Power distribution network power flow calculation method, calculation device and power distribution network power flow calculation system

Abstract

The application provides a power distribution network power flow calculation method, a power distribution network power flow calculation device and a power distribution network power flow calculation system. The method comprises the following steps: establishing a power distribution network power flow equation; in the case that any node in the power distribution network is disconnected, a first equation is established according to the voltage phase angle, the reactance and the initial power flow of each target branch, the target branch being an affected branch after the node is disconnected; a ratio of the power flow increment of the target branch to the initial power flow of the node is determined as a distribution factor; a second equation is established according to a vector composed of the distribution factors and an active power flow vector of the affected branch when the power distribution network is in a steady state; the power flow increment of the affected branch is calculated by simultaneously solving the power distribution network power flow equation, the first equation and the second equation; and the power distribution of the affected power equipment in the power distribution network is adjusted according to the power flow increment of the affected branch. The method solves the problem that the affected power equipment cannot be adjusted in time due to the low efficiency of the power flow calculation in the prior art.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of power system analysis, in particular to a power distribution network power flow calculation method, a power distribution network power flow calculation device, a computer readable storage medium, a computer program product and a power distribution network power flow calculation system. BACKGROUND

[0002] Due to the continuous improvement of industrialization and the increasing improvement of urban residents' living standards worldwide, the demand for electric energy continues to grow, further exacerbating energy crisis and environmental pollution problems. Achieving high proportion of renewable energy grid connection can alleviate energy crisis and environmental pollution problems, but increases the complexity and uncertainty of the safe and stable operation of active power distribution networks. In order to effectively prevent the above problems occurring in the operation of active power distribution networks, the safety and stability of active power distribution networks need to be evaluated in real time, quickly and accurately. Power flow calculation is the basis for analyzing the operating state of a power distribution network. Based on the topological structure and operating conditions of the network, the operating state of the power system is determined, such as the voltage amplitude of each node, the voltage phase angle of each node, the network power distribution and other operating conditions, which plays a very important role in power system reliability, safety, economy analysis, fault handling and network reconstruction.

[0003] The main power flow calculation method currently generally calculates the power flow transfer amount through a complex search algorithm, which usually needs to traverse the entire network to find a solution that satisfies the power flow equation. In a power distribution network, especially when the network structure is complex and the number of distributed power sources is large, the search algorithm needs to constantly update the network state and adjust the boundary conditions of the load and power source to solve the power flow distribution of the network. Although it can provide accurate power flow solution in theory, the calculation process involves a large number of search steps, especially when dealing with large-scale power grids or active power distribution networks with high proportion of renewable energy access, the calculation time increases significantly. Since the search algorithm requires a large number of search steps, the calculation process takes a long time, affecting the efficiency of power flow transfer amount calculation, so it is not possible to evaluate the electrical changes of the branch under disturbance or fault conditions in a timely manner, identify the lines or equipment that may bear additional load due to excessive current in a timely manner, and adjust the equipment or lines for prevention in a timely manner. SUMMARY

[0004] The main purpose of the present application is to provide a power distribution network power flow calculation method, a power distribution network power flow calculation device, a computer readable storage medium, a computer program product and a power distribution network power flow calculation system to at least solve the problem of low efficiency of power flow calculation in the prior art, which cannot adjust the affected power equipment in a timely manner.

[0005] In order to achieve the above object, according to one aspect of the present application, a power distribution network power flow calculation method is provided, comprising: establishing a power distribution network power flow equation, the power distribution network power flow equation comprising a common coupling node power flow equation, a load node power flow equation and a distributed power supply power flow equation, the common coupling node power flow equation being used to calculate complex power of a common coupling node in the power distribution network, the load node power flow equation being used to calculate complex power of a load node in the power distribution network, and the distributed power supply power flow equation being used to calculate complex power of a distributed power supply in the power distribution network; in the case of disconnection of any node in the power distribution network, a first equation is established according to voltage phase angle of each target branch, reactance of each target branch and initial power flow of each target branch, the target branch being an affected branch after disconnection of the node, the first equation being used to calculate power flow increment of the affected branch, and the initial power flow being power flow of the node or the target branch before disconnection of the node; a ratio of the power flow increment of the target branch to the initial power flow of the node is determined as a distribution factor of the target branch; a distribution factor vector is formed by the distribution factors of each target branch of the affected branch; a second equation is established according to the distribution factor vector and active power flow vector of the affected branch when the power distribution network is in a steady state, the second equation being used to calculate the power flow increment of the affected branch; the power flow increment of the affected branch is calculated by simultaneously solving the power distribution network power flow equation, the first equation and the second equation; and power distribution of an affected power equipment in the power distribution network is adjusted according to the power flow increment of the affected branch.

[0006] Optionally, the power distribution network power flow equation is established, and the power distribution network power flow equation comprises a common coupling node power flow equation, a load node power flow equation and a distributed power supply power flow equation, which comprises: establishing the common coupling node power flow equation wherein N is a total number of nodes in the power distribution network, Y ik is admittance of a branch of the node i and the node k, is a voltage vector of the node k, is a voltage vector of the node i, is complex power of the node i, is complex power generated by a generator of the node i, is complex power consumed by a load of the node i, is a voltage vector of the node r, V r sp is a known voltage value of the node r, G is a set of common coupling nodes in the power distribution network; the load node power flow equation is established wherein Y lk is admittance of a branch of the node l and the node k, is a voltage vector of the node l, the known injected active power for the load node l, the known injected reactive power for the load node l, P Ll the consumed active power for the load node l, Q Ll the consumed reactive power for the load node k, the complex power emitted by the generator of node l, the complex power consumed by the load of node l, L is a set of load nodes in the power distribution network; a distributed power flow equation is established wherein, Y mk the admittance of the branch of node m and node k, the voltage vector of node m, the complex power emitted by the generator of node m, the complex power consumed by the load of node m, the known injected active power for node m, the known injected reactive power for node m.

[0007] Optionally, in the case of disconnection of any node in the power distribution network, a first equation is established according to the voltage phase angle of each target branch, the reactance of each target branch and the initial flow of each target branch, comprising: a first equation is established according to the voltage phase angle of each target branch, the reactance of each target branch and the initial flow of each target branch wherein, m is the total number of the affected branches, the flow of branch k after node l is disconnected, P k the initial flow of branch k, θ' k the voltage phase angle of branch k, x k the reactance of branch k, ΔP is the flow increment of the affected branch.

[0008] Optionally, the ratio of the flow increment of the target branch to the initial flow of the node is determined as the distribution factor of the target branch, comprising: the distribution factor is determined wherein, ΔP k the flow increment of branch k after node l is disconnected, P l the initial flow of node l.

[0009] Optionally, a second equation is established according to the distribution factor vector and the active power flow vector of the affected branch when the power distribution network is in a steady state, comprising: in the case of disconnection of the node, the admittance matrix of the power distribution network is calculated, and the admittance matrix is wherein, B0 is the admittance matrix of the power distribution network before the node is disconnected, A Δ the correlation matrix composed of the correlation vector of the affected branch, a branch admittance variation matrix of branches connected to the node before the node is disconnected; calculating, according to the admittance matrix of the power distribution network, an active power flow column vector P of the affected branches when the power distribution network is in a steady state ml = B'θ, wherein θ is a voltage phase angle vector of the node; establishing a second equation ΔP k = D k P ml , wherein D k is the distribution factor vector, and P ml is the active power flow vector of the affected branches when the power distribution network is in a steady state.

[0010] Optionally, the power distribution of the affected power equipment in the power distribution network is adjusted according to the power flow increment of the affected branch, including: in the case that the power flow increment of the affected branch exceeds a predetermined threshold, the power distribution of the affected power equipment in the power distribution network is adjusted.

