Power flow convergence adjustment method under power system maintenance mode

Abstract

The present invention discloses a method for adjusting the convergence of power flow in a power system maintenance mode, which is used to solve the problem that when the required calculation scenario actually has no solution, it is impossible to give a reasonable convergence result through adjustment. The network topology data of the power grid is obtained and the outage branch is determined; based on the network topology data, the first and second admittance matrices before the branch is out of service and the third admittance matrix after the outage are constructed; according to the first admittance matrix, the node with the smallest distance and multiple nodes with the largest distance are solved; the power impact is sorted in combination with the second admittance matrix and the node with the smallest distance to obtain multiple positive / negative impact nodes; the reactive compensation nodes are sorted in combination with the third admittance matrix, the node with the smallest distance and each node with the largest distance to obtain multiple reactive compensation nodes; the reactive compensation capacity of each reactive compensation node is increased, and the power flow calculation is re-performed. When the power flow does not converge, the active output reduction / increase adjustment is performed on multiple positive / negative impact nodes based on the preset power target value to obtain the adjustment result.

Description

Technical Field

[0001] The present invention relates to the technical field of power system stability analysis, and in particular to a method for adjusting power flow convergence in a power system maintenance mode, a device for adjusting power flow convergence in a power system maintenance mode, an electronic device, and a storage medium. Background Art

[0002] Power flow calculations are fundamental to power grid planning and operational analysis. Their goal is to determine the steady-state operating state of the power system. If the power flow calculations do not converge, critical parameters such as voltage, current, and power distribution cannot be accurately determined. This can lead to the inability to detect potential overloads or voltage instability, threatening the safe and stable operation of the power grid. Furthermore, making power grid planning or scheduling decisions based on non-convergent power flow calculation results can lead to erroneous conclusions, causing equipment damage or other serious consequences. Furthermore, in real-time operations, the results of power flow calculations can serve as a reference for monitoring power grid status. Failure to achieve convergence can delay fault diagnosis or lead to operational errors.

[0003] Currently, most power system stability analyses use converged power flow conditions as input. To address the non-convergence of power flow calculations, which often arise when arranging grid operation modes, two main mainstream technologies for improving power flow convergence exist. One is the expert experience-based adjustment method. Specifically, by assuming that certain nodes can provide unlimited reactive power compensation, the required reactive power compensation for each node is calculated and the required value is approximated as closely as possible from nearby nodes that actually provide reactive power compensation. The other is a data-driven configuration method. Specifically, scenarios close to the current calculation method are identified from massive amounts of historically converged data. Reactive power compensation values ​​from these historical data are then extracted to improve the convergence of the current calculation method.

[0004] However, when using these two methods, if the scenario being calculated actually has no solution, the adjustment will only result in a conclusion of failure, without being able to provide a reasonable convergence result. This problem is particularly prominent in the maintenance calculation scenario in power system analysis. Summary of the Invention

[0005] The present invention provides a method for adjusting the convergence of a power flow in a power system maintenance mode, a device for adjusting the convergence of a power flow in a power system maintenance mode, an electronic device and a storage medium, which are used to solve or partially solve the technical problem that, in a power system maintenance mode, when the scenario to be calculated actually has no solution, the current technology cannot provide a reasonable convergence result through adjustment.

[0006] The present invention provides a method for adjusting power flow convergence in a power system maintenance mode, comprising:

[0007] Obtain network topology data of the power grid and determine at least one outage branch line that needs to be shut down for maintenance;

[0008] For each of the outage branches, based on the network topology data, constructing a first admittance matrix and a second admittance matrix of the complete network before the outage branch is shut down, and a third admittance matrix after the outage branch is shut down;

[0009] Solve the minimum distance node of the outage branch with the minimum electrical distance according to the first admittance matrix, and simultaneously screen out a preset number of maximum electrical distance nodes;

[0010] sorting node power impacts by combining the second admittance matrix and the node with the minimum distance to obtain a plurality of positively impacted nodes and a plurality of negatively impacted nodes;

[0011] sorting nodes by reactive compensation capability based on the third admittance matrix, the node with the smallest distance, and each node with the largest electrical distance, to obtain a plurality of reactive compensation nodes;

[0012] Improve the reactive compensation capacity of each of the reactive compensation nodes and recalculate the flow. When the flow calculation result indicates that the flow does not converge, based on the preset power target value, adjust the active output of the multiple positively impacted nodes to reduce the active output, and at the same time adjust the active output of the multiple negatively impacted nodes to increase the active output, so as to obtain the flow convergence adjustment result.

[0013] Optionally, the network topology data includes N nodes and M branches of the power grid; and constructing a first admittance matrix and a second admittance matrix of the complete network before shutting down the shut-down branch, and a third admittance matrix after shutting down the shut-down branch based on the network topology data includes:

[0014] Based on the N nodes, construct an N-dimensional complex matrix with an initial value of 0 ;

[0015] Traverse the N nodes, when the node There is a branch to ground, and the equivalent impedance of the branch to ground is season The number of Increase ,get ;

[0016] Traverse the M branches and define the nodes With node The equivalent impedance between ;

[0017] Separate orders The number of and Increase , number of Increase , number of Increase , obtain the first admittance matrix of the complete network before shutting down the shut-down branch ;

[0018] Respectively The number of 、 、 Set the real part of ;

[0019] Separate orders The number of and Increase , number of Increase , number of Increase , obtain the second admittance matrix of the complete network before shutting down the shut-down branch ;

[0020] Traverse the M branches except the outage branch and define the node With node The equivalent impedance between ,get ;

[0021] Respectively The number of 、 、 The real part of is set to 0, and we get ;

[0022] Separate orders The number of and Increase , number of Increase , number of Increase , obtain the third admittance matrix of the complete network after shutting down the outage branch .

