CN102868161B - Optimization method of network variable structure with distributed type power supply distribution system - Google Patents
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Abstract
The invention discloses an optimization method of a network variable structure with a distributed type power supply distribution system. The optimization method includes that basic static data of electric power network structure parameters, distributed type power supply distribution, idle resource distribution, load capacity, faulty lines and the like are extracted, building a single power electric betweenness index and a comprehensive island partitioning model and a solving algorithm containing interruptible load; aiming at the partitioned island, proposing survivable static state and dynamic state indexes, and performing assessment and amending; extracting residue structure data after the final island partition, carrying out reconstitution optimization calculation to the residue network by using an ant colony algorithm, and obtaining the optimization structure of the final power grid reconstitution. Through the inventive technology, the partition and reconstruction of the network with the generalized model distributed type power supply distribution system are achieved, and accurate reference of network structure adjustment, schedule and operation can be excellently provided for regional electric power network schedule staffs.
Description
Technical Field
The invention relates to a method and a system for optimizing a network variable structure of a power distribution system with a generalized model and a distributed power supply, and belongs to the field of power grid dispatching operation technology and optimization.
Background
The power distribution system is a variable structure dissipation network, and when a fault occurs, the power distribution system actively splits and adjusts a power transmission path by reasonably changing the on-off state of a switch on a line so as to optimize the operation of the system; the network reconstruction is a safety countermeasure aiming at system weak links, the research of an algorithm is emphasized for a long time, a heuristic rule is constructed by providing a path optimal optimization method, and the optimal scheme of a switch combination is searched; the network division and reconstruction of the power distribution system with the distributed power supply are scientifically realized under the network fault, so that the emergency capacity and the local supply capacity of the distributed power supply are fully exerted under the condition of excavating weak elements and links of the network, the partitioned operation of the power grid is realized, and the significance for the flexible scheduling operation of the power grid is realized; in the environment of encouraging clean energy use and promoting smart grid construction in the whole country, the statistical and analytical work of the operation condition of the relay protection equipment needs to be particularly emphasized, however, the reconstruction of a pure power distribution system is emphasized in the conventional method, the algorithm research is emphasized when the reconstruction of the power distribution system partially combined to a distributed power supply is emphasized, and the island division process and the load interruptability of the distributed power supply are not considered, so that the network loss of a final reconstruction scheme is large or the resource utilization rate is low; in the existing scheduling operation mode method, the consideration of the supporting capability of the distributed power supply and weak links of a network structure of the distributed power supply is lacked; therefore, how to establish a power distribution system reconstruction scheme considering factors such as a power grid operation mode, load importance, distributed power supply supporting capacity, network structure importance, resource utilization rate and the like, more scientifically evaluate a network structure from multiple dimensions, and propose a control decision scheme based on multi-stage calculation correction and survivability evaluation under a fault condition to make an important subject which is continuously solved by technical personnel in the industry.
Disclosure of Invention
The invention aims to provide a method for optimizing a variable structure of a power distribution system network with a distributed power supply, which realizes the division and reconstruction of the power distribution system network with the distributed power supply under the condition of a fault.
In order to achieve the above object, the present invention provides a method for optimizing a variable network structure of a power distribution system including distributed power sources, comprising the steps of:
the method comprises the steps of extracting basic static data such as power grid structure parameters, Distributed Generation (DG) distribution, reactive resource distribution, load size and fault lines, establishing an integrated island division model and solving an algorithm;
(2) aiming at the divided island, providing survivability static and dynamic indexes, and carrying out evaluation and correction;
(3) and extracting the residual network structure data after the final island division, and performing reconstruction optimization calculation on the residual network by using an ant colony algorithm to obtain a final power grid reconstruction optimization structure.
The power grid structure parameters comprise: the nodes refer to connection points among the simplified lines of the power grid, branch connection relations, switch closing states and distributed power supply grid-connected positions; the load parameters include: the load value weight comprises artificial importance level weight of each node and structural weight of each node expressed by single power supply electric medium index.
