CN105787818A - Regional power grid reconstruction method taking supply region constraints into consideration - Google Patents

Abstract

A regional power grid reconstruction method taking supply region constraints into consideration is disclosed. A supply region is a power supply network formed by all substations powered by a 500kV substation, loads and connecting lines thereof, and the supply region constraints are constrained condition set, of the supply region, including a disjoint set M, a dependence set R, a designation set C and an open set O, wherein the disjoint set M contains all substations and devices pairs that can not be in a same supply region, the dependence set R contains all substations and devices pairs that has to be in a same supply region, the designation set C assigns the substations or devices that has to be powered by the designate 500kV substation, and the open set O contains all substations or devices that can be assigned to any other power supply regions. The regional power grid reconstruction method includes the steps of randomly generating a primitive solution space, screening the primitive solution space with the constraints to obtain a new solution space, and searching the optimal solution with an enumeration method.

Description

A kind of area power grid reconstructing method considered for district's constraint

Technical field

The present invention relates to a kind of area power grid reconstructing method considered for district's constraint, belong to a kind of and reduce grid loss, optimize electric network swim, improve the analysis method of power supply reliability.

Background technology

Along with economic quick growth, electrical network scale constantly expands, and power load constantly rises, and the requirement of the safety of electrical network, economical operation and the quality of power supply is more and more higher.How reducing network loss, optimize system load flow, improving system reliability is a long-term job.Improve the safety of operation of power networks, economy method a lot, as existing a kind of by adjusting the method that reactive compensation capacity reduces network loss, but how to utilize existing network equipment resource, by optimizing grid structure, promote operation of power networks economy, strengthen the important topic that its vigorousness is power grid security defence.

Network reconfiguration refers under the premise meeting load needs, by changing the combinations of states of switch tool, reduces network loss, eliminates overload, improve the purposes such as system reliability.Play power transmission network self potentiality by network reconfiguration to improve system reliability, reduce short circuit current, optimize system load flow, eliminate For Congestion, discharge generating capacity, reduce the purposes such as Custom interruption cost.In prior art, it is thus proposed that a kind of back bone network reconstruction strategy evaluated based on pitch point importance, this strategy adopts the importance of power supply and load in the network cohesion degree quantitative assessment network after node contraction.On this basis, with in conjunction with the comprehensive evaluation index of network structure and running quality--network reconfiguration efficiency is come comprehensively, is weighed quality reconstruction objectively.Network reconfiguration problem is the combinatorial optimization problem of a multivariate, non-linear, multiple constraint, and traditional optimized algorithm such as linear programming etc. is helpless to this.The various intelligent optimization algorithms of rising in recent years are widely adopted the network reconfiguration problem solving different target and constraints, such as particle cluster algorithm, genetic algorithm, ant group algorithm etc..These algorithms are simple, it is possible to searching out suboptimal solution in certain precision, but these random heuritic approaches lack corresponding theories integration, perform result and depend on computing environment, twice execution of same problem is likely to be obtained different results.These algorithms are in solution procedure, it does not have utilize the rational experience of management and running personnel as guideline or constraints so that result of calculation deviates from mutually with actual motion condition, have impact on the practicality of algorithm.

Summary of the invention

It is an object of the invention to the deficiency overcoming prior art to exist, and provide a kind of by network reconfiguration performance power transmission network self potentiality, improve system reliability, reduction short circuit current, optimize system load flow, eliminate For Congestion, discharge generating capacity, reduce the consideration area power grid reconstructing method for district's constraint of Custom interruption cost.

It is an object of the invention to complete by following technical solution, a kind of area power grid reconstructing method considered for district's constraint, described it is, for district, all transformer stations and load powered by same 500kV transformer station and supply network that connecting line is constituted, described confession district constraint refers to that what be made up of mutually exclusive sets M, Dependency Set R, set of conventions C, open set O supplies district's constraints set, contains all transformer stations that can not be in same confession district or equipment group pair in described mutually exclusive sets M；Dependency Set R contains all transformer stations that necessarily be in same power supply zone or equipment group pair；Which station set of conventions C specifies or equipment must by the 500kV station power supply specified；The transformer station comprised in open set O or equipment can be assigned in any power supply zone；Traffic control personnel can specify the element of these set voluntarily according to operating experience so that system is run and met requirement；

Described area power grid reconstructing method comprises the steps:

(1) stochastic generation primitive solution space；

(2) screen primitive solution space by constraints, obtain new solution space；

(3) owing to new solution space is substantially reduced than old solution space scale, it is possible to search for optimal solution therein by enumerative technique.

