Transmission and distribution coordinated asynchronous power grid dispatching method, system, equipment and medium

Abstract

The invention discloses a transmission and distribution collaborative asynchronous power grid dispatching method, system and device and a medium, and relates to the technical field of power grid management and control, in the current iteration process, when first update data from at least S power distribution systems are received, second update data are obtained through calculation by adopting a forward-backward operator splitting algorithm; according to the second updating data, calculating to obtain a power grid power flow value, and judging whether the power grid power flow value meets an iteration ending condition or not; if not, sending the second update data to the power distribution system, so that the power distribution system sends first update data for next iteration; if yes, scheduling data are obtained according to the power grid power flow value, and power grid scheduling is carried out. By adopting the embodiment of the invention, the problems of the power transmission system and the power distribution system are respectively processed by utilizing the asynchronous forward and backward operator splitting algorithm, and the overall calculation efficiency and the operation stability of the transmission and distribution integrated system can be remarkably improved.

Description

Technical Field

[0001] The present invention relates to the field of power grid control technology, and in particular to a transmission and distribution coordinated asynchronous power grid dispatching method, system, equipment and medium. Background Art

[0002] In traditional power systems, transmission and distribution networks are often dispatched and controlled independently. Although this hierarchical and graded management system was able to meet the basic needs of the power system in the past, with the development of the power market and the construction of the energy Internet, the coupling relationship between the transmission and distribution networks has become increasingly complex.

[0003] The traditional method of synchronously calculating power grid trends is based on the traditional power system to independently calculate the transmission network and distribution network. However, when it is applied to the integrated transmission and distribution system, there are problems of low calculation efficiency and poor real-time performance, resulting in the calculation efficiency and accuracy of the management systems of the transmission and distribution networks being unable to meet engineering requirements. Summary of the invention

[0004] The technical problem to be solved by the present invention is how to improve the real-time performance of power grid dispatching, and to provide a transmission and distribution coordinated asynchronous power grid dispatching method, system, equipment and medium, which can significantly improve the computational efficiency and operational stability of the overall dispatching of the integrated transmission and distribution system.

[0005] In order to solve the above technical problems, an embodiment of the present invention provides a transmission and distribution coordinated asynchronous power grid dispatching method, comprising:

[0006] In the current iteration process, when first update data from at least S distribution systems is received, a forward-backward operator splitting algorithm is used to calculate and obtain second update data; both the first update data and the second update data include boundary node data of the transmission system and the distribution system;

[0007] Calculating a power grid flow value according to the second updated data, and determining whether the power grid flow value satisfies an iteration end condition;

[0008] If not, sending the second update data to the power distribution system, so that the power distribution system sends out the first update data for the next iteration according to the second update data;

[0009] If so, dispatching data is obtained according to the power grid flow value, and power grid dispatching is performed according to the dispatching data.

[0010] As an improvement of the above solution, in the current iteration process, when first update data from at least S power distribution systems is received, a forward-backward operator splitting algorithm is used to calculate and obtain second update data, including:

[0011] In the current iteration, when first update data from at least S power distribution systems is received, the second update data in the previous iteration is obtained;

[0012] According to the first update data and the second update data in the previous iteration, the first update data is updated using a forward-backward operator splitting algorithm to obtain the second update data of the current iteration.

[0013] As an improvement of the above solution, if the current iteration is the first iteration, in the current iteration, when first update data from at least S power distribution systems is received, obtaining the second update data in the previous iteration includes:

[0014] Get initial boundary node data;

[0015] In the current iteration, when the first update data from at least S power distribution systems is received, the initial boundary node data is used as the second update data in the previous iteration.

[0016] As an improvement of the above solution, the first update data is updated according to the first update data and the second update data in the previous iteration by using a forward-backward operator splitting algorithm to obtain the second update data of the current iteration, including:

[0017] Calculating a current global vector of a boundary node between the power transmission system and the power distribution system according to the first updated data and the second updated data in the previous iteration;

[0018] Calculating a power flow value of the power transmission system according to the current global vector;

[0019] According to the power flow value, the current global vector is updated by using a forward-backward operator splitting algorithm to obtain an updated global variable;

[0020] According to the updated global variable, the second updated data of the current iteration is obtained.

[0021] As an improvement of the above solution, in the current iteration process, when first update data from at least S distribution systems is received, before the forward-backward operator splitting algorithm is used to calculate the second update data, the power grid scheduling method further includes:

[0022] Acquire the hysteresis step number of each power distribution system; the hysteresis step number of each power distribution system is updated after each iteration;

[0023] The power distribution system with the hysteresis step number not less than τ is used as a hysteresis power distribution system;

[0024] Then, the at least S power distribution systems include a lagging power distribution system.

[0025] As an improvement of the above solution, a method for updating the hysteresis step number of each power distribution system includes:

[0026] If the first update data received during the current iteration is from a power distribution system, resetting the hysteresis step number of the power distribution system after the current iteration;

[0027] If the first update data received in the current iteration does not come from a power distribution system, the hysteresis step number of the power distribution system is incremented after the current iteration.

[0028] As an improvement of the above solution, the calculating of the power grid flow value according to the second updated data and judging whether the power grid flow value satisfies the iteration end condition include:

[0029] A power grid flow value is calculated according to the second updated data; the power grid flow value includes a first power flow value of the power transmission system and a second power flow value of each of the power distribution systems;

[0030] Determining the convergence of the power grid flow value;

[0031] If the power grid flow value does not converge, it is considered that the power grid flow value does not meet the iteration end condition;

[0032] If the power grid flow value converges, it is considered that the power grid flow value meets the iteration end condition.