The mathematical model and the calculation steps of the single power supply electrical permittivity index are as follows:
the method comprises the steps of finding out the number of shortest paths between the nodes of the current distributed power supply and each load node according to a Dijkstra algorithm;
secondly, the number of the shortest paths between the current distributed power supply nodes and the load nodes passing through the nodes to be solved is found out respectively;
thirdly, counting corresponding times, wherein the corresponding times refer to nodeskAnd shortest path passing node between distributed power nodesiThe number of times of the node to be solved is calculated as the sum of the ratio of the corresponding times to the number of the nodes to be solved:
wherein,kin order to be the load node,N k representing nodeskAnd the number of shortest paths between the distributed power nodes,N k i（）representing nodeskAnd shortest path passing node between distributed power nodesiNumber of nodes, shortest path passing nodekThe branch impedance to the distributed power node is sized, with smaller values indicating shorter paths.
The method comprises the following main steps of establishing a comprehensive island division model and solving an algorithm model:
taking out a distributed power supply with the maximum power in a power distribution system under the condition of a fault, taking the distributed power supply as a root node, and setting the output of other distributed power supplies to be 0;
the method comprises the following steps of establishing a mixed integer programming model by aiming at the maximum load value in the divided island without network loss, and calculating by adopting a hidden enumeration method:
wherein,P DGfor the active capacity of the Distributed Generation (DG),Nas to the number of nodes of the system,Mthe number of the branch lines of the system is, H the method is an incidence matrix formed by father-son nodes of each branch of the power distribution system according to the structural parameters of the power grid, the father node and the son nodes are respectively the head end and the tail end of two nodes which are directly connected along the current direction, X is a 0-1 state variable matrix of whether a node is in an island,x i =1 represents a nodeiIs cut into a certain island of the island,x i =0 denotes a nodeiIs not scribed into a certain island of the island,P Lis the sum of island active loads;U i is a nodeiThe voltage is applied to the surface of the substrate,U j is a nodejThe voltage is applied to the surface of the substrate,c i for the node value, the artificial importance level and the node importance degree are respectively reflected, and the definition is as follows:
wherein,a i reflecting nodesiThe load grade can be divided into three grades according to the power failure loss, wherein part of the second-grade and third-grade loads are interruptible loadsThe load is specifically determined by a network and an actual regulation and control policy;b i is a nodeiThe single power supply electrical medium index of (1);
thirdly, calculating according to a mixed integer programming model to obtain an initial island division scheme, then combining a plurality of islands connected by only one branch, calculating network loss to perform load flow calculation, and taking step length to correct interruptible load capacity until the conditions are met:
wherein:is a nodeiThe active power and the reactive power of the power generation,is a nodeiThe active and reactive requirements of the system are,is a nodeiEach DG access node is equipped with reactive compensation resources,G ij in order to make the branch conductance electrically conductive,B ij the power susceptance of the branch is adopted,θ ij is a nodeiAnd nodejThe phase angle difference of the voltage is obtained,mis an AND nodeiThe number of associated branches is then determined,P G 、P S respectively calculating the sum of DG active power output of a certain island and the network loss of the island after load flow calculation, and then determining the reactive power value to be supplemented to a reactive power compensation point according to the load flow calculation;
establishing survivability indexes (static and dynamic), and checking and correcting the formed island;
fifthly, after each pair of distributed power supplies are subjected to islanding calculation, the divided islanding is equivalent to a node without requirement, and then the second largest power distributed power supply is selected to be subjected to islanding calculation until a final islanding scheme is determined.
The survivability static index and evaluation mainly comprise the following aspects:
a. for a single island system, establishing a static voltage stability index:
wherein:I j is a nodejThe static voltage stability index of the voltage-controlled rectifier,andare respectively a branchijThe resistance and the reactance of (a) is,P j 、Q j are respectively nodesjActive and reactive injected power of; get in each nodeIThe largest index is taken as a static voltage stability index of the island system, namely:
according toIAnd the distance between the node and the critical value 1.0 is used for judging the stability degree of the static voltage of the node:Icloser to 0 indicates more stable system, closer to 1.0 indicates more unstable system;
b. and (3) limiting the upper and lower voltage limits:
wherein,U l andU u are respectively asU i The upper and lower limit values of (c),
c. and (3) restricting upper and lower limits of branch tide:
wherein,L l andL u are respectively asL ij The upper and lower limit values of (c),
d. and (3) restricting upper and lower limits of phase angle difference:
wherein,θ l andθ u are respectively asθ i The upper and lower limit values of (c),
e. and (3) constraint of upper and lower limits of static frequency offset:
wherein:andare respectively asfThe upper and lower limit values of (c),the difference value between the output and the requirement of the island system, GD is a certain island node set,is active for islandThe sum of the loads is calculated,is as followsiThe difference-adjusting coefficient of each power supply,for the load adjustment coefficient, the difference between the load type and the different power combining systems will affect the ability of the system to ultimately withstand the static frequency offset.