[0011] According to another aspect of the present application, there is provided a power distribution network power flow calculation device, comprising: a first establishing unit configured to establish a power distribution network power flow equation, the power distribution network power flow equation comprising a common coupling node power flow equation, a load node power flow equation and a distributed power supply power flow equation, the common coupling node power flow equation being configured to calculate complex power of a common coupling node in the power distribution network, the load node power flow equation being configured to calculate complex power of a load node in the power distribution network, and the distributed power supply power flow equation being configured to calculate complex power of a distributed power supply in the power distribution network; a second establishing unit configured to, in the case that any node in the power distribution network is disconnected, establish a first equation according to voltage phase angles of each target branch, reactance of each target branch and initial power flow of each target branch, the target branch being an affected branch after the node is disconnected, the first equation being configured to calculate power flow increment of the affected branch, and the initial power flow being power flow of the node or the target branch before the node is disconnected; a first determining unit configured to determine a ratio of the power flow increment of the target branch and the initial power flow of the node as a distribution factor of the target branch; a third establishing unit configured to form a distribution factor vector by using the distribution factors of each target branch of the affected branch; a fourth establishing unit configured to establish a second equation according to the distribution factor vector and an active power flow vector of the affected branch when the power distribution network is in a steady state, the second equation being configured to calculate the power flow increment of the affected branch; a first calculating unit configured to calculate the power flow increment of the affected branch by simultaneously solving the power distribution network power flow equation, the first equation and the second equation; and a first control unit configured to adjust power distribution of affected power equipment in the power distribution network according to the power flow increment of the affected branch.

[0012] According to still another aspect of the present application, there is provided a computer readable storage medium including a stored program, wherein the program, when executed, controls any of the methods described above in any of the devices in which the computer readable storage medium is present.

[0013] According to still another aspect of the present application, there is provided a computer program product including a computer program, wherein the computer program, when executed by a processor, implements any of the methods described above.

[0014] According to still another aspect of the present application, there is provided a power distribution network power flow calculation system including one or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, and the one or more programs include instructions for performing any of the methods described above.

[0015] The technical scheme is applied to the power distribution network power flow calculation method, and comprises the following steps: establishing a power distribution network power flow equation, the power distribution network power flow equation comprising a public coupling node power flow equation, a load node power flow equation and a distributed power supply power flow equation, the public coupling node power flow equation being used to calculate complex power of a public coupling node in the power distribution network, the load node power flow equation being used to calculate complex power of a load node in the power distribution network, and the distributed power supply power flow equation being used to calculate complex power of a distributed power supply in the power distribution network; in the case that any node in the power distribution network is disconnected, a first equation is established according to voltage phase angles of each target branch, reactance of each target branch and initial power flow of each target branch, the target branch being an affected branch after the node is disconnected, the first equation being used to calculate power flow increment of the affected branch, and the initial power flow being power flow of the node or the target branch before the node is disconnected; a ratio of the power flow increment of the target branch and the initial power flow of the node is determined as a distribution factor of the target branch; a distribution factor vector is formed by the distribution factors of each target branch of the affected branch; a second equation is established according to the distribution factor vector and active power flow vector of the affected branch when the power distribution network is in a steady state, the second equation being used to calculate the power flow increment of the affected branch; the power flow increment of the affected branch is calculated by simultaneously solving the power distribution network power flow equation, the first equation and the second equation; and power distribution of an affected power device in the power distribution network is adjusted according to the power flow increment of the affected branch. The power distribution network power flow equation is established to calculate complex power of the public coupling node, the load node and the distributed power supply in the power distribution network, the power flow increment of the affected branch after the node is disconnected in the power distribution network is calculated by simultaneously solving the power distribution network power flow equation, the first equation and the second equation, and power distribution of the affected power device is adjusted in time according to the power flow increment, thereby avoiding overloading of the line and affecting normal operation of the power distribution network, and solving the problem that the affected power device cannot be adjusted in time due to low power flow calculation efficiency in the prior art. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 A hardware structure block diagram of a mobile terminal showing a power distribution network power flow calculation method provided in an embodiment of the application is shown;

[0017] Figure 2 A flowchart showing a power distribution network power flow calculation method provided in an embodiment of the application is shown;

[0018] Figure 3 A structure block diagram of a power distribution network power flow calculation device provided in an embodiment of the application is shown.

[0019] In the drawings, the following reference signs are used:

[0020] 102, processor; 104, memory; 106, transmission device; 108, input and output device. DETAILED DESCRIPTION

[0021] It should be noted that the embodiments and features in the present application can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0022] In order for those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should be within the scope of protection of the present application.

[0023] It should be noted that the terms "first", "second" and the like in the specification and claims of the present application and the above-described drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or a chronological sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0024] As introduced in the background, the calculation process of the existing power flow calculation is time-consuming, which affects the efficiency of the power flow transfer calculation, and cannot identify the line or device that may bear additional load due to excessive current in time. To solve this technical problem, the embodiments of the present application provide a power distribution network power flow calculation method, a calculation device, a computer readable storage medium, a computer program product and a power distribution network power flow calculation system.

[0025] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings.

[0026] The method embodiments provided in the embodiments of the present application can be executed in a mobile terminal, a computer terminal or a similar computing device. Taking the case of running on a mobile terminal, Figure 1 is a hardware structure diagram of a mobile terminal of a power distribution network power flow calculation method according to an embodiment of the present application. As shown in Figure 1 , the mobile terminal can include one or more Figure 1The mobile terminal can further include a transmission device 106 for communication function and an input / output device 108. Those skilled in the art can understand that, Figure 1 The structure shown is only schematic and does not limit the structure of the mobile terminal. For example, the mobile terminal can include more or less components than those shown, or have a different configuration or arrangement of the components. Figure 1 The mobile terminal can include more or less components than those shown, or have a different configuration or arrangement of the components. Figure 1 The mobile terminal can include more or less components than those shown, or have a different configuration or arrangement of the components.

[0027] The memory 104 can be used to store computer programs, such as software programs and modules of application software, and a computer program corresponding to the power grid power flow calculation method of the embodiment of the present application. The processor 102 can execute various functional applications and data processing by running the computer program stored in the memory 104, i.e. implement the method described above. The memory 104 can include a high-speed random access memory, and can further include a non-volatile memory, such as one or more magnetic storage devices, flash memories, or other non-volatile solid-state memories. In some examples, the memory 104 can further include a memory remotely arranged with respect to the processor 102, which can be connected to the mobile terminal through a network. Examples of the network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and a combination thereof. The transmission device 106 is used to receive or send data via a network. The specific examples of the network can include a wireless network provided by a communication provider of the mobile terminal. In one example, the transmission device 106 includes a network adapter (NIC), which can be connected to other network devices through a base station so as to communicate with the Internet. In one example, the transmission device 106 can be a radio frequency (RF) module, which is used to communicate with the Internet in a wireless manner.

[0028] In the embodiment, a power grid power flow calculation method running on a mobile terminal, a computer terminal or a similar computing device is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0029] Figure 2 is a flowchart of a power grid power flow calculation method according to an embodiment of the present application. As Figure 2 shown, the method includes the following steps:

[0030] Step S201, establish the power flow equation of the power distribution network, the power flow equation of the power distribution network includes the power flow equation of the public coupling node, the power flow equation of the load node and the power flow equation of the distributed power supply, the power flow equation of the public coupling node is used to calculate the complex power of the public coupling node in the power distribution network, the power flow equation of the load node is used to calculate the complex power of the load node in the power distribution network, and the power flow equation of the distributed power supply is used to calculate the complex power of the distributed power supply in the power distribution network;

[0031] Specifically, the power flow equation of the power distribution network is established to calculate the power balance relationship of the public coupling node, the load node and the distributed power supply in the power distribution network. By calculating the complex power of the public coupling node, the load node and the distributed power supply, the power flow of each part in the power system can be determined, so as to realize the monitoring of the operation of the power distribution network and provide a basis for subsequent analysis of the power flow distribution.