[0033] As an improvement of the above solution, the step of calculating the power grid flow value according to the second updated data includes:

[0034] Acquire the voltage amplitude, voltage phase angle, active power and reactive power of the boundary node between the power transmission system and the power distribution system according to the second update data;

[0035] Calculating a first power flow value of the power transmission system according to the voltage amplitude and the voltage phase angle;

[0036] Calculating a second power flow value of each of the power distribution systems according to the active power and the reactive power;

[0037] A power grid power flow value is obtained according to the first power flow value and the second power flow value.

[0038] As an improvement of the above solution, the step of determining the convergence of the power grid flow value includes:

[0039] According to the power grid flow value, a spectrum radius index is calculated;

[0040] When the spectrum radius index is less than 1, it is determined that the power grid power flow value is converged; otherwise, it is determined that the power grid power flow value is not converged.

[0041] The embodiment of the present invention further provides an asynchronous power grid dispatching system for transmission and distribution coordination, comprising:

[0042] A data updating module, configured to, in a current iteration process, when receiving first update data from at least S distribution systems, calculate second update data using a forward-backward operator splitting algorithm; the first update data and the second update data both include boundary node data of the transmission system and the distribution system;

[0043] An iteration end judgment module, used to calculate a power grid flow value according to the second updated data, and judge whether the power grid flow value meets the iteration end condition;

[0044] a data sending module, configured to send the second update data to the power distribution system if no, so that the power distribution system sends the first update data for the next iteration according to the second update data;

[0045] The power grid dispatching module is used to obtain dispatching data according to the power grid flow value, and perform power grid dispatching according to the dispatching data.

[0046] As an improvement of the above solution, the data updating module includes:

[0047] a previous iteration data acquisition unit, configured to acquire the second updated data in the previous iteration when receiving the first updated data from at least S power distribution systems;

[0048] The current iteration data updating unit is used to update the first update data according to the first update data and the second update data in the previous iteration by adopting a forward-backward operator splitting algorithm to obtain the second update data of the current iteration.

[0049] As an improvement of the above solution, if the current iteration is the first iteration, the previous iteration data acquisition unit is specifically used to:

[0050] Get initial boundary node data;

[0051] When the first update data from at least S power distribution systems is received, the initial boundary node data is used as the second update data in the previous iteration.

[0052] As an improvement of the above solution, the current iteration data updating unit is specifically used for:

[0053] Calculating a current global vector of a boundary node between the power transmission system and the power distribution system based on the first updated data and the second updated data in the previous iteration;

[0054] Calculating a power flow value of the power transmission system according to the current global vector;

[0055] According to the power flow value, the current global vector is updated by using a forward-backward operator splitting algorithm to obtain an updated global variable;

[0056] According to the updated global variable, the second updated data of the current iteration is obtained.

[0057] As an improvement of the above solution, the power grid dispatching system further includes:

[0058] A hysteresis step number acquisition module, used to acquire the hysteresis step number of each of the power distribution systems; the hysteresis step number of each of the power distribution systems is updated after each iteration;

[0059] A power distribution system screening module, used for selecting the power distribution system with the hysteresis step number not less than τ as a lagging power distribution system;

[0060] Then, the at least S power distribution systems include a lagging power distribution system.

[0061] As an improvement of the above solution, a method for updating the hysteresis step number of each power distribution system includes:

[0062] If the first update data received during the current iteration is from a power distribution system, resetting the hysteresis step number of the power distribution system after the current iteration;

[0063] If the first update data received in the current iteration does not come from a power distribution system, the hysteresis step number of the power distribution system is incremented after the current iteration.

[0064] As an improvement of the above solution, the iteration end judgment module includes:

[0065] A power flow value calculation unit, configured to calculate a power grid power flow value according to the second updated data; the power grid power flow value includes a first power flow value of the power transmission system and a second power flow value of each of the power distribution systems;

[0066] A convergence determination unit, used to determine the convergence of the power grid power flow value;

[0067] A first convergence condition determination unit, configured to determine that the power grid flow value does not meet an iteration end condition if the power grid flow value does not converge;

[0068] The second convergence condition determination unit is configured to determine that, if the power grid power flow value converges, the power grid power flow value satisfies an iteration end condition.

[0069] As an improvement of the above solution, the power flow value calculation unit is specifically used for:

[0070] Acquire the voltage amplitude, voltage phase angle, active power and reactive power of the boundary node between the power transmission system and the power distribution system according to the second update data;

[0071] Calculating a first power flow value of the power transmission system according to the voltage amplitude and the voltage phase angle;

[0072] Calculating a second power flow value of each of the power distribution systems according to the active power and the reactive power;

[0073] A power grid power flow value is obtained according to the first power flow value and the second power flow value.

[0074] As an improvement of the above solution, the convergence determination unit is specifically used to:

[0075] According to the power grid flow value, a spectrum radius index is calculated;

[0076] When the spectrum radius index is less than 1, it is determined that the power grid power flow value is converged; otherwise, it is determined that the power grid power flow value is not converged.

[0077] An embodiment of the present invention also provides an asynchronous power grid dispatching device with coordinated transmission and distribution, comprising a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein when the processor executes the computer program, it implements an asynchronous power grid dispatching method with coordinated transmission and distribution as described in any one of the above.

