CN104810829B

CN104810829B - A kind of network structure simplified process method of power distribution network reconfiguration

Info

Publication number: CN104810829B
Application number: CN201510275149.5A
Authority: CN
Inventors: 盛万兴; 孟晓丽; 唐巍; 张筱慧; 肖碧琳; 马健
Original assignee: State Grid Corp of China SGCC; China Electric Power Research Institute Co Ltd CEPRI; Jinan Power Supply Co of State Grid Shandong Electric Power Co Ltd
Current assignee: State Grid Corp of China SGCC; China Electric Power Research Institute Co Ltd CEPRI; Jinan Power Supply Co of State Grid Shandong Electric Power Co Ltd
Priority date: 2015-05-26
Filing date: 2015-05-26
Publication date: 2017-06-23
Anticipated expiration: 2035-05-26
Also published as: CN104810829A

Abstract

Aiming at the problems of complex distribution network structure, long solution time and slow power flow calculation speed during reconfiguration, the present invention provides a network structure simplification processing method for distribution network reconfiguration, and utilizes the characteristics of the network structure during distribution network reconfiguration , taking the operable switch in the network structure as the boundary, simplifying the network structure into a simplified topology structure composed of several areas, and satisfying the topology constraints of the radial network, quickly generate a topology reconfiguration strategy, and generate a topology reconfiguration strategy every time , when performing a simplified power flow calculation, the simplified power flow model is used to increase the calculation speed, quickly obtain the optimal network structure, and ensure real-time optimal control of the distribution network.

Description

A network structure simplification processing method for distribution network reconfiguration

技术领域technical field

本发明属于配电系统自动化技术领域，具体涉及一种配电网重构的网络结构简化处理方法。The invention belongs to the technical field of power distribution system automation, and in particular relates to a network structure simplification processing method for distribution network reconfiguration.

背景技术Background technique

配电网重构是优化配电系统运行的重要手段，是配电自动化研究的重要内容。配电网具有闭环设计开环运行的特点，网络中常配置大量用于隔离故障的分段开关，以及少量用于提供可选通路的联络开关。根据不同的负荷状况，改变这些开关的状态，以达到调整网络的运行状态的目的。配电网重构就是以平衡网络负荷、消除运行风险、降低网损、减少运行费用为目的，在满足辐射状网络拓扑约束、潮流方程约束、节点电压约束、开关动作次数约束的条件下，调整配电网的网络结构，改善配电网中潮流分布，优化网络运行状态。因此，配电网重构是提高配电系统可靠性、安全性和经济性的重要手段。Distribution network reconfiguration is an important means to optimize the operation of distribution system and an important content of distribution automation research. The distribution network has the characteristics of closed-loop design and open-loop operation. A large number of section switches for isolating faults and a small number of tie switches for providing optional paths are often configured in the network. According to different load conditions, change the state of these switches to achieve the purpose of adjusting the operating state of the network. Distribution network reconfiguration is aimed at balancing network load, eliminating operating risks, reducing network losses, and reducing operating costs. The network structure of the distribution network improves the power flow distribution in the distribution network and optimizes the network operation status. Therefore, distribution network reconfiguration is an important means to improve the reliability, security and economy of distribution system.

配电网络重构的基础在于对配电网络的潮流分析，网络中各个开关的状态不同，导致网络结构有所差别，通过对不同网络结构的潮流分析，当目标函数取得全局最优时，认为该种网络结构下的开关状态最为合理。但往往网络结构复杂，潮流计算需要反复迭代，运算时间较长。因此，如何简化网络结构，提高潮流运算速度，快速优化网络结构，成为网络重构中亟需解决的问题。The basis of power distribution network reconstruction is the power flow analysis of the power distribution network. Different states of switches in the network lead to differences in network structures. Through power flow analysis of different network structures, when the objective function achieves the global optimum, it is considered that The switch state under this kind of network structure is the most reasonable. However, the network structure is often complicated, and the power flow calculation needs repeated iterations, and the calculation time is relatively long. Therefore, how to simplify the network structure, increase the speed of power flow calculation, and quickly optimize the network structure has become an urgent problem to be solved in network reconfiguration.

发明内容Contents of the invention

为了克服上述现有技术的不足，本发明针对配电网结构复杂，重构时求解结果时间长、潮流计算速度慢的问题，提供一种配电网重构的网络结构简化处理方法，利用配电网重构时网络结构的特点，以网络结构中可操作开关作为边界，将网络结构简化为由若干区域构成的简化拓扑结构，在满足辐射状网络拓扑约束下，迅速生成拓扑重构策略，并在每生成一次拓扑重构策略，进行一次潮流简化计算时，利用潮流简化模型提高计算速度，快速得到最优网络结构，确保对配电网进行实时优化控制。In order to overcome the deficiencies of the above-mentioned prior art, the present invention aims at the problems of complex distribution network structure, long solution time and slow power flow calculation speed during reconstruction, and provides a network structure simplified processing method for distribution network reconfiguration. The characteristics of the network structure during power grid reconfiguration, taking the operable switches in the network structure as the boundary, simplify the network structure into a simplified topology structure composed of several regions, and quickly generate a topology reconfiguration strategy under the topology constraints of the radial network. And every time a topology reconfiguration strategy is generated and a power flow simplified calculation is performed, the simplified power flow model is used to increase the calculation speed, quickly obtain the optimal network structure, and ensure real-time optimal control of the distribution network.