[0023] Optionally, the out-of-service branch is the m-th branch among the M branches, and the nodes connected to the m-th branch are node s and node t respectively; solving the minimum distance node with the minimum electrical distance of the out-of-service branch according to the first admittance matrix, and simultaneously screening out a preset number of nodes with maximum electrical distances, includes:

[0024] Set N-dimensional vector , The sth element in is 1.0, and the rest are 0;

[0025] Set N-dimensional vector ;

[0026] Based on the first admittance matrix , by solving Obtain the The value of Filter out the node whose absolute value is greater than 0 and whose numerical value corresponds to the smallest serial number from all the values ​​as the minimum distance node with the smallest electrical distance to the outage branch;

[0027] Regarding the All values ​​of are sorted from large to small according to absolute value, and nodes corresponding to a preset number of serial numbers are selected from them in descending order as nodes with the largest electrical distance.

[0028] Optionally, the N nodes include S generator nodes; and the node power impact sorting performed in combination with the second admittance matrix and the node with the minimum distance to obtain a plurality of positively impacted nodes and a plurality of negatively impacted nodes includes:

[0029] Traverse the S generator nodes and set the N-dimensional vector , The cth element in is 1.0, the rth element corresponding to the node with the smallest distance is -1.0, and the rest are 0;

[0030] Set N-dimensional vector ;

[0031] Based on the second admittance matrix , by solving Obtain the The numerical value of

[0032] Let node power affect ,in, 、 They are The sth and tth elements of is the reactance of the outage branch;

[0033] Calculate the total number of generator nodes value, and all the generator nodes The value is divided into multiple positive Values ​​and multiple negative value;

[0034] According to the stated The value is sorted from large to small for all The generator nodes with positive values ​​are sorted to obtain the positive impact nodes that are sorted from large to small in terms of the positive impact on node power when the outage branch is shut down;

[0035] According to the negative The absolute value of the value is in descending order for all The generator nodes with negative values ​​are sorted, and the negative impact nodes caused by the negative impact on node power when the outage branch is shut down are obtained and sorted from large to small.

[0036] Optionally, the step of sorting nodes with reactive compensation capabilities by combining the third admittance matrix, the node with the smallest distance, and each node with the largest electrical distance to obtain a plurality of reactive compensation nodes includes:

[0037] Traverse each of the nodes with the largest electrical distance and set the N-dimensional vector , The cth element in is 1.0, the rth element corresponding to the node with the smallest distance is -1.0, and the rest are 0;

[0038] Set N-dimensional vector ;

[0039] Based on the third admittance matrix , by solving Obtain the The numerical value of

[0040] For each node c, compare the node c in the With the , and select the preset E nodes with the largest deviation values ​​from them;

[0041] The E nodes in each group selected are combined, and all nodes with reactive compensation capability obtained after the combination are sorted in descending order according to the deviation value, so as to obtain reactive compensation nodes whose voltage changes before and after the outage are sorted in descending order.

[0042] Optionally, the increasing the reactive compensation capacity of each reactive compensation node includes:

[0043] For each reactive power compensation node, when one or more groups of reactors have been previously put into use at the reactive power compensation node, reducing one of the groups of reactors;

[0044] When the reactive power compensation node has not previously been put into operation with a reactor, a group of capacitors is put into operation.

[0045] Optionally, the adjusting the active output of the plurality of positively impacting nodes to decrease based on the preset power target value and adjusting the active output of the plurality of negatively impacting nodes to increase based on the preset power target value includes:

[0046] For a first positive influence node ranked first among the multiple positive influence nodes, when it is determined that a first current output of the first positive influence node is greater than or equal to a preset power target value, directly subtracting the preset power target value from the first current output to complete the active output reduction adjustment;

[0047] When it is determined that the first current output of the first positively influential node is less than the preset power target value, the output of the first positively influential node is set to 0, and the difference between the first current output and the preset power target value is adjusted by the positively influential nodes other than the first positively influential node in accordance with the active output reduction adjustment method of the first positively influential node;

[0048] For a first negatively impacting node ranked first among the multiple negatively impacting nodes, when it is determined that the difference between the maximum output of the first negatively impacting node and the second current output is greater than or equal to a preset power target value, directly increasing the preset power target value based on the second current output to complete the active output increase adjustment;

[0049] When it is determined that the difference between the maximum output of the first negatively impacted node and the second current output is less than the preset power target value, the output of the first negatively impacted node is adjusted to the maximum output, and the difference between the preset power target value and the maximum output is adjusted according to the active output increase adjustment method of the first negatively impacted node, and the negatively impacted nodes other than the first negatively impacted node perform subsequent active output increase adjustments.

[0050] Optionally, the method further includes:

[0051] After the active power output adjustment is completed, the power flow calculation is re-performed based on the power flow convergence adjustment result;

[0052] When the current power flow calculation result indicates that the power flow has converged, the adjustment is ended, and the power flow convergence adjustment result is used as the final operation mode.

[0053] Optionally, the method further includes:

[0054] When the current power flow calculation result indicates that the power flow is not converged and the current adjustment cycle number has not reached the preset upper limit, the power flow convergence adjustment result is used as the current operation mode, and the process is re-jumped to the reactive compensation capacity execution step of the reactive compensation node;

[0055] When the current power flow calculation result indicates that the power flow does not converge, and the current adjustment cycle number reaches a preset upper limit, the adjustment is stopped and an adjustment failure result is output.

[0056] The present invention also provides a power flow convergence adjustment device in a power system maintenance mode, comprising:

[0057] A data acquisition unit, configured to acquire network topology data of the power grid and determine at least one outage branch line that needs to be shut down for maintenance;

[0058] An admittance matrix construction unit is configured to construct, for each of the outage branches, a first admittance matrix and a second admittance matrix of the complete network before the outage branch is shut down, and a third admittance matrix after the outage branch is shut down, based on the network topology data;

[0059] an electrical distance node solving unit, configured to solve the minimum distance node having the minimum electrical distance to the outage branch according to the first admittance matrix, and simultaneously screen out a preset number of maximum electrical distance nodes;

[0060] a node power impact ranking unit, configured to perform node power impact ranking based on the second admittance matrix and the node with the smallest distance, to obtain a plurality of positively impacted nodes and a plurality of negatively impacted nodes;

[0061] a reactive compensation capability node sorting unit, configured to sort the reactive compensation capability nodes by combining the third admittance matrix, the minimum distance node, and each of the maximum electrical distance nodes to obtain a plurality of reactive compensation nodes;

[0062] The active power output adjustment unit is used to increase the reactive compensation capacity of each reactive compensation node and recalculate the power flow. When the power flow calculation result indicates that the power flow does not converge, based on the preset power target value, the active power output of the multiple positive impact nodes is reduced, and the active power output of the multiple negative impact nodes is increased to obtain the power flow convergence adjustment result.

