CN118484343A - Partition method for power system fault recovery, electronic equipment and storage medium - Google Patents

Abstract

The invention discloses a partitioning method for power system fault recovery, electronic equipment and a storage medium. The method comprises the following steps: determining a node to be recovered and a black start power supply in the power system; selecting a first target node from the nodes to be recovered, determining a partition corresponding to the first target node according to the gains of the partition of the first target node to each black start power supply, and dividing the first target node to the corresponding partition; for each partition, when the nodes to be restored which are already divided into the partitions exist in the partitions, determining alternative nodes according to the nodes to be restored, determining a second target node according to benefits of each alternative node and the partitions, and dividing the second target node into the partitions until all the nodes to be restored are divided into the corresponding partitions, so that the problem of low fault restoration speed of the power system is solved, optimal division of the partitions is realized, the power system can restore faults rapidly, and the fault restoration speed and efficiency of the power system are improved.

Description

Partition method for power system fault recovery, electronic equipment and storage medium

Technical Field

The present invention relates to the field of power systems, and in particular, to a partition method, an electronic device, and a storage medium for recovering a fault of a power system.

Background

Along with the continuous construction of the extra-high voltage power grid in China, the current power system presents an alternating current-direct current deep interconnection mode. The region with more complicated extra-high voltage alternating current network frame is also a region with heavier load and more concentrated, the condition of concentrated feeding of flexible direct current is often existed, the flexible direct current transmission system overcomes the defect that the conventional high voltage direct current transmission system cannot be used as a black start power supply, and has flexible control mode and rapid power adjustment characteristic, and has important effect on accelerating the recovery process of the system. The grid partitioning scheme therefore requires consideration of the impact on the dc feed system.

The traditional power grid partitioning method is often based on engineering experience, a series of partitioning schemes to be selected are obtained, then the partitioning schemes are preferentially selected according to a predetermined evaluation standard, and the dynamic partitioning of the system according to the real-time condition cannot be performed, so that the partitioning effect is poor, and the fault recovery speed is reduced.

Disclosure of Invention

The invention provides a partitioning method for power system fault recovery, electronic equipment and a storage medium, which are used for solving the problem that the power system cannot be recovered quickly after the power system fails.

According to an aspect of the present invention, there is provided a partition method for power system fault recovery, including:

determining a node to be recovered and a black start power supply in the power system;

Selecting a first target node from the nodes to be restored, determining a partition corresponding to the first target node according to the income of the partition of the first target node to each black start power supply, and dividing the first target node to the corresponding partition, wherein the partitions are in one-to-one correspondence with the black start power supplies;

and for each partition, when the nodes to be restored which are already divided into the partitions exist in the partition, determining alternative nodes according to the nodes to be restored, determining a second target node according to the benefits of each alternative node and the partition, and dividing the second target node into the partitions until all the nodes to be restored are divided into the corresponding partitions.

According to another aspect of the present invention, there is provided an electronic apparatus including:

at least one processor, and a memory communicatively coupled to the at least one processor;

The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor, so that the at least one processor can execute the partition method for recovering from the power system fault according to any embodiment of the present invention.

According to another aspect of the present invention, there is provided a computer readable storage medium storing computer instructions for causing a processor to execute a partition method for power system fault recovery according to any one of the embodiments of the present invention.

According to the technical scheme, the node to be recovered and the black start power supply in the power system are determined; selecting a first target node from the nodes to be restored, determining a partition corresponding to the first target node according to the income of the partition of the first target node to each black start power supply, and dividing the first target node to the corresponding partition, wherein the partitions are in one-to-one correspondence with the black start power supplies; for each partition, when the nodes to be restored which are already divided into the partitions exist in the partition, determining alternative nodes according to the nodes to be restored, determining a second target node according to the benefits of the alternative nodes and the partitions, dividing the second target node into the partitions until all the nodes to be restored are divided into the corresponding partitions, solving the problem of slower power system fault restoration speed, determining all the nodes to be restored and a black start power supply in the power system, selecting a first target node from the nodes to be restored, dividing the nodes into the corresponding partitions according to the benefits of the nodes to be restored, determining the alternative nodes according to the benefits of the nodes to be restored after the nodes to be restored are already divided into the partitions in each partition, selecting the proper second target node according to the benefits of the nodes to be restored and dividing the nodes to the partition, dividing the nodes to be restored into the partitions in sequence, and realizing the optimal division of the partitions, so that the power system can quickly restore the fault, and improving the power system fault restoration speed and efficiency.

It should be understood that the description in this section is not intended to identify key or critical features of the embodiments of the invention or to delineate the scope of the invention. Other features of the present invention will become apparent from the description that follows.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a flow chart of a partitioning method for power system fault recovery according to a first embodiment of the present invention;

FIG. 2 is a flow chart of a partition method for power system fault recovery according to a second embodiment of the present invention;

FIG. 3 is a diagram illustrating a partition provided in accordance with a second embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a partition device for recovering from a power system fault according to a third embodiment of the present invention;

fig. 5 is a schematic structural diagram of an electronic device implementing a partition method for power system fault recovery according to an embodiment of the present invention.

Detailed Description

In order that those skilled in the art will better understand the present invention, a technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in which it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention.

It should be noted that the terms "first," "second," and the like in the description and the claims of the present invention and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments of the invention described herein may be implemented in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements that are expressly listed or inherent to such process, method, article, or apparatus.

Example 1

Fig. 1 is a flowchart of a power system fault recovery partition method according to a first embodiment of the present invention, where the method may be performed by a power system fault recovery partition device, and the power system fault recovery partition device may be implemented in hardware and/or software, and the power system fault recovery partition device may be configured in an electronic device. As shown in fig. 1, the method includes:

S101, determining a node to be restored and a black start power supply in the power system.

In this embodiment, the node to be restored may be understood as a node in the power system that needs to restore a normal operating state, and the node may be a load node, a power generation device, or the like that needs an external device to provide starting power. The black start power source may be a flexible high voltage direct current transmission system VSC-HVDC, a power generating device or the like capable of supplying power to other devices.

In order to ensure that the power system can recover quickly after the fault occurs, VSC-HVDC and power generation equipment capable of generating electricity autonomously are arranged in the power system, and the power system can be used as a black start power supply to supply power for other nodes in the power system after the fault occurs. The power system can also be provided with power generation equipment which cannot generate electricity autonomously, namely after the power system fails, the power generation equipment cannot be started directly and supplies power to other nodes in the system, the power generation equipment can start working after being supplied with power by other black start power supplies, and for the power generation equipment, the power generation equipment can not supply power to other nodes after being supplied with power by the black start power supplies and started, can also cooperate with the black start power supplies to supply power to other nodes in the power system. The black start power supply in the power system is usually determined, namely, the black start power supply can be determined when the power system is built, the number and the positions of the black start power supply can be set according to the service importance degree, the speed requirement on power recovery and the like in the operation process of the power system, and the number and the positions of the black start power supply can be increased or decreased in real time according to the service change and the like.

S102, selecting a first target node from the nodes to be restored, determining a partition corresponding to the first target node according to the gains of the partition of the first target node to each black start power supply, and dividing the first target node to the corresponding partition, wherein the partitions are in one-to-one correspondence with the black start power supplies.