[0032] Step S202, in the case that any node in the power distribution network is disconnected, a first equation is established according to the voltage phase angle of each target branch, the reactance of each target branch and the initial power flow of each target branch, the target branch is the affected branch after the node is disconnected, the first equation is used to calculate the power flow increment of the affected branch, and the initial power flow is the power flow of the node or the target branch before the node is disconnected;

[0033] Specifically, in the case that a node in the power distribution network is disconnected, the branch connected with the node will be affected. The affected branch is regarded as a target branch, and an equation is established according to the voltage phase angle, the reactance and the initial power flow of each target branch, which is used to calculate the power flow increment of the target branch, so as to help analyze the power flow change of the affected branch after the node is disconnected, thereby evaluating the stability of the power distribution network.

[0034] Step S203, determining the distribution factor of the target branch as the ratio of the power flow increment of the target branch to the initial power flow of the node;

[0035] Specifically, by calculating the ratio of the power flow increment of the target branch to the initial power flow of the node, the distribution factor of the target branch can be determined. The distribution factor reflects the influence degree of the node disconnection on different branches. When the distribution factor is large, it indicates that the branch is greatly affected by the node disconnection. By calculating the distribution factors of different branches, the stability of the system can be more comprehensively evaluated.

[0036] Step S204, forming a distribution factor vector by using the distribution factors of each target branch of the affected branch;

[0037] Specifically, by combining the distribution factors of each target branch of the affected branch into a distribution factor vector, the degree of influence of each branch in the entire system in the case of node disconnection can be more comprehensively described, and the distribution factor vector plays an auxiliary role in subsequent calculation of the power flow increment of the affected branch.

[0038] In step S205, a second equation is established according to the distribution factor vector and the active power flow vector of the affected branch in the steady state of the power distribution network, and the second equation is used to calculate the power flow increment of the affected branch.

[0039] Specifically, the distribution factor vector and the active power flow vector of the affected branch in the steady state are used to establish a second equation for calculating the power flow increment of the affected branch, which can help analyze the size of the power flow increment of the affected branch in the case of node disconnection, and provide information for subsequent solution of the power flow increment by calculating the power flow increment.

[0040] In step S206, the power flow increment of the affected branch is calculated by simultaneously solving the power flow equation of the power distribution network, the first equation and the second equation.

[0041] Specifically, by simultaneously solving the power flow equation of the power distribution network, the first equation and the second equation, the power flow increment of the affected branch can be calculated, and the impact of node disconnection on the affected branch of the power distribution network is comprehensively considered.

[0042] In step S207, the power distribution of the affected power equipment in the power distribution network is adjusted according to the power flow increment of the affected branch.

[0043] Specifically, according to the calculation result of the power flow increment of the affected branch, the power equipment or branch with greater influence can be identified, and the power distribution thereof is adjusted to reduce the power flow load and reduce the risk of overload, optimize the system operation, and help the system operator to adjust the system operation state in time to ensure that each equipment works in a safe and reliable range.

[0044] In the power distribution network power flow calculation method, a power distribution network power flow equation is established, the power distribution network power flow equation includes a public coupling node power flow equation, a load node power flow equation and a distributed power supply power flow equation, the public coupling node power flow equation is used to calculate the complex power of the public coupling node in the power distribution network, the load node power flow equation is used to calculate the complex power of the load node in the power distribution network, and the distributed power supply power flow equation is used to calculate the complex power of the distributed power supply in the power distribution network; in the case that any node in the power distribution network is disconnected, a first equation is established according to the voltage phase angle of each target branch, the reactance of each target branch and the initial power flow of each target branch, the target branch is an affected branch after the node is disconnected, the first equation is used to calculate the power flow increment of the affected branch, and the initial power flow is the power flow of the node or the target branch before the node is disconnected; the ratio of the power flow increment of the target branch to the initial power flow of the node is determined as the distribution factor of the target branch; the distribution factor vector is composed of the distribution factors of each target branch of the affected branch; a second equation is established according to the distribution factor vector and the active power flow vector of the affected branch when the power distribution network is in a steady state, the second equation is used to calculate the power flow increment of the affected branch; the power flow increment of the affected branch is calculated by simultaneously solving the power distribution network power flow equation, the first equation and the second equation; and the power distribution of the affected power equipment in the power distribution network is adjusted according to the power flow increment of the affected branch. The application calculates the complex power of the public coupling node, the load node and the distributed power supply in the power distribution network by establishing the power distribution network power flow equation, calculates the power flow increment of the affected branch after the node is disconnected in the power distribution network by simultaneously solving the power distribution network power flow equation, the first equation and the second equation, and adjusts the power distribution of the affected power equipment in time according to the power flow increment, thereby avoiding the overload of the line and affecting the normal operation of the power distribution network, and solving the problem that the affected power equipment cannot be adjusted in time due to the low efficiency of the power flow calculation in the prior art.

[0045] In order to further determine the power distribution network power flow equation, in an optional embodiment, a power distribution network power flow equation is established, the power distribution network power flow equation includes a public coupling node power flow equation, a load node power flow equation and a distributed power supply power flow equation, and the step S201 includes:

[0046] Step S2011, establishing a public coupling node power flow equation Wherein, N is the total number of nodes in the power distribution network, Y ik is the admittance of the branch of node i and node k, is the voltage vector of node k, is the voltage vector of node i, the complex power generated by the generator of node i, the complex power generated by the generator of node i, the complex power consumed by the load of node i, the voltage vector of node r, V r sp the known voltage assignment of node r, G is the set of the public coupling nodes in the power distribution network;

[0047] Specifically, the public coupling node power flow equation is established to describe the power relationship between the nodes in the power distribution network, and each node is connected through the admittance of the branch. In the public coupling node power flow equation, the power generated by the generator, the power consumed by the load, and the known voltage assignment of the node are considered, and the power flow characteristics between the nodes in the power distribution network are described.

[0048] Step S2012, establishing a load node power flow equation wherein Y lk the admittance of the branch between node l and node k, the voltage vector of node l, the known active power injected by the load node l, the known reactive power injected by the load node l, P Ll the active power consumed by the load node l, Q Ll the reactive power consumed by the load node k, the complex power generated by the generator of node l, the complex power consumed by the load of node l, L is the set of the load nodes in the power distribution network;

[0049] Specifically, the load node power flow equation is established to describe the power relationship between the load nodes in the power distribution network. By considering the admittance of the branch, the voltage vector of the node, and the active power and reactive power injected by each node, the active power and reactive power consumed by the node can be calculated, and the load node power flow equation describes the power flow characteristics between the load nodes.

[0050] Step S2013, establishing a distributed power supply power flow equation wherein Y mk the admittance of the branch between node m and node k, the voltage vector of node m, the complex power generated by the generator of node m, the complex power consumed by the load of node m, the known active power injected by node m, the known reactive power injected by node m.

[0051] Specifically, the distributed power flow equation is established to describe the power relationship between the distributed power nodes in the distribution network. By considering the admittance of the branch, the voltage vector of the node, and the power generated by the node generator, the power consumed by the load, and the known active power and reactive power injection, the power flow characteristics of the distributed power nodes can be calculated.