[0078] Compared with the prior art, the present invention discloses a method, system, device and medium based on power grid dispatching. In the current iteration process, when receiving the first update data from at least S distribution systems, the forward-backward operator splitting algorithm is used to calculate the second update data; the first update data and the second update data both include the boundary node data of the transmission system and the distribution system; according to the second update data, the power grid flow value is calculated to determine whether the power grid flow value meets the iteration end condition; if not, the second update data is sent to the distribution system, so that the distribution system sends the first update data for the next iteration according to the second update data; if so, the dispatching data is obtained according to the power grid flow value, and the power grid dispatching is performed according to the dispatching data. The use of the embodiments of the present invention can significantly improve the computational efficiency and operational stability of the overall dispatching of the integrated transmission and distribution system. BRIEF DESCRIPTION OF THE DRAWINGS

[0079] Figure 1 It is a schematic diagram of the steps of a transmission and distribution coordinated asynchronous power grid dispatching method provided by an embodiment of the present invention;

[0080] Figure 2 is a schematic diagram of a maximum hysteresis constraint provided by an embodiment of the present invention;

[0081] Figure 3 It is a timing diagram of information interaction between a power transmission system and a power distribution system provided by an embodiment of the present invention;

[0082] Figure 4 It is a structural diagram of an asynchronous power grid dispatching system for transmission and distribution coordination provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0083] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0084] In the description of the specification and claims, it is to be understood that the terms first, second, etc. in the specification and claims are only used for the purpose of describing the same technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated, nor necessarily describing the order or time sequence. The terms are interchangeable where appropriate. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0085] In traditional power systems, transmission networks and distribution networks are often dispatched and controlled independently. Although this hierarchical and graded management system was able to meet the basic needs of the power system in the past, with the development of the power market and the construction of the energy Internet, this model has gradually shown its limitations. In the integrated transmission and distribution system, if the traditional grid dispatching method is still used, the computing efficiency and computing power of the management system of the transmission and distribution networks will not meet the engineering requirements.

[0086] It should be noted that, in the embodiments of the present invention, it is more applicable to an integrated transmission and distribution power grid, which includes a transmission system and a distribution system. The transmission system and the distribution system exchange information through boundary nodes to coordinate and correct their respective parameters.

[0087] It should also be noted that due to the structure of power supply and power consumption, one transmission system in the power grid generally corresponds to several distribution systems.

[0088] In the traditional power grid dispatching method, the transmission system will update the data of the boundary nodes after receiving the data from all distribution systems, and then send the updated data to the distribution system, and continue to iterate until convergence.

[0089] However, the traditional power grid dispatching method needs to wait for all distribution systems to complete data transmission. If there is a communication delay problem in the distribution system, each iteration will take a long time, resulting in low computing efficiency.

[0090] Based on the above considerations, an embodiment of the present invention provides a power grid dispatching method applied to a power transmission system. Figure 1 In this embodiment, the power grid dispatching method is specifically performed through steps S1 to S4:

[0091] S1. In the current iteration process, when first update data is received from at least S distribution systems, the forward-backward operator splitting algorithm is used to calculate the second update data; the first update data and the second update data both include the boundary node data of the transmission system and the distribution system.

[0092] It should be noted that in the embodiment of the present invention, S is the minimum synchronization number. The transmission system does not need to wait for the data of all distribution systems to be transmitted before performing calculations as in the traditional scheduling method. When the transmission network receives a sufficient amount of first update data, it can start data updating and iterative calculations. This can alleviate the lag problem caused by communication delays or excessive computing load in some distribution systems and improve the overall computing efficiency of the system.

[0093] S2. Calculate a power grid flow value according to the second updated data, and determine whether the power grid flow value meets an iteration end condition.

[0094] It should be noted that the boundary node is the hub between the transmission system and the distribution system. The transmission system and the distribution system can further solve the transmission problem and the distribution problem by exchanging the data of the boundary nodes, and gradually iterate to generate the optimal scheduling data solution. During the iteration process, the distribution system sends the first updated data to the transmission system. The transmission system updates the data of the boundary nodes in the first updated data based on the first updated data and the solution of the transmission part of the problem, and then sends the obtained second updated data to the distribution system. The distribution system updates the data of the boundary nodes in the second updated data based on the second updated data and the solution of the distribution part of the problem, and obtains the first updated data. This cycle can be repeated to achieve the final generated scheduling data tending to the optimal solution of power grid scheduling, ensuring the correctness and reliability of the scheduling data.

[0095] S3. If not, sending the second update data to the power distribution system, so that the power distribution system issues the first update data for the next iteration according to the second update data.

[0096] S4. If yes, obtain dispatching data according to the power grid flow value, and perform power grid dispatching according to the dispatching data.

[0097] It should also be noted that the embodiment of the present invention adopts an asynchronous forward and backward operator splitting power grid dispatching method. Through the asynchronous computing mode, the frequency of data exchange between computing nodes is reduced, and the computing efficiency and real-time performance are improved. Specifically, the forward operator is responsible for processing the computing tasks of the transmission system, and the backward operator processes the computing tasks of the distribution system. The two coordinate through the information exchange of the boundary nodes, and gradually correct their respective calculation results until the convergence conditions are reached. This method not only improves the computing efficiency, but also can solve the problem of poor convergence in traditional methods to a certain extent.

[0098] In an embodiment of the present invention, by decomposing the computing tasks of the transmission system and the distribution system, and using the asynchronous forward-backward operator splitting algorithm to handle the problems of the transmission system and the distribution system respectively, the overall computing efficiency and operating stability of the integrated transmission and distribution system can be significantly improved.