In this embodiment, the first target node may be understood as a node that needs partition division.

The black start power supplies are in one-to-one correspondence with the partitions, namely one black start power supply corresponds to one partition, and the black start power supplies restore the nodes divided into the partitions. Randomly or according to a certain rule, selecting one node from the nodes to be recovered as a first target node, constructing a partition model in advance, calculating the benefits of the partition of the first target node to each partition of the black start power supply through the partition model, determining the partition corresponding to the first target node according to the benefits, for example, selecting the partition with the highest benefits as the partition partitioned by the first target node, and partitioning the first target node to the corresponding partition.

Illustratively, the first target node may select by genetic algorithm, initialize algorithm parameters and populations, construct crossover operators, mutation operators, input labels of genetic algorithm, labels divided into different partitions, e.g., labels of partition 1, labels of partition 2, etc. The proper nodes are selected for division through a genetic algorithm, so that the division efficiency and speed can be improved.

S103, for each partition, when the nodes to be restored which are already divided into the partitions exist in the partition, determining alternative nodes according to the nodes to be restored, determining a second target node according to benefits of each alternative node and the partition, and dividing the second target node into the partitions until all the nodes to be restored are divided into the corresponding partitions.

In this embodiment, the candidate node may be understood as a node that needs to be divided; the second target node is a node which is selected from the candidate nodes and is partitioned.

For each partition, when the node to be restored divided into the partition exists in the partition, one node to be restored is selected from the nodes to be restored divided into the partition, the node to be restored can be selected randomly, the selection can also be performed according to the distance between the node to be restored and the black start power supply of the partition, the alternative node is determined according to the position of the node to be restored, for example, the node directly connected with the node to be restored is used as the alternative node, and in a power system, the number of the alternative nodes can be one or a plurality of the alternative nodes because of the fact that the number of the nodes is more and the connection relation can exist between the nodes, if the connected nodes are already divided into the corresponding partition, the number of the alternative nodes can also be 0, at the moment, the node to be restored can be reselected, and the alternative node is determined until all the nodes to be restored in the power system are divided into the partition. In the dividing process, when a plurality of alternative nodes exist, the benefit of dividing each alternative node into the subarea is calculated, the alternative node with higher benefit is selected as a second target node, and the second target node is divided into the subarea.

When the partition is performed, the embodiment of the application selects the proper partition by calculating the gains of the nodes divided to different partitions as the nodes, and selects the proper nodes by calculating the gains of the different nodes as the partitions, thereby realizing the bidirectional selection and the gain maximization of the partitions and the nodes and improving the fault recovery efficiency. When the partition is performed, the nodes may be selected to be divided into the corresponding partitions, and then the appropriate nodes may be selected according to the nodes in each partition to perform the partition, or may be performed simultaneously, which is not limited in the present application. When the number of the black start power supplies is multiple, the corresponding partitions are multiple, and at this time, the partitions can select nodes in parallel.

The embodiment of the invention provides a partition method for power system fault recovery, which solves the problem of slower power system fault recovery speed, determines all nodes to be recovered and black start power supplies in a power system, selects a first target node from the nodes to be recovered, divides the nodes into corresponding partitions according to gains of the nodes to be recovered to different partitions, determines alternative nodes according to the nodes to be recovered after the nodes to be recovered divided into the partitions exist in each partition, selects a proper second target node according to the gains of the nodes to be recovered and divides the nodes to be recovered into the partitions according to the gains of the nodes to be recovered, and sequentially divides the nodes to be recovered into the corresponding partitions through partition selection of the nodes to be recovered, so that the power system can recover faults rapidly, and the fault recovery speed and efficiency of the power system are improved.

Example two

Fig. 2 is a flowchart of a partition method for recovering from a power system fault according to a second embodiment of the present invention, where the present embodiment is refined based on the foregoing embodiment. As shown in fig. 2, the method includes:

s201, determining a node to be restored and a black start power supply in the power system.

S202, selecting a first target node from the nodes to be restored.

S203, determining first benefits of the first target node divided into the partitions of the black start power supplies.

In this embodiment, the first benefit may be understood as a benefit of the first target node being divided into partitions.

After the first target node is analyzed and divided into the partitions of different black start power supplies, the short circuit ratio, the power transmission distance, the partition effect and the like in the partitions are analyzed, and the benefits are further calculated according to the data, so that the first benefits are obtained.

As an alternative embodiment, the present alternative embodiment further optimizes the first benefit of determining the partition of the first target node into the black start power partition, comprising A1-A4:

a1, determining the short-circuit ratio of each direct-current loop according to the short-circuit capacity and rated power of the converter buses of all direct-current loops in the subareas of the black start power supply, and determining the short-circuit ratio corresponding to the subareas according to the short-circuit ratio of each direct-current loop.

Analyzing all nodes to be recovered in a partition of the black start power supply, determining all direct current loops in the partition, then determining the short-circuit capacity and rated power of a converter bus of each direct current loop, and calculating according to a calculation formula of the short-circuit capacity and the rated power of the converter bus combined with a predetermined short-circuit ratio to obtain the short-circuit ratio of each direct current loop. The magnitudes of the short-circuit ratios of the direct current circuits are compared, and an appropriate short-circuit ratio is selected as the short-circuit ratio of the partition according to the magnitudes of the short-circuit ratios, for example, the maximum short-circuit ratio is used as the short-circuit ratio of the partition.

As an alternative embodiment, the present alternative embodiment further optimizes the determination of the short-circuit ratio of each dc loop according to the short-circuit capacity and rated power of the commutated bus of all dc loops in the partition of the black start power supply, including B1-B3:

B1, determining the short-circuit capacity of a converter bus, the first rated power and the node self-impedance of each direct current loop in the subarea of the black start power supply, and determining the second rated power of other direct current loops and the node mutual impedance between the other direct current loops.

In this embodiment, the first rated power and the second rated power can be understood as the rated power of the dc loop.

For each direct current loop i in the partition of the black start power supply, the short-circuit capacity, the first rated power and the node self-impedance of the direct current loop i are obtained, and meanwhile, the second rated power of other direct current loops j and the node mutual impedance between the other direct current loops j and the direct current loop i are obtained.

The short-circuit capacity, rated power, node self-impedance and node mutual impedance between each direct current loop and other direct current loops can be predetermined or determined in the partitioning process, and the determination mode of the data is not limited.

And B2, calculating the ratio of the node self-impedance to the node mutual impedance of each other direct current loop, multiplying the ratio by the second rated power of the corresponding direct current loop, accumulating and summing the products corresponding to each other direct current loop, and adding the value obtained by accumulating and summing with the first rated power to obtain the power sum.

And B3, determining the ratio of the short-circuit capacity of the converter bus to the sum of the power as the short-circuit ratio of the direct current loop.