[0052] To obtain the first equation, in an optional embodiment, the first equation is established according to the voltage phase angle of each target branch, the reactance of each target branch, and the initial flow of each target branch when any node in the above distribution network is disconnected, and the step S202 includes:

[0053] Step S2021, the first equation is established according to the voltage phase angle of each target branch, the reactance of each target branch, and the initial flow of each target branch Wherein, m is the total number of the affected branches, P is the flow of branch k after node l is disconnected, k P is the initial flow of branch k, k is the voltage phase angle of branch k, k is the reactance of branch k, and

[0054] Specifically, the first equation is established based on the voltage phase angle, the reactance, and the initial flow of the affected branch, in which the number of affected branches, the change of the flow of each branch after the node is disconnected, the initial flow, the voltage phase angle, and the reactance of each branch are considered. The flow increment of all affected branches is calculated, and the calculation of the flow increment helps to evaluate the impact of the node disconnection on the entire system.

[0055] To obtain the distribution factor, in an optional embodiment, the ratio of the flow increment of the target branch to the initial flow of the node is determined as the distribution factor of the target branch, and the step S203 includes:

[0056] Step S2031, the distribution factor is determined Wherein, ΔP k P is the flow increment of branch k after node l is disconnected, l is the initial flow of node l.

[0057] Specifically, in the process of determining the distribution factor, the ratio of the flow increment of each branch to the initial flow of the node needs to be calculated, which is an important parameter for measuring the influence degree of the change of the flow of each branch after the node is disconnected.

[0058] To obtain the second equation, in an alternative embodiment, the second equation is established according to the distribution factor vector and the active power flow vector of the affected branch when the power distribution network is in a steady state, and the step S205 comprises:

[0059] In the case of the node being disconnected, the step S2051 comprises calculating a susceptance matrix of the power distribution network, wherein the susceptance matrix is wherein B0 is a susceptance matrix of the power distribution network before the node is disconnected, A Δ is a correlation matrix composed of the correlation vectors of the affected branch, is a branch susceptance variation matrix of the branch where the node is located before the node is disconnected; and

[0060] Specifically, in the case of the node being disconnected, it is necessary to recalculate the susceptance matrix of the power distribution network, and the new susceptance matrix can be calculated by the original susceptance matrix, the correlation matrix composed of the correlation vectors of the affected branch, and the branch susceptance variation matrix of the branch where the node is located before the node is disconnected. The susceptance matrix describes the electrical connection relationship between the nodes in the system.

[0061] In the case of the node being disconnected, the step S2052 comprises calculating the active power flow column vector P ml of the affected branch when the power distribution network is in a steady state according to the susceptance matrix of the power distribution network, wherein P

[0062] Specifically, the active power flow vector of the affected branch in the steady state can be calculated by using the susceptance matrix of the power distribution network. The active power flow vector can be calculated by the voltage phase angle vector of the node and the susceptance matrix, and is used to describe the current transmission in the affected branch.

[0063] In the case of the node being disconnected, the step S2053 comprises establishing a second equation ΔP k = D k P ml , wherein D k is the distribution factor vector, and P ml is the active power flow vector of the affected branch when the power distribution network is in a steady state.

[0064] Specifically, the second equation is established to calculate the power flow increment of the affected branch. The distribution factor vector is a parameter considering the influence degree of the node being disconnected on the power flow of each branch, and the active power flow vector of the affected branch describes the current transmission in the affected branch. By the equation, the distribution factor and the active power flow vector can be considered comprehensively to calculate the power flow increment of the affected branch, help to analyze the change of the electrical parameters of the system in the case of the node being disconnected, provide a decision basis for the system operator, help the system operator to find problems in time, make adjustments, and prevent potential faults and accidents.

[0065] To adjust the power distribution equipment in the power distribution network according to the power flow increment, in an optional implementation, the power distribution of the affected power equipment in the power distribution network is adjusted according to the power flow increment of the affected branch described above, and the step S207 includes:

[0066] Step S2071, if the power flow increment of the affected branch exceeds a predetermined threshold, the power distribution of the affected power equipment in the power distribution network is adjusted.

[0067] Specifically, when the power flow increment of the affected branch exceeds the predetermined threshold, the power distribution of the affected power equipment needs to be adjusted. By adjusting the power distribution of the affected power equipment, the load of the affected branch can be reduced, the current can be reduced, the overload problem can be avoided, the operation state of the power system can be optimized, the reliability of the system can be improved, the risk of system failure can be reduced, and stable power supply of the power system can be ensured.

[0068] It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from here.

[0069] The embodiment of the present application also provides a power distribution network power flow calculation device. It should be noted that the power distribution network power flow calculation device of the embodiment of the present application can be used to execute the power distribution network power flow calculation method provided by the embodiment of the present application. The device is used to realize the above-mentioned embodiments and preferred embodiments, which have been described. As used below, the term "module" can be a combination of software and / or hardware that implements a predetermined function. Although the device described in the following embodiments is preferably implemented in software, hardware, or a combination of software and hardware implementation is also possible and is contemplated.

[0070] The following describes a power distribution network power flow calculation device provided by the embodiment of the present application.

[0071] Figure 3 is a structural block diagram of a power distribution network power flow calculation device according to the embodiment of the present application. As Figure 3 shown, the device includes:

[0072] The first establishing unit 10 is configured to establish a power flow equation of the power distribution network, wherein the power flow equation of the power distribution network comprises a common coupling node power flow equation, a load node power flow equation and a distributed power supply power flow equation, the common coupling node power flow equation is used to calculate complex power of a common coupling node in the power distribution network, the load node power flow equation is used to calculate complex power of a load node in the power distribution network, and the distributed power supply power flow equation is used to calculate complex power of a distributed power supply in the power distribution network.

[0073] Specifically, the power flow equation of the power distribution network is established to calculate the power balance relationship of the common coupling node, the load node and the distributed power supply in the power distribution network. By calculating the complex power of the common coupling node, the load node and the distributed power supply, the power flow of each part in the power system can be determined, thereby monitoring the operation of the power distribution network and providing a basis for subsequent analysis of the power flow distribution.

[0074] The second establishing unit 20 is configured to, in the case that any node in the power distribution network is disconnected, establish a first equation according to voltage phase angles of each target branch, reactance of each target branch and initial power flow of each target branch, the target branch is an affected branch after the node is disconnected, the first equation is used to calculate power flow increment of the affected branch, and the initial power flow is power flow of the node or the target branch before the node is disconnected.

[0075] Specifically, in the case that a node in the power distribution network is disconnected, the branch connected to the node will be affected. The affected branch is regarded as a target branch, and an equation is established according to the voltage phase angle, the reactance and the initial power flow of each target branch, which is used to calculate the power flow increment of the target branch, thereby helping to analyze the power flow change of the affected branch after the node is disconnected, and evaluating the stability of the power distribution network.

[0076] The first determining unit 30 is configured to determine a distribution factor of the target branch as a ratio of the power flow increment of the target branch to the initial power flow of the node.

[0077] Specifically, by calculating the ratio of the power flow increment of the target branch to the initial power flow of the node, the distribution factor of the target branch can be determined. The distribution factor reflects the influence degree of the node disconnection on different branches. When the distribution factor is large, it indicates that the branch is greatly affected by the node disconnection. By calculating the distribution factors of different branches, the stability of the system can be more comprehensively evaluated.

[0078] The third establishing unit 40 is configured to form a distribution factor vector by using the distribution factors of the target branches of the affected branch.

[0079] Specifically, by combining the distribution factors of each target branch of the affected branch into a distribution factor vector, the degree of influence of each branch in the entire system in the case of node disconnection can be more comprehensively described, and the distribution factor vector plays an auxiliary role in subsequent calculation of the power flow increment of the affected branch.

[0080] The first establishment unit 50 is configured to establish a second equation according to the distribution factor vector and the active power flow vector of the affected branch in the steady state of the power distribution network, and the second equation is used to calculate the power flow increment of the affected branch.