The dynamic indicators and assessments of survivability are:
considering dynamic models of the internal components of an island, for an island System including a Wide Area Monitoring System (WAMS) System, the island System is provided withnThe unbalanced power in the isolated network of the platform generator is as follows:
wherein,T j is the time constant of inertia of the generator, is the power angle of the generator and is,ω N is a rated angular velocity; setting upP LD For unbalanced power margin, then:
when in useΔP>P LD When the system is unstable in the future time, the load must be immediately reduced to eliminate unbalanced power generated by faults;
when in useΔP<P LD When the system is disturbed, the system will gradually recover to be stable in a future running track, and the load shedding measure at the moment fully considers the local voltage stability margin of the system caused by the disturbance and increases the damping to enable the system to recover a new stable running point as soon as possible;
the index is used as the basis for load shedding, volume fixing and site selection; wherein,X ij is a branchijThe reactance of,Z ij Is a branchijThe impedance of,Is a nodejThe reactive injection power of,Is a nodeiVoltage of (d);FVSI ij the closer to 1, the more unstable the line is, the more easily the voltage breakdown of the node is caused; defining dynamic voltage stability indexWhere λ is the weight of each line,Jis an AND nodeiA set of directly connected nodes is formed,Mis the total number of lines; of circuitsFVSI ij The closer the value is to 1, the greater the weight lambda is, so as to find out the load node with the most outstanding line voltage stability problem as a load shedding place, and adopt a corresponding load shedding control strategy.
The load shedding control strategy comprises the following steps:
the method includes the steps that measurement data provided by a wide area monitoring system are utilized to predict power angle running tracks of all generators in the system;
secondly, quantifying initial unbalanced power of the system caused by faults by combining the predicted value of the previous step;
the stability index of the voltage according to the dynamic stateV Di Determining the order of load shedding points, nodesiLoad shedding amount ofPS i Comprises the following steps:
。
the residual network reconstruction optimization calculation is to arrange and divide the nodes after the island and the data of the connection relation between the nodes, and the step of performing optimization calculation by adopting an ant colony algorithm with the minimum network loss as a target is as follows:
coding switch states, wherein all the states in each time period form a path;
first, in a cycle, there ismOnly ants participate in the path-findingkBy nodeiTransfer to nodejThe probability of (c) is:
wherein,respectively information concentration and relative importance factors of heuristic information,to representtTime of day pathijThe concentration of the pheromone on the surface,representing slave nodesiTransfer to nodejThe heuristic information of (a) the user is,taking the reciprocal of the resistance of the branch circuit,namely the antkA set of nodes allowed to access next;
(3) only ants pass throughnHas accessed all the timenAfter each node, the pheromone concentration is updated by calling the following formula:
wherein,is a coefficient of the degree of pheromone residual,，representing antskOn the path in this cycleijThe concentration of pheromone left on the surface of antskPassing through the pathijLet us order，The path is globally optimal in the cycle, namely the path with the minimum system network loss is obtained;
(4) over-iterative computation whenmWhen only ants select the same path or reach the maximum iteration times, an optimization result is obtained, namely the residual network reconstruction scheme is obtained.
The invention has the beneficial effects that:
according to the invention, the final reconstruction scheme and the island evaluation result of the current power distribution system with the distributed power supply are obtained by analyzing and calculating the network structure parameter data of the dispatching operation center, so that the network division and reconstruction of the power distribution system with the distributed power supply are realized, and more accurate network structure adjustment, dispatching and operation references can be better provided for relevant dispatching operation personnel; the island division part fully considers the variable structure characteristics of the network and the flexible load control characteristics, establishes a multistage mathematical model which is formed by taking the maximum load recovery amount, the minimum interruptible load interruption amount and the like as targets and constraints such as static survivability and the like, converts the multistage mathematical model into a satisfiability problem, solves the mixed integer programming problem by adopting a hidden enumeration algorithm, takes account of the variable structure characteristics and the flexible load control characteristics of the network, and solves the mixed integer programming problem by adopting a hidden enumeration algorithmReactive compensation and island correction required by a load flow calculation system are carried out on the network loss, and a most possible and sufficiently good island division scheme is obtained; then dividing the data into static indexes and dynamic indexes according to survivability indexes, wherein the static indexes and the dynamic indexes are mainly evaluated from branch tide indexes, node voltage fluctuation indexes and system voltage stability indexes, and the dynamic indexes fully consider an element dynamic model, are combined with WAMS information to evaluate unbalanced power and are introducedFVSI ij The indexes are used as the basis for load shedding, volume fixing and site selection, and a load control strategy is implemented according to specific conditions; and the rest networks find out the ideal combination of the power supply, the load and the circuit based on the ant colony algorithm, so that the structure optimization of the intelligent power distribution system is realized.