Exemplary, the embodiment of the application provides a calculation formula of a short circuit ratio. And assuming that the rectifying side power grid of the VSC-HVDC and the direct current transmission line are in a normal running state, and equivalent the VSC-HVDC system and the connected external power grid as a black start power supply of the receiving end system. The calculation formula of the short-circuit ratio is as follows:

Wherein M _i is the short-circuit ratio of the ith DC, and S _ac,i represents the short-circuit capacity of the conversion bus of the ith DC; p _d,i is the rated power of the ith dc (i.e., the first rated power), P _d,j is the rated power of the jth dc (i.e., the second rated power), and n is the number of dc returns; z _i,i is the node self-impedance between the ith return DC and Z _i,j is the node transimpedance between the ith and jth return DC.

The ith direct current in the formula, namely the ith direct current loop, i takes on the value from 1 to n, and the short-circuit ratio of each direct current loop in the subarea can be calculated. When i=1, calculating the short-circuit ratio of the first direct current loop, wherein the rated power of the first direct current loop is the first rated power, the rated powers of other direct current loops (namely 2 nd-n direct current loops) are the second rated powers, and calculating to obtain the short-circuit ratio of the ith direct current loop.

A2, determining the average transmission distance according to the active power transmitted on all lines in the subarea of the black start power supply, the first target node and the active power absorbed by all nodes to be recovered in the subarea.

In this embodiment, the average power transmission distance may be understood as a distance of power transmission from a black start power supply for power supply to a load node, where the larger the average power transmission distance is, the farther the power transmission distance between a power source point and a load point in a power network is, and the lower the power transmission efficiency is.

The active power transmitted by different lines can be predetermined, and the active power absorbed by each node can also be predetermined. Analyzing all nodes to be recovered in the distinction of the black start power supply, determining lines existing in the partition, further determining active power transmitted on the lines, active power absorbed by the first target node and all nodes to be recovered in the partition, determining the sum of the transmitted active power according to the active power transmitted on all lines, determining the sum of the active power absorbed by the nodes according to the active power absorbed by the first target node and all nodes to be recovered in the partition, and calculating the average transmission distance according to the sum of the absorbed active power and the sum of the transmitted active power.

As an alternative embodiment, the present alternative embodiment further optimizes determining an average transmission distance according to all lines in the partition of the black start power source, active power transmitted on the lines, the first target node, and active power absorbed by all nodes to be restored in the partition, including C1-C4:

and C1, determining all lines after the first target node is divided into the partitions of the black start power supply.

Assuming that the first target node is partitioned into partitions of this black start power, all lines within the partitions at this time are determined.

And C2, determining first power according to the weight of the line and the active power transmitted on the line, and summing the first power corresponding to all the lines to obtain a first power sum.

In this embodiment, the first power may be understood as the power obtained after the active power weighting process transmitted on the line. The weights of different lines can be preset, the weight of each line and the active power transmitted on the line are determined, the active power transmitted on the line is weighted according to the weight of the line, so as to obtain first power, namely the weight of the line multiplies the active power transmitted on the line to obtain first power, and the first powers of all the lines are summed to obtain a first power sum.

And C3, summing the active power absorbed by the first target node and all nodes to be restored in the partition to obtain a second power sum.

And adding and summing the active power absorbed by the first target node and all nodes to be restored in the partition to obtain a second power sum.

And C4, determining the ratio of the first power sum to the second power sum as the average transmission distance.

The average transmission distance is exemplified by the ratio of the sum of the weight of an edge and the product of the active power flowing through the edge to the total active power transmitted by the circuit in the power network, and the calculation formula is as follows:

Wherein D is the average transmission distance, w _l is the weight of the line l, namely the reactance per unit value; p _l is the active power transmitted on line L, L is the total number of lines; p _i is the active power absorbed by node i, and N is the total number of nodes. The larger the average power transmission distance D, the longer the power transmission distance between the power source point and the load point in the power network, and the lower the power transmission efficiency.

In calculating the average transmission distance, since it is assumed that the first target node is divided into the partition at this time, the nodes in the partition include the first target node and all the nodes to be restored that have been divided into the partition, that is, the node i is the first target node and all the nodes to be restored that have been divided into the partition in order.

A3, determining a weighted modularity according to edge weights among nodes in the partition and partition conditions of the nodes, wherein the nodes in the partition comprise a first target node and all nodes to be restored in the partition.

In this embodiment, the weighted modularity may be understood as an evaluation index for measuring the quality of partition division. The partition case includes two nodes in one partition and two nodes not in one partition. And determining the edge weights among the nodes in the partition, and calculating according to the edge weights and the partition conditions and combining a predetermined calculation formula to obtain the weighted modularity.

As an optional embodiment, the optional embodiment further optimizes determining a weighted modularity according to edge weights between nodes in the partition and partition conditions of the nodes, including:

D1, determining the partition weight corresponding to each node combination in the partition.

In this embodiment, the node combination includes two different nodes; partition weights can be understood as weight values obtained by performing operations on edge weights of two nodes in a node combination and partition conditions.

The nodes in the partitions are combined two by two to form different node combinations, e.g., node 1 and node 2, node 1 and node 3, node 2 and node 3, and so on. For each node combination, the partition weight is calculated according to the edge weight between two nodes in the node combination, the variable weight sum of all edges in the partition, the partition condition of the nodes and the nodes, and the like.

And D2, summing all the partition weights to obtain a partition weight sum.

D3, determining the weighted modularity based on the sum of the partition weights and the sum of the edge weights of all edges in the partition.

The ratio of the sum of the partition weights to the sum of the edge weights of all the edges in the partition is calculated, and the weighted modularity is determined from the ratio, for example, half of the ratio is taken as the weighted modularity.

Correspondingly, determining partition weights corresponding to the node combinations, wherein the partition weights comprise D11-D13:

D11, determining the edge weight between two nodes to be evaluated in the node combination.

In this embodiment, the node to be evaluated may be understood as a node included in the node combination. Two nodes in the node combination are denoted as nodes to be evaluated. Since the edge weights between nodes are determined, after two nodes to be evaluated are determined, the edge weights between the two nodes to be evaluated can be directly determined.

And D12, determining the sum of the edge weights of all the edges connected with the nodes to be evaluated according to each node to be evaluated, multiplying the sum of the edge weights corresponding to each node to be evaluated, and determining the weight ratio according to the sum of the edge weights of all the edges in the product and the partition.

For each node to be evaluated, determining all edges connected with the node to be evaluated, further determining the edge weights of all edges, and calculating the sum of the edge weights of all edges. Multiplying the sum of the edge weights corresponding to the two nodes to be evaluated, calculating the ratio of the product to the sum of the edge weights of all the edges in the partition, and determining the weight ratio according to the ratio, for example, taking half of the ratio as the weight ratio.

And D13, subtracting the weight ratio from the edge weight between the two nodes to be evaluated, and determining the partition weight of the node combination based on the obtained difference and the partition condition of the two nodes to be evaluated.

The edge weight between two nodes to be evaluated is subtracted by the weight ratio to obtain a difference value, the difference value is processed according to the partition condition of the two nodes to be evaluated, for example, the nodes to be evaluated are in the same partition, the difference value is not processed, the difference value is directly used as the partition weight of the node combination, the nodes to be evaluated are not in the same partition, the difference value is taken as 0, and the partition weight of the node combination is 0.