[0081] Specifically, the second equation is established by using the distribution factor vector and the active power flow vector of the affected branch in the steady state, and is used to calculate the power flow increment of the affected branch. This equation can help analyze the size of the power flow increment of the affected branch in the case of node disconnection, and provide information for subsequent solution of the power flow increment by calculating the power flow increment.

[0082] The first calculation unit 60 is configured to calculate the power flow increment of the affected branch by simultaneously solving the power flow equation of the power distribution network, the first equation and the second equation.

[0083] Specifically, by simultaneously solving the power flow equation of the power distribution network, the first equation and the second equation, the power flow increment of the affected branch can be calculated. This calculation process will comprehensively consider the influence of node disconnection on the affected branch of the power distribution network.

[0084] The first control unit 70 is configured to adjust the power distribution of the affected power equipment in the power distribution network according to the power flow increment of the affected branch.

[0085] Specifically, according to the calculation result of the power flow increment of the affected branch, the power equipment or branch with greater influence can be identified, and then the power distribution thereof is adjusted to reduce the power flow load and reduce the risk of overload, optimize the system operation, and help the system operator to adjust the system operation state in time to ensure that each equipment works in a safe and reliable range.

[0086] By the embodiment, the first establishing unit is configured to establish power flow equations of the power distribution network, the power flow equations of the power distribution network including a common coupling node power flow equation, a load node power flow equation and a distributed power supply power flow equation, the common coupling node power flow equation being configured to calculate complex power of a common coupling node in the power distribution network, the load node power flow equation being configured to calculate complex power of a load node in the power distribution network, and the distributed power supply power flow equation being configured to calculate complex power of a distributed power supply in the power distribution network; the second establishing unit is configured to, in a case where any one node in the power distribution network is disconnected, establish a first equation according to voltage phase angles of target branches, reactances of the target branches and initial power flow amounts of the target branches, the target branches being affected branches after the node is disconnected, the first equation being configured to calculate power flow increments of the affected branches, and the initial power flow amounts being power flow amounts of the node or the target branches before the node is disconnected; the first determining unit is configured to determine distribution factors of the target branches as ratios of the power flow increments of the target branches to the initial power flow amounts of the node; the third establishing unit is configured to form a distribution factor vector by using the distribution factors of the target branches of the affected branches; the fourth establishing unit is configured to establish a second equation according to the distribution factor vector and an active power flow vector of the affected branches when the power distribution network is in a steady state, the second equation being configured to calculate the power flow increments of the affected branches; the first calculating unit is configured to calculate the power flow increments of the affected branches by simultaneously solving the power flow equations of the power distribution network, the first equation and the second equation; and the first control unit is configured to adjust power distribution of affected power equipment in the power distribution network according to the power flow increments of the affected branches. The application calculates complex power of a common coupling node, a load node and a distributed power supply in a power distribution network by establishing power flow equations of the power distribution network, calculates power flow increments of affected branches after a node in the power distribution network is disconnected by simultaneously solving the power flow equations of the power distribution network, a first equation and a second equation, and adjusts power distribution of affected power equipment in time according to the power flow increments, thereby avoiding overloading of lines and affecting normal operation of the power distribution network, and solving the problem that affected power equipment cannot be adjusted in time due to low efficiency of power flow calculation in the prior art.

[0087] To further determine the power flow equations of the power distribution network, in an alternative embodiment, the power flow equations of the power distribution network are established, the power flow equations of the power distribution network including a common coupling node power flow equation, a load node power flow equation and a distributed power supply power flow equation, and the first establishing unit includes:

[0088] The first establishing module is configured to establish the common coupling node power flow equation wherein N is a total number of nodes in the power distribution network, Y ik is admittance of a branch between node i and node k, a voltage vector of the node k, a voltage vector of the node i, a complex power of the node i, a complex power generated by a generator of the node i, a complex power consumed by a load of the node i, a voltage vector of the node r, V r sp a known voltage assignment of the node r, G is a set of the public coupling nodes in the power distribution network;

[0089] Specifically, the public coupling node power flow equation is established to describe the power relationship between the nodes in the power distribution network, and each node is connected through the admittance of the branch. In the public coupling node power flow equation, the power generated by the generator, the power consumed by the load, and the known voltage assignment of the node are considered, and the power flow characteristics between the nodes in the power distribution network are described.

[0090] The second establishing module is configured to establish a load node power flow equation wherein, Y lk is an admittance of a branch between the node l and the node k, a voltage vector of the node l, a known active power injected by the load node l, a known reactive power injected by the load node l, P Ll is an active power consumed by the load node l, Q Ll is a reactive power consumed by the load node k, a complex power generated by a generator of the node l, a complex power consumed by a load of the node l, L is a set of the load nodes in the power distribution network;

[0091] Specifically, the load node power flow equation is established to describe the power relationship between the load nodes in the power distribution network. By considering the admittance of the branch, the voltage vector of the node, and the active power and the reactive power injected by each node, the active power and the reactive power consumed by the node can be calculated. The load node power flow equation describes the power flow characteristics between the load nodes.

[0092] The third establishing module is configured to establish a distributed power supply power flow equation wherein, Y mk is an admittance of a branch between the node m and the node k, a voltage vector of the node m, a complex power generated by a generator of the node m, a complex power consumed by a load of the node m, a known active power injected by the node m, a known reactive power injected by the node m.

[0093] Specifically, the distributed power flow equation is established to describe the power relationship between the distributed power nodes in the distribution network. By considering the admittance of the branch, the voltage vector of the node, and the power generated by the node generator, the power consumed by the load, and the known active power and reactive power injection, the power flow characteristics of the distributed power nodes can be calculated.

[0094] To obtain the first equation, in an optional embodiment, the first equation is established according to the voltage phase angle of each target branch, the reactance of each target branch, and the initial power flow of each target branch when any node in the above distribution network is disconnected, and the second establishing unit comprises:

[0095] The first establishing module is configured to establish the first equation according to the voltage phase angle of each target branch, the reactance of each target branch, and the initial power flow of each target branch Wherein, m is the total number of the affected branches, P is the power flow of branch k after node l is disconnected, k θ' is the initial power flow of branch k, k x is the voltage phase angle of branch k, k x is the voltage phase angle of branch k, k ΔP is the power flow increment of the affected branch.

[0096] Specifically, the first equation is established based on the voltage phase angle, the reactance, and the initial power flow of the affected branch, in which the number of affected branches, the change of the power flow of each branch after the node is disconnected, the initial power flow, the voltage phase angle, and the reactance of each branch are considered. The power flow increment of all affected branches is calculated, and the calculation of the power flow increment helps to evaluate the impact of node disconnection on the entire system.

[0097] To obtain the distribution factor, in an optional embodiment, the ratio of the power flow increment of the target branch to the initial power flow of the node is determined as the distribution factor of the target branch, and the first determining unit comprises:

[0098] The first determining module is configured to determine the distribution factor Wherein, ΔP k P is the power flow increment of branch k after node l is disconnected, l P is the initial power flow of node l.

[0099] Specifically, in the process of determining the distribution factor, it is necessary to calculate the ratio of the power flow increment of each branch to the initial power flow of the node. This ratio is an important parameter for measuring the degree of influence of the node disconnection on the change of the power flow of each branch.

[0100] To obtain the second equation, in an alternative embodiment, the second equation is established according to the distribution factor vector and the active power flow vector of the affected branch when the power distribution network is in a steady state, and the first establishing unit comprises:

[0101] The fifth establishing module is configured to calculate a susceptance matrix of the power distribution network in the case of the node being disconnected, and the susceptance matrix is wherein B0 is a susceptance matrix of the power distribution network before the node is disconnected, A Δ is a correlation matrix composed of the correlation vectors of the affected branch, is a branch susceptance variation matrix of the branch where the node is located before the node is disconnected;

[0102] Specifically, in the case of the node being disconnected, it is necessary to recalculate the susceptance matrix of the power distribution network, and the new susceptance matrix can be calculated by the original susceptance matrix, the correlation matrix composed of the correlation vectors of the affected branch, and the branch susceptance variation matrix of the branch where the node is located before the node is disconnected. The susceptance matrix describes the electrical connection relationship between the nodes in the system.

