CN118100174A - Independent load block identification method and system - Google Patents
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Abstract
The invention discloses an independent load block identification method and system, comprising the following steps: giving out a definition of a load block, and providing a method for quickly generating a whole network load block based on a power distribution network topology simplification method; giving out the definition of the load chain, and providing a method for quickly generating the whole network load chain by an improved depth-first search algorithm based on graph theory; giving definition of independent load blocks, and analyzing alternative relations of the interconnection switches of the whole network based on the associated coupling of load chains; according to the definitions of the load blocks, the load chains and the independent load blocks, an independent load block identification method based on load chain association coupling is provided. According to the scheme, the independent load blocks of the whole network can be finally obtained, and the quantitative evaluation of the importance of the tie switch is carried out by the independent load blocks, so that the method can be used as an important support for the quantitative evaluation of the importance of the tie switch, and the tie switch can be ensured to be carried out smoothly.
Description
Technical Field
The invention relates to the field of power distribution network layering partition mode optimization and safe and stable operation, in particular to an independent load block identification method and system.
Background
With the development of social economy, the load of users is increased year by year, the requirements of users on the power supply capacity and the power supply reliability of a power system are also higher and higher, and the transfer operation is an effective countermeasure, so that the influence caused by local load loss can be reduced, and the flexibility and the schedulability of a network can be improved. However, at the same time, the power distribution network is continuously expanded and developed, the power distribution network is becoming larger and larger in scale and is also becoming more and more complex in structure, and in this case, transfer operation is also becoming complex, and simplification work of developing transfer operation is imperative.
The tie switch plays a critical role in safe and stable operation of the power distribution network, and is also a key factor for simplifying transfer operation. At present, most research regards all tie switches within a power distribution network as tunable devices of the same level, without further subdivision based on their importance for safe and stable operation of the power distribution network. The importance evaluation and division of the tie switch are beneficial to the expansion of dynamic grouping reconstruction work of the feeder lines, help a dispatching center to more efficiently and geographically clear the grouping situation of the feeder lines of the power distribution network, simplify the transfer and analysis processes of the complex power distribution network, and improve the operation efficiency. Therefore, it is necessary to develop quantitative evaluation and classification for importance of tie switches of a power distribution network to advance dynamic grouping of high-efficiency load transfer and feeder lines, but before that, theoretical support for importance quantitative evaluation of tie switches must be provided, so the invention proposes an independent load block identification method as a basic work before importance quantitative evaluation of tie switches.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides an independent load block identification method.
The aim of the invention is realized by the following technical scheme:
an independent load block identification method comprises the following steps:
step 1, defining load blocks, and providing a whole network load block generation method based on a power distribution network topological structure simplification method, wherein the topological complexity of the power distribution network can be greatly reduced by means of a load block concept;
Step 2, defining a load chain, providing a construction method of a power distribution network graph model, and using an improved depth-first search algorithm to realize rapid mining and storage of the whole network load chain;
Step 3, defining independent load blocks, and analyzing the alternative relation of the interconnection switches of the whole network based on the associated coupling of load chains so as to reduce the workload of the step 4;
and step 4, providing an independent load block identification method based on load chain association coupling according to the definitions of the load blocks, the load chains and the independent load blocks.