为了实现上述发明目的，本发明采取如下技术方案：In order to realize the above-mentioned purpose of the invention, the present invention takes the following technical solutions:

本发明提供一种配电网重构的网络结构简化处理方法，所述方法包括以下步骤：The present invention provides a network structure simplified processing method for reconfiguration of a distribution network. The method includes the following steps:

步骤1：对配电网的网络结构进行区域划分和拓扑简化，得到简化拓扑结构；Step 1: Perform regional division and topology simplification on the network structure of the distribution network to obtain a simplified topology structure;

步骤2：对简化拓扑结构进行重构，生成拓扑重构策略，并对拓扑重构策略进行还原和简化处理；Step 2: Restructure the simplified topology, generate a topology reconstruction strategy, and restore and simplify the topology reconstruction strategy;

步骤3：对还原且经过简化处理的网络结构进行前推回代潮流简化计算，对比分析拓扑重构策略，选取最优网络结构。Step 3: For the restored and simplified network structure, carry out the simplified calculation of forward and backward power flow, compare and analyze the topology reconstruction strategy, and select the optimal network structure.

在对配电网的网络结构进行区域划分和拓扑简化之前，包括：Before regional division and topology simplification of the network structure of the distribution network, including:

(1)对配电网中的节点、支路、开关分别进行编号，即对节点中的负荷节点和电源节点分别进行节点编号，对连接相邻节点的支路进行支路编号，对开关中的分段开关和联络开关进行开关编号，生成支路-节点描述矩阵B，其为n行矩阵，表示为：(1) Number the nodes, branches, and switches in the distribution network, that is, number the load nodes and power nodes in the nodes, number the branches connected to adjacent nodes, and number the branches in the switches. The subsection switch and tie switch of the switch are numbered to generate a branch-node description matrix B, which is a matrix of n rows, expressed as:

其中，n为支路数，b_n,1为支路编号，b_n,2、b_n,3分别为支路连接的两端节点编号，b_n,4为支路的电阻，b_n,5为支路的电抗，b_n,6为支路类型，支路类型包括含有联络开关的支路、含有分段开关的支路以及连接相邻节点的支路；Among them, n is the number of branches, b _n,1 is the number of the branch, b _n,2 and b _n,3 are the numbers of the nodes at both ends of the branch connection respectively, b _n,4 is the resistance of the branch, b _{n, 5} is the reactance of the branch, b _{n, 6} is the type of the branch, the type of the branch includes the branch containing the tie switch, the branch containing the section switch and the branch connecting the adjacent nodes;

负荷节点形成负荷节点矩阵S，其为m行矩阵，表示为：The load nodes form a load node matrix S, which is an m-row matrix, expressed as:

其中，m为负荷节点数，s_m,1为负荷节点编号，s_m,2、s_m,3分别为该负荷节点的有功功率、无功功率；Among them, m is the number of load nodes, s _m,1 is the number of load nodes, s _m,2 and s _m,3 are the active power and reactive power of the load node respectively;

电源节点形成电源节点矩阵E，其为s列矩阵，表示为：The power supply nodes form a power supply node matrix E, which is a matrix of s columns, expressed as:

E＝[e₁ e₂ … e_s]^T (3)E＝[e ₁ e ₂ … e _s ] ^T (3)

其中，s为电源节点数，e_s为第s个电源节点；Among them, s is the number of power supply nodes, and e _s is the sth power supply node;

(2)根据支路-节点描述矩阵B，将末梢分支收缩于主干，近似处理为等效节点，即利用所包含分支点的负荷总量和支路上的近似损耗代替等效节点的负荷大小，减少节点数量，同时更新支路-节点描述矩阵B。(2) According to the branch-node description matrix B, the terminal branch is shrunk to the trunk, and approximated as an equivalent node, that is, the load of the equivalent node is replaced by the total load of the included branch points and the approximate loss on the branch, Reduce the number of nodes and update the branch-node description matrix B at the same time.

所述步骤1中，根据配电网中可操作开关位置，以区域代替区域内节点，对网络结构完成区域划分和拓扑简化，得到简化拓扑结构。In the step 1, according to the position of the operable switch in the distribution network, the nodes in the area are replaced by areas, and the area division and topology simplification of the network structure are completed to obtain a simplified topology structure.

根据配电网中可操作开关位置和支路-节点描述矩阵B，采用广度优先搜索法对网络结构进行区域划分和拓扑简化，具体包括：According to the operable switch position and the branch-node description matrix B in the distribution network, the breadth-first search method is used to divide the network structure and simplify the topology, including:

步骤1-1：将节点作为搜索起始点，标记该节点，并将其放入变量存储矩阵Q中；Step 1-1: Take the node as the starting point of the search, mark the node, and put it into the variable storage matrix Q;

步骤1-2：在支路-节点描述矩阵B中寻找连接变量存储矩阵Q第一个节点q₁，并寻找不含开关且未被标记搜索的支路，将支路另一端负荷节点q₂依次放在变量存储矩阵Q中，同时对节点q₂进行标记，并将支路的支路编号以及其两端节点编号保留在区域描述矩阵Z_l中，其中l为区域编号，l＝1,2,…nzone，nzone为区域数，区域描述矩阵Z_l中每行保存支路信息，并将支路进行标记；区域描述矩阵Z_l为u行矩阵，其表示为：Step 1-2: Find the first node q ₁ of the connection variable storage matrix Q in the branch-node description matrix B, and find a branch that does not contain a switch and is not marked for search, and load the node q ₂ at the other end of the branch Place them in the variable storage matrix Q in sequence, and mark the node _q2 at the same time, and keep the branch number of the branch and the node numbers at both ends of the branch in the area description matrix Z _l , where l is the area number, l=1, 2,...nzone, where nzone is the number of zones, and each row in the zone description matrix Z _l stores branch information and marks the branches; the zone description matrix Z _l is a u-row matrix, which is expressed as:

其中，u为该区域内所含的支路数，z_u,1为该区域中支路编号，z_u,2、z_u,3为该区域中支路两端的节点编号，z_u,4为该区域中支路的电阻，z_u,5为该区域中支路的电抗，z_u,6、z_i,7为该区域中支路两端节点的负荷大小；Among them, u is the number of branches contained in the area, z _u,1 is the branch number in the area, z _u,2 and z _u,3 are the node numbers at both ends of the branch in the area, z _u,4 is the resistance of the branch in this area, z _u,5 is the reactance of the branch in this area, z _u,6 and z _i,7 are the loads of the nodes at both ends of the branch in this area;

