CN106549376A - The branch road comprehensive stability appraisal procedure of power distribution network containing DG based on equivalent node method - Google Patents
The branch road comprehensive stability appraisal procedure of power distribution network containing DG based on equivalent node method Download PDFInfo
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/04—Circuit arrangements for ac mains or ac distribution networks for connecting networks of the same frequency but supplied from different sources
- H02J3/06—Controlling transfer of power between connected networks; Controlling sharing of load between connected networks
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
- H02J3/381—Dispersed generators
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- H02J3/383—
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- H02J3/386—
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2203/00—Indexing scheme relating to details of circuit arrangements for AC mains or AC distribution networks
- H02J2203/20—Simulating, e g planning, reliability check, modelling or computer assisted design [CAD]
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- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
- Y02E10/56—Power conversion systems, e.g. maximum power point trackers
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/76—Power conversion electric or electronic aspects
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Abstract
The branch road comprehensive stability appraisal procedure of power distribution network containing DG based on equivalent node method, belongs to power distribution network safety and stability evaluation technical field, including by Load flow calculation, obtains power distribution network root node voltage Power Flow Information；The two node generating and transmitting system equivalent models set up on i-node；Set up two node power distribution net branch road m equivalent models；Integration process is carried out to model, equivalent parameterss are calculated；The comprehensive stability coefficient of power distribution network branch road m is calculated according to equivalent parameterss；The comprehensive stability coefficient value and most fragile branch road of power distribution network are obtained according to the comprehensive stability coefficient of all branch roads；The present invention is introduced into generating and transmitting system in object of study, improves the accuracy of the assessment of power distribution network containing DG, and transmission ＆ distribution Cooperative Analysis ensure that economic power system and safe operation；By defining brand-new collapse of voltage coefficient and traffic overload coefficient, the assessment to power distribution network branch voltage stabilizing power and load bearing capacity is realized, assessment is made more comprehensively.
Description
Technical Field
The invention belongs to the technical field of power distribution network safety and stability assessment, and particularly relates to a comprehensive stability assessment method for a branch of a power distribution network containing DGs based on an equivalent node method.
Background
Along with the development of national economy, the load of the power distribution network is increased rapidly, and the load bearing capacity of the power distribution network is closer to the limit state, so that the power distribution system can also have a stability problem. The safe and stable operation of the power distribution network is an important guarantee for improving the power supply reliability and providing good power quality for users. However, as more and more distributed power sources penetrate into the infrastructure of the power distribution system, the power distribution network changes from the original single-power-supply system to a multi-power-supply system with dispersed power sources, which makes the analysis and evaluation of the stability of the power distribution network in new situations a new challenge.
At present, for stability analysis and evaluation of a power distribution network containing a Distributed Generation (DG), domestic and foreign researches mostly analyze the power distribution network independently, only process equivalent power sources on a power transmission and generation system, but do not introduce the power transmission and generation system into a research object sufficiently and effectively, and the situation that the connection between the power transmission and generation system and the power distribution network is increasingly tight is violated, so that the accuracy of the traditional stability analysis and evaluation of the power distribution network containing the distributed generation is not too high. Meanwhile, the traditional single stability evaluation index of the power distribution network cannot clearly reflect the occurrence mechanism of unstable conditions of the power distribution network, such as voltage collapse, overload load and the like.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a comprehensive stability evaluation method for a branch of a DG-containing power distribution network based on an equivalent node method.
The technical scheme of the invention is as follows:
the comprehensive stability evaluation method of the branch of the DG-containing power distribution network based on the equivalent node method comprises the following steps:
step 1: performing combined integrated load flow calculation on the power generation and transmission system and the power distribution network containing the DGs to obtain the voltage load flow information of the root nodes of the power distribution network containing the DGs
Step 1-1: setting a voltage initial value and a convergence standard of a root node of a DG-containing power distribution network;
step 1-2: carrying out load flow calculation of a forward-backward substitution method of the DG-containing power distribution network, and solving an iterative intermediate variable;
step 1-3: according to the iteration intermediate variable, carrying out Newton-Raphson method load flow calculation on the power transmission and transmission system, and solving the voltage value of a root node of the power distribution network containing DG;
step 1-4: calculating the voltage difference of the root node before and after two adjacent iterations, and finishing the power transmission and distribution combined integrated power flow calculation if the convergence standard is met to obtain the power distribution network root node voltage power flow information containing DGIf the convergence criterion is not met, the step 1-2 is executed.