[0103] The sixth establishing module is configured to calculate the active power flow column vector P ml of the affected branch when the power distribution network is in a steady state according to the susceptance matrix of the power distribution network, wherein θ is a voltage phase angle vector of the node.

[0104] Specifically, the active power flow vector of the affected branch in a steady state can be calculated by using the susceptance matrix of the power distribution network. The active power flow vector can be calculated by the voltage phase angle vector of the node and the susceptance matrix, and is used to describe the current transmission in the affected branch.

[0105] The seventh establishing module establishes a second equation ΔP k = D k P ml , wherein D k is the distribution factor vector, and P ml is the active power flow vector of the affected branch when the power distribution network is in a steady state.

[0106] Specifically, the second equation is established to calculate the power flow increment of the affected branch. The distribution factor vector is a parameter considering the influence degree of the node being disconnected on the power flow of each branch, and the active power flow vector of the affected branch describes the current transmission in the affected branch. By the equation, the distribution factor and the active power flow vector can be considered comprehensively to calculate the power flow increment of the affected branch, help to analyze the change of the electrical parameters of the system in the case of the node being disconnected, provide a decision basis for the system operator, help the system operator to find problems in time, make adjustments, and prevent potential faults and accidents.

[0107] To adjust the power distribution equipment according to the power flow increment, in an optional embodiment, the power distribution equipment affected in the power distribution network is adjusted according to the power flow increment of the affected branch, and the first control unit comprises:

[0108] A first control module is configured to adjust the power distribution of the affected power equipment in the power distribution network when the power flow increment of the affected branch exceeds a predetermined threshold.

[0109] Specifically, when the power flow increment of the affected branch exceeds the predetermined threshold, the power distribution of the affected power equipment needs to be adjusted, and by adjusting the power distribution of the affected power equipment, the load of the affected branch can be reduced, the current can be reduced, the overload problem can be avoided, the operation state of the power system can be optimized, the reliability of the system can be improved, the risk of system failure can be reduced, and stable power supply of the power system can be ensured.

[0110] The power distribution network power flow calculation device comprises a processor and a memory, the first establishment unit, the second establishment unit, the first determination unit, the third establishment unit, the fourth establishment unit, the first calculation unit, the first control unit and the like are stored in the memory as program units, and the corresponding functions are realized by the processor executing the program units stored in the memory. The modules are located in the same processor; alternatively, the modules are located in different processors in any combination.

[0111] The processor comprises a core, and the core retrieves the corresponding program unit from the memory. The core can be one or more, and the power flow calculation efficiency can be improved by adjusting the core parameters.

[0112] The memory can comprise a non-permanent memory in a computer readable medium, a random access memory (RAM) and / or a non-volatile memory such as a read-only memory (ROM) or a flash memory (flash RAM), and the memory comprises at least one memory chip.

[0113] The embodiment of the application provides a computer readable storage medium, and the computer readable storage medium comprises a stored program, wherein the program controls the device where the computer readable storage medium is located to execute the power distribution network power flow calculation method when the program is running.

[0114] Specifically, a power distribution network power flow calculation method comprises:

[0115] Step S201, establishing a power distribution network power flow equation, the power distribution network power flow equation includes a public coupling node power flow equation, a load node power flow equation and a distributed power supply power flow equation, the public coupling node power flow equation is used to calculate the complex power of the public coupling node in the power distribution network, the load node power flow equation is used to calculate the complex power of the load node in the power distribution network, and the distributed power supply power flow equation is used to calculate the complex power of the distributed power supply in the power distribution network.

[0116] Step S202, in the case of disconnection of any node in the power distribution network, a first equation is established according to the voltage phase angle of each target branch, the reactance of each target branch and the initial power flow of each target branch, the target branch is an affected branch after the node is disconnected, the first equation is used to calculate the power flow increment of the affected branch, and the initial power flow is the power flow of the node or the target branch before the node is disconnected.

[0117] Step S203, the ratio of the power flow increment of the target branch to the initial power flow of the node is determined as the distribution factor of the target branch.

[0118] Step S204, the distribution factor vector is composed of the distribution factors of each target branch of the affected branch.

[0119] Step S205, a second equation is established according to the distribution factor vector and the active power flow vector of the affected branch when the power distribution network is in a steady state, and the second equation is used to calculate the power flow increment of the affected branch.

[0120] Step S206, the power flow increment of the affected branch is calculated by simultaneously solving the power distribution network power flow equation, the first equation and the second equation.

[0121] Step S207, according to the power flow increment of the affected branch, the power distribution of the affected power equipment in the power distribution network is adjusted.

[0122] An embodiment of the application provides a processor, which is used to run a program, wherein the processor is used to execute the power distribution network power flow calculation method when the program is run.

[0123] Specifically, a power distribution network power flow calculation method comprises:

[0124] Step S201, establishing a power distribution network power flow equation, the power distribution network power flow equation including a public coupling node power flow equation, a load node power flow equation and a distributed power supply power flow equation, the public coupling node power flow equation being used to calculate complex power of a public coupling node in the power distribution network, the load node power flow equation being used to calculate complex power of a load node in the power distribution network, and the distributed power supply power flow equation being used to calculate complex power of a distributed power supply in the power distribution network;

[0125] Step S202, in the case of disconnection of any node in the power distribution network, a first equation is established according to voltage phase angle of each target branch, reactance of each target branch and initial power flow of each target branch, the target branch being an affected branch after disconnection of the node, the first equation being used to calculate power flow increment of the affected branch, and the initial power flow being power flow of the node or the target branch before disconnection of the node;

[0126] Step S203, determining a distribution factor of the target branch as a ratio of the power flow increment of the target branch to the initial power flow of the node;

[0127] Step S204, forming a distribution factor vector by using each distribution factor of each target branch of the affected branch;

[0128] Step S205, establishing a second equation according to the distribution factor vector and active power flow vector of the affected branch when the power distribution network is in a steady state, the second equation being used to calculate the power flow increment of the affected branch;

[0129] Step S206, calculating the power flow increment of the affected branch by simultaneously solving the power distribution network power flow equation, the first equation and the second equation;

[0130] Step S207, adjusting power distribution of an affected power device in the power distribution network according to the power flow increment of the affected branch.

[0131] The application also provides a computer program product adapted to execute a program including at least the following steps when executed on a data processing device:

[0132] Step S201, establishing a power distribution network power flow equation, the power distribution network power flow equation including a public coupling node power flow equation, a load node power flow equation and a distributed power supply power flow equation, the public coupling node power flow equation being used to calculate complex power of a public coupling node in the power distribution network, the load node power flow equation being used to calculate complex power of a load node in the power distribution network, and the distributed power supply power flow equation being used to calculate complex power of a distributed power supply in the power distribution network;

[0133] Step S202, in the case of disconnection of any one node in the power distribution network, a first equation is established according to the voltage phase angle of each target branch, the reactance of each target branch and the initial load flow of each target branch, the target branch is an affected branch after the disconnection of the node, the first equation is used to calculate the load flow increment of the affected branch, and the initial load flow is the load flow of the node or the target branch before the disconnection of the node;

[0134] Step S203, a ratio of the load flow increment of the target branch to the initial load flow of the node is determined as a distribution factor of the target branch;

[0135] Step S204, distribution factor vectors are composed of the distribution factors of each target branch of the affected branch;

[0136] Step S205, a second equation is established according to the distribution factor vectors and the active power flow vector of the affected branch when the power distribution network is in a steady state, and the second equation is used to calculate the load flow increment of the affected branch;

[0137] Step S206, the load flow increment of the affected branch is calculated by simultaneously solving the power distribution network flow equation, the first equation and the second equation;

[0138] Step S207, the power distribution of the affected power equipment in the power distribution network is adjusted according to the load flow increment of the affected branch.