步骤1-3：循环步骤1-2，直至找到所有与节点q₁相邻且其支路不含开关的节点，将找到的所有节点依次存入变量存储矩阵Q，所有对应的支路信息依次保存在Z_l后，将变量存储矩阵Q第二个节点q₂修改为q₁；Step 1-3: Repeat steps 1-2 until all nodes adjacent to node q ₁ and whose branches do not contain switches are found, and all found nodes are stored in the variable storage matrix Q in sequence, and all corresponding branch information is sequentially After saving in Z1, modify the _second node _q2 of the variable storage matrix Q to _q1 ;

步骤1-4：返回步骤1-2，直到完成变量存储矩阵Q中所有节点的连接搜索，即完成对某个区域的所有支路及节点的搜索和保存，更新区域编号l＝l+1，清空变量存储矩阵Q，搜索未标记的节点作为节点q₁放入变量存储矩阵Q；Step 1-4: Return to step 1-2 until the connection search of all nodes in the variable storage matrix Q is completed, that is, the search and preservation of all branches and nodes in a certain area are completed, and the area number l=l+1 is updated. Clear the variable storage matrix Q, search for unmarked nodes as node q ₁ and put them into the variable storage matrix Q;

步骤1-5：返回步骤1-2，直到所有节点均被标记，此时网络结构已划分为若干区域；Step 1-5: Return to step 1-2 until all nodes are marked, at this time the network structure has been divided into several areas;

步骤1-6：检查所有支路，搜索未被标记的支路，由于未被标记的支路含有开关，即为连接各个区域的边，得到nbian行的区域邻接矩阵C，表示为：Step 1-6: Check all branches and search for unmarked branches. Since the unmarked branches contain switches, they are the edges connecting each region, and the region adjacency matrix C of nbian rows is obtained, expressed as:

其中，c_nbian,1为连接区域的边，c_nbian,2、c_nbian,3分别为边所连接的两个区域的编号，c_nbian,4为该边对应的支路编号，c_nbian,5、c_nbian,6为边对应的支路两端的节点编号，即区域的边界节点；Among them, c _nbian,1 is the edge connecting the area, c _nbian,2 and c _nbian,3 are the numbers of the two areas connected by the edge respectively, c _nbian,4 is the branch number corresponding to the edge, c _nbian,5 , c _nbian,6 is the node number at both ends of the branch corresponding to the edge, that is, the boundary node of the area;

步骤1-7：对边对应的支路两端的节点d₁、d₂进行搜索，找到节点d₁、d₂分别所属的区域，标记该支路，同时将支路编号、节点编号、所属区域编号、区域边的编号保存到区域邻接矩阵C中；Step 1-7: Search the nodes d ₁ and d ₂ at both ends of the branch corresponding to the edge, find the areas to which the nodes d ₁ and d ₂ respectively belong, mark the branch, and at the same time set the branch number, node number, and area The number and the number of the area edge are saved in the area adjacency matrix C;

步骤1-8：循环步骤1-7，直到所有支路均被标记，找到各个区域间的关系。Steps 1-8: Repeat steps 1-7 until all branches are marked, and find the relationship between each area.

所述步骤2中，利用区域间的邻接关系，生成拓扑重构策略，并根据区域与节点间的对应关系，对该拓扑重构策略进行还原，利用潮流简化模型对还原后的网络结构进行简化处理。In the step 2, the topology reconstruction strategy is generated by using the adjacency relationship between the regions, and the topology reconstruction strategy is restored according to the corresponding relationship between regions and nodes, and the restored network structure is simplified by using the simplified power flow model deal with.

所述步骤2具体包括以下步骤：Described step 2 specifically comprises the following steps:

步骤2-1：根据区域间的邻接关系，采用人工智能方法对简化拓扑结构进行重构，生成拓扑重构策略；Step 2-1: According to the adjacency relationship between regions, the artificial intelligence method is used to reconstruct the simplified topology structure and generate a topology reconstruction strategy;

步骤2-2：根据配电网辐射状结构以及单电源供电的特点，判断生成的拓扑重构策略是否出现孤岛或环网，若是则返回步骤2-1，重新生成拓扑重构策略；否则执行步骤2-3；Step 2-2: According to the radial structure of the distribution network and the characteristics of single power supply, judge whether the generated topology reconfiguration strategy has an island or a ring network, and if so, return to step 2-1 and regenerate the topology reconfiguration strategy; otherwise, execute Step 2-3;

步骤2-3：利用区域与节点的对应关系，对通过拓扑重构策略重构的拓扑结构进行还原；Step 2-3: Using the corresponding relationship between regions and nodes, restore the topology reconstructed through the topology reconstruction strategy;

步骤2-4：利用潮流简化模型对还原后的网络结构进行简化处理。Step 2-4: Use the power flow simplified model to simplify the restored network structure.

所述2-3中，根据生成拓扑重构策略确定各个区域间的连接关系，再通过区域邻接矩阵C找到对应的节点和支路，结合Z₁、Z₂、…、Z_l、…、Z_nzone内部的网络结构，可得到整个配电网网络结构，完成通过拓扑重构策略重构的拓扑结构的还原。In the above 2-3, the connection relationship between each region is determined according to the generated topology reconstruction strategy, and then the corresponding nodes and branches are found through the region adjacency matrix C, combined with Z ₁ , Z ₂ ,..., Z _l ,..., Z The network structure inside _nzone can obtain the entire distribution network network structure, and complete the restoration of the topology structure reconstructed through the topology reconstruction strategy.