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Fig. 1 is a schematic flow chart of a method for optimizing a variable structure of a power distribution system with distributed power sources according to the present invention.
Detailed Description
The following describes the optimization method of the variable structure of the power distribution system network with distributed power sources in detail with reference to the accompanying drawings and embodiments.
Referring to fig. 1, fig. 1 is a schematic flow chart of a method for optimizing a variable network structure of a distribution system with distributed power sources according to the present invention, which includes the steps of:
the method comprises the steps of extracting basic static data such as power grid structure parameters, Distributed Generation (DG) distribution, reactive resource distribution, load size and fault lines, establishing an integrated island division model and solving an algorithm;
(2) aiming at the divided island, providing survivability static and dynamic indexes, and carrying out evaluation and correction;
(3) and extracting the residual network structure data after the final island division, and performing reconstruction optimization calculation on the residual network by using an ant colony algorithm to obtain a final power grid reconstruction optimization structure.
The power grid structure parameters comprise: the nodes refer to connection points among the simplified lines of the power grid, branch connection relations, switch closing states and distributed power supply grid-connected positions; the load parameters include: the load value weight comprises artificial importance level weight of each node and structural weight of each node expressed by single power supply electric medium index.
The mathematical model and the calculation steps of the single power supply electrical permittivity index are as follows:
the method comprises the steps of finding out the number of shortest paths between the nodes of the current distributed power supply and each load node according to a Dijkstra algorithm;
secondly, the number of the shortest paths between the current distributed power supply nodes and the load nodes passing through the nodes to be solved is found out respectively;
thirdly, counting corresponding times, wherein the corresponding times refer to nodeskAnd shortest path passing node between distributed power nodesiThe number of times of the node to be solved is calculated as the sum of the ratio of the corresponding times to the number of the nodes to be solved:
wherein,kin order to be the load node,N k representing nodeskAnd the number of shortest paths between the distributed power nodes,N k i（）representing nodeskAnd shortest path passing node between distributed power nodesiNumber of nodes, shortest path passing nodekThe branch impedance to the distributed power node is sized, with smaller values indicating shorter paths.
The method comprises the following main steps of establishing a comprehensive island division model and solving an algorithm model:
taking out a distributed power supply with the maximum power in a power distribution system under the condition of a fault, taking the distributed power supply as a root node, and setting the output of other distributed power supplies to be 0;
the method comprises the following steps of establishing a mixed integer programming model by aiming at the maximum load value in the divided island without network loss, and calculating by adopting a hidden enumeration method:
wherein,P DGfor the active capacity of the Distributed Generation (DG),Nas to the number of nodes of the system,Mthe number of the branch lines of the system is, H the method is an incidence matrix formed by father-son nodes of each branch of the power distribution system according to the structural parameters of the power grid, the father node and the son nodes are respectively the head end and the tail end of two nodes which are directly connected along the current direction, X is a 0-1 state variable matrix of whether a node is in an island,x i =1 represents a nodeiIs cut into a certain island of the island,x i =0 denotes a nodeiIs not scribed into a certain island of the island,P Lis the sum of island active loads;U i is a nodeiThe voltage is applied to the surface of the substrate,U j is a nodejA voltage.c i For the node value, the artificial importance level and the node importance degree are respectively reflected, and the definition is as follows:
wherein,a i reflecting nodesiThe load grade can be divided into three grades according to the power failure loss, wherein part of the second-grade load and the third-grade load are interruptible loads and are specifically determined by a network and an actual regulation and control policy;b i is thatNode pointiThe single power supply electrical medium index of (1);
(3) calculating according to a mixed integer programming model to obtain an initial island division scheme, then combining a plurality of islands connected by only one branch, calculating network loss to perform load flow calculation, and taking step length to correct interruptible load capacity until the conditions are met:
wherein:is a nodeiThe active power and the reactive power of the power generation,is a nodeiThe active and reactive requirements of the system are,is a nodeiEach DG access node is equipped with reactive compensation resources,Gijin order to make the branch conductance electrically conductive,Bijthe power susceptance of the branch is adopted,θ ij is a nodeiAnd nodejVoltage phase angle difference;mis an AND nodeiThe number of associated branches is then determined,P G 、P S the sum of DG active power output of a certain island and the island network loss after load flow calculation are respectively obtained; then, determining a reactive value to be supplemented to the reactive compensation point according to load flow calculation;
establishing survivability indexes (static and dynamic), and checking and correcting the formed island;
after carrying out the calculation once (carrying out the island division calculation on each pair of distributed power supplies), equating the divided island to a node without requirement, and selecting the second largest power distributed power supply to carry out the island division calculation; until the final islanding scheme is determined.
