharging power of distribution network node i at time t; c ess 、c b They are the unit operating cost of energy storage and the unit electricity purchase cost of the upper-level power grid; v, w are the correction coefficients in the consistency target; N ess is the total number of PV and energy storage nodes; Δt is the scheduling period; It is the transmission power received by the distribution network from the transmission network during the dispatching of the distribution network layer; It is the transmission power received from the transmission network after the distribution network layer scheduling is completed.

9. The transmission and distribution coordinated double-layer economic dispatch method according to claim 6 is characterized in that: The calculation formula of the algorithm multiplier is: Where γ is the algorithm multiplier update coefficient; v i 、w i are the correction coefficients in the consistency target of the i-th generation; v i+1 、w i+1 are the correction coefficients in the consistency target of the i+1th generation; It is the transmission power received from the transmission network after the distribution network layer dispatch is completed; It is the power demand for the transmission network after the distribution network layer scheduling is completed.

10. A transmission and distribution coordinated double-layer economic dispatch system, characterized in that: include: The hierarchical dispatching module is used to construct a hierarchical dispatching framework for the transmission and distribution network based on the operation characteristics and source-load characteristics of the transmission and distribution network, and configure the operation mode of the hierarchical dispatching of the transmission and distribution network according to the resource dispatching of the transmission and distribution network; The coupling verification module is used to set the inter-layer decoupling variables of the transmission and distribution network based on the transmission and distribution coupling characteristics of the transmission and distribution network, and to build a consistency criterion in combination with the physical structure of the transmission and distribution network to verify the convergence of the transmission and distribution network; The dispatch optimization module is used to set the objective function and constraints of the transmission and distribution network, build the economic dispatch model of the transmission and distribution network, and optimize and update the model parameters of the economic dispatch model based on the execution results of the transmission and distribution network.

11. The transmission and distribution coordinated double-layer economic dispatching system according to claim 10 is characterized in that: The hierarchical scheduling module includes: a transmission network layer module, a distribution network layer module and an operation interaction module, wherein: The transmission network layer module is used to obtain the electrical behavior of the transmission and distribution network during the power transmission and distribution process, classify the power grids with voltage levels greater than a preset voltage threshold and that are responsible for power supply into the transmission network layer, and allocate the adjustable resources of the transmission network layer based on the dynamic characteristics of the power generation sources and loads in the transmission network layer; The distribution network layer module is used to classify the power grids with voltage levels less than a preset voltage threshold and that consume electricity into the distribution network layer, and allocate the adjustable resources of the distribution network layer based on the dynamic characteristics of the power generation sources and loads in the distribution network layer; The operation interaction module is used to set the operation mode of power self-consistency and inter-layer information interaction within the control layer based on the adjustable resources of the transmission network layer and the distribution network layer, and drive the transmission network layer and the distribution network layer to operate according to the operation mode.

12. The transmission and distribution coordinated double-layer economic dispatching system according to claim 11 is characterized in that: The operation modes include an intra-layer power self-consistent mode and an inter-layer information interaction mode; The intra-layer power self-consistent mode is that the output power of the thermal power units in the transmission network layer is equal to the sum of the transmission network load power and the transmission network layer interaction power, and the sum of the distribution network layer interaction power and the photovoltaic output in the distribution network layer is equal to the sum of the distribution network load power and the energy storage system output; The inter-layer information interaction is that the transmission network layer submits the supported active power output to the distribution network layer, and the distribution network layer submits the required active power output to the transmission network layer.

13. The transmission and distribution coordinated double-layer economic dispatching system according to claim 10 is characterized in that: The coupling verification module includes: an equivalent sharing module and a convergence verification module, wherein The equivalent sharing module is used to set the coupled interactive power between the transmission network layer and the distribution network layer as a shared variable. When the transmission network layer performs optimization, the interactive power is set as an equivalent load to participate in the optimization. When the distribution network layer performs optimization, the interactive power is set as an equivalent generator to participate in the optimization. The convergence verification module is used to construct a consistency criterion based on the relationship between the difference in interaction power between the distribution network layer and the transmission network layer and a preset power threshold. When the optimization of the distribution network layer or the transmission network layer is completed, it is used to check whether the transmission power of the distribution network layer or the transmission network layer meets the consistency criterion and determine whether the optimization result converges.

14. The transmission and distribution coordinated double-layer economic dispatching system according to claim 10 is characterized in that: The dispatch optimization module includes: a transmission network dispatch module, a distribution network dispatch module and a model optimization module, wherein: The transmission network dispatching module is used to set the dispatching period of the transmission and distribution network. Within the dispatching period, the lowest operating cost of the thermal power units is taken as the optimization goal. In combination with the transmission and distribution consistency goal, the constraints and objective functions of the transmission network layer are set, and the economic dispatching model of the transmission network layer is established. The distribution network layer scheduling module is used to set the constraints and objective functions of the distribution network layer and establish the economic scheduling model of the distribution network layer within the scheduling period, taking the comprehensive economic optimization as the optimization goal, combining the transmission and distribution consistency goal; The model optimization module is used to obtain the optimization execution results of the transmission network layer and the distribution network layer, exchange the power information of the optimized transmission network layer and the distribution network layer, and determine whether the number of iterations, iteration accuracy and consistency indicators meet the requirements. If the requirements are met, the optimization results of the transmission and distribution network are output; if not, the algorithm multiplier is updated, and the economic dispatch model of the transmission network layer and the distribution network layer is called for re-optimization.

15. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 9 are implemented.

16. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 9 are implemented.

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