Further, the definition and the generation method of the load block in the step 1 are as follows:
the load block is defined as: the set formed by a plurality of load nodes between a pair of adjacent switches can be replaced by a brand new load node, and the load node is a load block; the method for generating the full-network load block comprises the following steps:
S201, constructing a branch-node description matrix B, and numbering nodes, branches and switches in a power distribution network respectively to generate n rows of matrixes; the power supply node is used as a starting point of searching, the node is marked, and then the node is stored in a variable storage matrix Q;
；
Wherein n is the branch number, The number of the branch is given to the branch,、The numbers of the two end nodes connected by the branch are respectively given,For the resistance of the branch circuit,For the reactance of the branch,In the case of a branch type,、AndThe circuit comprises a contact switch branch, a sectionalizing switch branch and a common branch;
S202, searching a first node of a variable storage matrix Q in a matrix B And does not contain a switch, and the other end node of the obtained branch is not searchedPut in matrix Q while marking nodesStoring the numbers corresponding to the branches and the corresponding node numbers into an area description matrixWherein l represents the number of the region, matrixThe stored branch information of each row is:
；
where u is the number of branches in region l, The number of the branch is given to the branch,、The node numbers corresponding to the branches are respectively given,、The resistance and reactance of the branches respectively,、The active power injected into the nodes at the two ends of the branch respectively;
S203, circulating the step S202 to find all nodes The connected nodes store all the found nodes in the matrix Q in turn, and all the corresponding branch information is stored in turnIn which the second node of the matrix Q is then to beModified as；
S204, returning to the step S202 until connection search of all nodes in the matrix Q is completed, and updating the area numberEmpty matrix Q, distance from original regionAny node that has recently been unlabeled asStoring the data into a matrix Q;
s205, returning to the step until all nodes in the power distribution network are marked, wherein the step also means that the original topology of the power distribution network is divided into a plurality of different areas, and the different areas represent different load blocks;
S206, for the untagged branch comprising a switch, searching nodes at two ends of the corresponding branch to obtain the area corresponding to the nodes at the two ends, and storing corresponding information of the branch into an area adjacent matrix C after marking the branch, wherein the formula of the matrix C is as follows:
；
Wherein, In order to connect the edges of the areas,、The numbers of the two areas connected by the edges are respectively,The branch corresponding to the edge is numbered,、Numbering nodes at two ends of the branch corresponding to the edge;
S207, the step S206 is circulated until all branches containing the switches are marked, so that the topological relation among all areas of the whole network, namely the topological relation among all load blocks of the whole network, is found, a simplified topological structure is obtained, and the number of load nodes in the original distribution network is greatly reduced.
Further, in the step 2, regarding the definition of the load chain, the construction method of the power distribution network graph model and the mining method of the whole network load chain are as follows:
The load chain is defined as: from the power supply node, only passes through a shortest power supply path of a connecting switch branch and takes the branch as a final branch, and a load chain To start from the power supply node i to connect the switch branchIs a final branch and passes onlyAll of a tie switchThe minimum distance element in the power supply path;
Further, in step 2, before the load chain of the whole network is mined, the topology of the power distribution network needs to be converted into a graph model, and the power distribution network is regarded as a special graph model comprising a plurality of nodes V and edges E Wherein: the nodes comprise transformer stations and main transformer power supply nodes and load nodes, and the sides comprise branches without switches, normally closed sectionalizing switch branches and normally open interconnecting switch branches;
Modeling the nodes by adopting a node adjacency matrix AM, wherein the AM reflects adjacency relation between each node in the graph model, an element of 1 indicates that two nodes have electrical connection, and an element of 0 indicates that the two nodes do not have electrical connection; abstracting arbitrary distribution network topology into graph G composed of branches and nodes for modeling Is composed of point setSum edge setFormed binary group, element in VNodes corresponding to the distribution network, including power supply nodes and load nodes, elements in EA branch corresponding to the distribution network comprises a tie switch and a sectionalizer; drawing of the figureThe corresponding AM can be expressed asM is the total number of nodes,The value principle of (2) is as follows: And (3) with The connection is 1, otherwise, 0, the formula is:
；
and then an improved depth-first search algorithm is used for realizing the rapid excavation and storage of the whole network load chain, and the power supply path of each power supply node is excavated to obtain a power supply link corresponding to a certain contact switch under the power supply node, wherein the steps are as follows:
s301, defining a power supply path from a power supply node i: slave node Starting from the communication path reaching any load node after a series of edges or branches, it is assumed that all power supply paths starting from the power supply node i are gathered,Wherein the power supply paths include n power supply paths, and the j power supply path is；
S302, establishing an empty stack R for sequentially storing nodes through which a power supply path passes, and taking a power supply node i as a first element of stacking;
s303, searching to obtain an adjacent node set of the current stack top node T based on the adjacent matrix AM of the power distribution network graph model ；