Exemplary, the embodiment of the application provides a calculation formula of weighted modularity:

Wherein Q is a weighted modularity, e _i,j represents an edge weight between node i and node j; k _i represents the sum of the edge weights of all edges connected to node i, and k _j represents the sum of the edge weights of all edges connected to node j; m represents the sum of edge weights of all edges in the network; delta (i, j) represents the partition condition of the node i and the node j, and if the node i and the node j are in the same partition, the value is 1, otherwise, the value is 0. The larger the modularity Q value, the better the partition quality. When the weighted modularity is calculated through the formula, the node combinations of each group are not repeated.

And A4, determining the first benefit according to the short circuit ratio, the average power transmission distance and the weighted modularity corresponding to the partition.

And determining the optimal benefit according to the short circuit ratio, the average power transmission distance and the weighted modularity corresponding to the partition, and taking the optimal benefit as the first benefit.

Illustratively, the receiver power system optimization partition model expression considering VSC-HVDC access is:

Wherein the minimum of f1, f2, and f3 is the first benefit.

It should be noted that in calculating the first benefit, if the black start power source is VSC-HVDC, the short circuit ratio may not be calculated and may be marked as a null value. The short circuit ratio, average transmission distance, and weighted modularity may be used as partition indicators to evaluate the partition. The short-circuit ratio, the average transmission distance and the weighted modularity may also form a partition model for partitioning by the partition model.

S204, comparing the first benefits, and determining the partition corresponding to the largest first benefit as a target partition.

In this embodiment, the target partition may be understood as a partition selected from a plurality of partitions, and the first target node is partitioned to the partition with the largest benefit. And comparing the first benefits, determining a partition corresponding to the first benefit with the maximum first benefit, and determining the partition as a target partition.

S205, if the partition constraint condition is met by dividing the first target node into the target partitions, determining the target partitions as the partitions corresponding to the first target node, and dividing the first target node into the corresponding partitions.

In this embodiment, the partition constraint may be understood as a constraint for determining whether the partition is reasonable, for example, one or more of a power balance constraint, a partition size constraint, a multi-feed short ratio constraint, and the like.

The method comprises the steps of pre-determining device partition constraint conditions, judging whether partition constraint conditions are met by dividing a first target node into target partitions, for example, whether the scale of the target partitions meets partition scale constraint after the first target node is divided into the target partitions, whether the power of the partitions meets power balance constraint, and the like; and if the partition constraint condition is met, determining the target partition as a partition corresponding to the first target node, and dividing the first target node into the corresponding partition.

If the partition constraint condition is not satisfied by dividing the first target node into the target partitions, a new target partition may be selected, for example, a partition corresponding to the second largest first benefit of the first benefits is determined as the target partition, and whether the partition constraint condition is satisfied is continuously determined until a partition satisfying the partition constraint condition is found, and the first target node is divided into the corresponding partitions.

By way of example, embodiments of the present application provide several partition constraints:

(1) Power balance constraint

To ensure stable operation of the genset, it is necessary to ensure that there is sufficient schedulable load in each partition. The sum of the minimum outputs of the units in the partition is less than the total load.

Wherein α is the minimum technical output coefficient; p _Gi is the unit active power of unit node i; p _Di is the load active power value of load node i. N is the total number of nodes.

The unit may be a thermal power unit, a hydroelectric unit, etc.

(2) Partition size constraint

Considering the actual situation of the power grid, one of the partition principles of the parallel recovery of the system is that the sizes of the partitions are approximately balanced.

Where N _D is the number of nodes to be restored; m _li is the shortest distance from node i to the black start power supply; u _max is the maximum partition size allowed by the partition, which is determined by the dispatcher upon recovery.

The shortest distance from the node i to the black start power supply in the embodiment of the application can be the number of nodes from the node i to the node through which the black start power supply passes.

(3) Short circuit ratio constraint

The multi-feed short ratio is not lower than the minimum value, which is generally 3, as shown below.

M_i≥3

Through the method, the partition with the highest benefit can be selected for the node, and partition optimization is achieved by dividing the node into the partition with the highest benefit.

S206, for each partition, when the nodes to be restored which are already divided into the partitions exist in the partition, determining alternative nodes according to the nodes to be restored.

S207, determining benefits between the candidate node and all nodes in the partition for each candidate node, taking the sum of the benefits as a second benefit of the candidate node and the partition, wherein the nodes in the partition comprise a black start power supply and the nodes to be restored which are already divided into the partition.

In this embodiment, the second benefit may be understood as a benefit that the candidate node is divided into the present partition.

And for each candidate node, calculating benefits between the candidate node and all nodes in the partition according to a predetermined calculation formula, a model and the like to obtain a plurality of benefits, wherein the nodes in the partition comprise the black start power supply and all nodes to be restored which are already divided into the partition, namely, the benefits of the candidate node, the black start power supply in the partition and the nodes to be restored are calculated in sequence. And accumulating the benefits to obtain a benefit sum, and taking the benefit sum as a second benefit of the alternative node and the partition.

As an alternative embodiment, the present alternative embodiment further optimizes the determination of revenue between the candidate node and nodes within the partition, including E1-E3:

and E1, determining a first expected benefit corresponding to the candidate node and the node selection cooperation strategy.

In this embodiment, the first expected benefit may be understood as a benefit generated when the candidate node and a certain node select to cooperate.

Determining the probability of selecting cooperation strategies by the nodes in the alternative nodes and the subareas, obtaining gains by the independent power generation recovery system, selecting additional gains by cooperation, risk loss, selecting gains by cooperation increase and the like, and analyzing and calculating the data to obtain a first expected gain.

And E2, determining a second expected benefit corresponding to the candidate node and the node selection non-cooperative strategy.

In this embodiment, the second desired benefit may be understood as a benefit generated when the candidate node and a node select do not cooperate.

Determining the probability of selecting non-cooperative strategies by the nodes in the alternative nodes and the subareas, obtaining benefits by the independent power generation recovery system, selecting benefits with reduced non-cooperative strategies, and the like, and analyzing and calculating the data to obtain a second expected benefit.

And E3, determining benefits between the alternative nodes and the nodes in the subarea according to the first expected benefits, the second expected benefits and the probabilities corresponding to the selected cooperation strategies.

And determining the probability corresponding to the selected cooperative strategy, correspondingly determining the probability corresponding to the selected non-cooperative strategy, weighting the first expected benefits according to the probability corresponding to the selected cooperative strategy, weighting the second expected benefits according to the probability corresponding to the selected non-cooperative strategy, and summing the weighted two benefits to obtain the benefits between the alternative node and the nodes in the partition.

The embodiment of the application provides an evolution game model, which is used for calculating expected benefits and benefits among nodes, and the specific implementation modes are as follows:

In the three-party gaming model involving in restoring the power system, the power plant (i.e. the power generation equipment), the VSC-HVDC and the load nodes are all aimed at maximizing their own interests, i.e. restoring the normal operation of the power system as fast as possible. Because of the asymmetry of the information and the characteristic that each game participant is of limited rationality, each game participant makes own policy actions by predicting and evaluating decisions of other two parties, and finally obtains an acceptable balance policy for all the three parties by continuously playing games and adjusting own policies.