The power generation and transmission system comprises N nodes, wherein a node 1-a node M are generator nodes, a node M + 1-a node N are load nodes, and the root node is a connection node i including a DG power distribution network and the power generation and transmission system, wherein i is M +1, M +2, … and N.
Step 2: simplifying equivalent processing is carried out on the power generation and transmission system, equivalent power supply voltage and equivalent impedance are calculated, and an equivalent model of the two-node power generation and transmission system on the i node is obtained; the specific method is that the following three variables are defined:
then the two-node simplified equivalent model of the N-node-containing power generation and transmission system on the i node is:
wherein G ═ {1, …, M }, L ═ M +1, …, N },is an equivalent two-node moduleA type of equivalent supply voltage;is an equivalent load;equivalent impedance of thevenin, namely equivalent impedance of a two-node model of the power generation and transmission system;is the transfer impedance between the i node and the j node;is an equivalent current of the electric current,is the injected current on the j node,is the voltage of the j-node,the value of which is the load power on node j.
And step 3: the method comprises the following steps of carrying out simplified equivalent processing on a branch m in a distribution network containing DGs, calculating equivalent impedance and voltage difference of two nodes, and obtaining an equivalent model of the branch m of the distribution network containing DGs at the two nodes, wherein the specific method comprises the following steps:
for a DG-containing power distribution network connected to a power generation and transmission system through a step-down transformer, the injection currents of photovoltaic and wind power are set to beThen the branch m of the distribution network containing DG is simplified into the voltage difference between two nodes in the two-node systemComprises the following steps:
wherein,is the equivalent impedance of the transformer;in order to be able to pass the current through the transformer,is the line impedance of j sub-branches in m branches of a DG-containing power distribution network, NmThe number of the sub-branches in the m-branch, nm,jPVThe method comprises the following steps that the number of all photovoltaic power stations on the tail node of a j sub-branch of an m branch of a DG-containing power distribution network is counted; n ism,jWTThe method comprises the steps that the number of all wind power plants on the tail node of a j branch of an m branch of a DG-containing power distribution network is counted;
equivalent impedance of branch m of distribution network containing DGComprises the following steps:
wherein N istotalThe total distributed power supply number in the power distribution network containing the DGs.
And 4, step 4: integrating the equivalent model of the two-node power generation and transmission system and the equivalent model of the two-node branch m of the distribution network containing the DGs, calculating equivalent parameters, namely equivalent impedance, equivalent load node voltage and equivalent load power, and obtaining a model for evaluating and researching the stability of the branch of the distribution network containing the DGs, wherein the specific method for calculating the equivalent parameters comprises the following steps:
calculating equivalent impedance
Calculating equivalent load node voltage
Calculating equivalent load power
Wherein,the total load power of a branch m of the distribution network containing the DGs is obtained;for the total injected photovoltaic power comprising the branches m of the DG distribution network,and (4) injecting power into the total wind power of the branch m of the power distribution network containing the DG.
And 5: calculating the voltage collapse coefficient VDC of branch m in the DG-containing power distribution network according to the equivalent parametersi,m＝Vn,m 2-Vp,m 2Load overload coefficientAnd overall stability factor EDCi,m：
EDCi,m＝VDCi,m+LDCi,m＝Vn,m 2-2Zi,mSi,m
Wherein,Vd-,m 2＝Vsi 2-2Zi,mSef(i,m)；Sef(i,m)＝Si,m(1+cosβi,m)，βi,m＝φi,m-θi,m；φi,mis composed ofAngle of power factor of thetai,mIs an equivalent impedanceThe impedance angle of (c).
Step 6: sequentially calculating comprehensive stability coefficient EDC of all branches in DG-containing power distribution networki,mThe comprehensive stability coefficient value of the DG-containing power distribution network is the minimum value min { EDC) of the comprehensive stability coefficient of each branchi,mAnd the branch with the minimum comprehensive stability coefficient value in the branches of the DG-containing power distribution network is the weakest branch in the DG-containing power distribution network.