S304, the traditional DFS algorithm belongs to a violent search algorithm, and the time complexity is high, so that the traditional DFS algorithm needs to be improved to reduce the time complexity. The improvement measures can start from screening adjacent nodes, and can avoid blind searching of unnecessary paths by DFS, and the improvement measures are as follows: judging whether the node simultaneously meets 3 stacking criteria, if so, stacking and forming a new stack top, and counting a power supply path r of the stack from bottom to top into a path set M; if not, jumping to the next adjacent node in the set to judge; adjacent nodeThe criteria for stacking are: not in the existing stack, The existing path set does not contain the new path, which is not a power node;
S305, if the current stack top node T does not have adjacent nodes meeting the above 3 conditions, performing a stack stripping operation on the T, returning to the step S304, and judging the adjacent nodes of the new stack top node;
s306, returning to the step S304 until elements in the stack are empty, stopping searching, and mining and storing all power supply paths from the power supply node i into a path set M;
The power supply link set obtained by excavation and starting from the power supply node i meets the following conditions: the closed loop is not formed, and only the power supply node i is passed through, so that the open loop operation principle of the power distribution network is met, and any load can be supplied by only one power supply node; by means of improved DFS algorithm, power supply link set from power supply node i can be obtained Power supply pathSequentially recording the passing nodes and branches according to the mode of power supply node-switch branch-path node-switch branch-final node;
S307 for load chain After the above traversal, a power supply path set starting from the power supply node i is obtainedAfter that, findThe power supply path set taking the d branch as the terminal branch and passing through only d tie switchesAnd screening the shortest pathAs a load chain of the communication switch d under the jurisdiction of the power supply node i;
All "node-leg" pairs from power supply node i to tie switch d are recorded in sequence, but the other node of switch d that is far from power supply i side is not recorded, i.e., only "tie switch d that is near power supply i node-leg d" is used as the last element pair of the record.
Further, the definition of the independent coincidence block and the alternative relationship analysis method of the interconnection switch in the step 3 are as follows:
the independent load blocks may be defined as: for a load block, if it occurs on only one load chain, then the load block is referred to as an independent load block;
An independent load block corresponds to a load chain and also corresponds to a tie switch branch, for the tie switch, the number of the independent load blocks is an important standard for measuring whether the tie switch is critical, so that all the independent load blocks of the whole network are required to be identified, before the independent load blocks are identified, the association coupling based on the load chain is carried out, the alternative relation of the tie switches of the whole network is analyzed, all the alternative tie switches are found, the workload is reduced for identifying the independent load blocks, and because the number of the independent load blocks owned by the alternative tie switches is 0, the tie switches can be directly ignored when the independent load blocks are identified, so that the calculation amount is reduced.
Further, in step 3, based on a load chain power supply theory, an analysis is performed on alternative relations between upstream and downstream of a contact switch in the power distribution network; for the tie switch d, assuming that two ends of the tie switch d are respectively connected with the load blocks k and l, and analyzing the alternative relation of the two ends of the tie switch d; for a set of load chains with "k-d" as the final node leg pairEach element except the tie switch d can be completely contained by the other load chains, so that the tie switch d can be completely replaced on its k side; load chain setThe formula is:
；
Wherein, In order to communicate with the collection of switches,Is a power supply node set; according to the alternative relation of the load chain analysis l side, if all the load chains on the two sides of the tie switch can be replaced, the tie switch is completely replaced, the switch is redundant, and the tie switch d meets the requirement of the completely replaced relation on the power supply circuit path as follows:
；
and judging each interconnection switch one by one, and determining the complete replaceable interconnection switch of the whole network.
Further, in the step 4, according to the definitions of the load block, the load chain and the independent load block, an independent load block identification method based on load chain association coupling is provided:
Mathematic the independent load block definition, and propose the feeder independent load block identification rule based on the load chain path correlation: assume that n load chains from a power supply node i are shared in a certain power distribution network, and n tie switches 1,2, …, n-1, n corresponding to the tie switch branch d are used as the load chains from the power supply node i Obtaining a load chain set corresponding to n tie switch branches from a power supply node i; The independent load power supply path corresponding to the interconnection switch branch d is as follows:
。
Further, in step 4, the load block included in the independent power supply path is an independent load block corresponding to the d-th tie switch powered by the power supply node i; the method comprises the following specific steps:
s501, for all load chains taking power supply node i as head node All load chains are converted into character strings, and the character strings are combined into an integral character string L in random sequence;
S502, counting the occurrence times of each character in the character string by using a hash table for the character string L, wherein the specific steps are as follows:
S50201, traversing the character strings, wherein for each character, the character is used as a key of a hash table, and the occurrence times of the character are used as values of the hash table;
s50202, if the character exists in the hash table, adding 1 to the corresponding value, otherwise, adding the key in the hash table, and setting the value to 1;
s50203, after traversing, the key value pairs in the hash table represent the occurrence times of each character in the character string;
s503, reading a key value in the hash table, matching the key value with a corresponding load block number, and obtaining all load chains of each load block in the node taking the power source node i as the head node The number of occurrences of (a);
s504, screening all load blocks with occurrence times of 1, wherein the obtained load blocks are load chains taking a power supply node i as a head node And an independent load block.