[0063] The present invention further provides an electronic device, comprising a processor and a memory:

[0064] The memory is used to store program code and transmit the program code to the processor;

[0065] The processor is configured to execute the power flow convergence adjustment method in the power system maintenance mode as described in any one of the above items according to the instructions in the program code.

[0066] The present invention also provides a computer-readable storage medium, which is used to store program code, and the program code is used to execute the power flow convergence adjustment method in the power system maintenance mode as described in any one of the above items.

[0067] It can be seen from the above technical solutions that the present invention has the following advantages:

[0068] A method for adjusting power flow convergence in a power system maintenance mode is provided. The method includes obtaining network topology data of the power grid and determining at least one outage branch that needs to be shut down during maintenance. For each outage branch, based on the network topology data, a first admittance matrix and a second admittance matrix are constructed for the complete network before the outage of the branch that needs to be shut down, and a third admittance matrix is ​​constructed after the outage of the branch that needs to be shut down. The node with the smallest electrical distance to the outage branch is solved based on the first admittance matrix, and a preset number of nodes with the largest electrical distance are screened out. The node power impact is sorted based on the second admittance matrix and the nodes with the smallest distance to obtain multiple positive impact nodes and multiple negative impact nodes. The method also includes sorting the nodes with the highest reactive compensation capacity based on the third admittance matrix, the nodes with the smallest distance, and the nodes with the largest electrical distance to obtain multiple reactive compensation nodes. The reactive compensation capacity of each reactive compensation node is increased, and the power flow calculation is re-performed. When the power flow calculation result indicates that the power flow is not converged, the active output of multiple positive impact nodes is adjusted to be reduced, and the active output of multiple negative impact nodes is adjusted to be increased based on a preset power target value, thereby obtaining a power flow convergence adjustment result. On the one hand, by identifying key units that affect outages, the reactive voltage levels on transmission channels are alternately increased, and the transmission power shifts caused by outages are reduced. This allows for a combined reactive and active power adjustment. While minimizing active power fluctuations and avoiding large-scale changes, a convergence method is developed, improving the convergence of power flow calculations under maintenance. On the other hand, given that the original active power distribution scenario is virtually unsolvable, a reasonable convergence method is developed through active power output adjustments whenever possible, thereby improving the convergence of power flow calculations under maintenance, providing a basis for further grid analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0070] Figure 1 A flowchart of the steps of a power flow convergence adjustment method in a power system maintenance mode;

[0071] Figure 2 It is a schematic diagram of equivalent impedance of branches between nodes;

[0072] Figure 3 The structure block diagram of a power flow convergence adjustment device in a power system maintenance mode. DETAILED DESCRIPTION

[0073] Embodiments of the present invention provide a method for adjusting the convergence of a power flow in a power system maintenance mode, a device for adjusting the convergence of a power flow in a power system maintenance mode, an electronic device, and a storage medium, which are used to solve or partially solve the technical problem that, in a power system maintenance mode, when the scenario to be calculated actually has no solution, the current technology cannot provide a reasonable convergence result through adjustment.

[0074] In order to make the purpose, features, and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0075] As an example, most current power system stability analyses use converged power flow conditions as input. To address the non-convergence of power flow calculations, which often arise when arranging grid operation modes, two main mainstream technologies are currently used to improve power flow convergence. One is the expert experience adjustment method. Specifically, by assuming that certain nodes can provide unlimited reactive power compensation, the required reactive power compensation for that node is calculated and the required value is approximated as closely as possible from nearby nodes that actually provide reactive power compensation. The other is a data-driven configuration method. Specifically, scenarios close to the current calculation method are searched for from massive amounts of historical convergence data, and reactive power compensation values ​​from the historical data are extracted to improve the convergence of the current calculation method.

[0076] However, when the above two methods are used, if the scenario to be calculated actually has no solution, only the conclusion that the adjustment has failed can be obtained, and a reasonable convergence result cannot be given through adjustment.

[0077] Further analysis by the present inventors reveals that the root cause of this problem lies in the fact that current methods for improving the convergence of power flow calculations assume that non-convergence is caused by inappropriate reactive power compensation, while ignoring the underlying cause of inappropriate active power distribution. This is particularly true when the power grid is incomplete, such as when certain key transmission channels are undergoing maintenance (as in the maintenance calculation scenario used in power system analysis). The correct approach is to significantly reduce the active power transmitted across the section, rather than simply configuring reactive power compensation.

[0078] Therefore, one of the core invention points of the embodiment of the present invention is: for the special scenario of maintenance mode calculation in power system analysis, a method for adjusting the power flow convergence under the maintenance mode of the power system is proposed. On the one hand, by finding the key units that affect the outage line, the reactive voltage level on the transmission channel and the transmission power transfer caused by the outage line are increased in turn, and the reactive and active adjustments are combined. A convergence method is given while keeping the active power changes as small as possible and avoiding large-scale changes, thereby improving the convergence of the power flow calculation under the maintenance mode. On the other hand, under the premise that the original active power distribution scenario is actually unsolvable, a reasonable convergence method is given by adjusting the active power output as much as possible, thereby improving the convergence of the power flow calculation under the maintenance mode, and providing a basis for other power grid analyses in the next step.

[0079] Reference Figure 1 , shows a flowchart of a method for adjusting power flow convergence in a power system maintenance mode provided by an embodiment of the present invention, which may specifically include the following steps:

[0080] Step 101: Acquire network topology data of the power grid and determine at least one outage branch line that needs to be shut down for maintenance;

[0081] First, obtain the network topology data for the power grid. This data primarily includes a currently available convergent power grid operation mode, N nodes, and M branches. The N nodes include S generators (corresponding to S generator nodes) and K nodes with reactive power compensation equipment. For example, consider the case of shutting down a branch for maintenance. Assume that the mth branch of the M branches requires maintenance. If this is not done directly, the power flow calculation will not converge. Also, assume that the nodes connected to the mth branch are nodes s and t.