Has the advantages that: compared with the prior art, the comprehensive stability evaluation method of the branch of the DG-containing power distribution network based on the equivalent node method has the following advantages:
(1) by sufficiently and effectively introducing the power generation and transmission system into a research object, the accuracy of stability analysis and evaluation of the power distribution network containing the distributed power supply is improved, and meanwhile, the economy and safe operation of the power grid are ensured through transmission and distribution cooperative analysis;
(2) by defining a brand new voltage collapse coefficient and a brand new load overload coefficient, the voltage stability and the load bearing capacity of the branch of the power distribution network with the distributed power supply are evaluated, and therefore the safety and stability conditions of the power distribution network are comprehensively analyzed and evaluated.
Drawings
FIG. 1 is a schematic diagram of an IEEE 5 power generation and transmission system in accordance with an embodiment of the present invention;
FIG. 2 is a schematic diagram of a power distribution network including distributed generation in accordance with an embodiment of the present invention;
fig. 3 is a flowchart of a comprehensive stability evaluation method for a branch of a distribution network including a DG based on an equivalent node method according to an embodiment of the present invention;
fig. 4 is a simplified equivalent model diagram of two nodes of an IEEE 5 power transmission system according to an embodiment of the present invention as seen from node 3;
fig. 5 is an equivalent model diagram of two nodes of a branch of a distribution network including a distributed power supply according to an embodiment of the present invention;
fig. 6 is a model diagram of a branch stability evaluation study of a distribution network including a distributed power supply according to an embodiment of the present invention.
Detailed Description
An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.
In the present embodiment, an example is described in which a node 3 is connected to a distribution network including a Distributed Generation (DG) in an IEEE 5 power transmission system, and as shown in fig. 1, the IEEE 5 power transmission system includes two generator nodes of a node 1 and a node 2 and three load nodes of the node 3, the node 4, and the node 5, and N is 5 nodes in total. A distribution network including DG is shown in fig. 2.
As shown in fig. 3, the comprehensive stability evaluation method for a branch of a distribution network including a DG based on an equivalent node method includes the following steps:
step 1: performing combined integrated load flow calculation on a power generation and transmission system and a power distribution network containing DGs to obtain DG power distribution network root node voltage load flow information
Step 1-1: setting a voltage initial value and a convergence standard of a root node of a DG-containing power distribution network;
step 1-2: carrying out load flow calculation of a forward-backward substitution method of the DG-containing power distribution network, and solving an iterative intermediate variable;
step 1-3: according to the iteration intermediate variable, carrying out Newton-Raphson method load flow calculation on the power transmission and transmission system, and solving the voltage value of a root node of the power distribution network containing DG;
step 1-4: calculating the voltage difference of the root node before and after two adjacent iterations, and finishing the power transmission and distribution combined integrated power flow calculation if the convergence standard is met to obtain the power distribution network root node voltage power flow information containing DGIf the convergence criterion is not met, the step 1-2 is executed.
In the embodiment, after the transmission and distribution combined integrated power flow calculation, the voltage of the root node of the distribution network containing the DG, namely the voltage of the node 3 of the power generation and transmission system is obtained
Step 2: simplifying equivalent processing is carried out on the power generation and transmission system, equivalent power supply voltage and equivalent impedance are calculated, and an equivalent model of the two-node power generation and transmission system on the i node is obtained; the specific method is that the following three variables are defined:
then the two-node simplified equivalent model of the N-node-containing power generation and transmission system on the i node is:
wherein G ═ {1, …, M }, L ═ M +1, …, N },the equivalent power supply voltage is equivalent to the equivalent two-node model;is an equivalent load; equivalent impedanceIs thevenin equivalent impedance;is the transfer impedance between the i node and the j node;is an equivalent current of the electric current,is the injected current on the j node,is the voltage of the j-node,the value of which is the load power on node j.