In some embodiments, a method performed by a computer system for enabling more precise control of one or more functions of a robotic device for enabling precise control of a tele-robot is disclosed.
According to some embodiments, a computing system includes a processor and a memory storing instructions that, when executed, cause one or more processors to perform the methods described herein. According to some embodiments, an electronic device includes one or more processors, and a memory storing one or more programs; the one or more programs are configured to be executed by the one or more processors, and the one or more programs include instructions for performing or causing to be performed the operations of any of the methods described herein.
The beneficial effects of the invention are as follows:
According to the invention, by proposing the concepts of the load blocks, the load chains and the independent load blocks and corresponding generation and search methods, the independent load blocks of the whole network can be finally obtained, and the importance quantitative evaluation of the tie switch is carried out by means of the independent load blocks, so that the method can be used as an important support for the importance quantitative evaluation work of the tie switch, and can be ensured to be carried out smoothly.
Drawings
FIG. 1 is a schematic diagram of the overall process of the present invention;
FIG. 2 is a schematic diagram of a power distribution network load block generation of the present invention;
FIG. 3 is a schematic diagram of a power distribution network graph model construction according to the present invention;
FIG. 4 is a schematic diagram of power path mining of the present invention;
FIG. 5 is a schematic diagram of the load chain mining of the present invention;
FIG. 6 is a diagram of an independent load block identification method according to the present invention.
Detailed Description
The technical solution of the present invention will be described in further detail with reference to the accompanying drawings, but the scope of the present invention is not limited to the following description.
Referring to fig. 1, fig. 1 is a schematic diagram of the overall method of the present invention, comprising the steps of:
step 1, defining a load block, and providing a whole network load block generation method based on a power distribution network topological structure simplification method, wherein the topological complexity of the power distribution network can be greatly reduced by virtue of a load block concept;
Step 2, giving definition of a load chain, providing a construction method of a power distribution network graph model, and using an improved depth-first search algorithm to realize rapid mining and storage of the whole network load chain;
step 3, defining independent load blocks, and analyzing the alternative relation of the interconnection switches of the whole network based on the associated coupling of load chains so as to reduce the workload of step 4;
And step 4, providing an independent load block identification method based on load chain association coupling according to the definitions of the load blocks, the load chains and the independent load blocks.
Referring to fig. 2, fig. 2 is a schematic diagram of an exemplary power distribution network by means of load block definition using a power distribution network topology simplification method according to the present invention. First, the load nodes L1, L2, L3, L4 form a single area, then the search down is available, L5, L6, L7, L8, L9, L10, L11 form a single area, L12, L13 form a single area, L14 is taken as a single load node, L15, L16, L17, L18 form a single area, L19, L20 form a single area, L21, L22, L23, L24, L25, L26, L27, L28 form a single area, L29, L30, L31, L32, L33 form a single area, L34, L35, L36, L37, L38, L39 form a single area. Through the method, the power distribution network can be divided into a plurality of independent load areas, then the distributed load areas are connected through the sectionalizing switch and the interconnecting switch, and the areas are represented by one equivalent load node, so that the complexity of the topology structure of the power distribution network can be greatly reduced.
Referring to fig. 3, fig. 3 illustrates a schematic construction of a power distribution network by taking a typical four-loop feeder group as an example. The figure comprises four power supply nodes S1, S2, S3 and S4, four feeder outlet sectionalizing switches, four inter-feeder tie switches and a plurality of load blocks (A, B, C, D load nodes after abstraction) between the switches. To describe the topology of the distribution network with a rigorous graph model, a node adjacency matrix AM is used to model it. As shown in the AM table of FIG. 3, AM reflects the adjacency between each node in the graph model, an element of 1 indicates that two nodes are directly connected, and an element of 0 indicates that two nodes are not connected.