The assumed conditions are as follows:

Condition 1: the VSC-HVDC system can select a 'cooperative' or 'non-cooperative' recovery system behavior strategy according to the actual damage condition of the power grid, such as the fault reason of a node or a line bank, or the output condition of a power plant (namely the active power of a unit node) after the power grid has a major outage, wherein the probability of selecting the 'cooperative' is x (0 is less than or equal to 1), and the probability of selecting the 'non-cooperative' strategy is 1-x.

Condition 2: the power plant and the load node face the same strategy selection, and the probability of selecting a 'cooperative' strategy of the power plant is assumed to be y (y is more than or equal to 0 and less than or equal to 1), and the probability of selecting a 'non-cooperative' strategy is assumed to be 1-y; the probability of the load node selecting a "cooperative" strategy is z (0.ltoreq.z.ltoreq.1), and the probability of the load node selecting a "non-cooperative" strategy is 1-z.

Constructing an evolution game income matrix:

In the game model, three parties are all participation subjects with limited rationality, and the three game parties select decision actions according to own will. For the benefits of the power plant and the load node, the benefit obtained by the independent power generation recovery system is Gi, and the additional benefit Si can be obtained by selecting to cooperate with the other two parties, so that the risk loss Ri is reduced; assuming that the VSC-HVDC system selects a cooperative strategy, the gain obtained increases Bi, and if a non-cooperative strategy is selected, the gain decreases Ci, i=1 for the power plant and i=2 for the load node.

Wherein, each symbol has the following specific meanings:

g1: recovering a power plant, and obtaining a benefit G1 by a system;

And G2: load node recovery, system gain;

S1: the power plant is used as a main body, selecting with whom to cooperate to obtain additional benefits S1;

S2: the load node is the main body and, selecting with whom to cooperate to obtain additional benefits;

R1: risk loss R1 in cooperation with the power plant;

r2: risk loss R2 in cooperation with the load node;

b1: an increase in revenue in cooperation with the power plant B1;

b2: the income increase B2 is cooperated with the load node;

c1: reducing C1 in non-cooperative income with a power plant;

c2: revenue reduction C2 is not coordinated with the load node.

Based on this, the revenue matrix for the game three parties is as follows:

Where U is the total gain (total power) obtained when the VSC-HVDC system selects the cooperative strategy; u' represents the social benefit obtained when the VSC-HVDC system selects a non-cooperative strategy.

And (3) performing evolution path analysis:

Let La be the expected benefit of the VSC-HVDC system under the selection of the cooperative strategy, lb be the expected benefit of the selection of the non-cooperative strategy and L be the average expected benefit, thereby obtaining:

La＝yz(U-B1-B2)+y(1-z)(U-B1+C2)+z(1-y)(U+C1-B2)

+(1-y)(1-z)(U+C1+C2)

Lb＝yzU’+y(1-z)U’+z(1-y)U’+(1-y)(1-z)U’

L＝xLa+(1-x)Lb

let La1 be the expected benefit of the power plant under the selected cooperative strategy, lb1 be the expected benefit of the selected non-cooperative strategy and L1 be the average expected benefit, thereby obtaining:

La1＝xz(G1+S1-R1+B1)+x(1-z)(G1+B1)

+z(1-x)(G1+S1-R1)+(1-x)(1-z)G1

Lb1＝xz(G1-C1)+x(1-z)(G1-C1)+x(1-x)G1+(1-y)(1-z)G1

L1＝yLa1+(1-y)Lb1

let the expected benefit of the load node under the selection cooperation strategy be La2, the expected benefit of the selection non-cooperation strategy be Lb2 and the average expected benefit be L2, thereby obtaining:

La2＝xy(G2+S2-R2+B2)+x(1-y)(G2+B2)

+y(1-x)(G2+S2-R2)+(1-x)(1-y)G2

Lb2＝xy(G2-C2)+x(1-y)(G2-C1)+y(1-x)G2+(1-y)(1-x)G2

L2＝zLa2+(1-z)Lb2

The three-party copied dynamic differential equation is obtained according to Malthusian copied dynamic equation principle, respectively, as follows:

stability analysis:

1) Replication dynamics analysis of VSC-HVDC systems

Achieving an evolution stabilization strategy requires that the replica dynamic equation satisfies H (x) =0 andLet T (y) =u-U' +c1+c2-y (b1+u) -zC2, then H (x) =x (1-x) T (y), whenWhen H (x) =0, t (y) =0,The replication dynamics equation of the VSC-HVDC system has stability at this time. Due toT (y) is a decreasing function, and when y > y', T (y) <0, thusAnd H (x) | _x＝0 =0, where x=0 is the stable solution of the replica dynamic equation. Similarly, when y < y', x=1 is a stable solution of the replica dynamic equation.

2) Dynamic analysis of replication in power plants

Achieving an evolution stabilization strategy requires that the replica dynamic equation satisfies H (y) =0 andLet T (z) =x (B1+C1-1) -z (S1+R1) + zxG +yG1-yzG1, then H (y) =t (1-y) T (z),When (when)When H (y) =0, t (z) =0,The replicated dynamic equations of the power plant have stability at this time. When z > z', then y=0 is a stable solution of the replica dynamic equation. Similarly, when z < z', y=1 is a stable solution to the replica dynamic equation.

3) Dynamic analysis of replication of load nodes

Achieving an evolution stabilization strategy requires that the replica dynamic equation satisfies H (z) =0 andLet T (x) =x (b2+c1) +xy (c1+c2) +z (S2-R2), H (z) =z (1-z) T (x),When (when)When H (z) =0, t (x) =0,The replicated dynamic equation of the load node has stability at this time. When x > x', where x=1 is a stable solution of the replica dynamic equation. Similarly, when x < x', x=is a stable solution to the replica dynamic equation.

And (3) system balance point analysis: simultaneous replication dynamic equations are available

8 Pure strategy solutions for the system are available according to differential equation stability theorem, let H (x) =0, H (y) =0, H (z) =0.

F1(0,0,0),F2(0,1,0),F3(0,0,1),F4(1,0,0),F5(1,1,0),F6(1,0,1),F7(0,1,1),F8(1,1,1)

The objective function model formed by combining the partition indexes and the three-party game is as follows:

It should be noted that in determining the benefits between the candidate node and all the nodes in the partition, the above formula may be selected according to the types of the candidate node and the nodes in the partition to perform calculation, for example, la2 is calculated as a first expected benefit, lb2 is calculated as a second expected benefit, and L2 is the benefits of the candidate node and the nodes in the partition.

S208, comparing the second benefits, and determining the candidate node corresponding to the second benefit with the highest benefit as a target candidate node.

In this embodiment, the target candidate node may be understood as a node selected from among the candidate nodes. And comparing the second benefits, determining the second benefit with the highest benefit, determining the alternative node corresponding to the second benefit as a target alternative node, and selecting the node with the highest benefit for the subarea to achieve the maximization of the benefit and realize subarea optimization.

After determining the second benefit with the highest benefit, whether the second benefit is stable or not can be determined through stability analysis, and if so, the candidate node is taken as a target candidate node.

S209, if the target candidate node is not selected by other partitions, the target candidate node is taken as a second target node.

And judging whether the target alternative node is selected by other partitions at the moment, and if not, directly taking the target alternative node as a second target node.