In the present embodiment, the simplified equivalent model of two nodes of the IEEE 5 power transmission system as viewed from the node 3 is obtained by the above method, and as shown in fig. 4, the equivalent power source is obtained by calculationEquivalent impedance
And step 3: the method comprises the following steps of carrying out simplified equivalent processing on a branch m in a distribution network containing DGs, calculating equivalent impedance and voltage difference of two nodes, and obtaining an equivalent model of the branch m of the distribution network containing DGs at the two nodes, wherein the specific method comprises the following steps:
for a DG-containing power distribution network connected to a power generation and transmission system through a step-down transformer, the injection currents of photovoltaic and wind power are set to beWill contain DG distribution network branch m is simplified into voltage difference between two nodes in two-node systemComprises the following steps:
wherein,is the equivalent impedance of the transformer;in order to be able to pass the current through the transformer,is the line impedance of j sub-branches in m branches of a DG-containing power distribution network, NmThe number of the sub-branches in the m-branch, nm,jPVThe method comprises the following steps that the number of all photovoltaic power stations on the tail node of a j sub-branch of an m branch of a DG-containing power distribution network is counted; n ism,jWTThe method comprises the steps that the number of all wind power plants on the tail node of a j branch of an m branch of a DG-containing power distribution network is counted;
equivalent impedance of branch m of distribution network containing DGComprises the following steps:
wherein N istotalThe total distributed power supply number in the power distribution network containing the DGs.
In this embodiment, three large branches of the distribution network including DG are used as evaluation objects, as shown in fig. 2, and are respectively branch one including sub-branches numbered 1, 4, and 6, branch two including sub-branches numbered 2, 5, and 7, and branch three including sub-branches numbered 3, 8, and 9The three major branches of (1) are described in the following embodiments. The injection currents of the photovoltaic power station and the wind power plant are allEquivalent impedance of step-down transformerThe number of all distributed power supplies in a power distribution network containing DGs is NtotalCalculating two-node simplified system voltage differences of the branch 1, the branch 2 and the branch 3 to be 5 respectivelyAndcorresponding branch equivalent impedances are respectivelyAndthe obtained two-node equivalent circuit of the branch of the distribution network containing the DG is shown in figure 5.
And 4, step 4: integrating the equivalent model of the two-node power generation and transmission system and the equivalent model of the two-node branch m of the distribution network containing the DGs, calculating equivalent parameters, namely equivalent impedance, equivalent load node voltage and equivalent load power, and obtaining a model for evaluating and researching the stability of the branch of the distribution network containing the DGs, wherein the specific method for calculating the equivalent parameters comprises the following steps:
calculating equivalent impedance
Calculating equivalent load node voltage
Calculating equivalenceLoad power
Wherein,the total load power of a branch m of the distribution network containing the DGs is obtained;for the total injected photovoltaic power comprising the branches m of the DG distribution network,and (4) injecting power into the total wind power of the branch m of the power distribution network containing the DG.
In this embodiment, the total load power of three large branches of the distribution network including the DG is respectively Andphotovoltaic and wind power total injection power of corresponding branch Andall 9.5+ i0.45MVA. Calculating the equivalent impedances of the two-node equivalent integration model asAndcorresponding equivalent load node voltages are respectivelyAndcorresponding equivalent load powerAndthe model for evaluating and researching the branch stability of the power distribution network containing DGs is shown in figure 6.
And 5: calculating the voltage collapse coefficient VDC of branch m in the DG-containing power distribution network according to the equivalent parametersi,m＝Vn,m 2-Vp,m 2Load overload coefficientAnd overall stability factor EDCi,m：
EDCi,m＝VDCi,m+LDCi,m＝Vn,m 2-2Zi,mSi,m
Wherein,Vd-,m 2＝Vsi 2-2Zi,mSef(i,m)；Sef(i,m)＝Si,m(1+cosβi,m)；βi,m＝φi,m-θi,m，φi,mis composed ofAngle of power factor of thetai,mIs an equivalent impedanceThe impedance angle of (c).
In the embodiment, the voltage collapse coefficients of 3 branches of a power distribution network containing DGs are respectively calculated to be VDC3,1＝0.1444、VDC3,21.5868 and VDC3,31.8550, LDC3,1＝0.6069、LDC3,20.2970 and LDC3,30.1520, overall stability factor EDC3,1＝0.7513、EDC3,21.8838 and EDC3,3＝2.0070。
Step 6: sequentially calculating comprehensive stability coefficient EDC of all branches in DG-containing power distribution networki,mThe comprehensive stability coefficient value of the DG-containing power distribution network is the minimum value min { EDC) of the comprehensive stability coefficient of each branchi,mAnd the branch with the minimum comprehensive stability coefficient value in the branches of the DG-containing power distribution network is the weakest branch in the DG-containing power distribution network.
In the present embodiment, the integrated stability factor value min { EDC of the DG-containing power distribution networki,m}＝EDC3,10.7513, the first large branch in a DG-containing distribution network is the weakest branch, i.e., branch 1, 4, 6.