The survivability static index and evaluation mainly comprise the following aspects:
a. for a single island system, establishing a static voltage stability index:
wherein:I j is a nodejThe static voltage stability index of the voltage-controlled rectifier,andare respectively a branchijThe resistance and the reactance of (a) is,P j 、Q j are respectively nodesjActive and reactive injected power of; get in each nodeIThe largest index is taken as a static voltage stability index of the island system, namely:
according toIAnd the distance between the node and the critical value 1.0 is used for judging the stability degree of the static voltage of the node:Icloser to 0 indicates more stable system, closer to 1.0 indicates more unstable system;
b. and (3) limiting the upper and lower voltage limits:
wherein,U l andU u are respectively asU i The upper and lower limit values of (c),
c. and (3) restricting upper and lower limits of branch tide:
wherein,L l andL u are respectively asL ij The upper and lower limit values of (c),
d. and (3) restricting upper and lower limits of phase angle difference:
wherein,θ l andθ u are respectively asθ i The upper and lower limit values of (c),
e. and (3) constraint of upper and lower limits of static frequency offset:
wherein:andare respectively asfThe upper and lower limit values of (c),the difference value between the output and the requirement of the island system, GD is a certain island node set,is the sum of the active loads of the island,is as followsiThe difference-adjusting coefficient of each power supply,for the load adjustment coefficient, the difference between the load type and the different power combining systems will affect the ability of the system to ultimately withstand the static frequency offset.
The dynamic indicators and assessments of survivability are:
considering dynamic models of the internal components of an island, for an island System including a Wide Area Monitoring System (WAMS) System, the island System is provided withnThe unbalanced power in the isolated network of the platform generator is as follows:
wherein,T j is the inertia time constant of the generator; is the power angle of the generator;ω N is the nominal angular velocity. Setting upP LD For unbalanced power margin, then:
when in useΔP>P LD When the system is unstable in the future time, the load must be immediately reduced to eliminate unbalanced power generated by faults;
when in useΔP<P LD When the system is disturbed, the system will gradually recover to be stable in a future running track, and the load shedding measure at the moment fully considers the local voltage stability margin of the system caused by the disturbance and increases the damping to enable the system to recover a new stable running point as soon as possible;
the index is used as the basis for load shedding, volume fixing and site selection; wherein,X ij is a branchijThe reactance of,Z ij Is a branchijThe impedance of,Is a nodejThe reactive injection power of,Is a nodeiVoltage of (d);FVSI ij the closer to 1, the more unstable the line is, the more easily the voltage breakdown of the node is caused; defining dynamic voltage stability indexWhere λ is the weight of each line,Jis an AND nodeiA set of directly connected nodes is formed,Mis the total number of lines; of circuitsFVSI ij The closer the value is to 1, the greater the weight lambda is, so as to find out the load node with the most outstanding line voltage stability problem as a load shedding place, and adopt a corresponding load shedding control strategy.