[0139] Embodiments of the present application also provide a power distribution network load flow calculation system, comprising one or more processors, a memory and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, including executing any one of the methods in the feeder group transfer capacity evaluation method.

[0140] Specifically, a power distribution network load flow calculation method comprises:

[0141] Step S201, a power distribution network load flow equation is established, the power distribution network load flow equation comprises a common coupling node load flow equation, a load node load flow equation and a distributed power supply load flow equation, the common coupling node load flow equation is used to calculate the complex power of the common coupling node in the power distribution network, the load node load flow equation is used to calculate the complex power of the load node in the power distribution network, and the distributed power supply load flow equation is used to calculate the complex power of the distributed power supply in the power distribution network;

[0142] Step S202, in the case of disconnecting any one node in the power distribution network, a first equation is established according to the voltage phase angle of each target branch, the reactance of each target branch and the initial power flow of each target branch, the target branch is the affected branch after the node is disconnected, the first equation is used to calculate the power flow increment of the affected branch, and the initial power flow is the power flow of the node or the target branch before the node is disconnected;

[0143] Step S203, a ratio of the power flow increment of the target branch and the initial power flow of the node is determined as a distribution factor of the target branch;

[0144] Step S204, a distribution factor vector is composed of the distribution factors of each target branch of the affected branch;

[0145] Step S205, a second equation is established according to the distribution factor vector and the active power flow vector of the affected branch when the power distribution network is in a steady state, and the second equation is used to calculate the power flow increment of the affected branch;

[0146] Step S206, the power flow increment of the affected branch is calculated by simultaneously solving the power flow equation of the power distribution network, the first equation and the second equation;

[0147] Step S207, the power distribution of the affected power equipment in the power distribution network is adjusted according to the power flow increment of the affected branch.

[0148] Obviously, those skilled in the art should understand that the modules or steps of the present application can be realized by general computing devices, which can be concentrated on a single computing device or distributed on a network composed of multiple computing devices, and they can be realized by program codes executable by computing devices, so that they can be stored in storage devices and executed by computing devices, and in some cases, the steps shown or described can be executed in different order, or they can be manufactured into individual integrated circuit modules, or multiple modules or steps can be manufactured into a single integrated circuit module. Therefore, the present application is not limited to any specific hardware and software combination.

[0149] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system or a computer program product. Therefore, the present application can be in the form of a complete hardware embodiment, a complete software embodiment or an embodiment combining software and hardware aspects. Moreover, the present application can be in the form of a computer program product implemented on one or more computer usable storage media containing computer usable program codes (including but not limited to disk storage, CD-ROM, optical storage, etc.).

[0150] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 means for functionally implementing the steps listed in the flowchart block or blocks.

[0151] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instructions which implement the function specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 means for functionally implementing the steps listed in the flowchart block or blocks.

[0152] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 means for functionally implementing the steps listed in the flowchart block or blocks.

[0153] In a typical configuration, a computing device includes one or more processors (CPUs), input / output interfaces, network interfaces, and memory.

[0154] The memory can include non-persistent memory and / or volatile memory, such as a random access memory (RAM) including a cache area for the temporary storage of data. The memory can also include non-volatile memory, such as read only memory (ROM), electrically programmable read only memory (EPROM), or electrically erasable programmable read only memory (EEPROM), for the storage of software that is read during runtime. The memory is an example of computer readable media.

[0155] Computer-readable media includes permanent and non-permanent, movable and non-movable media that can be implemented by any method or technology to store information. The information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassette, magnetic tape disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information accessible by a computing device. According to the definition herein, computer-readable media does not include transitory media such as modulated data signals and carriers.

[0156] It should also be noted that the terms "comprising", "including", or any other variant thereof are intended to cover non-exclusive inclusion, so that processes, methods, articles or devices including a series of elements not only include those elements, but also include other elements not explicitly listed, or inherent to such processes, methods, articles or devices. Without more limitations, the element defined by the statement "including a" does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0157] From the above description, it can be seen that the above-mentioned embodiments of the present application achieve the following technical effects:

[0158] 1) The power distribution network power flow calculation method of the application, the power distribution network power flow equation is established, the power distribution network power flow equation includes the public coupling node power flow equation, the load node power flow equation and the distributed power supply power flow equation, the public coupling node power flow equation is used for calculating the complex power of the public coupling node in the power distribution network, the load node power flow equation is used for calculating the complex power of the load node in the power distribution network, and the distributed power supply power flow equation is used for calculating the complex power of the distributed power supply in the power distribution network;In the case that any node in the power distribution network is disconnected, a first equation is established according to the voltage phase angle of each target branch, the reactance of each target branch and the initial power flow of each target branch, the target branch is the affected branch after the node is disconnected, the first equation is used to calculate the power flow increment of the affected branch, and the initial power flow is the power flow of the node or the target branch before the node is disconnected;The ratio of the power flow increment of the target branch to the initial power flow of the node is determined as the distribution factor of the target branch;The distribution factor vector is composed of the distribution factor of each target branch of the affected branch;The second equation is established according to the distribution factor vector and the active power flow vector of the affected branch when the power distribution network is in steady state, the second equation is used to calculate the power flow increment of the affected branch;The power flow increment of the affected branch is calculated by simultaneously solving the power distribution network power flow equation, the first equation and the second equation;According to the power flow increment of the affected branch, the power distribution of the affected power equipment in the power distribution network is adjusted. The application calculates the complex power of the public coupling node, the load node and the distributed power supply in the power distribution network by establishing the power distribution network power flow equation, calculates the power flow increment of the affected branch after the node is disconnected in the power distribution network by simultaneously solving the power distribution network power flow equation, the first equation and the second equation, and adjusts the power distribution of the affected power equipment in time according to the power flow increment, avoids the overload of the line and affects the normal operation of the power distribution network, and solves the problem that the affected power equipment cannot be adjusted in time due to the low efficiency of the power flow calculation in the prior art.

[0159] 2) The power distribution network power flow calculation device of the application, a first establishment unit is used to establish a power distribution network power flow equation, the power distribution network power flow equation includes a public coupling node power flow equation, a load node power flow equation and a distributed power supply power flow equation, the public coupling node power flow equation is used to calculate the complex power of the public coupling node in the power distribution network, the load node power flow equation is used to calculate the complex power of the load node in the power distribution network, and the distributed power supply power flow equation is used to calculate the complex power of the distributed power supply in the power distribution network;A second establishment unit is used to establish a first equation according to the voltage phase angle of each target branch, the reactance of each target branch and the initial power flow of each target branch in the case of disconnecting any node in the power distribution network, the target branch is the affected branch after the node is disconnected, the first equation is used to calculate the power flow increment of the affected branch, and the initial power flow is the power flow of the node or the target branch before the node is disconnected;A first determination unit is used to determine the ratio of the power flow increment of the target branch to the initial power flow of the node as the distribution factor of the target branch;A third establishment unit is used to form a distribution factor vector by the distribution factor of each target branch of the affected branch;A fourth establishment unit is used to establish a second equation according to the distribution factor vector and the active power flow vector of the affected branch when the power distribution network is in a steady state, the second equation is used to calculate the power flow increment of the affected branch;A first calculation unit is used to calculate the power flow increment of the affected branch by simultaneously solving the power distribution network power flow equation, the first equation and the second equation;A first control unit is used to adjust the power distribution of the affected power equipment in the power distribution network according to the power flow increment of the affected branch. The application calculates the complex power of the public coupling node, the load node and the distributed power supply in the power distribution network by establishing the power distribution network power flow equation, calculates the power flow increment of the affected branch after the node is disconnected in the power distribution network by simultaneously solving the power distribution network power flow equation, the first equation and the second equation, and adjusts the power distribution of the affected power equipment in time according to the power flow increment, avoids the overload of the line and affects the normal operation of the power distribution network, and solves the problem that the affected power equipment cannot be adjusted in time due to the low efficiency of the power flow calculation in the prior art.