And S210, if the target candidate node is selected by other partitions and the gains of the target candidate node divided into the partitions meet the dividing requirement, taking the target candidate node as a second target node, and dividing the second target node into the partitions until all the nodes to be restored are divided into the corresponding partitions.

In this embodiment, the partition requirement may be understood as a requirement for determining whether the node is partitioned into a certain partition, and the partition requirement may be preset, for example, whether the benefit of the node partitioning into the partition is highest, whether the node selects the partition, and so on.

And in the dividing process, if the target candidate node is selected by other partitions at the same time, judging whether the benefits of dividing the target candidate node into the partitions meet the dividing requirement. For example, when partition 1 performs partition, node a is selected, node a is simultaneously selected by partition 2, at this time, it is determined whether the benefits of the target candidate node partitioned to partition 1 meet the partition requirement, if so, the target candidate node is taken as a second target node, and the second target node is partitioned to the partition. Judging whether the benefits of dividing the target candidate node into the current partition meet the dividing requirement, calculating the benefits of dividing the target candidate node into the current partition and the benefits of other partitions selected from the target candidate node, wherein the benefits of calculating the target candidate node and each partition can be realized by adopting a first benefit calculating mode (namely a mode of calculating a short circuit ratio, an average power transmission distance and a weighted modularity) or a second benefit calculating mode (namely a mode of calculating a first average expectation and a second average expectation and weighting by selecting a cooperation strategy); comparing the benefits, and if the benefits of the subarea are highest, determining that the subarea requirements are met; if the benefit of the partition is not the highest, the partition requirement is not met, and the target candidate node is partitioned to the partition with the highest benefit. And dividing all the nodes to be restored into corresponding partitions by the dividing method. After all the nodes to be restored are divided into the corresponding partitions, a partition scheme is formed.

The application realizes the partition mainly comprising the following steps:

step 1: the influence of a VSC-HVDC access receiving end system is considered, and a network partition quality evaluation index, a power grid transmission efficiency loss index and a short circuit ratio index function are provided;

The network partition quality evaluation index is weighted modularity, the power grid transmission efficiency loss index is average transmission distance, and the short-circuit ratio index function is short-circuit ratio.

Step 2: initializing algorithm parameters and populations;

Step 3: constructing crossover operators and mutation operators of a genetic algorithm, and inputting partition labels;

step 4: constructing an evolution game income matrix, wherein game parties select decision behaviors according to own will;

step 5: analyzing the evolution paths of the three game parties, and calculating the benefits under the cooperative and non-cooperative strategies;

step 6: analyzing and calculating the stability of the game behavior of the three parties;

Step 7: and combining the partition indexes and the three-party game behaviors to form an objective function model, solving the model and outputting a system partition scheme.

When partitioning, the partitioning is optimized based on the VSC-HVDC access receiving end system of the three-way evolution game, firstly, the influence of the VSC-HVDC access receiving end system is considered, and a network partition quality evaluation index, a power grid power transmission efficiency loss index and a short circuit ratio index function are provided; based on the method, a three-way evolution game model of a power plant, a VSC-HVDC system and a load node is established, the evolution path and strategy stability of each benefit main body are analyzed, and an NSGA-II algorithm is utilized for solving, so that a novel power system division scheme of VSC-HVDC access is obtained, and the method has important significance in accelerating the recovery process of the power system.

By way of example, FIG. 3 provides an illustration of a partition, which is illustrated as being divided into three partitions. Simulations were performed using a modified IEEE 39 node test system, in which nodes 30 and 31 are connected directly to a VSC-HVDC system, which is connected to an external grid, and thus has the ability to quickly supply power, which can be used as a black start power source for a blackout system. The power system division scheme meeting the constraint condition can be obtained through iterative calculation as shown in fig. 3. The power system after the power failure is partitioned, so that the safety and reliability of the subsequent recovery process are ensured.

The embodiment of the application provides a partition method for recovering faults of a power system, which solves the problem of slower recovery speed of the power system, determines benefits through a partition model and game evolution path analysis, calculates benefits of different partitions selected by nodes, and benefits of different nodes selected by the partitions, realizes bidirectional selection of the nodes and the partitions, selects the partition with the highest benefits for the nodes, realizes maximization of the benefits of the nodes, selects the node with the highest benefits for the partitions, realizes maximization of the benefits of the partitions, and further realizes optimal partition of the partitions so as to facilitate rapid recovery of the faults of the power system, and improves the recovery speed and efficiency of the faults of the power system. In addition, when the partitioning is carried out, the influence of the flexible high-voltage direct-current transmission system as a black start power supply on the power system fault recovery is considered, the system short-circuit current level is reduced, the possibility of occurrence of large-scale cascading faults is reduced, and the overall safety and stability level of the system is improved.

Example III

Fig. 4 is a schematic structural diagram of a partition device for recovering from a power system fault according to a third embodiment of the present invention. As shown in fig. 4, the apparatus includes: a node and power determination module 31, a first partition module 32, and a second partition module 33.

The node and power supply determining module 31 is configured to determine a node to be restored and a black start power supply in the power system;

The first partition module 32 is configured to select a first target node from the nodes to be restored, determine a partition corresponding to the first target node according to the benefit of the partition of the first target node to each black-start power supply, and partition the first target node to a corresponding partition, where the partitions are in one-to-one correspondence with the black-start power supplies;

And a second partition module 33, configured to, for each partition, determine, when there is a node to be restored that has been already divided into the partitions, an alternative node according to the node to be restored, determine a second target node according to benefits of each of the alternative nodes and the partitions, and divide the second target node into the partitions until all the nodes to be restored are divided into the corresponding partitions.

The embodiment of the invention provides a partition method for power system fault recovery, which solves the problem of slower power system fault recovery speed, determines all nodes to be recovered and black start power supplies in a power system, selects a first target node from the nodes to be recovered, divides the nodes into corresponding partitions according to gains of the nodes to be recovered to different partitions, determines alternative nodes according to the nodes to be recovered after the nodes to be recovered divided into the partitions exist in each partition, selects a proper second target node according to the gains of the nodes to be recovered and divides the nodes to be recovered into the partitions according to the gains of the nodes to be recovered, and sequentially divides the nodes to be recovered into the corresponding partitions through partition selection of the nodes to be recovered, so that the power system can recover faults rapidly, and the fault recovery speed and efficiency of the power system are improved.

Optionally, the first partition module 32 includes:

a first benefit determining unit configured to determine a first benefit of the first target node divided into the partitions of the black-start power supplies;

The target partition determining unit is used for comparing the first benefits and determining the partition corresponding to the largest first benefit as a target partition;

and the first partition dividing unit is used for determining the target partition as the partition corresponding to the first target node if the first target node is divided into the target partitions and the partition constraint condition is met.