As preferably: in described confession district's constraints set, have at least: device A and B form entry and belong to mutual exclusion set M, are designated as<A, B>∈ M, represent that A and B can not run on a Ge Gong district；In like manner<A, B>∈ R represents that A equipment must run on B device place for district, and<A, 500kV1>∈ C represents that device A must run on in district 500kV1；The operating experience of oneself can be listed and store as the constraints optimized using the form of set for computer reading parsing by operations staff；Tri-set of described M, R, C are rule of thumb formulated voluntarily by operations staff, can arrange constraints flexibly by changing the element in set and not revise any algorithm.

As preferably: described constraints also includes line fault probability, the particularity of the plant stand mode of connection and equipment running status requirement, and makes according to described constraints: when circuit probability of malfunction is higher, avoid this circuit load carrying as far as possible；Due to automatic throw-in equipment of emergency power supply wiring imperfection, circuit can only be adopted for mode；Owing to when there is plug-in strip operation, frequent bite causes the problem that can not draw away or do not close, the equipment such as the switch that should avoid as far as possible operating on this interval.

As preferably: described increase is for after district's constraints, traditional confession district constraints being improved safety with the minimum network reconfiguration for target of year running wastage by increase, the security reliability that is maintained with realizing dropping damage does not reduce, and available equation below represents:

${\mathrm{min\&Delta;W}}_L=\underset{0}{\overset{t}{\&Integral;}}{\mathrm{\&Delta;P}}_L\left(K\right)dt={\mathrm{\&Delta;P}}_L\left(K\right)\mathrm{\&tau;}$

Constraints:

V_min< V_i(K) < V_max

F (M, K)=true

F (R, K)=true

F (C, K)=true

Δ W in formula_LRepresent electric network active year loss of electricity, Δ P_L(K) representing active power loss, it is the function that system can optimize switch vector K,It is a vector,τ is peak load year loss hourage；V_i(K) voltage of each bus of system under respective switch state is represented.V_minFor the minimum voltage that system allows, V_maxFor the ceiling voltage that system allows；F (M, K) function returns whether system under current switch states meets the requirement of mutually exclusive sets, and in like manner, F (R, K) and F (C, K) represents that the device relationships in Dependency Set and set of conventions is no respectively and is satisfied.

Consider that the network reconfiguration for distinguishing analysis can utilize the accumulative operating experience of management and running personnel, run by dynamically adjusting the network optimization realizing under different target for district's constraints.Although supplying the feasible solution needs of district's constraints to carry out repeatedly network topology for finding to meet, but owing to Network topology to reduce a lot than the CPU time of the calculating process consumption such as state estimation, Load flow calculation or continuous tide calculating, management and running experience is taken into account with the form of constraints, considerably reduce last optimizing space, total efficiency is made still to be higher than traditional algorithm, this algorithm is with its efficient quick performance, it will be used widely in on-line analysis system.Meanwhile, adopt this algorithm can effectively reduce total system network loss, make the distribution of branch road load more balanced, improve economy and the safety of operation of power networks effectively.

Accompanying drawing explanation

Fig. 1 is that certain system network architecture of the present invention is for district's distribution schematic diagram.

Fig. 2 is of the present invention for distinguishing analysis schematic diagram.

Flow chart is analysed in the differentiation that supplies that Fig. 3 is the present invention.

Fig. 4 is the reconfiguration of electric networks flow chart based on the constraint of confession district of the present invention.

Detailed description of the invention

The present invention will be described in detail below in conjunction with the accompanying drawings and the specific embodiments: a kind of area power grid reconstructing method considered for district's constraint of the present invention, described it is, for district, all transformer stations and load powered by same 500kV transformer station and supply network that connecting line is constituted, described confession district constraint refers to that what be made up of mutually exclusive sets M, Dependency Set R, set of conventions C, open set O supplies district's constraints set, it is characterised in that contain all transformer stations that can not be in same confession district or equipment group pair in described mutually exclusive sets M；Dependency Set R contains all transformer stations that necessarily be in same power supply zone or equipment group pair；Which station set of conventions C specifies or equipment must by the 500kV station power supply specified；The transformer station comprised in open set O or equipment can be assigned in any power supply zone；Traffic control personnel can specify the element of these set voluntarily according to operating experience so that system is run and met requirement；

Described area power grid reconstructing method comprises the steps:

(1) stochastic generation primitive solution space；

(2) screen primitive solution space by constraints, obtain new solution space；

(3) owing to new solution space is substantially reduced than old solution space scale, it is possible to search for optimal solution therein by enumerative technique.