[0099] As a preferred implementation, step S1, in the current iteration process, when first update data from at least S power distribution systems is received, a forward-backward operator splitting algorithm is used to calculate and obtain second update data, including:

[0100] In the current iteration, when first update data from at least S power distribution systems is received, the second update data in the previous iteration is obtained;

[0101] According to the first update data and the second update data in the previous iteration, the first update data is updated using a forward-backward operator splitting algorithm to obtain the second update data of the current iteration.

[0102] It should be noted that the power flow calculation of the transmission system can be expressed as T φ ([V B θ B ])=[P′ B ; Q′ B ]; The power flow value calculation of the distribution system can be expressed as D φ ([P B ;Q B ])=[V′ B θ′ B ]; where P′ B is the active power of the boundary node in the first update data; Q′B is the reactive power of the boundary node in the first update data; V′ B is the voltage amplitude of the boundary node in the second update data; θ′ B is the voltage phase angle of the boundary node in the second updated data. Therefore, the final active power of the boundary node is Reactive power Voltage Amplitude and voltage phase angle Must satisfy both and

[0103] It should also be noted that the first updated data includes the active power and reactive power of the boundary nodes, but in order to perform iterative calculations for power grid scheduling, it is also necessary to obtain the voltage amplitude and voltage phase angle of the boundary nodes. In some embodiments of the present invention, this is obtained by obtaining the boundary node data of the previous iteration; in other embodiments, the voltage amplitude and voltage phase angle of the boundary node may be vector-merged with the active power and reactive power obtained by calculation to obtain a vector including active power, reactive power, voltage amplitude and voltage phase angle as the first updated data.

[0104] Further, preferably, if the current iteration is the first iteration, in the current iteration, when first update data from at least S power distribution systems is received, obtaining the second update data in the previous iteration includes:

[0105] Get initial boundary node data;

[0106] In the current iteration, when the first update data from at least S power distribution systems is received, the initial boundary node data is used as the second update data in the previous iteration.

[0107] It should be noted that, in the embodiment of the present invention, before the power grid dispatch calculation, the power grid needs to be initialized in advance. Specifically, the boundary node data, Lagrange multipliers, control variables and state variables of the transmission system and the distribution system are initialized respectively. Initializing the boundary node data provides an initial state for iterative calculation.

[0108] Exemplarily, the voltage amplitude V of the boundary node in the initialization grid is B is 1.0pu, initialization voltage phase angle θ B =0 degrees, and then set the active power and reactive power injected into the boundary nodes according to the load distribution and generation plan of the system. Set the Lagrange multiplier λ (0) = 0. Initialize the control variables based on historical operation data, and initialize the state variables according to the preliminary power flow calculation.

[0109] The initial boundary node data provides an initial state for subsequent iterative calculations, allowing the system to gradually approach the true optimal solution in the next iteration. Lagrange multipliers are bilateral constraints used to coordinate boundary variables between the transmission system and the distribution system. By initializing Lagrange multipliers, the convergence of the initial iteration can be accelerated. The control variables include generator output, transformer ratio, and set values ​​of reactive compensation devices; the state variables include the voltage amplitude and phase angle of each node, and line flow.

[0110] In some embodiments, as a preferred implementation, the updating of the first update data using a forward-backward operator splitting algorithm according to the first update data and the second update data in the previous iteration to obtain the second update data of the current iteration includes:

[0111] Calculating a current global vector of a boundary node between the power transmission system and the power distribution system according to the first updated data and the second updated data in the previous iteration;

[0112] Calculating a power flow value of the power transmission system according to the current global vector;

[0113] According to the power flow value, the current global vector is updated by using a forward-backward operator splitting algorithm to obtain an updated global variable;

[0114] According to the updated global variable, the second updated data of the current iteration is obtained.

[0115] It should be noted that the current global variable can be the vector data of the boundary nodes with a consistent relationship between the power transmission system and all the power distribution systems, or the vector data of the boundary nodes between the power transmission system and a specific power distribution system. However, it is necessary to satisfy that when the generated second update data is sent to the power distribution system, at least the specific power distribution system can perform iterative calculation.

[0116] For example, by x t+1 =(1-η)x t +ηT(x transmit ), updating the first update data to obtain second update data;

[0117] Among them, x t+1 is the second update data; η∈[0,1]; x t is the first updated data, x transmit is the current global variable, T(·) is the power flow calculation function; a t,j is the additional error of the j-th distribution system; x t,jis the first updated data of the jth power distribution system, x t-l,j It is the first updated data when removing the influence of the lag step number l for the j-th power distribution system.

[0118] As a preferred implementation, before step S1, the power grid dispatching method further includes:

[0119] Acquire the hysteresis step number of each power distribution system; the hysteresis step number of each power distribution system is updated after each iteration;

[0120] The power distribution system with the hysteresis step number not less than τ is used as a hysteresis power distribution system;

[0121] Then, the at least S power distribution systems include a lagging power distribution system.

[0122] It should be noted that the hysteresis step number represents the difference between the data update arrival time of the distribution system and the data update time of the transmission system. By setting the maximum hysteresis parameter τ, it can be ensured that each distribution system updates data at least once within τ iterations.

[0123] More preferably, in some embodiments, a global clock of the power transmission system and a local clock of the power distribution system are preset, and each time an iteration is performed, the global clock and the local clock are always incremented simultaneously.

[0124] Further, preferably, the method for updating the hysteresis step number of each of the power distribution systems comprises:

[0125] If the first update data received during the current iteration is from a power distribution system, resetting the hysteresis step number of the power distribution system after the current iteration;

[0126] If the first update data received in the current iteration does not come from a power distribution system, the hysteresis step number of the power distribution system is incremented after the current iteration.