Optionally, the first benefit determining unit includes:

The short-circuit ratio determining subunit is used for determining the short-circuit ratio of each direct-current loop according to the short-circuit capacity and rated power of the converter bus of all the direct-current loops in the subarea of the black start power supply and determining the short-circuit ratio corresponding to the subarea according to the short-circuit ratio of each direct-current loop;

The power transmission distance determining subunit is used for determining an average power transmission distance according to the active power transmitted on all lines in the partition of the black start power supply, the first target node and the active power absorbed by all nodes to be recovered in the partition;

The weighted module degree determining subunit is used for determining weighted module degree according to edge weights among nodes in the partition and partition conditions of the nodes, wherein the nodes in the partition comprise the first target node and all nodes to be restored in the partition;

and the first benefit determining subunit is used for determining the first benefit according to the short circuit ratio, the average power transmission distance and the weighted modularity corresponding to the partition.

Optionally, the short-circuit ratio determining subunit is specifically configured to: determining a short-circuit capacity, a first rated power and a node self-impedance of a commutation bus of each direct current loop in a partition of the black start power supply, and determining a second rated power of other direct current loops and a node mutual impedance between the other direct current loops; calculating the ratio of the node self-impedance to the node mutual impedance of each other direct current loop, multiplying the ratio by the second rated power of the corresponding direct current loop, accumulating and summing the products corresponding to each other direct current loop, and adding the value obtained by accumulating and summing with the first rated power to obtain a power sum; and determining the ratio of the short-circuit capacity of the converter bus to the sum of the power as the short-circuit ratio of the direct current loop.

Optionally, the transmission distance determining subunit is specifically configured to: determining all lines after the first target node is divided into the partitions of the black start power supply; determining first power according to the weight of the line and the active power transmitted on the line, and summing the first power corresponding to all lines to obtain a first power sum; summing the active power absorbed by the first target node and all nodes to be recovered in the partition to obtain a second power sum; and determining the ratio of the first power sum to the second power sum as an average transmission distance.

Optionally, the weighted module degree determining subunit is specifically configured to: determining partition weights corresponding to the node combinations for each node combination in the partition; summing all the partition weights to obtain a partition weight sum; determining a weighted modularity based on the partition weight sum and a sum of edge weights for all edges in the partition;

Correspondingly, the determining the partition weight corresponding to the node combination includes:

Determining edge weights between two nodes to be evaluated in the node combination;

Determining the sum of the edge weights of all edges connected with each node to be evaluated, multiplying the sum of the edge weights corresponding to each node to be evaluated, and determining a weight ratio according to the sum of the product and the edge weights of all edges in the partition;

And subtracting the weight ratio from the edge weight between the two nodes to be evaluated, and determining the partition weight of the node combination based on the obtained difference and the partition condition of the two nodes to be evaluated.

Optionally, the second partition module 33 includes:

A second benefit determining unit, configured to determine, for each candidate node, benefits between the candidate node and all nodes in the partition, and take a sum of benefits as a second benefit of the candidate node and the partition, where the nodes in the partition include a black start power supply and nodes to be restored that have been partitioned to the partition;

The target candidate node determining unit is used for comparing the second benefits and determining a candidate node corresponding to the second benefit with the highest benefit as a target candidate node;

A first node determining unit, configured to take the target candidate node as a second target node if the target candidate node is not selected by other partitions;

And the second node determining unit is used for taking the target candidate node as a second target node if the target candidate node is selected by other partitions and the benefits of the partition of the target candidate node to the partition meet the partition requirement.

Optionally, the second benefit determining unit is specifically configured to: determining a first expected benefit corresponding to the candidate node and the node selection cooperation strategy; determining a second expected benefit corresponding to the candidate node and the node selection non-cooperative strategy; and determining benefits between the alternative nodes and the nodes in the subarea according to the first expected benefits, the second expected benefits and probabilities corresponding to the selected cooperation strategies.

The partition device for power system fault recovery provided by the embodiment of the invention can execute the partition method for power system fault recovery provided by any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the execution method.

Example IV

Fig. 5 shows a schematic diagram of an electronic device 40 that may be used to implement an embodiment of the invention. Electronic devices are intended to represent various forms of digital computers, such as laptops, desktops, workstations, personal digital assistants, servers, blade servers, mainframes, and other appropriate computers. Electronic equipment may also represent various forms of mobile devices, such as personal digital assistants, cellular telephones, smartphones, wearable devices (e.g., helmets, eyeglasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions, are meant to be exemplary only, and are not meant to limit implementations of the inventions described and/or claimed herein.

As shown in fig. 5, the electronic device 40 includes at least one processor 41, and a memory communicatively connected to the at least one processor 41, such as a Read Only Memory (ROM) 42, a Random Access Memory (RAM) 43, etc., in which the memory stores a computer program executable by the at least one processor, and the processor 41 may perform various suitable actions and processes according to the computer program stored in the Read Only Memory (ROM) 42 or the computer program loaded from the storage unit 48 into the Random Access Memory (RAM) 43. In the RAM 43, various programs and data required for the operation of the electronic device 40 may also be stored. The processor 41, the ROM 42 and the RAM 43 are connected to each other via a bus 44. An input/output (I/O) interface 45 is also connected to bus 44.

Various components in electronic device 40 are connected to I/O interface 45, including: an input unit 46 such as a keyboard, a mouse, etc.; an output unit 47 such as various types of displays, speakers, and the like; a storage unit 48 such as a magnetic disk, an optical disk, or the like; and a communication unit 49 such as a network card, modem, wireless communication transceiver, etc. The communication unit 49 allows the electronic device 40 to exchange information/data with other devices via a computer network, such as the internet, and/or various telecommunication networks.

The processor 41 may be various general and/or special purpose processing components with processing and computing capabilities. Some examples of processor 41 include, but are not limited to, a Central Processing Unit (CPU), a Graphics Processing Unit (GPU), various specialized Artificial Intelligence (AI) computing chips, various processors running machine learning model algorithms, digital Signal Processors (DSPs), and any suitable processor, controller, microcontroller, etc. The processor 41 performs the various methods and processes described above, such as the partition method of power system fault recovery.

In some embodiments, the partitioning method of power system failure recovery may be implemented as a computer program tangibly embodied on a computer-readable storage medium, such as storage unit 48. In some embodiments, part or all of the computer program may be loaded and/or installed onto the electronic device 40 via the ROM 42 and/or the communication unit 49. When the computer program is loaded into RAM 43 and executed by processor 41, one or more steps of the above-described partitioning method for power system fault recovery may be performed. Alternatively, in other embodiments, processor 41 may be configured to perform the partition approach of power system failure recovery in any other suitable manner (e.g., by means of firmware).

Various implementations of the systems and techniques described here above may be implemented in digital electronic circuitry, integrated circuit systems, field Programmable Gate Arrays (FPGAs), application Specific Integrated Circuits (ASICs), application Specific Standard Products (ASSPs), systems On Chip (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and/or combinations thereof. These various embodiments may include: implemented in one or more computer programs, the one or more computer programs may be executed and/or interpreted on a programmable system including at least one programmable processor, which may be a special purpose or general-purpose programmable processor, that may receive data and instructions from, and transmit data and instructions to, a storage system, at least one input device, and at least one output device.