[0082] Step 102: for each of the outage branches, constructing a first admittance matrix and a second admittance matrix of the complete network before the outage branch is shut down, and a third admittance matrix after the outage branch is shut down based on the network topology data;

[0083] In some embodiments, based on the network topology data, a first admittance matrix and a second admittance matrix of the complete network before the branch is shut down, and a third admittance matrix after the branch is shut down can be constructed as follows:

[0084] First, based on N nodes, construct an N-dimensional complex matrix with an initial value of 0 .

[0085] Then traverse N nodes, when the node There is a branch to ground (such as load, parallel capacitive reactance, generator, etc., or DC equivalent branch to ground, etc.), and the equivalent impedance of the branch to ground is season The number of Increase ,get .

[0086] Traverse M branches and define nodes With node The equivalent impedance between .node With node The equivalent impedance of the branch between Figure 2 shown.

[0087] Separate orders The number of and Increase , number of Increase , number of Increase , obtain the first admittance matrix of the complete network before the outage that requires the outage of the branch .

[0088] Respectively The number of 、 、 The real part of is set to 0, and we get .

[0089] Separate orders The number of and Increase , number of Increase , number of Increase , obtain the second admittance matrix of the complete network before the outage that requires the outage of the branch .

[0090] Traverse the M branches except the out-of-service branches and define the nodes With node The equivalent impedance between ,get .

[0091] Respectively The number of 、 、 The real part of is set to 0, and we get .

[0092] Separate orders The number of and Increase , number of Increase , number of Increase , obtain the third admittance matrix of the complete network after the outage requires the outage of the branch .

[0093] From the previous steps, we can see that the third admittance matrix The calculation process and the second admittance matrix Basically the same, the only difference is that when traversing the branch, the third admittance matrix Ignore the lines that need to be shut down. The third admittance matrix It can be understood as the second admittance matrix calculated after the line is shut down for maintenance. .

[0094] Step 103: Calculate the minimum distance node with the minimum electrical distance of the outage branch according to the first admittance matrix, and simultaneously select a preset number of maximum electrical distance nodes;

[0095] Based on the above, it can be seen that the out-of-service branch is the mth branch among M branches, and the nodes connected to the mth branch are nodes s and t. In some embodiments, the minimum distance node with the minimum electrical distance of the out-of-service branch is solved based on the first admittance matrix, and a preset number of nodes with the maximum electrical distance are screened out, which can be:

[0096] First set the N-dimensional vector , The sth element in is 1.0, and the rest are 0.

[0097] Then set the N-dimensional vector .

[0098] Based on the first admittance matrix , by solving get The value of All values ​​of 、 ... The node corresponding to the node with the smallest sequence number (denoted as the rth) and an absolute value greater than 0 is selected as the node with the smallest electrical distance to the outage branch.

[0099] right All values ​​of 、 ... Sort by absolute value from large to small, and select a preset number (which can be recorded as T, and the value is set according to actual conditions) of nodes corresponding to the serial numbers (i.e., the first T nodes) from large to small as the nodes with the largest electrical distance.

[0100] Step 104: sorting node power impacts by combining the second admittance matrix and the node with the minimum distance to obtain a plurality of positively impacted nodes and a plurality of negatively impacted nodes;

[0101] In conjunction with the above content, N nodes include S generator nodes. In some embodiments, the second admittance matrix and the node with the smallest distance are combined to perform node power impact sorting to obtain multiple positive impact nodes and multiple negative impact nodes, which can be:

[0102] First, traverse the S generator nodes and set the N-dimensional vector , The cth element in the matrix is ​​1.0, the rth element corresponding to the node with the smallest distance is -1.0, and the rest are 0.

[0103] Then set the N-dimensional vector .

[0104] Then based on the second admittance matrix , by solving get The numerical value of .

[0105] Let node power affect .in, 、 They are The sth and tth elements of is the reactance of the outage branch.

[0106] Calculate the total number of generator nodes value, and set the The value is divided into multiple positive and negative values ​​according to the positive and negative values. Values ​​and multiple negative value.

[0107] According to the positive The value is sorted from large to small for all The generator nodes with positive values ​​are sorted to obtain the positive impact nodes that bring positive impact on node power when the outage requires the shutdown of the branch. The positive impact nodes can be recorded as nodes ,node …….

[0108] According to negative The absolute value of the value is in descending order for all Sort the generator nodes with negative values ​​and get the nodes with negative impact on node power when the outage requires the shutdown of the branch. The negative impact nodes can be recorded as nodes ,node …….

[0109] In this step, a generator selection method for generator output transfer is given to achieve unit adjustment for specific objects during subsequent active output adjustment, thereby reducing the current overload situation under the active power flow transfer and maintenance reduction mode and improving the current convergence.

[0110] Step 105 , sorting nodes based on reactive compensation capabilities by combining the third admittance matrix, the node with the smallest distance, and each node with the largest electrical distance, to obtain a plurality of reactive compensation nodes;

[0111] In some embodiments, the reactive compensation capability nodes are sorted by combining the third admittance matrix, the node with the smallest distance, and the nodes with the largest electrical distances to obtain multiple reactive compensation nodes, which may be:

[0112] First, traverse each node with the largest electrical distance and set the N-dimensional vector , The cth element in the matrix is ​​1.0, the rth element corresponding to the node with the smallest distance is -1.0, and the rest are 0.

[0113] Then set the N-dimensional vector .

[0114] Then based on the third admittance matrix , by solving get The numerical value of

[0115] For each node c, compare node c in and The values ​​in are used to select the preset E nodes with the largest deviation values ​​(E can be set according to actual conditions).