The load shedding control strategy comprises the following steps:
the method includes the steps that measurement data provided by a wide area monitoring system are utilized to predict power angle running tracks of all generators in the system;
(2) quantifying the initial unbalanced power of the system caused by the fault according to the predicted value of the previous step;
the stability index of the voltage according to the dynamic stateV Di Determining the order of load shedding points, nodesiLoad shedding amount ofPS i Comprises the following steps:
。
the residual network reconstruction optimization calculation is to arrange and divide the nodes after the island and the data of the connection relation between the nodes, and the step of performing optimization calculation by adopting an ant colony algorithm with the minimum network loss as a target is as follows:
coding switch states, wherein all the states in each time period form a path;
in one cycle of the medicinemOnly ants participate in the path-findingkBy nodeiTransfer to nodejThe probability of (c) is:
wherein,respectively information concentration and relative importance factors of heuristic information,to representtTime of day pathijThe concentration of the pheromone on the surface,representing slave nodesiTransfer to nodejThe heuristic information of (a) the user is,taking the reciprocal of the resistance of the branch circuit,namely the antkA set of nodes allowed to access next;
(3) only ants pass throughnHas accessed all the timenAfter each node, the pheromone concentration is updated by calling the following formula:
wherein,is a coefficient of the degree of pheromone residual,，indicates the ant k is on the path in the cycleijThe concentration of pheromone left on the surface of antskPassing through the pathijLet us order，The path is globally optimal in the cycle, namely the path with the minimum system network loss is obtained;
performing iterative calculation whenmWhen only ants select the same path or reach the maximum iteration times, an optimization result is obtained, namely the residual network reconstruction scheme is obtained.
Fig. 2 is an effect diagram of performing structure-variable optimization operation after a 70-node branch 1-2, 1-16, 30-70 of the distribution system with the distributed power supply fails.
The above-described embodiments of the present invention do not limit the scope of the present invention. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.
Claims (4)
1. A method for optimizing a variable structure of a power distribution system network with a distributed power supply is characterized by comprising the following steps:
the method includes the steps of extracting five kinds of static data such as power grid structure parameters, distributed power distribution, reactive power resource distribution, load parameters and fault lines;
(2) designing a single-power-supply electrical medium index, establishing a comprehensive island division model and a solution strategy containing survivability static indexes, and determining a final island division scheme;
(3) extracting the residual network structure data after the final island division, and performing reconstruction optimization calculation on the residual network by adopting an ant colony algorithm with the minimum system network loss as a target to obtain a final power grid reconstruction optimization structure;
the mathematical model and the calculation steps of the single power supply electrical dielectric index are as follows:
a. finding out the number of shortest paths between the current distributed power supply node and each load node according to a Dijkstra algorithm, wherein the distributed power supply node refers to a node with distributed power supply access;
b. counting corresponding times, wherein the corresponding times refer to load nodeskAnd shortest path passing node between distributed power nodesiThe sum of the ratio of the corresponding times to the number of the bars is calculated as the nodeiSingle power supply electrical permittivity of (d):
wherein,kin order to be the load node,Tis a set of load nodes, and the load nodes,N k representing load nodeskAnd the number of shortest paths between the distributed power nodes,N k i（）representing load nodeskAnd shortest path passing node between distributed power nodesiNumber of times, length of path through load nodekThe branch impedance to the distributed power node is determined, and the smaller the branch impedance value is, the shorter the path is.
2. The distributed power containing power distribution system network variable structure optimization method of claim 1, wherein the grid structure parameters comprise: node number, branch connection relation and switch closing state; the load parameters include: the load value weight comprises artificial importance level weight of each node and structural weight of each node expressed by single power supply electric medium index.