Of the present invention for, in district's constraints set, having at least: device A and B form entry and belong to mutual exclusion set M, are designated as<A, B>∈ M, represent that A and B can not run on a Ge Gong district；In like manner<A, B>∈ R represents that A equipment must run on B device place for district, and<A, 500kV1>∈ C represents that device A must run on in district 500kV1；The operating experience of oneself can be listed and store as the constraints optimized using the form of set for computer reading parsing by operations staff；Tri-set of described M, R, C are rule of thumb formulated voluntarily by operations staff, can arrange constraints flexibly by changing the element in set and not revise any algorithm.

Constraints of the present invention also includes line fault probability, the particularity of the plant stand mode of connection and equipment running status requirement, and makes according to described constraints: when circuit probability of malfunction is higher, avoid this circuit load carrying as far as possible；Due to automatic throw-in equipment of emergency power supply wiring imperfection, circuit can only be adopted for mode；Owing to when there is plug-in strip operation, frequent bite causes the problem that can not draw away or do not close, the equipment such as the switch that should avoid as far as possible operating on this interval.

Increase of the present invention is for after district's constraints, traditional confession district constraints being improved safety with the minimum network reconfiguration for target of year running wastage by increase, the security reliability that is maintained with realizing dropping damage does not reduce, and available equation below represents:

${\mathrm{min\&Delta;W}}_L=\underset{0}{\overset{t}{\&Integral;}}{\mathrm{\&Delta;P}}_L\left(K\right)dt={\mathrm{\&Delta;P}}_L\left(K\right)\mathrm{\&tau;}$

Constraints:

V_min< V_i(K) < V_max

F (M, K)=true

F (R, K)=true

F (C, K)=true

Δ W in formula_LRepresent electric network active year loss of electricity, Δ P_L(K) representing active power loss, it is the function that system can optimize switch vector K,It is a vector,τ is peak load year loss hourage；V_i(K) voltage of each bus of system under respective switch state is represented.V_minFor the minimum voltage that system allows, V_maxFor the ceiling voltage that system allows；F (M, K) function returns whether system under current switch states meets the requirement of mutually exclusive sets, and in like manner, F (R, K) and F (C, K) represents that the device relationships in Dependency Set and set of conventions is no respectively and is satisfied.

Embodiment:

One, for district's general introduction: area power grid is partition running often in actual motion, with multiple transformer stations and load below a 500kV transformer station.The supply network generally all transformer stations powered by same 500kV transformer station and load and connecting line thereof constituted calls a Ge Gong district, for the title in district with the name nominating of this 500kV transformer station.When one or more 220kV transformer stations are likely to power from two or more 500kV transformer stations simultaneously, now there will be situation about merging for district.It is likely to be connected between transformer station or the load of the lower band in different 500kV stations, it is also possible to being not attached to, what they belonged to can be different along with the change of power system operating mode for district.For district number number, each substation ownership determine, for district, the operation that these transformer stations can carry out, reflect the extent of polymerization of whole electrical network and the redundancy ability of jam-tolerant simultaneously.Adhere to separately and can cause significantly changing of electric network swim when being attached and isolate between the different equipment for district, protective relaying device is adjusted and unit output arrangement produces significant impact.Therefore for economic or safety requirement, or in order to meet the specific needs of power grid operation management, distinct device and belonging to for district of transformer station are had certain requirement by operation maintenance personnel.Fig. 1 illustrates certain system network architecture for district's distribution, and in figure, dotted line represents the interconnector cut-off, and solid line represents the interconnector of input.The independent subregion of Tu1Zhong 500kV transformer station A, 500kV transformer station B, C merge into a power supply zone.220kV station 1 and 220kV station 2 belong to same power supply zone, and 220kV station 6 and 220kV station 4 belong to different power supply zones.Belonging to and allow between the transformer station of same power supply zone to perform some set operations and be unlikely to cause the safety of electrical network that notable change occurs, therefore the ownership of power supply zone is significant for each transformer station.

Two, for district's parser: analysing essence for differentiation is a kind of topological analysis, analyze the Liang Ge transformer station specified or equipment whether in same topology island, and then determine in each of which topology island, there is which 500kV transformer station.It should be noted that must there be two according to two topological islands of operation of power networks experience identification, area and more than two 220kV circuits just can merge into a topological island when being connected, only two topological islands of a 220kV connection are still as two topological islands.The way of equivalence is, first the 220kV bridging line (circuits on uniquely coupled two topological islands) in network is disconnected, then carries out topological analysis.Here " topology island " must have ring, and first radial circuit can be retracted when carrying out bridging line analysis, for distinguishing district's schematic diagram as shown in Figure 2

Fig. 3 show the flow chart supplying to distinguish analysis, and wherein, the switch disconnecting 500kV electric pressure at the beginning is to release the electrical network connection in 500kV side, it is ensured that what topological analysis reflected is the annexation of below 500kV electric pressure.Judging to specify whether plant stand median generatrix allows in same topology island, if bus adheres to multiple different topology island separately in plant stand, then it is indefinite for supplying district belonging to it, should inquire about further with the different main transformers in this plant stand for query object.