[0116] Take the union of each group of E nodes selected, and sort all the nodes with reactive compensation capability obtained after taking the union from large to small according to the deviation value, and obtain the reactive compensation nodes whose voltage changes before and after the outage are sorted from large to small. The reactive compensation nodes obtained after sorting can be recorded as nodes 、 …….

[0117] In this step, a node selection method that improves voltage support strength is given, so that in the subsequent process, the reactive compensation capacity of the selected nodes can be increased to increase the voltage level of the nodes that are more affected by the power flow transfer, thereby improving the power flow convergence.

[0118] Step 106: Increase the reactive compensation capacity of each reactive compensation node and recalculate the flow. When the flow calculation result indicates that the flow does not converge, based on the preset power target value, adjust the active output of the multiple positively impacted nodes to reduce the active output, and at the same time adjust the active output of the multiple negatively impacted nodes to increase the active output, so as to obtain the flow convergence adjustment result.

[0119] Furthermore, the reactive compensation capacity of each reactive compensation node can be improved by: for each reactive compensation node (i.e. node 、 ...), increasing its reactive power compensation by one level. Specifically, if one or more reactors were previously connected at the reactive power compensation node, one of these reactors is removed. If no reactors were previously connected at the reactive power compensation node, a capacitor is connected.

[0120] After increasing the reactive compensation capacity of each reactive compensation node, recalculate the power flow. When the power flow calculation result indicates that the power flow has converged, the adjustment is completed. This result is the final converged operation mode.

[0121] When the power flow calculation results indicate that the power flow is not converged, the active output of multiple positively impacted nodes can be adjusted to be reduced based on the preset power target value, while the active output of multiple negatively impacted nodes can be adjusted to be increased.

[0122] Furthermore, the active power output reduction adjustment measures are as follows:

[0123] For multiple positive impact nodes (node ,node ...) , when judging the first positive impact node The first current output Greater than or equal to the preset power target value (i.e. the power target value to be reduced is selected in advance), the first current output is directly used Subtract the preset power target value , complete the active output reduction adjustment.

[0124] When judging the first positive impact node The first current output Less than the preset power target value When the first positive impact node The output is set to 0, the first current output and the preset power target value The difference between , according to the first positive impact node The active output reduction adjustment method is to reduce the number of nodes except the first positive impact node. Positive impact nodes other than ,node ...) Execute subsequent active power output reduction adjustments.

[0125] The specific adjustment measures for increasing active power output are as follows:

[0126] For multiple negatively impacting nodes (nodes ,node ...) , when judging the first negative impact node Maximum output With the second current output The difference is greater than or equal to the preset power target value When the second current output Add the preset power target value based on , complete the active output increase adjustment.

[0127] When judging the first negative impact node Maximum output With the second current output The difference is less than the preset power target value When the first negatively impacted node Adjust the output to the maximum output , the difference between the preset power target value and the maximum output , according to the first negative impact node The active output increase adjustment method is to remove the first negatively impacting node Negative impact nodes other than ,node ...) to carry out subsequent active power output increase adjustments.

[0128] After the active power output adjustment is completed, the power flow calculation is re-performed based on the power flow convergence adjustment results.

[0129] If the current power flow calculation result indicates that the power flow has converged, the adjustment is terminated and the power flow convergence adjustment result is used as the final operation mode.

[0130] If the current power flow calculation results indicate non-convergence and the current number of adjustment cycles has not reached the preset upper limit, the power flow convergence adjustment result will be used as the current operation mode, and the process will be redirected to the reactive compensation capacity execution step of the reactive compensation node. This allows for convergence while minimizing active power fluctuations by alternating adjustments to active power distribution and reactive voltage levels.

[0131] If the current power flow calculation result indicates that the power flow has not converged and the current adjustment cycle number reaches the preset upper limit, the adjustment is stopped and an adjustment failure result is output.

[0132] In another alternative, when two or more branches are shut down simultaneously, a sequential calculation approach can be employed. Specifically, the calculation for multiple branches to be shut down can be broken down into sequential shutdowns. For example, the power flow convergence adjustment described above can be performed on the first branch to be shut down, followed by the second branch, and so on, until the final branch to be shut down has been completed.

[0133] In an embodiment of the present invention, a method for adjusting the convergence of power flow in the maintenance mode of a power system is proposed for the special scenario of maintenance mode calculation in power system analysis. On the one hand, by finding the key units that affect the outage line, the reactive voltage level on the transmission channel and the transmission power transfer caused by the outage line are increased in turn, so as to realize the combination of reactive and active adjustment, and give a convergence method while keeping the active power change as small as possible and avoiding large-scale changes, thereby improving the convergence of power flow calculation in the maintenance mode. On the other hand, under the premise that the original active power distribution scenario is actually unsolvable, a reasonable convergence method is given by adjusting the active power output as much as possible, thereby improving the convergence of power flow calculation in the maintenance mode and providing a basis for other power grid analysis in the next step.

[0134] Reference Figure 3 , shows a structural block diagram of a power flow convergence adjustment device in a power system maintenance mode provided by an embodiment of the present invention, which may specifically include:

[0135] The data acquisition unit 301 is used to acquire network topology data of the power grid and determine at least one outage branch that needs to be shut down for maintenance;

[0136] An admittance matrix construction unit 302 is configured to construct, for each of the outage branches, a first admittance matrix and a second admittance matrix of the complete network before the outage branch is shut down, and a third admittance matrix after the outage branch is shut down, based on the network topology data;

[0137] An electrical distance node solving unit 303 is configured to solve the minimum distance node of the outage branch with the minimum electrical distance according to the first admittance matrix, and simultaneously select a preset number of maximum electrical distance nodes;

[0138] A node power impact ranking unit 304 is configured to perform node power impact ranking based on the second admittance matrix and the node with the smallest distance, to obtain a plurality of positively impacted nodes and a plurality of negatively impacted nodes;

[0139] A reactive compensation capability node sorting unit 305 is configured to sort the reactive compensation capability nodes based on the third admittance matrix, the minimum distance node, and each of the maximum electrical distance nodes to obtain a plurality of reactive compensation nodes;

[0140] The active output adjustment unit 306 is used to increase the reactive compensation capacity of each reactive compensation node and recalculate the flow. When the flow calculation result indicates that the flow does not converge, based on the preset power target value, the active output of the multiple positively impacting nodes is adjusted to decrease, and the active output of the multiple negatively impacting nodes is adjusted to increase, so as to obtain the flow convergence adjustment result.