[0127] See also Figure 2In this embodiment, a total of 5 distribution systems are shown, τ=8, and the transmission network time is a preset clock signal, which acts on the transmission system and all distribution systems at the same time. For distribution system 4, at transmission network time 1-2, the transmission system can receive the first update data from all distribution systems, so the transmission system performs a data update and iteration at transmission network time 1 and transmission network time 2 respectively, and resets the hysteresis steps of all distribution systems. At transmission network moments 3-5, the transmission system can receive the first update data of all distribution systems except the distribution system 4, and the number thereof is greater than the preset S. Therefore, the transmission system performs a data update and iteration at transmission network moments 3, 4 and 5 respectively, and increases the lag step number of the distribution system 4 by 1 at each distribution network moment. The lag step number of the unupdated distribution system 4 relative to the transmission system at transmission network moment 5 is 3; at transmission network moments 6-9, the transmission system can only receive the first update data from the distribution system 1 and the distribution system 5, and the number thereof meets the preset S. Therefore, the transmission system performs a data update and iteration at transmission network moments 6, 7, 8 and 9 respectively. The lag step number of the unupdated distribution system 4 relative to the transmission system at transmission network moment 9 is 7, and the lag step numbers of the unupdated distribution system 2 and the distribution system 3 relative to the transmission system at transmission network moment 9 are both 4. Therefore, after the transmission network time 9, it is necessary to wait for the first update data of the distribution system 4 to arrive before the data update and iteration of the transmission system can be performed, otherwise the lag step number for the distribution system 4 will be equal to τ.

[0128] See also Figure 3 , when time k is 0, distribution systems 1-5 begin to update their data, distribution systems 2 and 3 complete their data update and data transmission first, and when the transmission system receives the first updated data from distribution systems 2 and 3, the first iteration begins; then the transmission network receives the first updated data from distribution systems 4 and 5, and the second iteration begins; in the third iteration, although the transmission system has received the first updated data from distribution systems 2 and 3, distribution system 1 has not yet completed data transmission, and its lag step number has reached 2, so it is necessary to wait for the data transmission of distribution system 1 to be completed. When the transmission system receives the first updated data from distribution system 1, the third iteration begins.

[0129] As a preferred implementation manner, step S2, calculating a power grid flow value according to the second updated data, and judging whether the power grid flow value satisfies an iteration end condition, includes:

[0130] A power grid flow value is calculated according to the second updated data; the power grid flow value includes a first power flow value of the power transmission system and a second power flow value of each of the power distribution systems;

[0131] Determining the convergence of the power grid flow value;

[0132] If the power grid flow value does not converge, it is considered that the power grid flow value does not meet the iteration end condition;

[0133] If the power grid flow value converges, it is considered that the power grid flow value meets the iteration end condition.

[0134] It should be noted that the power grid flow value is the basis of power system operation and planning. It can depict the operating status of the power system and provide an important reference for system operation and planning. In order to better carry out the dispatching planning of the power grid, when calculating the power grid flow value, the optimization objectives of the transmission system and the distribution system are taken into account. Specifically, the weight factor ω is introduced to generate a comprehensive objective according to the optimization objectives of the transmission system and the distribution system. in, For the optimization goal of the transmission system, is the minimum value of the central objective function of the transmission system, is the maximum value of the central objective function of the transmission system; For the optimization goal of the distribution system, is the minimum value of the central objective function of the distribution system, It is the maximum value of the central objective function of the distribution system.

[0135] It should be noted that iteration is implemented in the interaction between the transmission system and the distribution system. During the iteration process, the transmission system first sends the initial Lagrange multiplier and initial boundary node data to the distribution system, and then the distribution system generates the first update data based on the received data, and sends the first update data to the transmission system. The transmission system then determines the convergence of the power grid flow based on the first update data. If it does not converge, the second update data is generated and sent to the distribution system, otherwise the scheduling data is obtained.

[0136] For example, when the distribution system receives the initial Lagrange multipliers and initial boundary node data from the transmission system, the distribution part of the subproblem is solved. The solution process adopts g D (u D ,x D ,y D )=0 to constrain and obtain the first updated data Among them, u D is the control variable, x D is the state variable, y D is the state variable of the boundary node. When solving the distribution partial problem, the initial Lagrange multiplier is updated.

[0137] When the transmission system receives at least S first update data from the distribution center, solve the transmission part subproblem, through λ t+1 =λ t +η(h t+1 -h t ) Update the Lagrange multiplier; by stg T (u T ,x T ,y T )=0 to obtain the second updated data, where u T is the control variable, x T is the state variable, y T is the state variable of the boundary node.

[0138] Furthermore, as a preferred implementation manner, the calculating the power grid flow value according to the second updated data includes:

[0139] Acquire the voltage amplitude, voltage phase angle, active power and reactive power of the boundary node between the power transmission system and the power distribution system according to the second update data;

[0140] Calculating a first power flow value of the power transmission system according to the voltage amplitude and the voltage phase angle;

[0141] Calculating a second power flow value of each of the power distribution systems according to the active power and the reactive power;

[0142] A power grid power flow value is obtained according to the first power flow value and the second power flow value.

[0143] For example, by T φ ([V B θ B ])=[P B ′ ;Q ′ B ] calculate the first power flow value of the power transmission system; by D φ ([P B ;Q B ])=[V′ B θ′ B ] calculate the second power flow value of the power transmission system; wherein, P′ B is the active power; Q′ B is the reactive power; V′ B is the voltage amplitude; θ′ B is the voltage phase angle.