3. The method for optimizing the variable structure of the power distribution system network with the distributed power sources according to claim 1, wherein the steps of establishing the comprehensive island division model and the solution strategy including the survivability static indexes comprise:
taking out a distributed power supply with the maximum power in a power distribution system under the condition of a fault, taking the distributed power supply as a root node, and setting the output of other distributed power supplies to be 0;
the method comprises the following steps of establishing a mixed integer programming model by aiming at the maximum load value in the divided island without network loss, and calculating by adopting a hidden enumeration method:
wherein,P DGfor the active capacity of the distributed power supply,Nas to the number of nodes of the system,Mthe number of the branch lines of the system is, H the method is an incidence matrix formed by father-son nodes of each branch of the power distribution system according to the structural parameters of the power grid, the father node and the son nodes are respectively the head end and the tail end of two nodes which are directly connected along the current direction, X is a 0-1 state variable matrix of whether a node is in an island,x i =1 represents a nodeiIs cut into a certain island of the island,x i =0 denotes a nodeiIs not scribed into a certain island of the island,P iLis a nodeiThe active load of the station(s),is a nodeiThe amount of load interruption is taken into account,c i for node value, defined as:
wherein,a i reflecting nodesiThe load grade is divided into three grades according to the power failure loss;b i is a nodeiThe single power supply electrical medium index of (1);
thirdly, calculating according to the mixed integer programming model to obtain an initial island division scheme, then combining a plurality of islands connected by only one branch, calculating network loss, performing load flow calculation, and correcting interruptible load capacity until the conditions are met:
wherein:is a nodeiThe amount of load interruption is taken into account,is a nodeiThe active power and the reactive power of the power generation,is a nodeiThe active and reactive requirements of the system are,is a nodeiEach distributed power node is provided with reactive compensation resources,G ij conducting for branch;P Lis the sum of the active loads of the island,U i is a nodeiThe voltage is applied to the surface of the substrate,U j is a nodejThe voltage is applied to the surface of the substrate,B ij the power susceptance of the branch is adopted,θ ij is a nodeiAnd nodejVoltage phase angle difference;mis an AND nodeiThe number of associated branches is then determined,P G 、P S the sum of the active power output of the distributed power supply of an island and the island network loss after load flow calculation are respectively calculated; then, determining a reactive value to be supplemented to the reactive compensation point according to load flow calculation;
(4) establishing a survivability static index, and evaluating and correcting the formed island;
fifthly, after each pair of distributed power supplies are subjected to islanding calculation, the divided islanding is equivalent to a node without requirement, and then the second largest power distributed power supply is selected to be subjected to islanding calculation until a final islanding scheme is determined.
4. The method of claim 1, wherein the survivability static indicators comprise:
a. for a single island system, establishing a static voltage stability index:
wherein:I j is a nodejThe static voltage stability index of the voltage-controlled rectifier,U i is a nodeiThe voltage is applied to the surface of the substrate,andare respectively a branchijThe resistance and the reactance of (a) is,P j 、Q j are respectively nodesjActive and reactive injected power of; get in each nodeIThe largest index is taken as a static voltage stability index of the island system, namely:
；
according toIAnd the distance between the node and the critical value 1.0 is used for judging the stability degree of the static voltage of the node:Icloser to 0 indicates more stable system, closer to 1.0 indicates more unstable system;
b. and (3) limiting the upper and lower voltage limits:
wherein,U l andU u are respectively asU i The upper and lower limit values of (c),
c. and (3) restricting upper and lower limits of branch tide:
wherein,L l andL u are respectively asL ij The upper and lower limit values of (c),
d. and (3) restricting upper and lower limits of phase angle difference:
wherein,θ l andθ u are respectively asθ i The upper and lower limit values of (c),
e. and (3) constraint of upper and lower limits of static frequency offset:
wherein:andare respectively frequencyfThe upper and lower limit values of (c),the difference between the output of the island system and the demand,is frequency offDifference from the nominal value, GD is the island node set,is the sum of the active loads of the island,is as followsiThe difference-adjusting coefficient of each power supply,is the coefficient of the difference between the loads,K s is the equivalent adjustment coefficient of the system.
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101986496A (en) * | 2010-09-29 | 2011-03-16 | 天津大学 | Method for forming islands of distribution system containing distributed power supply |
| CN102290799A (en) * | 2011-08-11 | 2011-12-21 | 中国电力科学研究院 | Small-scale quick recovery method for power supply of power distribution network in open loop running |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102280875A (en) * | 2010-06-13 | 2011-12-14 | 阿海珐T&D英国有限公司 | Island division of power network |
-
2012
- 2012-10-23 CN CN201210406616.XA patent/CN102868161B/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101986496A (en) * | 2010-09-29 | 2011-03-16 | 天津大学 | Method for forming islands of distribution system containing distributed power supply |
| CN102290799A (en) * | 2011-08-11 | 2011-12-21 | 中国电力科学研究院 | Small-scale quick recovery method for power supply of power distribution network in open loop running |
Non-Patent Citations (1)
| Title |
|---|
| 含分布式发电的配电网优化运行研究;赵晶晶;《中国博士学位论文全文数据库》;20111031;第53-54页 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106169773A (en) * | 2016-08-29 | 2016-11-30 | 上海交通大学 | Intelligent distribution network power supply optimization method containing Distributed-generation equipment |
| CN106169773B (en) * | 2016-08-29 | 2020-05-22 | 上海交通大学 | Power supply optimization method for intelligent power distribution network comprising distributed power generation equipment |
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