Claims (6)
1. The comprehensive stability evaluation method of the branch of the DG-containing power distribution network based on the equivalent node method is characterized by comprising the following steps of:
step 1: performing combined integrated load flow calculation on the power generation and transmission system and the power distribution network containing the DGs to obtain the voltage load flow information of the root nodes of the power distribution network containing the DGsThe power generation and transmission system comprises N nodes, wherein the nodes 1-M are generator nodes, the nodes M + 1-N are load nodes, andthe root node is a connection node i containing a DG power distribution network and the power generation and transmission system, wherein i is M +1, M +2, … and N;
step 2: two-node simplified equivalent processing is carried out on the power generation and transmission system, and equivalent power supply voltage is calculatedAnd equivalent impedanceObtaining an equivalent model of a two-node power generation and transmission system on the i node;
and step 3: two-node simplified equivalent processing is carried out on branch m in the distribution network containing DG, and equivalent impedance is calculatedAnd equivalent voltage difference between two nodesObtaining an equivalent model of two nodes containing DG power distribution network branches m;
and 4, step 4: integrating the equivalent model of the two-node power generation and transmission system and the equivalent model of the two-node branch m of the distribution network containing the DG, calculating the integrated equivalent parameters to obtain a branch stability evaluation research model of the distribution network containing the DG, wherein the equivalent parameters comprise equivalent impedanceEquivalent load node voltageAnd equivalent load power
And 5: calculating a voltage collapse coefficient, a load overload coefficient and a comprehensive stability coefficient of a branch m in the DG-containing power distribution network according to the equivalent parameters;
step 6: and calculating the comprehensive stability coefficients of all the branches in the power distribution network containing the DGs in sequence, wherein the comprehensive stability coefficient value of the power distribution network is the minimum value of the comprehensive stability coefficients of all the branches, and the branch with the minimum comprehensive stability coefficient value in the branches of the power distribution network containing the DGs is the weakest branch in the power distribution network containing the DGs.
2. The DG-containing power distribution network branch comprehensive stability evaluation method based on the equivalent node method as claimed in claim 1, wherein the step 1 comprises:
step 1-1: setting a voltage initial value and a convergence standard of a root node of a DG-containing power distribution network;
step 1-2: carrying out load flow calculation of a forward-backward substitution method of the DG-containing power distribution network, and solving an iterative intermediate variable;
step 1-3: according to the iteration intermediate variable, carrying out Newton-Raphson method load flow calculation on the power transmission and transmission system, and solving the voltage value of a root node of the power distribution network containing DG;
step 1-4: calculating the voltage difference of the root node before and after two adjacent iterations, and finishing the power transmission and distribution combined integrated power flow calculation to obtain the power flow information of the root node voltage of the power distribution network containing DG if the voltage difference meets the convergence standardIf the voltage difference does not meet the convergence criterion, step 1-2 is performed.
3. The DG-containing power distribution network branch comprehensive stability evaluation method based on the equivalent node method as claimed in claim 1, wherein the method for establishing the equivalent model of the two-node power generation and transmission system on the i node in the step 2 comprises the following steps:
the following three variables are defined:
the simplified equivalent model of the two-node power generation and transmission system on the i node is as follows:
wherein G ═ {1, …, M }, L ═ M +1, …, N },equivalent impedance of thevenin, namely equivalent impedance of a two-node model of the power generation and transmission system;is an equivalent load;is the transfer impedance between the i node and the j node;is an equivalent current of the electric current,is the injected current on the j node,is the voltage of the j-node,the value of which is the load power on node j.
4. The DG-containing power distribution network branch comprehensive stability evaluation method based on the equivalent node method as claimed in claim 1, wherein the power distribution network branch simplification equivalent method in the step 3 is as follows:
for a DG-containing power distribution network connected to a power generation and transmission system through a step-down transformer, the injection currents of photovoltaic and wind power are set to beThen the branch m of the distribution network containing DG is simplified into the voltage difference between two nodes in the two-node systemComprises the following steps:
wherein,is the equivalent impedance of the transformer;is the current flowing through the transformer;is the line impedance of j sub-branches in m branches of a DG-containing power distribution network, NmThe number of the sub-branches in the m-branch, nm,jPVThe method comprises the following steps that the number of all photovoltaic power stations on the tail node of a j sub-branch of an m branch of a DG-containing power distribution network is counted; n ism,jWTThe method comprises the steps that the number of all wind power plants on the tail node of a j branch of an m branch of a DG-containing power distribution network is counted;
the branch m of the distribution network containing DG is simplified into equivalent impedance in a two-node systemComprises the following steps:
wherein N istotalThe total distributed power supply number in the power distribution network containing the DGs.