[0141] In an optional embodiment, the network topology data includes N nodes and M branches of the power grid; the admittance matrix construction unit 302 includes:

[0142] An initial N-dimensional complex matrix construction unit is used to construct an N-dimensional complex matrix with an initial value of 0 based on the N nodes ;

[0143] The first adjustment unit of the N-dimensional complex matrix is ​​used to traverse the N nodes. There is a branch to ground, and the equivalent impedance of the branch to ground is season The number of Increase ,get ;

[0144] The equivalent impedance definition unit is used to traverse the M branches and define nodes With node The equivalent impedance between ;

[0145] The first admittance matrix construction unit is used to respectively set The number of and Increase , number of Increase , number of Increase , obtain the first admittance matrix of the complete network before shutting down the shut-down branch ;

[0146] The second N-dimensional complex matrix adjustment unit is used to adjust The number of 、 、 The real part of is set to 0, and we get ;

[0147] The second admittance matrix construction unit is used to respectively set The number of and Increase , number of Increase , number of Increase , obtain the second admittance matrix of the complete network before shutting down the shut-down branch ;

[0148] The third N-dimensional complex matrix adjustment unit is used to traverse the branches of the M branches except the out-of-service branch and define the node With node The equivalent impedance between ,get ;

[0149] The fourth adjustment unit of the N-dimensional complex matrix is ​​used to adjust The number of 、 、 The real part of is set to 0, and we get ;

[0150] The third admittance matrix construction unit is used to respectively set The number of and Increase , number of Increase , number of Increase , obtain the third admittance matrix of the complete network after shutting down the outage branch .

[0151] In an optional embodiment, the out-of-service branch is the m-th branch among the M branches, and the nodes connected to the m-th branch are node s and node t respectively; the electrical distance node solving unit 303 includes:

[0152] N-dimensional vector first setting unit, used to set the N-dimensional vector , The sth element in is 1.0, and the rest are 0;

[0153] N-dimensional vector second setting unit, used to set the N-dimensional vector ;

[0154] A minimum distance node determination unit is configured to determine a node based on the first admittance matrix , by solving Obtain the The value of Filter out the node whose absolute value is greater than 0 and whose numerical value corresponds to the smallest serial number from all the values ​​as the minimum distance node with the smallest electrical distance to the outage branch;

[0155] The electrical distance maximum node determination unit is used to determine the All values ​​of are sorted from large to small according to absolute value, and nodes corresponding to a preset number of serial numbers are selected from them in descending order as nodes with the largest electrical distance.

[0156] In an optional embodiment, the N nodes include S generator nodes; the node power impact sorting unit 304 includes:

[0157] The third N-dimensional vector setting unit is used to traverse the S generator nodes and set the N-dimensional vector , The cth element in is 1.0, the rth element corresponding to the node with the smallest distance is -1.0, and the rest are 0;

[0158] The fourth N-dimensional vector setting unit is used to set the N-dimensional vector ;

[0159] N-dimensional vector first solving unit for the second admittance matrix , by solving Obtain the The numerical value of

[0160] Node power impact definition unit, used to define node power impact ,in, 、 They are The sth and tth elements of is the reactance of the outage branch;

[0161] Node power impact calculation unit, used to calculate the power of all generator nodes value, and all the generator nodes The value is divided into multiple positive Values ​​and multiple negative value;

[0162] Positive impact node sorting unit, used for The value is sorted from large to small for all The generator nodes with positive values ​​are sorted to obtain the positive impact nodes that are sorted from large to small in terms of the positive impact on node power when the outage branch is shut down;

[0163] The negative impact node sorting unit is used to sort the nodes according to the negative The absolute value of the value is in descending order for all The generator nodes with negative values ​​are sorted, and the negative impact nodes caused by the negative impact on node power when the outage branch is shut down are obtained and sorted from large to small.

[0164] In an optional embodiment, the reactive power compensation capability node sorting unit 305 includes:

[0165] The fifth N-dimensional vector setting unit is used to traverse each of the nodes with the largest electrical distance and set the N-dimensional vector , The cth element in is 1.0, the rth element corresponding to the node with the smallest distance is -1.0, and the rest are 0;

[0166] The sixth N-dimensional vector setting unit is used to set the N-dimensional vector ;

[0167] The second N-dimensional vector solving unit is used to solve the problem based on the third admittance matrix , by solving Obtain the The numerical value of

[0168] The maximum deviation node screening unit is used to compare the node c in the With the , and select the preset E nodes with the largest deviation values ​​from them;

[0169] The reactive compensation node sorting unit is used to take the union of the E nodes in each group screened out, and sort all the nodes with reactive compensation capability obtained after taking the union in descending order according to the deviation value, so as to obtain the reactive compensation nodes whose voltage changes before and after the outage are sorted in descending order.

[0170] In an optional embodiment, the active power adjustment unit 306 includes:

[0171] a reactor reduction unit, configured to reduce one group of reactors for each reactive compensation node when one or more groups of reactors have been previously put into use at the reactive compensation node;

[0172] The capacitor input unit is used to input a group of capacitors when the reactive compensation node has not previously input a reactor.