[0144] Preferably, determining the convergence of the power grid power flow value includes:

[0145] According to the power grid flow value, a spectrum radius index is calculated;

[0146] When the spectrum radius index is less than 1, it is determined that the power grid power flow value is converged; otherwise, it is determined that the power grid power flow value is not converged.

[0147] For example, by Get the spectral radius index, where T φ is the first power flow value of the transmission system; D φ is the second power flow value of the distribution system; x=[P B ;Q B ; V B θ B ].

[0148] An asynchronous power grid scheduling method for coordinated transmission and distribution provided in an embodiment of the present invention can significantly improve the overall computing efficiency and operational stability of the integrated transmission and distribution system by decomposing the computing tasks of the transmission system and the distribution system and using an asynchronous forward-backward operator splitting algorithm to handle the problems of the transmission system and the distribution system respectively.

[0149] See also Figure 4 The embodiment of the present invention provides an asynchronous power grid dispatching system for transmission and distribution coordination, including a data updating module 11, an iteration end judgment module 12, a data sending module 13 and a power grid dispatching module 14, wherein:

[0150] The data updating module 11 is used for, in the current iteration process, when receiving the first update data from at least S distribution systems, calculating the second update data by using the forward-backward operator splitting algorithm; the first update data and the second update data both include the boundary node data of the transmission system and the distribution system;

[0151] An iteration end judgment module 12 is used to calculate a power grid flow value according to the second updated data, and judge whether the power grid flow value meets the iteration end condition;

[0152] a data sending module 13, configured to send the second update data to the power distribution system if no, so that the power distribution system sends the first update data for the next iteration according to the second update data;

[0153] The power grid dispatching module 14 is used to obtain dispatching data according to the power grid flow value, and perform power grid dispatching according to the dispatching data.

[0154] As a preferred implementation, the data updating module 11 includes:

[0155] a previous iteration data acquisition unit, configured to acquire the second updated data in the previous iteration when receiving the first updated data from at least S power distribution systems;

[0156] The current iteration data updating unit is used to update the first update data according to the first update data and the second update data in the previous iteration by adopting a forward-backward operator splitting algorithm to obtain the second update data of the current iteration.

[0157] Further, preferably, if the current iteration is the first iteration, the previous iteration data acquisition unit is specifically used to:

[0158] Get initial boundary node data;

[0159] When the first update data from at least S power distribution systems is received, the initial boundary node data is used as the second update data in the previous iteration.

[0160] Preferably, the current iteration data updating unit is specifically used for:

[0161] Calculating a current global vector of a boundary node between the power transmission system and the power distribution system according to the first updated data and the second updated data in the previous iteration;

[0162] Calculating a power flow value of the power transmission system according to the current global vector;

[0163] According to the power flow value, the current global vector is updated by using a forward-backward operator splitting algorithm to obtain an updated global variable;

[0164] According to the updated global variable, the second updated data of the current iteration is obtained.

[0165] As a preferred implementation, the power grid dispatching system further includes:

[0166] A hysteresis step number acquisition module, used to acquire the hysteresis step number of each of the power distribution systems; the hysteresis step number of each of the power distribution systems is updated after each iteration;

[0167] A power distribution system screening module, used for selecting the power distribution system with the hysteresis step number not less than τ as a lagging power distribution system;

[0168] Then, the at least S power distribution systems include a lagging power distribution system.

[0169] Further, preferably, the method for updating the hysteresis step number of each of the power distribution systems comprises:

[0170] If the first update data received during the current iteration is from a power distribution system, resetting the hysteresis step number of the power distribution system after the current iteration;

[0171] If the first update data received in the current iteration does not come from a power distribution system, the hysteresis step number of the power distribution system is incremented after the current iteration.

[0172] As a preferred implementation, the iteration end judgment module 12 includes:

[0173] A power flow value calculation unit, configured to calculate a power grid power flow value according to the second updated data; the power grid power flow value includes a first power flow value of the power transmission system and a second power flow value of each of the power distribution systems;

[0174] A convergence determination unit, used to determine the convergence of the power grid power flow value;

[0175] A first convergence condition determination unit, configured to determine that the power grid flow value does not meet an iteration end condition if the power grid flow value does not converge;

[0176] The second convergence condition determination unit is configured to determine that, if the power grid power flow value converges, the power grid power flow value satisfies an iteration end condition.

[0177] Further, as a preferred implementation, the power flow value calculation unit is specifically used to:

[0178] Acquire the voltage amplitude, voltage phase angle, active power and reactive power of the boundary node between the power transmission system and the power distribution system according to the second update data;

[0179] Calculating a first power flow value of the power transmission system according to the voltage amplitude and the voltage phase angle;

[0180] Calculating a second power flow value of each of the power distribution systems according to the active power and the reactive power;

[0181] A power grid power flow value is obtained according to the first power flow value and the second power flow value.

[0182] Preferably, the convergence determination unit is specifically used to:

[0183] According to the power grid flow value, a spectrum radius index is calculated;

[0184] When the spectrum radius index is less than 1, it is determined that the power grid power flow value is converged; otherwise, it is determined that the power grid power flow value is not converged.

[0185] An asynchronous power grid dispatching system for coordinated transmission and distribution provided in an embodiment of the present invention is used to decompose the computing tasks of the transmission system and the distribution system, and use an asynchronous forward-backward operator splitting algorithm to handle the problems of the transmission system and the distribution system respectively, which can significantly improve the overall computing efficiency and operating stability of the integrated transmission and distribution system.

[0186] The embodiment of the present invention also provides an asynchronous power grid dispatching device for transmission and distribution coordination. The power grid dispatching device includes a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps in the above-mentioned various power grid dispatching method embodiments are implemented, such as steps S1 to S4.