所述步骤2-4的潮流简化模型中，对于含有多条支路任一馈线段，当潮流方向由馈线段的首端节点A指向尾端节点B时，首端节点A与尾端节点B间的相电压压降用表示，有：In the simplified power flow model of steps 2-4, for any feeder section containing multiple branches, when the power flow direction is from the head-end node A of the feeder section to the tail-end node B, the head-end node A and the tail-end node B The phase voltage drop between the Indicates that there are:

其中，N为馈线段上节点个数，L_i为第i条支路的长度，为馈线段上首端节点A的相电压，为节点t的复功率，符号*表示共轭；Among them, N is the number of nodes on the feeder segment, L _i is the length of the i-th branch, is the phase voltage of the head-end node A on the feeder section, is the complex power of node t, and the symbol * represents the conjugate;

设馈线段总长度为L，假设馈线段是均匀导线，r、x分别表示馈线段上单位长度的电阻和电抗，则首端节点A到等效节点D的相电压压降及等效节点D到尾端节点B的相电压压降分别表示为：Let the total length of the feeder section be L, assuming that the feeder section is a uniform conductor, and r and x respectively represent the resistance and reactance per unit length of the feeder section, then the phase voltage drop from node A at the head end to the equivalent node D And the phase voltage drop from the equivalent node D to the end node B Respectively expressed as:

其中，为等效节点D的复功率，L_AD为首端节点A到等效节点D的支路长度；in, is the complex power of the equivalent node D, and L _AD is the branch length from the headend node A to the equivalent node D;

结合式(6)-(8)可得：Combining formula (6)-(8) can get:

当潮流方向由馈线段上尾端节点B指向首端节点A时，有：When the power flow direction is from the end node B on the feeder section to the head end node A, there are:

其中，为馈线段上尾端节点B的相电压，L_DB为等效节点D到首端节点A的支路长度，L_i+1为第i+1条支路的长度；in, is the phase voltage of the end node B on the feeder section, L _DB is the branch length from the equivalent node D to the head end node A, L _i+1 is the length of the i+1th branch;

由于L_AD+L_DB＝L，可得：Since L _AD +L _DB = L, we can get:

所述步骤3具体包括以下步骤：Described step 3 specifically comprises the following steps:

步骤3-1：对还原且经过简化处理的网络结构进行前推回代潮流简化计算，根据潮流分析结果计算重构指标；Step 3-1: Carry out forward push-back generation power flow simplification calculation on the restored and simplified network structure, and calculate the reconstruction index according to the power flow analysis results;

步骤3-2：根据重构指标对比分析各个拓扑重构策略，判断拓扑重构策略对应的网络结构是否为满足重构条件的最优网络结构，若满足则选取该网络结构作为最优网络结构，同时输出该网络结构及重构指标；否则返回步骤2-1，重新生成拓扑重构策略。Step 3-2: Compare and analyze each topology reconstruction strategy according to the reconstruction index, and judge whether the network structure corresponding to the topology reconstruction strategy is the optimal network structure that satisfies the reconstruction conditions, and if so, select the network structure as the optimal network structure , and output the network structure and reconstruction index at the same time; otherwise, return to step 2-1 to regenerate the topology reconstruction strategy.

所述步骤3-1具体包括以下步骤：The step 3-1 specifically includes the following steps:

步骤3-1-1：对还原且经过简化处理的网络结构进行前推回代潮流简化计算，得到潮流简化模型中馈线段的首端节点A相电压尾端节点B的相电压以及等效节点D的相电压 Step 3-1-1: Carry forward and back the simplified calculation of power flow for the restored and simplified network structure, and obtain the A-phase voltage of the head-end node of the feeder section in the simplified model of power flow Phase voltage of terminal node B and the phase voltage at the equivalent node D

步骤3-1-2：将和作为已知量，再对网络结构进行潮流简化计算，从网络结构的尾端节点向前递推，判断待求节点是否属于T接点，若待求节点不属于T接点，则执行步骤3-1-3，若待求节点属于T接点，则执行步骤3-1-4；Step 3-1-2: Put with As a known quantity, perform a simplified power flow calculation on the network structure, recursively push forward from the end node of the network structure, and judge whether the node to be requested belongs to a T node. If the node to be requested does not belong to a T node, perform step 3-1 -3, if the node to be requested belongs to the T contact, then perform step 3-1-4;

步骤3-1-3：待求节点不属于T接点时，计算尾端节点k的支路损耗其表示为：Step 3-1-3: When the node to be requested does not belong to the T contact, calculate the branch loss of the tail node k which is expressed as:

其中，L_k为尾端节点k的支路长度，为尾端节点k的相电压，为流过尾端节点k的总功率，P表示总功率，L表示损耗；Among them, L _k is the branch length of the end node k, is the phase voltage at the end node k, is the total power flowing through the end node k, P represents the total power, and L represents the loss;

于是，流过节点k-1的总功率表示为：Then, the total power flowing through node k-1 Expressed as:

其中，为节点k-1的复功率；in, is the complex power of node k-1;

节点k-1的相电压表示为：Phase voltage at node k-1 Expressed as:

步骤3-1-4：待求节点属于T接点时，由于按照潮流方向的逆方向进行递推，尾端节点k下游的相邻馈线段上节点、支路均已知，计算流过尾端节点k的总功率有：Step 3-1-4: When the node to be requested belongs to the T junction, since the recursion is performed in the reverse direction of the power flow direction, the nodes and branches on the adjacent feeder segment downstream of the tail node k are known, and the calculation flows through the tail The total power of node k have:

其中，θ为按照潮流方向尾端节点k下游所有相邻馈线段的集合；v表示按照潮流方向尾端节点k下游所有相邻馈线段；为第v条与节点k相邻的下游馈线上的支路损耗，其中L表示损耗，kv为第v条与尾端节点k相邻的下游馈线段；第v条与节点k相邻的下游馈线端尾端节点通过的总功率，P表示总功率，为节点k的复功率；Among them, θ is the set of all adjacent feeder segments downstream of the tail end node k according to the power flow direction; v represents all adjacent feeder line segments downstream of the tail end node k according to the power flow direction; is the branch loss on the v-th downstream feeder adjacent to node k, where L represents the loss, and kv is the v-th downstream feeder segment adjacent to the end node k; The total power passing through the tail end node of the downstream feeder end adjacent to node k, P represents the total power, is the complex power of node k;

步骤3-1-5：计算网络结构的总线损，有：Step 3-1-5: Calculate the total loss of the network structure, there are:

其中，为网络结构的总线损，为馈线段w的损耗，λ为所有馈线段的集合，w为属于集合λ的馈线段。in, is the total loss of the network structure, is the loss of feeder section w, λ is the set of all feeder sections, and w is the feeder section belonging to the set λ.