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Referring to fig. 4, fig. 4 is a schematic diagram illustrating the power supply path mining method according to the present invention, taking the simple power distribution network of fig. 3 as an example, the power supply path from the power supply node S2 is mined based on an improved depth-first traversal algorithm. First, the neighboring node of S2 has only B, and first, it is determined whether B meets three conditions and found to meet. Therefore, B is stacked to be a new stack top, and a explored path r=S2-B is recorded in the power supply path set started by S2; according to the neighboring nodes S2, A, D of the AM to obtain B, firstly, S2 is judged and the screening criteria 1,2 are not met, and then A is judged to meet 3 criteria. Thus, ase:Sub>A pushes on to become the new top of the stack and records the path r=s2-B-ase:Sub>A; the neighboring nodes of A include S1, B, C, which in turn determine that S1, B are found to be non-conforming to criteria 1 and 2, respectively, and C is conforming to 3 criteria. Thus, C is pushed onto the top of the stack and the path S2-B-A-C is recorded; a, S3 out of the three neighbors of C do not meet 3 criteriase:Sub>A, while D meets the merge stack, recording the new path S2-B-A-C-D. The neighboring nodes of D include B, S, C, none of which meet the three criteria, meaning that deep searches along existing paths have failed to explore new paths, so D pops back to the last branch node C and repeats the above process. Through depth-first traversal, 7 qualified power supply paths from the S2 power supply node are S2-B, S2-B-A, S2-B-A-C, S2-B-A-C-D, S2-B-D, S2-B-D-C, and S2-B-D-C-A respectively.
Referring to fig. 5, fig. 5 is a load chain mining method of the present invention, the topology of fig. 5 is obtained from fig. 2, and the power supply path is obtained from the methods of fig. 3 and 4. By locking the first and last elements of the power supply path, the load chain of the whole network can be directly obtained. Assuming that all the sectionalizers remain closed and the tie switches remain open in the initial situation, then the load blocks L1, L2, L4, L5, L7, L8 are powered by the substation S1, L3 by the substation S2, L6 by the substation S3, and L9 by the substation S4. For S1, the load chain of E3 is { S1-E1-L1-E2-L2-E3}, the load chain of E7 is { S1-E1-L1-E2-L2-E5-L4-E6-L5-E7}, and the load chain of E11 is { S1-E1-L1-E2-L2-E5-L4-E9-L7-E10-L8-E11}. For S2, there is only one load chain of E3 { S2-E4-L3-E3}. For S3, there is only one E7 load chain { S3-E8-L6-E7}. Similarly, S4 contains only one load chain { S4-E12-L9-E11} for E11.
Furthermore, by means of fig. 5, an analysis of the alternative relationship of the tie switches of the whole network is possible. Taking the tie switch E3 as an example, the alternative relationship of its lower end is analyzed first. The load chain taking L2-E3 as the final node branch pair only has { S1-E1-L1-E2-L2-E3}, and can be contained by the load chain { S1-E1-L1-E2-L2-E5-L4-E9-L7-E10-L8-E11} corresponding to E11 without counting E3, so the lower end of E3 is replaceable. The alternative relationship at the upper end is then analyzed, and the load chain with the "L3-E3" as the final node leg pair is only { S2-E4-L3-E3}, and cannot be included by any load chain. Thus, E3 is not a tie switch that can be completely replaced. Similarly, neither E7 nor E11 can be completely replaced by other tie switches.
Referring to FIG. 6, FIG. 6 shows an independent load block identification method of the present invention, for S1, the load chain of E3 is { S1-E1-L1-E2-L2-E3}, the load chain of E7 is { S1-E1-L1-E2-L2-E5-L4-E6-L5-E7}, and the load chain of E11 is { S1-E1-L1-E2-L2-E5-L4-E9-L7-E10-L8-E11}. Further, the hash table analysis can be used to obtain that the load blocks L1 and L2 appear 3 times, L4 appears 2 times, and L5, L7 and L8 appear 1 time, so that S1 is used as a power supply node, the independent load block of E3 is 0, the independent load block of E7 is L5, and the independent load block of E11 is L7 and L8.