Mutually exclusive sets M, Dependency Set R, set of conventions C, open set O can be comprised for district's constraints set.Mutually exclusive sets M contains all transformer stations that can not be in same confession district or equipment group pair；Dependency Set R contains all transformer stations that necessarily be in same power supply zone or equipment group pair；Which station set of conventions C specifies or equipment must by the 500kV station power supply specified；The transformer station comprised in open set O or equipment can be assigned in any power supply zone.Traffic control personnel can specify the element of these set voluntarily according to operating experience so that system is run and met requirement.Assume that device A and B form entry and belong to mutual exclusion set M, be designated as<A, B>∈ M, represent that A and B can not run on a Ge Gong district.In like manner<A, B>∈ R represents that A equipment must run on B device place for district, and<A, 500kV1>∈ C represents that device A must run on in district 500kV1.So the operating experience of oneself can be listed and store as the constraints optimized using the form of set for computer reading parsing by operations staff.Therefore tri-set of M, R, C are rule of thumb formulated voluntarily by operations staff, can arrange constraints flexibly by changing the element in set and not revise any algorithm.

Increase for after district constraints, traditional with the minimum network reconfiguration for target of year running wastage by increase improve safety for district's constraints, the security reliability that is maintained with realizing dropping damage does not reduce, it is possible to use following model representation:

${\mathrm{min\&Delta;W}}_L=\underset{0}{\overset{t}{\&Integral;}}{\mathrm{\&Delta;P}}_L\left(K\right)dt={\mathrm{\&Delta;P}}_L\left(K\right)\mathrm{\&tau;}$

Constraints:

V_min< V_i(K) < V_max

F (M, K)=true

F (R, K)=true

F (C, K)=true

Δ W in formula_LRepresent electric network active year loss of electricity, Δ P_L(K) representing active power loss, it is the function that system can optimize switch vector K,It is a vector,τ is peak load year loss hourage.V_i(K) voltage of each bus of system under respective switch state is represented.V_minFor the minimum voltage that system allows, V_maxFor the ceiling voltage that system allows.F (M, K) function returns whether system under current switch states meets the requirement of mutually exclusive sets, and in like manner, F (R, K) and F (C, K) represents that the device relationships in Dependency Set and set of conventions is no respectively and is satisfied.

Three, consider the network reconfiguration for district's constraint: consider that reconfiguration of electric networks and traditional reconfiguration of electric networks for district's constraint are substantially identical in optimization aim, be all in the space of feasible solution, find an optimal solution weighed with specific objective function or suboptimal solution.Consider that the reconfiguration of electric networks for district's constraint by taking into account the operating experience of management and running personnel with the form of constraints, decreases the hunting zone of alternative feasible solution, it is to avoid traditional algorithm search behavior blindly and the shortcoming being trapped in local optimum.Constraints includes line fault probability, the particularity of the plant stand mode of connection and equipment running status and requires.Such as certain line fault probability is higher, thus avoiding this circuit load carrying as far as possible；Certain plant stand, due to automatic throw-in equipment of emergency power supply wiring imperfection, can only adopt circuit for mode；During the operation of certain plug-in strip, frequent bite causes the problem that can not draw away or do not close, thus the equipment etc. such as the switch avoiding as far as possible operating on this interval.The basic step of algorithm is herein in simple terms:

(1) stochastic generation primitive solution space；

(2) screen primitive solution space by constraints, obtain new solution space；

(3) owing to new solution space is substantially reduced than old solution space scale, it is possible to searching for optimal solution therein by enumerative technique, flow process is as shown in Figure 4.

Four, example of calculation:

Consider to provide grid equipment series of optimum strategy for the network reconfiguration of district's constraint in conjunction with the operating experience of dispatcher, damage and optimizing operating mode that balanced line load is target dropping to instruct dispatching of power netwoks personnel to realize.