与现有技术相比，本发明的有益效果在于：Compared with prior art, the beneficial effect of the present invention is:

1)本发明根据拓扑结构重构时的网络结构特点，对网络结构进行区域划分，简化网络拓扑结构，能够提高生成拓扑重构策略的效率，同时可以快速还原简化网络拓扑；1) According to the characteristics of the network structure during topology reconstruction, the present invention divides the network structure into regions, simplifies the network topology, can improve the efficiency of generating topology reconstruction strategies, and can quickly restore the simplified network topology;

2)本发明得到满足辐射状网络的拓扑重构策略后，对配电网馈线端上的负荷进行等效处理，有效地简化了网络拓扑结构，采用前推回代潮流简化计算可以快速得到简化网络的节点电压；2) After obtaining the topology reconstruction strategy that satisfies the radial network, the present invention performs equivalent processing on the load on the feeder end of the distribution network, which effectively simplifies the network topology structure, and can be quickly simplified by using forward push back generation simplified calculation the node voltage of the network;

3)将简化等效模型首、尾端节点以及等效节点的电压作为已知量，再对未简化网络再进行一次潮流计算，得到整个网络的潮流分布，提高潮流计算速度，有利于快速求解出最优网络结构。3) Taking the voltages of the first and last nodes and equivalent nodes of the simplified equivalent model as known quantities, and then performing a power flow calculation on the unsimplified network to obtain the power flow distribution of the entire network, improve the power flow calculation speed, and facilitate quick solution the optimal network structure.

附图说明Description of drawings

图1是本发明实施例中配电网重构的网络结构简化处理方法流程图。Fig. 1 is a flow chart of a simplified processing method for network structure reconfiguration of a distribution network in an embodiment of the present invention.

具体实施方式detailed description

下面结合附图对本发明作进一步详细说明。The present invention will be described in further detail below in conjunction with the accompanying drawings.

如图1，本发明提供一种配电网重构的网络结构简化处理方法，所述方法包括以下步骤：As shown in Fig. 1, the present invention provides a method for simplifying the network structure of distribution network reconfiguration, the method comprising the following steps:

E＝[e₁ e₂ … e_s]^T (3)E＝[e ₁ e ₂ … e _s ] ^T (3)

结合式(6)-(8)可得：Combining formula (6)-(8) can get:

由于L_AD+L_DB＝L，可得：Since L _AD +L _DB = L, we can get:

其中，为节点k-1的复功率；in, is the complex power of node k-1;

节点k-1的相电压表示为：Phase voltage at node k-1 Expressed as:

最后应当说明的是：以上实施例仅用以说明本发明的技术方案而非对其限制，所属领域的普通技术人员参照上述实施例依然可以对本发明的具体实施方式进行修改或者等同替换，这些未脱离本发明精神和范围的任何修改或者等同替换，均在申请待批的本发明的权利要求保护范围之内。Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Those of ordinary skill in the art can still modify or equivalently replace the specific implementation methods of the present invention with reference to the above embodiments. Any modification or equivalent replacement departing from the spirit and scope of the present invention is within the protection scope of the claims of the present invention pending application.

Claims

1. A network structure simplification processing method of distribution network reconfiguration, is characterized in that: described method comprises the following steps:

Step 1: Perform regional division and topology simplification on the network structure of the distribution network to obtain a simplified topology structure;

Step 2: Restructure the simplified topology, generate a topology reconstruction strategy, and restore and simplify the topology reconstruction strategy;

Step 3: For the restored and simplified network structure, carry out the simplified calculation of power flow forward and backward, compare and analyze the topology reconstruction strategy, and select the optimal network structure;

Before regional division and topology simplification of the network structure of the distribution network, including:

(1) Number the nodes, branches, and switches in the distribution network, that is, number the load nodes and power nodes in the nodes, number the branches connected to adjacent nodes, and number the branches in the switches. The subsection switch and tie switch of the switch are numbered to generate a branch-node description matrix B, which is a matrix of n rows, expressed as:

B B = = [\begin{matrix} {b b}_{11,, 11} & {b b}_{11,, 22} & {b b}_{11,, 33} & {b b}_{11,, 44} & {b b}_{11,, 55} & {b b}_{11,, 66} \\ {b b}_{22,, 11} & {b b}_{22,, 22} & {b b}_{22,, 33} & {b b}_{22,, 44} & {b b}_{22,, 55} & {b b}_{22,, 66} \\ \begin{matrix} . . \\ . . \\ . . \end{matrix} & \begin{matrix} . . \\ . . \\ . . \end{matrix} & \begin{matrix} . . \\ . . \\ . . \end{matrix} & \begin{matrix} . . \\ . . \\ . . \end{matrix} & \begin{matrix} . . \\ . . \\ . . \end{matrix} & \begin{matrix} . . \\ . . \\ . . \end{matrix} \\ {b b}_{n no,, 11} & {b b}_{n no,, 22} & {b b}_{n no,, 33} & {b b}_{n no,, 44} & {b b}_{n no,, 55} & {b b}_{n no,, 66} \end{matrix}] - - - - - - ((11))

Among them, n is the number of branches, b _n,1 is the number of the branch, b _n,2 and b _n,3 are the numbers of the nodes at both ends of the branch connection respectively, b _n,4 is the resistance of the branch, b _{n, 5} is the reactance of the branch, b _{n, 6} is the type of the branch, the type of the branch includes the branch containing the tie switch, the branch containing the section switch and the branch connecting the adjacent nodes;

The load nodes form a load node matrix S, which is a matrix of m rows, expressed as:

S S = = [\begin{matrix} {s the s}_{11,, 11} & {s the s}_{11,, 22} & {s the s}_{11,, 33} \\ {s the s}_{22,, 11} & {s the s}_{22,, 22} & {s the s}_{22,, 33} \\ \begin{matrix} . . \\ . . \\ . . \end{matrix} & \begin{matrix} . . \\ . . \\ . . \end{matrix} & \begin{matrix} . . \\ . . \\ . . \end{matrix} \\ {s the s}_{m m,, 11} & {s the s}_{m m,, 22} & {s the s}_{m m,, 33} \end{matrix}] - - - - - - ((22))

Among them, m is the number of load nodes, s _m,1 is the number of load nodes, s _m,2 and s _m,3 are the active power and reactive power of the load node respectively;

The power supply nodes form a power supply node matrix E, which is a matrix of s columns, expressed as:

E＝[e ₁ e ₂ … e _s ] ^T (3)

Among them, s is the number of power supply nodes, and e _s is the sth power supply node;

(2) According to the branch-node description matrix B, the terminal branch is shrunk to the trunk, and approximately treated as an equivalent node; that is, the load of the equivalent node is replaced by the total load of the included branch points and the approximate loss on the branch, Reduce the number of nodes and update the branch-node description matrix B at the same time.

2. The network structure simplification processing method for distribution network reconfiguration according to claim 1, characterized in that: in the step 1, according to the position of the operable switch in the distribution network, the nodes in the area are replaced by areas, and the network The structure completes area division and topology simplification, and obtains a simplified topology structure.

3. The network structure simplified processing method of distribution network reconfiguration according to claim 2 is characterized in that: according to the operable switch position and branch-node description matrix B in the distribution network, the breadth-first search method is used to search the network Region division and topology simplification are performed on the structure, including:

Step 1-1: Take the node as the starting point of the search, mark the node, and put it into the variable storage matrix Q;

Step 1-2: Find the first node q ₁ of the connection variable storage matrix Q in the branch-node description matrix B, and find a branch that does not contain a switch and is not marked for search, and load the node q ₂ at the other end of the branch Place them in the variable storage matrix Q in sequence, and mark the node _q2 at the same time, and keep the branch number of the branch and the node numbers at both ends of the branch in the area description matrix Z _l , where l is the area number, l=1, 2,...nzone, where nzone is the number of zones, and each row in the zone description matrix Z _l stores branch information and marks the branches; the zone description matrix Z _l is a u-row matrix, which is expressed as:

{Z Z}_{l l} = = [\begin{matrix} {z z}_{11,, 11} & {z z}_{11,, 22} & {z z}_{11,, 33} & {z z}_{11,, 44} & {z z}_{11,, 55} & {z z}_{11,, 66} & {z z}_{11,, 77} \\ {z z}_{22,, 11} & {z z}_{22,, 22} & {z z}_{22,, 33} & {z z}_{22,, 44} & {z z}_{22,, 55} & {z z}_{22,, 66} & {z z}_{22,, 77} \\ \begin{matrix} . . \\ . . \\ . . \end{matrix} & \begin{matrix} . . \\ . . \\ . . \end{matrix} & \begin{matrix} . . \\ . . \\ . . \end{matrix} & \begin{matrix} . . \\ . . \\ . . \end{matrix} & \begin{matrix} . . \\ . . \\ . . \end{matrix} & \begin{matrix} . . \\ . . \\ . . \end{matrix} & \begin{matrix} . . \\ . . \\ . . \end{matrix} \\ {z z}_{u u,, 11} & {z z}_{u u,, 22} & {z z}_{u u,, 33} & {z z}_{u u,, 44} & {z z}_{u u,, 55} & {z z}_{u u,, 66} & {z z}_{u u,, 77} \end{matrix}] - - - - - - ((44))

Among them, u is the number of branches contained in the area, z _u,1 is the branch number in the area, z _u,2 and z _u,3 are the node numbers at both ends of the branch in the area, z _u,4 is the resistance of the branch in this area, z _u,5 is the reactance of the branch in this area, z _u,6 and z _i,7 are the loads of the nodes at both ends of the branch in this area;

Step 1-3: Repeat steps 1-2 until all nodes adjacent to node q ₁ and whose branches do not contain switches are found, and all found nodes are stored in the variable storage matrix Q in sequence, and all corresponding branch information is sequentially After saving in Z1, modify the _second node _q2 of the variable storage matrix Q to _q1 ;

Step 1-4: Return to step 1-2 until the connection search of all nodes in the variable storage matrix Q is completed, that is, the search and preservation of all branches and nodes in a certain area are completed, and the area number l=l+1 is updated. Clear the variable storage matrix Q, search for unmarked nodes as node q ₁ and put them into the variable storage matrix Q;

Step 1-5: Return to step 1-2 until all nodes are marked, at this time the network structure has been divided into several areas;

Steps 1-6: Check all branches and search for unmarked branches. Since unmarked branches contain switches, which are edges connecting various regions, obtain the region adjacency matrix C of nbian rows, expressed as:

C C = = [\begin{matrix} {c c}_{11,, 11} & {c c}_{11,, 22} & {c c}_{11,, 33} & {c c}_{11,, 44} & {c c}_{11,, 55} & {c c}_{11,, 66} \\ {c c}_{22,, 11} & {c c}_{22,, 22} & {c c}_{22,, 33} & {c c}_{22,, 44} & {c c}_{22,, 55} & {c c}_{22,, 66} \\ \begin{matrix} . . \\ . . \\ . . \end{matrix} & \begin{matrix} . . \\ . . \\ . . \end{matrix} & \begin{matrix} . . \\ . . \\ . . \end{matrix} & \begin{matrix} . . \\ . . \\ . . \end{matrix} & \begin{matrix} . . \\ . . \\ . . \end{matrix} & \begin{matrix} . . \\ . . \\ . . \end{matrix} \\ {c c}_{n no b b i i a a n no,, 11} & {c c}_{n no b b i i a a n no,, 22} & {c c}_{n no b b i i a a n no,, 33} & {c c}_{n no b b i i a a n no,, 44} & {c c}_{n no b b i i a a n no,, 55} & {c c}_{n no b b i i a a n no,, 66} \end{matrix}] - - - - - - ((55))