[0160] The above only describes the preferred embodiments of the application and is not used to limit the application. The application can have various changes and changes for those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the application shall be included in the protection scope of the application.

Claims

1. A power distribution network power flow calculation method, characterized by, The method comprises the following steps: establishing power flow equations of a power distribution network, the power flow equations comprising common coupling node power flow equations, load node power flow equations and distributed power source power flow equations, the common coupling node power flow equations being used to calculate complex power of common coupling nodes in the power distribution network, the load node power flow equations being used to calculate complex power of load nodes in the power distribution network, and the distributed power source power flow equations being used to calculate complex power of distributed power sources in the power distribution network; in the case of disconnection of any node in the power distribution network, establishing a first equation according to voltage phase angles of target branches, reactances of the target branches and initial power flow amounts of the target branches, the target branches being affected branches after disconnection of the node, the first equation being used to calculate power flow increments of the affected branches, and the initial power flow amount being a power flow amount of the node or the target branch before disconnection of the node; determining distribution factors of the target branches as ratios of the power flow increments of the target branches to the initial power flow amount of the node; composing a distribution factor vector by using the distribution factors of the target branches of the affected branches; establishing a second equation according to the distribution factor vector and an active power flow vector of the affected branches when the power distribution network is in a steady state, the second equation being used to calculate the power flow increments of the affected branches; calculating the power flow increments of the affected branches by simultaneously solving the power flow equations of the power distribution network, the first equation and the second equation; adjusting power distribution of affected power equipment in the power distribution network according to the power flow increments of the affected branches.

2. The method of claim 1, wherein, The method comprises the following steps: Establishing a public coupling node power flow equation where N is the total number of nodes in the distribution network, Y ik is the admittance of the branch between node i and node k, is the voltage vector of node k, is the voltage vector of node i, is the complex power of node i, is the complex power generated by the generator of node i, is the complex power consumed by the load of node i, is the voltage vector of node r, G is a set of common coupling nodes in the power distribution network; establishing a load node power flow equation where Y lk is an admittance of a branch of node l and node k, is a voltage vector of node l, is a known injected real power of load node l, is a known injected reactive power of load node l, P Ll is a real power consumed by load node l, Q Ll is a reactive power consumed by load node k, is a complex power generated by a generator of node l, is a complex power consumed by a load of node l, L is a set of load nodes in the power distribution network; Establishing distributed power flow equations where Y mk is the admittance of the branch between node m and node k, is the voltage vector of node m, is the complex power generated by the generators of node m, is the complex power consumed by the loads of node m, is the known injected real power of node m, is the known injected reactive power of node m.

3. The method of claim 1, wherein, establishing power flow equations of a power distribution network, the power flow equations comprising common coupling node power flow equations, load node power flow equations and distributed power source power flow equations, including: establishing first equations according to voltage phase angles of each of the target branches, reactances of each of the target branches, and initial power flow of each of the target branches wherein m is the total number of the affected branches, P is the power flow of branch k after the node l is disconnected, k θ is the initial power flow of branch k, k φ is the voltage phase angle of branch k, k x is the reactance of branch k, and ΔP is the power flow increment of the affected branches.

4. The method of claim 1, wherein, in the case of disconnection of any node in the power distribution network, establishing a first equation according to voltage phase angles of target branches, reactances of the target branches and initial power flow amounts of the target branches, including: determining the distribution factor where ΔP k is the power flow increment of branch k after node l is disconnected, P l is the initial tidal flow for node i.

5. The method of claim 1, wherein, determining distribution factors of the target branches as ratios of the power flow increments of the target branches to the initial power flow amount of the node, including: In the case that the node is disconnected, a susceptance matrix of the power distribution network is calculated, the susceptance matrix being where B0 is a susceptance matrix of the power distribution network before the node is disconnected, A Δ is a connection matrix composed of connection vectors of the affected branches, is a branch susceptance variation matrix of a branch where the node is located before the node is disconnected. calculating, according to the susceptance matrix of the power distribution network, an active power flow column vector P of the affected branch when the power distribution network is in a steady state ml = B'θ, wherein θ is a voltage phase angle vector of the node; establishing a second equation ΔP k = D k P ml where D k is the distribution factor vector and P ml is the active power flow vector of the affected branches when the power distribution network is in steady state.

6. The method of claim 1, wherein, establishing a second equation according to the distribution factor vector and an active power flow vector of the affected branches when the power distribution network is in a steady state, including: adjusting power distribution of affected power equipment in the power distribution network according to the power flow increments of the affected branches, including:

7. A power distribution network power flow calculation apparatus characterized by comprising: in the case that the power flow increment of the affected branch exceeds a predetermined threshold, adjusting power distribution of the affected power equipment in the power distribution network. The method comprises the following steps: a first establishing unit is configured to establish power flow equations of a power distribution network, the power flow equations comprising common coupling node power flow equations, load node power flow equations and distributed power source power flow equations, the common coupling node power flow equations being used to calculate complex power of common coupling nodes in the power distribution network, the load node power flow equations being used to calculate complex power of load nodes in the power distribution network, and the distributed power source power flow equations being used to calculate complex power of distributed power sources in the power distribution network; The second establishing unit is configured to, in the case that any node in the power distribution network is disconnected, establish a first equation according to voltage phase angles of each target branch, reactance of each target branch, and initial power flow of each target branch, the target branch being an affected branch after the node is disconnected, the first equation being used to calculate a power flow increment of the affected branch, and the initial power flow being a power flow of the node or the target branch before the node is disconnected. The first determining unit is configured to determine a ratio of the power flow increment of the target branch to the initial power flow of the node as a distribution factor of the target branch. The third establishing unit is configured to form a distribution factor vector by using the distribution factors of each target branch of the affected branch. The fourth establishing unit is configured to establish a second equation according to the distribution factor vector and an active power flow vector of the affected branch when the power distribution network is in a steady state, the second equation being used to calculate the power flow increment of the affected branch. The first calculating unit is configured to calculate the power flow increment of the affected branch by simultaneously solving the power flow equation of the power distribution network, the first equation, and the second equation. The first control unit is configured to adjust power distribution of an affected power device in the power distribution network according to the power flow increment of the affected branch.

8. A computer-readable storage medium, characterized in that, The computer readable storage medium comprises a stored program, wherein the computer readable storage medium controls a device where the computer readable storage medium is located to execute the method of any one of claims 1 to 6 when the program is executed.

9. A computer program product comprising a computer program, characterized in that, The computer program is executed by a processor to implement the method of any one of claims 1 to 6.

10. A power distribution network power flow calculation system, characterized by, The computer program is executed by a processor to implement the method of any one of claims 1 to 6. The computer program is executed by a processor to implement the method of any one of claims 1 to 6. The computer program is executed by a processor to implement the method of any one of claims 1 to 6. The computer program is executed by a processor to implement the method of any one of claims 1 to 6. The computer program is executed by a processor to implement the method of any one of claims 1 to 6. The computer program is executed by a processor to implement the method of any one of claims 1 to 6.

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