By proposing the concepts of the load blocks, the load chains and the independent load blocks and corresponding generation and search methods, the independent load blocks of the whole network can be finally obtained, and the importance quantitative evaluation of the tie switch is carried out by depending on the independent load blocks, so that the invention can be used as an important support for the importance quantitative evaluation work of the tie switch, and can ensure the smooth development of the tie switch.
The foregoing is merely a preferred embodiment of the invention, and it should be understood that the described embodiments are some, but not all, of the embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention. The invention is not limited to the forms disclosed herein, but is not to be construed as limited to the embodiments set forth herein, but is capable of use in various other combinations, modifications and environments and is capable of changes within the scope of the inventive concept, either as a result of the foregoing teachings or as a result of the knowledge or skills in the relevant art. And that modifications and variations which do not depart from the spirit and scope of the invention are intended to be within the scope of the appended claims.
Claims (10)
1. An independent load block identification method is characterized by comprising the following steps:
Step 1, defining a load block: the set formed by a plurality of load nodes between a pair of adjacent switches can be replaced by a brand new load node, and the load node is a load block; thirdly, providing a whole network load block generation method based on a power distribution network topological structure simplification method;
Step 2, defining a load chain: from the power supply node, only a shortest power supply path which passes through one interconnecting switch branch and takes the branch as a final branch; thirdly, providing a construction method of the power distribution network graph model;
Step 3, defining independent load blocks: for a certain load block, if it appears on only one load chain, that load block is an independent load block; analyzing the alternative relation of the interconnection switches of the whole network based on the associated coupling of the load chains;
and step 4, providing an independent load block identification method based on load chain association coupling according to the definitions of the load blocks, the load chains and the independent load blocks.
2. The method according to claim 1, wherein in the step 1, the generating step of the load block is:
S201, constructing a branch-node description matrix B, and numbering nodes, branches and switches in a power distribution network respectively to generate n rows of matrixes; the power supply node is used as a starting point of searching, the node is marked, and then the node is stored in a variable storage matrix Q;
；
Wherein n is the branch number, Numbering branches,/>、/>Respectively numbering two end nodes of branch connection,/>Is the resistance of the branch,/>Is the reactance of the branch,/>For branch type,/>、/>And/>The circuit comprises a contact switch branch, a sectionalizing switch branch and a common branch;
S202, searching a first node of a variable storage matrix Q in a matrix B And does not contain a switch, and the other end node/>, of the obtained branch is not searchedPut in matrix Q while marking nodes/>Storing the numbers corresponding to the branches and the corresponding node numbers into a region description matrix/>Wherein l represents the number of the region, matrix/>The stored branch information of each row is:
；
where u is the number of branches in region l, Numbering branches,/>、/>The node numbers corresponding to the branches are respectively given,、/>Resistance and reactance of the branches, respectively,/>、/>The active power injected into the nodes at the two ends of the branch respectively;
S203, circulating the step S202 to find all nodes The connected nodes sequentially store all the found nodes into a matrix Q, and all corresponding branch information is sequentially stored in the matrix/>In which the second node of matrix Q is then/>Modified as/>；
S204, returning to the step S202 until connection search of all nodes in the matrix Q is completed, and updating the area numberThe matrix Q is emptied and the distance from the original region/>Recently unlabeled arbitrary nodes as/>Storing the data into a matrix Q;
s205, returning to the step S202 until all nodes in the power distribution network are marked;
S206, for the untagged branch comprising a switch, searching nodes at two ends of the corresponding branch for connecting edges of each area to obtain areas corresponding to the nodes at two ends, and storing corresponding information of the branch into an area adjacent matrix C after marking the branch, wherein a formula of the matrix C is as follows:
；
Wherein, For connecting edges of regions,/>、/>The numbers of the two areas connected by the edges,/>For the corresponding branch number of the edge,/>、/>Numbering nodes at two ends of the branch corresponding to the edge;
S207, circulating the step S206 until all branches containing the switches are marked, and finding out the topological relation among all areas of the whole network, namely the topological relation among all load blocks of the whole network, so as to obtain a simplified topological structure.
3. The method according to claim 1, wherein in the step 2, according to the definition of the load chain, the method for mining the load chain comprises: load chainTo start from the power supply node i to connect the switch branch/>Is a terminal branch and passes through only/>All/>, of one tie switchThe minimum distance element in the power supply path.