Among them, c _nbian,1 is the edge connecting the area, c _nbian,2 and c _nbian,3 are the numbers of the two areas connected by the edge respectively, c _nbian,4 is the branch number corresponding to the edge, c _nbian,5 , c _nbian,6 is the node number at both ends of the branch corresponding to the edge, that is, the boundary node of the area;

Step 1-7: Search the nodes d ₁ and d ₂ at both ends of the branch corresponding to the edge, find the areas to which the nodes d ₁ and d ₂ respectively belong, mark the branch, and at the same time set the branch number, node number, and area The number and the number of the area edge are saved in the area adjacency matrix C;

Steps 1-8: Repeat steps 1-7 until all branches are marked, and find the relationship between each area.

4. The network structure simplification processing method of distribution network reconfiguration according to claim 1, characterized in that: in said step 2, a topology reconfiguration strategy is generated by using the adjacency relationship between regions, and according to the The corresponding relationship of the topology reconstruction strategy is restored, and the simplified model of the power flow is used to simplify the restored network structure.

5. The network structure simplification processing method of distribution network reconfiguration according to claim 3, characterized in that: said step 2 specifically comprises the following steps:

Step 2-1: According to the adjacency relationship between regions, the artificial intelligence method is used to reconstruct the simplified topology structure and generate a topology reconstruction strategy;

Step 2-2: According to the radial structure of the distribution network and the characteristics of single power supply, judge whether the generated topology reconfiguration strategy has an island or a ring network, and if so, return to step 2-1 and regenerate the topology reconfiguration strategy; otherwise, execute Step 2-3;

Step 2-3: Using the corresponding relationship between regions and nodes, restore the topology reconstructed through the topology reconstruction strategy;

Step 2-4: Use the power flow simplified model to simplify the restored network structure.

6. The network structure simplification processing method of distribution network reconfiguration according to claim 5, characterized in that: in the step 2-3, the connection relationship between each area is determined according to the generated topology reconfiguration strategy, and then the area is passed through the area The adjacency matrix C finds the corresponding nodes and branches, combined with the internal network structure of Z ₁ , Z ₂ , ..., Z _l , ..., Z _nzone , the entire distribution network network structure can be obtained, and the topology reconstruction is completed Restoration of the policy-refactored topology.

7. The network structure simplified processing method of distribution network reconfiguration according to claim 5, characterized in that: in the simplified power flow model of the step 2-4, for any feeder section containing a plurality of branches, when the power flow When the direction is from the head-end node A of the feeder section to the tail-end node B, the phase voltage drop between the head-end node A and the tail-end node B is used Indicates that there are:

Δ Δ {\overset{\cdot &Center Dot;}{U u}}_{A A B B} = = {Σ Σ}_{i i = = 11}^{N N} {L L}_{i i} ((r r + + j j x x)) {((\frac{{Σ Σ}_{t t = = i i}^{N N} {\overset{\cdot &Center Dot;}{S S}}_{t t}}{{\overset{\cdot &Center Dot;}{U u}}_{A A}}))}^{* *} - - - - - - ((66))

Among them, N is the number of nodes on the feeder segment, L _i is the length of the i-th branch, is the phase voltage of the head-end node A on the feeder section, is the complex power of node t, and the symbol * represents the conjugate;

Let the total length of the feeder section be L, assuming that the feeder section is a uniform conductor, and r and x respectively represent the resistance and reactance per unit length of the feeder section, then the phase voltage drop from node A at the head end to the equivalent node D And the phase voltage drop from the equivalent node D to the end node B Respectively expressed as:

Δ Δ {\overset{\cdot &Center Dot;}{U u}}_{A A D D.} = = {L L}_{A A D D.} ((r r + + j j x x)) {((\frac{{\overset{\cdot &Center Dot;}{S S}}_{D D.}}{{\overset{\cdot &Center Dot;}{U u}}_{A A}}))}^{* *} - - - - - - ((77))

Δ Δ {\overset{\cdot &Center Dot;}{U u}}_{D D. B B} = = 00 - - - - - - ((88))

in, is the complex power of the equivalent node D, and L _AD is the branch length from the headend node A to the equivalent node D;

Combining formulas (6)-(8) can get:

{Σ Σ}_{i i = = 11}^{N N} {L L}_{i i} {((\frac{{Σ Σ}_{t t = = i i}^{N N} {\overset{\cdot &Center Dot;}{S S}}_{t t}}{{\overset{\cdot &Center Dot;}{U u}}_{A A}}))}^{* *} = = {((\frac{{\overset{\cdot \cdot}{S S}}_{D D.}}{{\overset{\cdot &Center Dot;}{U u}}_{A A}}))}^{* *} {L L}_{A A D D.} - - - - - - ((99))

When the power flow direction is from the end node B on the feeder section to the head end node A, there are:

{Σ Σ}_{i i = = 11}^{N N} {L L}_{i i + + 11} {((\frac{{Σ Σ}_{t t = = 11}^{i i} {\overset{\cdot &Center Dot;}{S S}}_{t t}}{{\overset{\cdot &Center Dot;}{U u}}_{B B}}))}^{* *} = = {((\frac{{\overset{\cdot &Center Dot;}{S S}}_{D D.}}{{\overset{\cdot &Center Dot;}{U u}}_{B B}}))}^{* *} {L L}_{D D. B B} - - - - - - ((1010))

in, is the phase voltage of the end node B on the feeder section, L _DB is the branch length from the equivalent node D to the end node B, L _i+1 is the length of the i+1th branch;

Since L _AD +L _DB = L, we can get:

{\overset{\cdot &Center Dot;}{S S}}_{D D.} = = \frac{11}{L L} [[{Σ Σ}_{i i = = 11}^{N N} {L L}_{i i} {Σ Σ}_{t t = = i i}^{N N} {\overset{\cdot &Center Dot;}{S S}}_{t t} + + {Σ Σ}_{t t = = 11}^{N N} {L L}_{i i + + 11} {Σ Σ}_{t t = = 11}^{i i} {\overset{\cdot &Center Dot;}{S S}}_{t t}]] = = {Σ Σ}_{t t = = 11}^{N N} {\overset{\cdot &Center Dot;}{S S}}_{t t} - - - - - - ((1111))

{L L}_{A A D D.} = = \frac{{Σ Σ}_{i i = = 11}^{N N} {L L}_{i i} {Σ Σ}_{t t = = i i}^{N N} {\overset{\cdot &Center Dot;}{S S}}_{t t}}{{Σ Σ}_{t t = = 11}^{N N} {\overset{\cdot \cdot}{S S}}_{t t}} - - - - - - ((1212))

{L L}_{D D. B B} = = \frac{{Σ Σ}_{i i = = 11}^{N N} {L L}_{i i + + 11} {Σ Σ}_{t t = = 11}^{i i} {\overset{\cdot \cdot}{S S}}_{t t}}{{Σ Σ}_{t t = = 11}^{N N} {\overset{\cdot \cdot}{S S}}_{t t}} - - - - - - ((1313)) . .

8. The network structure simplification processing method of distribution network reconfiguration according to claim 7, characterized in that: said step 3 specifically comprises the following steps:

Step 3-1: Carry out forward push-back generation power flow simplification calculation on the restored and simplified network structure, and calculate the reconstruction index according to the power flow analysis results;

Step 3-2: Compare and analyze each topology reconstruction strategy according to the reconstruction index, and judge whether the network structure corresponding to the topology reconstruction strategy is the optimal network structure that satisfies the reconstruction conditions, and if so, select the network structure as the optimal network structure , and output the network structure and reconstruction index at the same time; otherwise, return to step 2-1 to regenerate the topology reconstruction strategy.

9. The network structure simplification processing method for distribution network reconfiguration according to claim 8, characterized in that: said step 3-1 specifically comprises the following steps:

Step 3-1-1: Carry forward and back the simplified calculation of power flow for the restored and simplified network structure, and obtain the A-phase voltage of the head-end node of the feeder section in the simplified model of power flow Phase voltage of terminal node B and the phase voltage at the equivalent node D

Step 3-1-2: Put with As a known quantity, perform a simplified calculation of the power flow on the network structure, recursively push forward from the end node of the network structure, and judge whether the node to be requested belongs to a T node. If the node to be requested does not belong to a T node, perform step 3-1 -3, if the node to be requested belongs to the T contact, then perform step 3-1-4;

Step 3-1-3: When the node to be requested does not belong to the T contact, calculate the branch loss of the tail node k which is expressed as:

{\overset{\cdot \cdot}{S S}}_{L L,, k k} = = ((r r + + j j x x)) {L L}_{k k} | | {((\frac{{\overset{\cdot &Center Dot;}{S S}}_{P P,, k k}}{{\overset{\cdot &Center Dot;}{U u}}_{k k}}))}^{* *} {| |}^{22} - - - - - - ((1414))

Among them, L _k is the branch length of the end node k, is the phase voltage at the end node k, is the total power flowing through the end node k, P represents the total power, and L represents the loss;

Then, the total power flowing through node k-1 Expressed as:

{\overset{\cdot &Center Dot;}{S S}}_{P P,, k k - - 11} = = {\overset{\cdot \cdot}{S S}}_{L L,, k k} + + {\overset{\cdot &Center Dot;}{S S}}_{P P,, k k} + + {\overset{\cdot &Center Dot;}{S S}}_{k k - - 11} - - - - - - ((1515))

in, is the complex power of node k-1;

Phase voltage at node k-1 Expressed as:

{\overset{\cdot \cdot}{U u}}_{k k - - 11} = = {\overset{\cdot &Center Dot;}{U u}}_{k k} + + ((r r + + j j x x)) {L L}_{k k} {((\frac{{\overset{\cdot &Center Dot;}{S S}}_{P P,, k k}}{{\overset{\cdot &Center Dot;}{U u}}_{k k}}))}^{* *} - - - - - - ((1616))

Step 3-1-4: When the node to be requested belongs to the T junction, since the recursion is performed in the reverse direction of the power flow direction, the nodes and branches on the adjacent feeder segment downstream of the tail node k are known, and the calculation flows through the tail The total power of node k have:

{\overset{\cdot &Center Dot;}{S S}}_{P P,, k k} = = \underset{v v &Element; &Element; θ θ}{Σ Σ} (({\overset{\cdot &Center Dot;}{S S}}_{L L,, k k v v} + + {\overset{\cdot &Center Dot;}{S S}}_{P P,, k k v v})) + + {\overset{\cdot &Center Dot;}{S S}}_{k k} - - - - - - ((1717))

Among them, θ is the set of all adjacent feeder segments downstream of the tail end node k according to the power flow direction; v represents all adjacent feeder line segments downstream of the tail end node k according to the power flow direction; is the branch loss on the v-th downstream feeder adjacent to node k, where L represents the loss, and kv is the v-th downstream feeder segment adjacent to the end node k; The total power passing through the tail end node of the downstream feeder end adjacent to node k, P represents the total power; is the complex power of node k;

Step 3-1-5: Calculate the total loss of the network structure, there are:

{\overset{\cdot &Center Dot;}{S S}}_{L L} = = \underset{w w &Element; &Element; λ λ}{Σ Σ} {\overset{\cdot &Center Dot;}{S S}}_{L L,, w w} - - - - - - ((1818))

in, is the total loss of the network structure, is the loss of feeder section w, λ is the set of all feeder sections, and w is the feeder section belonging to the set λ.