[0187] Exemplarily, the computer program may be divided into one or more modules / units, which are stored in the memory and executed by the processor to complete the present invention. The one or more modules / units may be a series of computer program instruction segments capable of completing specific functions, which are used to describe the execution process of the computer program in the power grid dispatching device.

[0188] The power grid dispatching device may include, but is not limited to, a processor and a memory. Those skilled in the art will appreciate that the schematic diagram is merely an example of a power grid dispatching device and does not constitute a limitation on the power grid dispatching device. The power grid dispatching device may include more or fewer components than shown in the diagram, or may combine certain components, or different components. For example, the power grid dispatching device may also include input and output devices, network access devices, buses, etc.

[0189] The processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc. The processor is the control center of the power grid dispatching device, and uses various interfaces and lines to connect various parts of the entire power grid dispatching device.

[0190] The memory can be used to store the computer program and / or module, and the processor realizes various functions of the power grid dispatching device by running or executing the computer program and / or module stored in the memory, and calling the data stored in the memory. The memory can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, an application required for at least one function (such as a sound playback function, an image playback function, etc.), etc.; the data storage area can store data created according to the use of the mobile phone (such as audio data, a phone book, etc.), etc. In addition, the memory can include a high-speed random access memory, and can also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0191] Wherein, if the module / unit integrated in the power grid dispatching equipment is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on such an understanding, the present invention implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Wherein, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form, etc. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electric carrier signal, telecommunication signal and software distribution medium, etc.

[0192] A person skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium, and when the program is executed, it can include the processes of the embodiments of the above-mentioned methods. The storage medium can be a disk, an optical disk, a read-only memory (ROM) or a random access memory (RAM), etc.

[0193] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A transmission and distribution coordinated asynchronous power grid dispatching method, applied to a power transmission system, characterized in that: include: In the current iteration process, when first update data from at least S power distribution systems are received, a forward-backward operator splitting algorithm is used to calculate and obtain second update data; The first update data and the second update data both include boundary node data of the power transmission system and the power distribution system; Calculating a power grid flow value according to the second updated data, and determining whether the power grid flow value satisfies an iteration end condition; If not, sending the second update data to the power distribution system, so that the power distribution system sends out the first update data for the next iteration according to the second update data; If so, dispatching data is obtained according to the power grid flow value, and power grid dispatching is performed according to the dispatching data.

2. The method for dispatching an asynchronous power grid with coordinated transmission and distribution according to claim 1, characterized in that: In the current iteration process, when first update data from at least S power distribution systems is received, a forward-backward operator splitting algorithm is used to calculate and obtain second update data, including: In the current iteration, when first update data from at least S power distribution systems is received, the second update data in the previous iteration is obtained; According to the first update data and the second update data in the previous iteration, the first update data is updated using a forward-backward operator splitting algorithm to obtain the second update data of the current iteration.

3. The method for dispatching an asynchronous power grid with coordinated transmission and distribution according to claim 2, characterized in that: If the current iteration is the first iteration, in the current iteration, when first update data from at least S power distribution systems is received, obtaining the second update data in the previous iteration includes: Get initial boundary node data; In the current iteration, when the first update data from at least S power distribution systems is received, the initial boundary node data is used as the second update data in the previous iteration.

4. The method for dispatching an asynchronous power grid with coordinated transmission and distribution according to claim 2, characterized in that: The method of updating the first update data according to the first update data and the second update data in the previous iteration by using a forward-backward operator splitting algorithm to obtain the second update data of the current iteration includes: Calculating a current global vector of a boundary node between the power transmission system and the power distribution system based on the first updated data and the second updated data in the previous iteration; Calculating a power flow value of the power transmission system according to the current global vector; According to the power flow value, the current global vector is updated by using a forward-backward operator splitting algorithm to obtain an updated global variable; According to the updated global variable, the second updated data of the current iteration is obtained.

5. The method for dispatching an asynchronous power grid with coordinated transmission and distribution according to claim 1, characterized in that: In the current iteration process, when first update data from at least S distribution systems is received, before the forward-backward operator splitting algorithm is used to calculate the second update data, the power grid dispatching method further includes: Acquire the hysteresis step number of each power distribution system; the hysteresis step number of each power distribution system is updated after each iteration; The power distribution system with the hysteresis step number not less than τ is used as a hysteresis power distribution system; Then, the at least S power distribution systems include a lagging power distribution system.

6. The method for dispatching an asynchronous power grid with coordinated transmission and distribution according to claim 5, characterized in that: A method for updating the number of hysteresis steps of each of the power distribution systems comprises: If the first update data received during the current iteration is from a power distribution system, resetting the hysteresis step number of the power distribution system after the current iteration; If the first update data received in the current iteration does not come from a power distribution system, the hysteresis step number of the power distribution system is incremented after the current iteration.

7. The method for dispatching an asynchronous power grid with coordinated transmission and distribution according to claim 1, characterized in that: The calculating, according to the second updated data, a power grid flow value, and judging whether the power grid flow value satisfies an iteration end condition comprises: A power grid flow value is calculated according to the second updated data; the power grid flow value includes a first power flow value of the power transmission system and a second power flow value of each of the power distribution systems; Determining the convergence of the power grid flow value; If the power grid flow value does not converge, it is considered that the power grid flow value does not meet the iteration end condition; If the power grid flow value converges, it is considered that the power grid flow value meets the iteration end condition.