4. A method of independent load block identification according to claim 3, characterized in that in said step 2, the topology of the distribution network is converted into a graph model before the load chain of the whole network is excavated, the distribution network being regarded as a special graph model comprising several nodes V and edges EWherein: the nodes comprise transformer stations and main transformer power supply nodes and load nodes, and the sides comprise branches without switches, normally closed sectionalizing switch branches and normally open interconnecting switch branches;
Modeling the node adjacency matrix AM by adopting the node adjacency matrix AM, wherein an element of 1 indicates that two nodes are in electrical connection, and an element of 0 indicates that the two nodes are not in electrical connection; abstracting arbitrary distribution network topology into graph G composed of branches and nodes for modeling Is composed of point set/>Sum edge set/>Formed binary group, element/>Nodes corresponding to the distribution network, including power supply nodes and load nodes, elements in E/>A branch corresponding to the distribution network comprises a tie switch and a sectionalizer; graph/>The corresponding AM can be expressed as/>M is the total number of nodes,/>The value principle of (2) is as follows: /(I)And/>The connection is 1, otherwise, 0, the formula is:
；
and then an improved depth-first search algorithm is used for realizing the rapid excavation and storage of the whole network load chain, and the power supply path of each power supply node is excavated to obtain a power supply link corresponding to a certain contact switch under the power supply node, wherein the steps are as follows:
s301, defining a power supply path from a power supply node i: slave node Starting, a communication path reaching any load node after passing through a series of edges or branches, and assuming that all power supply paths starting from a power supply node i are gathered asWherein n power supply paths are included, and the j power supply path is/>；
S302, establishing an empty stack R for sequentially storing nodes through which a power supply path passes, and taking a power supply node i as a first element of stacking;
S303, searching to obtain an adjacent node set of the current stack top node T based on the adjacent matrix AM of the power distribution network graph model ；
S304, judging whether the node simultaneously meets 3 stacking criteria, if so, stacking and forming a new stack top, and counting a power supply path r of the stack from bottom to top into a path set M; if not, jumping to the next adjacent node in the set to judge; adjacent nodeThe criteria for stacking are: /(I)Not in existing stacks,/>The existing path set does not contain a new path, not a power node;
S305, if the current stack top node T does not have adjacent nodes meeting the above 3 conditions, performing a stack stripping operation on the T, returning to the step S304, and judging the adjacent nodes of the new stack top node;
S306, returning to the step S304 until elements in the stack are empty, stopping searching, and mining and storing all power supply paths from the power supply node i into a path set M; the power supply link set obtained by excavation and starting from the power supply node i meets the following conditions: the closed loop is not formed, and only the power supply node i is passed through, so that the open loop operation principle of the power distribution network is met, and any load can be supplied by only one power supply node; by means of improved DFS algorithm, power supply link set from power supply node i can be obtained Power supply path/>Sequentially recording the passing nodes and branches according to the mode of power supply node-switch branch-path node-switch branch-final node;
S307 for load chain After traversing, obtaining a power supply path set/>, which starts from a power supply node iAfter that, find/>In which d branch is taken as a terminal branch and only d one contact switch is used for supplying power to the power path set/>And screening the shortest path/>, among themAs a load chain of the communication switch d under the jurisdiction of the power supply node i;
All "node-leg" pairs from power supply node i to tie switch d are recorded in sequence, but the other node of switch d that is far from power supply i side is not recorded, i.e., only "tie switch d that is near power supply i node-leg d" is used as the last element pair of the record.
5. The method according to claim 1, wherein the method for analyzing the definition of the independent coincidence block and the alternative relationship of the interconnecting switch in the step 3 is as follows:
An independent load block corresponds to a load chain and also corresponds to a tie switch branch, and for the tie switch, the number of the independent load blocks is an important standard for measuring whether the tie switch is critical, so that all independent load blocks of the whole network are required to be identified, and before the independent load blocks are identified, the tie switch alternative relation of the whole network is analyzed to find out all alternative tie switches by carrying out associated coupling based on the load chain.