A computer program for carrying out methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the computer programs, when executed by the processor, cause the functions/acts specified in the flowchart and/or block diagram block or blocks to be implemented. The computer program may execute entirely on the machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

In the context of the present invention, a computer-readable storage medium may be a tangible medium that can contain, or store a computer program for use by or in connection with an instruction execution system, apparatus, or device. The computer readable storage medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. Alternatively, the computer readable storage medium may be a machine readable signal medium. More specific examples of a machine-readable storage medium would include an electrical connection based on one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

To provide for interaction with a user, the systems and techniques described here can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to a user; and a keyboard and a pointing device (e.g., a mouse or a trackball) through which a user can provide input to the electronic device. Other kinds of devices may also be used to provide for interaction with a user; for example, feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form, including acoustic input, speech input, or tactile input.

The systems and techniques described here can be implemented in a computing system that includes a background component (e.g., as a data server), or that includes a middleware component (e.g., an application server), or that includes a front-end component (e.g., a user computer having a graphical user interface or a web browser through which a user can interact with an implementation of the systems and techniques described here), or any combination of such background, middleware, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: local Area Networks (LANs), wide Area Networks (WANs), blockchain networks, and the internet.

The computing system may include clients and servers. The client and server are typically remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other. The server can be a cloud server, also called a cloud computing server or a cloud host, and is a host product in a cloud computing service system, so that the defects of high management difficulty and weak service expansibility in the traditional physical hosts and VPS service are overcome.

It should be appreciated that various forms of the flows shown above may be used to reorder, add, or delete steps. For example, the steps described in the present invention may be performed in parallel, sequentially, or in a different order, so long as the desired results of the technical solution of the present invention are achieved, and the present invention is not limited herein.

The above embodiments do not limit the scope of the present invention. It will be apparent to those skilled in the art that various modifications, combinations, sub-combinations and alternatives are possible, depending on design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of the present invention.

Claims (10)

1. A method of partitioning for power system fault recovery, comprising:

determining a node to be recovered and a black start power supply in the power system;

Selecting a first target node from the nodes to be restored, determining a partition corresponding to the first target node according to the income of the partition of the first target node to each black start power supply, and dividing the first target node to the corresponding partition, wherein the partitions are in one-to-one correspondence with the black start power supplies;

and for each partition, when the nodes to be restored which are already divided into the partitions exist in the partition, determining alternative nodes according to the nodes to be restored, determining a second target node according to the benefits of each alternative node and the partition, and dividing the second target node into the partitions until all the nodes to be restored are divided into the corresponding partitions.

2. The method of claim 1, wherein the determining the partition corresponding to the first target node according to the benefit of the first target node partitioning into the partitions of each of the black-start power supplies comprises:

Determining a first benefit of the first target node divided into partitions of each of the black-start power supplies;

comparing the first benefits, and determining the partition corresponding to the largest first benefit as a target partition;

and if the first target node is divided into the target partitions and the partition constraint conditions are met, determining the target partitions as the partitions corresponding to the first target node.

3. The method of claim 2, wherein determining a first benefit of the first target node partitioning into the partition of the black-start power source comprises:

Determining the short-circuit ratio of each direct-current loop according to the short-circuit capacity and rated power of the converter buses of all direct-current loops in the subareas of the black start power supply, and determining the short-circuit ratio corresponding to the subareas according to the short-circuit ratio of each direct-current loop;

Determining an average transmission distance according to active power transmitted on all lines in a partition of the black start power supply, a first target node and active power absorbed by all nodes to be recovered in the partition;

Determining a weighted modularity according to edge weights among nodes in the partition and partition conditions of the nodes, wherein the nodes in the partition comprise the first target node and all nodes to be restored in the partition;

and determining a first benefit according to the short circuit ratio, the average power transmission distance and the weighted modularity corresponding to the partition.

4. A method according to claim 3, wherein said determining the short-circuit ratio of each dc circuit based on the converter bus short-circuit capacity and rated power of all dc circuits in the zone of the black start power supply comprises:

Determining a short-circuit capacity, a first rated power and a node self-impedance of a commutation bus of each direct current loop in a partition of the black start power supply, and determining a second rated power of other direct current loops and a node mutual impedance between the other direct current loops;

calculating the ratio of the node self-impedance to the node mutual impedance of each other direct current loop, multiplying the ratio by the second rated power of the corresponding direct current loop, accumulating and summing the products corresponding to each other direct current loop, and adding the value obtained by accumulating and summing with the first rated power to obtain a power sum;

and determining the ratio of the short-circuit capacity of the converter bus to the sum of the power as the short-circuit ratio of the direct current loop.

5. A method according to claim 3, wherein said determining an average transmission distance from all lines in a partition of said black start power supply, active power transmitted on the lines, active power absorbed by a first target node and all nodes to be restored in said partition comprises:

determining all lines after the first target node is divided into the partitions of the black start power supply;

Determining first power according to the weight of the line and the active power transmitted on the line, and summing the first power corresponding to all lines to obtain a first power sum;

Summing the active power absorbed by the first target node and all nodes to be recovered in the partition to obtain a second power sum;

and determining the ratio of the first power sum to the second power sum as an average transmission distance.

6. A method according to claim 3, wherein said determining a weighted modularity based on edge weights between nodes in said partition and partition conditions of nodes comprises:

determining partition weights corresponding to the node combinations for each node combination in the partition;

summing all the partition weights to obtain a partition weight sum;

Determining a weighted modularity based on the partition weight sum and a sum of edge weights for all edges in the partition;

Correspondingly, the determining the partition weight corresponding to the node combination includes:

Determining edge weights between two nodes to be evaluated in the node combination;

Determining the sum of the edge weights of all edges connected with each node to be evaluated, multiplying the sum of the edge weights corresponding to each node to be evaluated, and determining a weight ratio according to the sum of the product and the edge weights of all edges in the partition;

And subtracting the weight ratio from the edge weight between the two nodes to be evaluated, and determining the partition weight of the node combination based on the obtained difference and the partition condition of the two nodes to be evaluated.

7. The method of claim 1, wherein said determining a second target node based on the revenue of each of said candidate nodes and said partition comprises:

determining, for each candidate node, benefits between the candidate node and all nodes in the partition, taking a sum of the benefits as a second benefit of the candidate node and the partition, wherein the nodes in the partition comprise a black start power supply and nodes to be restored which have been divided into the partition;

Comparing the second benefits, and determining the candidate node corresponding to the second benefit with the highest benefit as a target candidate node;

If the target alternative node is not selected by other partitions, the target alternative node is used as a second target node;

And if the target candidate node is selected by other partitions and the benefits of the partition of the target candidate node to the partitions meet the partition requirement, taking the target candidate node as a second target node.

8. The method of claim 7, wherein determining the benefit between the candidate node and the nodes within the partition comprises:

determining a first expected benefit corresponding to the candidate node and the node selection cooperation strategy;

Determining a second expected benefit corresponding to the candidate node and the node selection non-cooperative strategy;

And determining benefits between the alternative nodes and the nodes in the subarea according to the first expected benefits, the second expected benefits and probabilities corresponding to the selected cooperation strategies.

9. An electronic device, the electronic device comprising:

at least one processor, and a memory communicatively coupled to the at least one processor;

Wherein the memory stores a computer program executable by the at least one processor to enable the at least one processor to perform the partition method of power system failure recovery of any of claims 1-8.

10. A computer readable storage medium storing computer instructions for causing a processor to perform the partition method of power system fault recovery of any one of claims 1-8.