[0173] In an optional embodiment, the active power adjustment unit 306 includes:

[0174] a first active output reduction adjustment execution unit, configured to, for a first positive influence node ranked first among the multiple positive influence nodes, directly subtract the preset power target value from the first current output to complete the active output reduction adjustment when it is determined that the first current output of the first positive influence node is greater than or equal to a preset power target value;

[0175] a second active output reduction adjustment execution unit, configured to, when determining that the first current output of the first positively impacting node is less than the preset power target value, set the output of the first positively impacting node to 0, and to cause the difference between the first current output and the preset power target value to be subsequently adjusted for active output reduction by the positively impacting nodes other than the first positively impacting node in accordance with the active output reduction adjustment method of the first positively impacting node;

[0176] The first active output increase adjustment execution unit is configured to, for a first negatively impacting node ranked first among the multiple negatively impacting nodes, directly increase the preset power target value based on the second current output when it is determined that the difference between the maximum output of the first negatively impacting node and the second current output is greater than or equal to a preset power target value, thereby completing the active output increase adjustment;

[0177] The second execution unit for active output increase adjustment is used to adjust the output of the first negative impact node to the maximum output when it is determined that the difference between the maximum output of the first negative impact node and the second current output is less than the preset power target value. The difference between the preset power target value and the maximum output is performed according to the active output increase adjustment method of the first negative impact node, and the subsequent active output increase adjustment is performed by the negative impact nodes other than the first negative impact node.

[0178] In an optional embodiment, the device further includes:

[0179] a power flow calculation re-execution unit, configured to re-calculate the power flow based on the power flow convergence adjustment result after completing the active power output adjustment;

[0180] The first execution unit for ending adjustment is configured to end adjustment when the current power flow calculation result indicates that the power flow has converged, and use the power flow convergence adjustment result as the final operation mode.

[0181] In an optional embodiment, the device further includes:

[0182] an active power output adjustment jump cycle execution unit, configured to, when the current power flow calculation result indicates that the power flow has not converged and the current adjustment cycle number has not reached a preset upper limit, use the power flow convergence adjustment result as the current operation mode and re-jump to the reactive power compensation capacity execution step of the reactive power compensation node;

[0183] The second execution unit for ending adjustment is configured to stop adjustment and output an adjustment failure result when the current power flow calculation result indicates that the power flow does not converge and the current adjustment cycle number reaches a preset upper limit.

[0184] As for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the aforementioned method embodiment.

[0185] It should be noted that, in order to enable those skilled in the art to better distinguish data of the same type but with different actual meanings, some technical features are distinguished and described using terms such as first and second in the embodiments of the present invention. Terms such as first and second are only used to distinguish data and have no other special meanings. It can be understood that the present invention does not impose any restrictions on this.

[0186] An embodiment of the present invention further provides an electronic device, the device including a processor and a memory:

[0187] The memory is used to store program codes and transmit the program codes to the processor;

[0188] The processor is configured to execute the power flow convergence adjustment method in a power system maintenance mode according to any embodiment of the present invention according to the instructions in the program code.

[0189] An embodiment of the present invention further provides a computer-readable storage medium for storing program code, and the program code is used to execute the power flow convergence adjustment method in the power system maintenance mode according to any embodiment of the present invention.

[0190] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0191] In the several embodiments provided by the present invention, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interface, device or unit, which can be electrical, mechanical or other forms.

[0192] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0193] In addition, the functional units in the various embodiments of the present invention may be integrated into a single processing unit, each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0194] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes various media that can store program code, such as a USB flash drive, a mobile hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0195] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments can still be modified, or some of the technical features thereof can be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for adjusting power flow convergence in a power system maintenance mode, characterized in that: include: Obtain network topology data of the power grid and determine at least one outage branch line that needs to be shut down for maintenance; For each of the outage branches, based on the network topology data, constructing a first admittance matrix and a second admittance matrix of the complete network before the outage branch is shut down, and a third admittance matrix after the outage branch is shut down; Solve the minimum distance node of the outage branch with the minimum electrical distance according to the first admittance matrix, and simultaneously screen out a preset number of maximum electrical distance nodes; sorting node power impacts by combining the second admittance matrix and the node with the minimum distance to obtain a plurality of positively impacted nodes and a plurality of negatively impacted nodes; sorting nodes by reactive compensation capability based on the third admittance matrix, the node with the smallest distance, and each node with the largest electrical distance, to obtain a plurality of reactive compensation nodes; Improve the reactive compensation capacity of each of the reactive compensation nodes and recalculate the flow. When the flow calculation result indicates that the flow does not converge, based on the preset power target value, adjust the active output of the multiple positively impacted nodes to reduce the active output, and at the same time adjust the active output of the multiple negatively impacted nodes to increase the active output, so as to obtain the flow convergence adjustment result.

2. The power flow convergence adjustment method according to claim 1, characterized in that: The network topology data includes N nodes and M branches of the power grid; and constructing a first admittance matrix and a second admittance matrix of the complete network before shutting down the shut-down branch, and a third admittance matrix after shutting down the shut-down branch based on the network topology data, comprising: Based on the N nodes, construct an N-dimensional complex matrix with an initial value of 0 ; Traverse the N nodes, when the node There is a branch to ground, and the equivalent impedance of the branch to ground is season The number of Increase ,get ; Traverse the M branches and define the nodes With node The equivalent impedance between ; Separate orders The number of and Increase , number of Increase , number of Increase , obtain the first admittance matrix of the complete network before shutting down the shut-down branch ; Respectively The number of 、 、 The real part of is set to 0, and we get ; Separate orders The number of and Increase , number of Increase , number of Increase , obtain the second admittance matrix of the complete network before shutting down the shut-down branch ; Traverse the M branches except the outage branch and define the node With node The equivalent impedance between ,get ; Respectively The number of 、 、 The real part of is set to 0, and we get ; Separate orders The number of and Increase , number of Increase , number of Increase , obtain the third admittance matrix of the complete network after shutting down the outage branch .

3. The power flow convergence adjustment method according to claim 2, characterized in that: The out-of-service branch is the m-th branch among the M branches, and the nodes connected to the m-th branch are node s and node t respectively; solving the minimum distance node with the minimum electrical distance of the out-of-service branch according to the first admittance matrix, and simultaneously screening out a preset number of nodes with maximum electrical distances, includes: Set N-dimensional vector , The sth element in is 1.0, and the rest are 0; Set N-dimensional vector ; Based on the first admittance matrix , by solving Obtain the The value of Filter out the node whose absolute value is greater than 0 and whose numerical value corresponds to the smallest serial number from all the values ​​as the minimum distance node with the smallest electrical distance to the outage branch; Regarding the All values ​​of are sorted from large to small according to absolute value, and nodes corresponding to a preset number of serial numbers are selected from them in descending order as nodes with the largest electrical distance.