Table 1 is that certain section carries out the part optimisation strategy that network reconfiguration provides, table 2 be after network reconfiguration section compared to reconstruct before section change in system losses and branch road load equalization index.Optimizing the strategy provided is the constraints considering dispatcher's operating experience, restriction carries out the folding of 110kV network breaker in middle again after can not carrying out the loop of switching action, make reconstructed network more conform to reality, to 110kV network drop damage and load equalization effect obvious.Simultaneously in order to avoid some strategy enlarges markedly loss and the load equalization index of other electric pressure network while reducing 110kV via net loss and load equalization index, in optimization, damage threshold value index drops in set comprehensive, if other electric pressure network loss of causing of certain strategy and load equalization index ascending amount exceed this threshold value, it can be used as bad strategy to reject.This threshold value index is by determining after cross sections repetition test, it is possible to is paying other electric pressure network loss a small amount of and is realizing total system network loss and the maximum effect of load equalization index slippage under cost that load equalization index rises.

It can be seen that adopt this algorithm can effectively reduce total system network loss contrasting from optimum results, make the distribution of branch road load more balanced, thus improving economy and the safety of operation of power networks.

Table 1 network reconfiguration part operation strategy

Tab.1Partofoperationstrategyforreconfiguration

Table 2 network reconfiguration result

Tab.2Resultsofnetworkreconfiguration

Claims (4)

1. consider the area power grid reconstructing method for district's constraint, described be, for district, all transformer stations and load powered by same 500kV transformer station and supply network that connecting line is constituted；Described confession district constraint refers to that what be made up of mutually exclusive sets M, Dependency Set R, set of conventions C, open set O supplies district's constraints set, it is characterised in that contain all transformer stations that can not be in same confession district or equipment group pair in described mutually exclusive sets M；Dependency Set R contains all transformer stations that necessarily be in same power supply zone or equipment group pair；Which station set of conventions C specifies or equipment must by the 500kV station power supply specified；The transformer station comprised in open set O or equipment can be assigned in any power supply zone；Traffic control personnel can specify the element of these set voluntarily according to operating experience so that system is run and met requirement；

Described area power grid reconstructing method comprises the steps:

(1) stochastic generation primitive solution space；

(2) screen primitive solution space by constraints, obtain new solution space；

(3) owing to new solution space is substantially reduced than old solution space scale, it is possible to search for optimal solution therein by enumerative technique.

2. the area power grid reconstructing method considered for district's constraint according to claim 1, it is characterized in that, in described confession district's constraints set, having at least: device A and B form entry and belong to mutual exclusion set M, are designated as<A, B>∈ M, represents that A and B can not run on a Ge Gong district；In like manner<A, B>∈ R represents that A equipment must run on B device place for district, and<A, 500kV1>∈ C represents that device A must run on in district 500kV1；The operating experience of oneself can be listed and store as the constraints optimized using the form of set for computer reading parsing by operations staff；Tri-set of described M, R, C are rule of thumb formulated voluntarily by operations staff, can arrange constraints flexibly by changing the element in set and not revise any algorithm.

3. the area power grid reconstructing method considered for district's constraint according to claim 1 and 2, it is characterized in that described increase is for after district's constraints, traditional confession district constraints being improved safety with the minimum network reconfiguration for target of year running wastage by increase, the security reliability that is maintained with realizing dropping damage does not reduce, and available equation below represents:

${\mathrm{min\&Delta;W}}_L=\underset{0}{\overset{t}{\&Integral;}}{\mathrm{\&Delta;P}}_L\left(K\right)dt={\mathrm{\&Delta;P}}_L\left(K\right)\mathrm{\&tau;}$

Constraints:

V_min< V_i(K) < V_max

F (M, K)=true

F (R, K)=true

F (C, K)=true

Δ W in formula_LRepresent electric network active year loss of electricity, Δ P_L(K) representing active power loss, it is the function that system can optimize switch vector K, K=[a₁,a₂,a₃,Λ,a_n] it is a vector,τ is peak load year loss hourage；V_i(K) voltage of each bus of system under respective switch state is represented.V_minFor the minimum voltage that system allows, V_maxFor the ceiling voltage that system allows；F (M, K) function returns whether system under current switch states meets the requirement of mutually exclusive sets, and in like manner, F (R, K) and F (C, K) represents that the device relationships in Dependency Set and set of conventions is no respectively and is satisfied.

4. the area power grid reconstructing method considered for district's constraint according to claim 1, it is characterized in that described constraints also includes line fault probability, the particularity of the plant stand mode of connection and equipment running status requirement, and may be made that according to described constraints: when circuit probability of malfunction is higher, avoid this circuit load carrying as far as possible；Due to automatic throw-in equipment of emergency power supply wiring imperfection, circuit can only be adopted for mode；Owing to when there is plug-in strip operation, frequent bite causes the problem that can not draw away or do not close, should avoid as far as possible operating the switchgear on this interval.