8. The transmission and distribution coordinated asynchronous power grid dispatching method according to claim 7, characterized in that: The calculating and obtaining the power grid flow value according to the second updated data includes: Acquire the voltage amplitude, voltage phase angle, active power and reactive power of the boundary node between the power transmission system and the power distribution system according to the second update data; Calculating a first power flow value of the power transmission system according to the voltage amplitude and the voltage phase angle; Calculating a second power flow value of each of the power distribution systems according to the active power and the reactive power; A power grid power flow value is obtained according to the first power flow value and the second power flow value.

9. The transmission and distribution coordinated asynchronous power grid dispatching method according to claim 7, characterized in that: The determining the convergence of the power grid flow value comprises: According to the power grid flow value, a spectrum radius index is calculated; When the spectrum radius index is less than 1, it is determined that the power grid power flow value is converged; otherwise, it is determined that the power grid power flow value is not converged.

10. An asynchronous power grid dispatching system for transmission and distribution coordination, characterized in that: include: A data updating module, configured to, in a current iteration process, when receiving first update data from at least S distribution systems, calculate second update data using a forward-backward operator splitting algorithm; the first update data and the second update data both include boundary node data of the transmission system and the distribution system; An iteration end judgment module, used to calculate a power grid flow value according to the second updated data, and judge whether the power grid flow value meets the iteration end condition; a data sending module, configured to send the second update data to the power distribution system if no, so that the power distribution system sends the first update data for the next iteration according to the second update data; The power grid dispatching module is used to obtain dispatching data according to the power grid flow value, and perform power grid dispatching according to the dispatching data.

11. The transmission and distribution coordinated asynchronous power grid dispatching system according to claim 10, characterized in that: The data updating module comprises: a previous iteration data acquisition unit, configured to acquire the second updated data in the previous iteration when receiving the first updated data from at least S power distribution systems; The current iteration data updating unit is used to update the first update data according to the first update data and the second update data in the previous iteration by adopting a forward-backward operator splitting algorithm to obtain the second update data of the current iteration.

12. The transmission and distribution coordinated asynchronous power grid dispatching system according to claim 11, characterized in that: The previous iteration data acquisition unit is specifically used for: Get initial boundary node data; When the first update data from at least S power distribution systems is received, the initial boundary node data is used as the second update data in the previous iteration.

13. The transmission and distribution coordinated asynchronous power grid dispatching system according to claim 11, characterized in that: The current iteration data updating unit is specifically used for: Calculating a current global vector of a boundary node between the power transmission system and the power distribution system based on the first updated data and the second updated data in the previous iteration; Calculating a power flow value of the power transmission system according to the current global vector; According to the power flow value, the current global vector is updated by using a forward-backward operator splitting algorithm to obtain an updated global variable; According to the updated global variable, the second updated data of the current iteration is obtained.

14. The transmission and distribution coordinated asynchronous power grid dispatching system according to claim 10, characterized in that: The power grid dispatching system also includes: A hysteresis step number acquisition module, used to acquire the hysteresis step number of each of the power distribution systems; the hysteresis step number of each of the power distribution systems is updated after each iteration; A power distribution system screening module, used for selecting the power distribution system with the hysteresis step number not less than τ as a lagging power distribution system; Then, the at least S power distribution systems include a lagging power distribution system.

15. The transmission and distribution coordinated asynchronous power grid dispatching system according to claim 14, characterized in that: A method for updating the number of hysteresis steps of each of the power distribution systems comprises: If the first update data received during the current iteration is from a power distribution system, resetting the hysteresis step number of the power distribution system after the current iteration; If the first update data received in the current iteration does not come from a power distribution system, the hysteresis step number of the power distribution system is incremented after the current iteration.

16. The transmission and distribution coordinated asynchronous power grid dispatching system according to claim 10, characterized in that: The iteration end judgment module includes: A power flow value calculation unit, configured to calculate a power grid power flow value according to the second updated data; the power grid power flow value includes a first power flow value of the power transmission system and a second power flow value of each of the power distribution systems; A convergence determination unit, used to determine the convergence of the power grid power flow value; A first convergence condition determination unit, configured to determine that the power grid flow value does not meet an iteration end condition if the power grid flow value does not converge; The second convergence condition determination unit is configured to determine that, if the power grid power flow value converges, the power grid power flow value satisfies an iteration end condition.

17. The transmission and distribution coordinated asynchronous power grid dispatching system according to claim 16, characterized in that: The power flow value calculation unit is specifically used for: Acquire the voltage amplitude, voltage phase angle, active power and reactive power of the boundary node between the power transmission system and the power distribution system according to the second update data; Calculating a first power flow value of the power transmission system according to the voltage amplitude and the voltage phase angle; Calculating a second power flow value of each of the power distribution systems according to the active power and the reactive power; A power grid power flow value is obtained according to the first power flow value and the second power flow value.

18. The transmission and distribution coordinated asynchronous power grid dispatching system according to claim 16, characterized in that: The convergence determination unit is specifically used for: According to the power grid flow value, a spectrum radius index is calculated; When the spectrum radius index is less than 1, it is determined that the power grid power flow value is converged; otherwise, it is determined that the power grid power flow value is not converged.

19. An asynchronous power grid dispatching device for transmission and distribution coordination, characterized in that: The method comprises a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein when the processor executes the computer program, the method for dispatching an asynchronous power grid with coordinated transmission and distribution as described in any one of claims 1 to 9 is implemented.

20. A computer-readable storage medium, characterized in that: The computer-readable storage medium includes a stored computer program, wherein when the computer program is executed, the device where the computer-readable storage medium is located is controlled to execute the asynchronous power grid dispatching method for transmission and distribution coordination as described in any one of claims 1 to 9.

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