5. The DG-containing power distribution network branch comprehensive stability evaluation method based on the equivalent node method as claimed in claim 1, wherein in the step 4, equivalent parameters, namely equivalent impedanceEquivalent load node voltageAnd equivalent load powerThe specific calculation method comprises the following steps:
equivalent impedance
Equivalent load node voltage
Equivalent load power
Wherein,the total load power of a branch m of the distribution network containing the DGs is obtained;for the total injected photovoltaic power comprising the branches m of the DG distribution network,and (4) injecting power into the total wind power of the branch m of the power distribution network containing the DG.
6. The comprehensive stability assessment method for branch circuits of distribution networks containing DGs based on the equivalent node method of claim 1, wherein the voltage collapse coefficient VDC of the branch circuits of the distribution networks containing DGs in the step 5i,mLDC (load overload coefficient)i,mAnd overall stability factor EDCi,mThe calculation method comprises the following steps:
voltage collapse coefficient VDC of branch m of distribution network containing DGi,m＝Vn,m 2-Vp,m 2Coefficient of overload
Comprehensive stability coefficient EDC of branch mi,mComprises the following steps:
EDCi,m＝VDCi,m+LDCi,m＝Vn,m 2-2Zi,mSi,m
wherein,Vd-,m 2＝Vsi 2-2Zi,mSef(i,m)；Sef(i,m)＝Si,m(1+cosβi,m)；βi,m＝φi,m-θi,m，φi,mis composed ofAngle of power factor of thetai,mIs an equivalent impedanceThe impedance angle of (c).
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| CN107508323A (en) * | 2017-09-25 | 2017-12-22 | 国网浙江省电力公司经济技术研究院 | A kind of low-voltage platform area distributed photovoltaic access capability appraisal procedure and assessment system |
| CN107968398A (en) * | 2017-11-30 | 2018-04-27 | 国网江西省电力有限公司电力科学研究院 | A kind of node merger simplifies modeling method |
| CN110954775A (en) * | 2019-12-31 | 2020-04-03 | 中国华能集团清洁能源技术研究院有限公司 | Generator, power transmission line stability degree measuring method and power grid control system |
| CN111799781A (en) * | 2020-06-29 | 2020-10-20 | 中国兵器科学研究院 | Method and device for analyzing and processing power system |
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| WO2015150577A1 (en) * | 2014-04-04 | 2015-10-08 | Danmarks Tekniske Universitet | Thévenin equivalent based static contingency assessment |
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| CN101976836A (en) * | 2010-09-30 | 2011-02-16 | 河海大学 | Method for statically analyzing voltage stabilization of VSC-HVDC (Voltage-Sourced Converter-High Voltage Director Current) containing AC and DC system |
| WO2015150577A1 (en) * | 2014-04-04 | 2015-10-08 | Danmarks Tekniske Universitet | Thévenin equivalent based static contingency assessment |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN107508323A (en) * | 2017-09-25 | 2017-12-22 | 国网浙江省电力公司经济技术研究院 | A kind of low-voltage platform area distributed photovoltaic access capability appraisal procedure and assessment system |
| CN107968398A (en) * | 2017-11-30 | 2018-04-27 | 国网江西省电力有限公司电力科学研究院 | A kind of node merger simplifies modeling method |
| CN107968398B (en) * | 2017-11-30 | 2020-09-11 | 国网江西省电力有限公司电力科学研究院 | Node merging simplified modeling method |
| CN110954775A (en) * | 2019-12-31 | 2020-04-03 | 中国华能集团清洁能源技术研究院有限公司 | Generator, power transmission line stability degree measuring method and power grid control system |
| CN111799781A (en) * | 2020-06-29 | 2020-10-20 | 中国兵器科学研究院 | Method and device for analyzing and processing power system |
| CN111799781B (en) * | 2020-06-29 | 2021-06-11 | 中国兵器科学研究院 | Method and device for analyzing and processing power system |
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