6. The method according to claim 5, wherein in the step 3, based on a load chain power supply theory, an analysis is performed on an upstream-downstream alternative relationship of a tie switch in the power distribution network; for the tie switch d, assuming that two ends of the tie switch d are respectively connected with the load blocks k and l, and analyzing the alternative relation of the two ends of the tie switch d; load chain set for "k-d" as final node branch pairEach element except the tie switch d can be completely contained by the other load chains, so that the tie switch d can be completely replaced on its k side; load chain set/>The formula is:
；
Wherein, For the tie switch set,/>Is a power supply node set; according to the alternative relation of the load chain analysis l side, if all the load chains on the two sides of the tie switch can be replaced, the tie switch is completely replaced, the switch is redundant, and the tie switch d meets the requirement of the completely replaced relation on the power supply circuit path as follows:
；
and judging each interconnection switch one by one, and determining the complete replaceable interconnection switch of the whole network.
7. The method according to claim 1, wherein in the step 4, according to the definitions of the load block, the load chain and the independent load block, an independent load block identification method based on load chain association coupling is provided:
Mathematic the independent load block definition, and propose the feeder independent load block identification rule based on the load chain path correlation: assume that n load chains from a power supply node i are shared in a certain power distribution network, and n tie switches 1,2, …, n-1, n corresponding to the tie switch branch d are used as the load chains from the power supply node i Obtaining a load chain set/>, corresponding to n tie switch branches, starting from the power supply node i; The independent load power supply path corresponding to the interconnection switch branch d is as follows:
。
8. The method according to claim 7, wherein in the step 4, the load block included in the independent power supply path is an independent load block corresponding to the d-th tie switch powered by the power supply node i; the method comprises the following specific steps:
s501, for all load chains taking power supply node i as head node All load chains are converted into character strings, and the character strings are combined into an integral character string L in random sequence;
S502, counting the occurrence times of each character in the character string by using a hash table for the character string L, wherein the specific steps are as follows:
S50201, traversing the character strings, wherein for each character, the character is used as a key of a hash table, and the occurrence times of the character are used as values of the hash table;
S50202, if the character exists in the hash table, adding 1 to the corresponding value, otherwise, adding the key in the hash table, and setting the value to 1;
s50203, after traversing, the key value pairs in the hash table represent the occurrence times of each character in the character string;
s503, reading a key value in the hash table, matching the key value with a corresponding load block number, and obtaining all load chains of each load block in the node taking the power source node i as the head node The number of occurrences of (a);
s504, screening all load blocks with occurrence times of 1, wherein the obtained load blocks are load chains taking a power supply node i as a head node And an independent load block.
9. An independent load block identification system, characterized in that the system is adapted to perform the method according to any of claims 1-8.
10. A readable storage medium storing instructions which, when executed by one or more processors of a machine, cause the processors to perform the method of any of claims 1-8.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20020161561A1 (en) * | 2001-01-16 | 2002-10-31 | Sridevi Sarma | System and method for association of object sets |
| CN110276532A (en) * | 2019-06-04 | 2019-09-24 | 国网江苏省电力有限公司泰州供电分公司 | A kind of distribution network reliability calculation method of the research based on load piecemeal |
| CN114186858A (en) * | 2021-12-13 | 2022-03-15 | 西安交通大学 | Method and system for evaluating importance of energy storage planning node of power distribution network |
| CN115395557A (en) * | 2022-08-09 | 2022-11-25 | 武汉大学 | Active power distribution network fault rapid recovery method based on directed graph traversal |
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20020161561A1 (en) * | 2001-01-16 | 2002-10-31 | Sridevi Sarma | System and method for association of object sets |
| CN110276532A (en) * | 2019-06-04 | 2019-09-24 | 国网江苏省电力有限公司泰州供电分公司 | A kind of distribution network reliability calculation method of the research based on load piecemeal |
| CN114186858A (en) * | 2021-12-13 | 2022-03-15 | 西安交通大学 | Method and system for evaluating importance of energy storage planning node of power distribution network |
| CN115395557A (en) * | 2022-08-09 | 2022-11-25 | 武汉大学 | Active power distribution network fault rapid recovery method based on directed graph traversal |
Non-Patent Citations (1)
| Title |
|---|
| 胡美玉;胡志坚;邓奥攀;王小飞;汪祥;: "基于元件层级和电源可达性的配电网可靠性评估混合算法", 电力***保护与控制, no. 08 * |
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