4. The power flow convergence adjustment method according to claim 3, characterized in that: The N nodes include S generator nodes; and the node power impact sorting is performed in combination with the second admittance matrix and the node with the minimum distance to obtain a plurality of positive impact nodes and a plurality of negative impact nodes, including: Traverse the S generator nodes and set the N-dimensional vector , The cth element in is 1.0, the rth element corresponding to the node with the smallest distance is -1.0, and the rest are 0; Set N-dimensional vector ; Based on the second admittance matrix , by solving Obtain the The value of Let node power affect ,in, 、 They are The sth and tth elements of is the reactance of the outage branch; Calculate the total number of generator nodes value, and all the generator nodes The value is divided into multiple positive Values ​​and multiple negative value; According to the stated The value is sorted from large to small for all The generator nodes with positive values ​​are sorted to obtain the positive impact nodes that are sorted from large to small in terms of the positive impact on node power when the outage branch is shut down; According to the negative The absolute value of the value is in descending order for all The generator nodes with negative values ​​are sorted, and the negative impact nodes caused by the negative impact on node power when the outage branch is shut down are obtained and sorted from large to small.

5. The power flow convergence adjustment method according to claim 4, characterized in that: The step of sorting nodes by reactive compensation capability by combining the third admittance matrix, the node with the smallest distance, and each node with the largest electrical distance to obtain a plurality of reactive compensation nodes includes: Traverse each of the nodes with the largest electrical distance and set the N-dimensional vector , The cth element in is 1.0, the rth element corresponding to the node with the smallest distance is -1.0, and the rest are 0; Set N-dimensional vector ; Based on the third admittance matrix , by solving Obtain the The numerical value of For each node c, compare the node c in the With the , and select the preset E nodes with the largest deviation values ​​from them; The E nodes in each group selected are combined, and all nodes with reactive compensation capability obtained after the combination are sorted in descending order according to the deviation value, so as to obtain reactive compensation nodes whose voltage changes before and after the outage are sorted in descending order.

6. The power flow convergence adjustment method according to claim 5, characterized in that: The step of increasing the reactive compensation capacity of each reactive compensation node includes: For each reactive power compensation node, when one or more groups of reactors have been previously put into use at the reactive power compensation node, reducing one of the groups of reactors; When the reactive power compensation node has not previously been put into operation with a reactor, a group of capacitors is put into operation.

7. The power flow convergence adjustment method according to claim 4, characterized in that: The adjusting the active output of the plurality of positively impacted nodes to decrease based on the preset power target value and adjusting the active output of the plurality of negatively impacted nodes to increase based on the preset power target value includes: For a first positive influence node ranked first among the multiple positive influence nodes, when it is determined that a first current output of the first positive influence node is greater than or equal to a preset power target value, directly subtracting the preset power target value from the first current output to complete the active output reduction adjustment; When it is determined that the first current output of the first positively influential node is less than the preset power target value, the output of the first positively influential node is set to 0, and the difference between the first current output and the preset power target value is adjusted by the positively influential nodes other than the first positively influential node in accordance with the active output reduction adjustment method of the first positively influential node; For a first negatively impacting node ranked first among the multiple negatively impacting nodes, when it is determined that the difference between the maximum output of the first negatively impacting node and the second current output is greater than or equal to a preset power target value, directly increasing the preset power target value based on the second current output to complete the active output increase adjustment; When it is determined that the difference between the maximum output of the first negatively impacted node and the second current output is less than the preset power target value, the output of the first negatively impacted node is adjusted to the maximum output, and the difference between the preset power target value and the maximum output is adjusted according to the active output increase adjustment method of the first negatively impacted node, and the negatively impacted nodes other than the first negatively impacted node perform subsequent active output increase adjustments.

8. The power flow convergence adjustment method according to any one of claims 1 to 7, characterized in that: Also includes: After the active power output adjustment is completed, the power flow calculation is re-performed based on the power flow convergence adjustment result; When the current power flow calculation result indicates that the power flow has converged, the adjustment is ended, and the power flow convergence adjustment result is used as the final operation mode.

9. The power flow convergence adjustment method according to claim 8, characterized in that: Also includes: When the current power flow calculation result indicates that the power flow is not converged and the current adjustment cycle number has not reached the preset upper limit, the power flow convergence adjustment result is used as the current operation mode, and the process is re-jumped to the reactive compensation capacity execution step of the reactive compensation node; When the current power flow calculation result indicates that the power flow does not converge, and the current adjustment cycle number reaches a preset upper limit, the adjustment is stopped and an adjustment failure result is output.

10. A power flow convergence adjustment device in a power system maintenance mode, characterized in that: include: A data acquisition unit, configured to acquire network topology data of the power grid and determine at least one outage branch line that needs to be shut down for maintenance; An admittance matrix construction unit is configured to construct, for each of the outage branches, a first admittance matrix and a second admittance matrix of the complete network before the outage branch is shut down, and a third admittance matrix after the outage branch is shut down, based on the network topology data; an electrical distance node solving unit, configured to solve the minimum distance node having the minimum electrical distance to the outage branch according to the first admittance matrix, and simultaneously screen out a preset number of maximum electrical distance nodes; a node power impact ranking unit, configured to perform node power impact ranking based on the second admittance matrix and the node with the smallest distance, to obtain a plurality of positively impacted nodes and a plurality of negatively impacted nodes; a reactive compensation capability node sorting unit, configured to sort the reactive compensation capability nodes by combining the third admittance matrix, the minimum distance node, and each of the maximum electrical distance nodes to obtain a plurality of reactive compensation nodes; The active power output adjustment unit is used to increase the reactive compensation capacity of each reactive compensation node and recalculate the power flow. When the power flow calculation result indicates that the power flow does not converge, based on the preset power target value, the active power output of the multiple positive impact nodes is reduced, and the active power output of the multiple negative impact nodes is increased to obtain the power flow convergence adjustment result.

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