CN116260129A - Method and system for evaluating influence of distributed photovoltaic access on power grid - Google Patents
Method and system for evaluating influence of distributed photovoltaic access on power grid Download PDFInfo
- Publication number
- CN116260129A CN116260129A CN202211546539.8A CN202211546539A CN116260129A CN 116260129 A CN116260129 A CN 116260129A CN 202211546539 A CN202211546539 A CN 202211546539A CN 116260129 A CN116260129 A CN 116260129A
- Authority
- CN
- China
- Prior art keywords
- node
- distributed photovoltaic
- access
- power
- distribution network
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 36
- 238000009826 distribution Methods 0.000 claims abstract description 149
- 238000004088 simulation Methods 0.000 claims abstract description 13
- 238000004364 calculation method Methods 0.000 claims description 11
- 238000003860 storage Methods 0.000 claims description 9
- 238000011156 evaluation Methods 0.000 claims description 6
- 230000008569 process Effects 0.000 claims description 6
- 230000008859 change Effects 0.000 description 8
- 238000010586 diagram Methods 0.000 description 8
- 238000004590 computer program Methods 0.000 description 7
- 230000000694 effects Effects 0.000 description 7
- 238000004458 analytical method Methods 0.000 description 6
- 230000006870 function Effects 0.000 description 4
- 238000012545 processing Methods 0.000 description 4
- 238000010248 power generation Methods 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000035699 permeability Effects 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- NAWXUBYGYWOOIX-SFHVURJKSA-N (2s)-2-[[4-[2-(2,4-diaminoquinazolin-6-yl)ethyl]benzoyl]amino]-4-methylidenepentanedioic acid Chemical compound C1=CC2=NC(N)=NC(N)=C2C=C1CCC1=CC=C(C(=O)N[C@@H](CC(=C)C(O)=O)C(O)=O)C=C1 NAWXUBYGYWOOIX-SFHVURJKSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 230000036039 immunity Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 238000004445 quantitative analysis Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
- G06Q50/00—Information and communication technology [ICT] specially adapted for implementation of business processes of specific business sectors, e.g. utilities or tourism
- G06Q50/06—Energy or water supply
-
- 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
-
- 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
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2113/00—Details relating to the application field
- G06F2113/04—Power grid distribution networks
-
- 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]
-
- 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
- H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
- H02J2300/20—The dispersed energy generation being of renewable origin
- H02J2300/22—The renewable source being solar energy
- H02J2300/24—The renewable source being solar energy of photovoltaic origin
-
- 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
- Y02E10/50—Photovoltaic [PV] energy
- Y02E10/56—Power conversion systems, e.g. maximum power point trackers
Landscapes
- Engineering & Computer Science (AREA)
- Business, Economics & Management (AREA)
- Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Power Engineering (AREA)
- Economics (AREA)
- Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- General Engineering & Computer Science (AREA)
- Marketing (AREA)
- Evolutionary Computation (AREA)
- Public Health (AREA)
- Water Supply & Treatment (AREA)
- General Health & Medical Sciences (AREA)
- Human Resources & Organizations (AREA)
- Geometry (AREA)
- Primary Health Care (AREA)
- Strategic Management (AREA)
- Tourism & Hospitality (AREA)
- General Business, Economics & Management (AREA)
- Computer Hardware Design (AREA)
- Supply And Distribution Of Alternating Current (AREA)
Abstract
The invention discloses a method and a system for evaluating the influence of distributed photovoltaic access on a power grid, wherein the method comprises the steps of obtaining a voltage influence model and a network loss influence model, wherein the voltage influence model and the network loss influence model are related to a distributed photovoltaic access scene; aiming at simulation models of the power distribution network under different distributed photovoltaic access scenes, and the voltage influence model and the network loss influence model, respectively calculating the voltage value of each node in the power distribution network under different distributed photovoltaic access scenes and the total line power loss of the power distribution network; and evaluating the influence of the distributed photovoltaic access on the power distribution network based on the voltage value of each node and the total line power loss of the power distribution network in different distributed photovoltaic access scenes. According to the method, the influence of the distributed photovoltaic access on the voltage of the power grid node and the influence of the total power loss of the line of the power distribution network are comprehensively considered, and the influence conclusion of different distributed photovoltaic access scenes on the power distribution network is obtained.
Description
Technical Field
The invention belongs to the technical field of distributed power grid connection, and particularly relates to a method and a system for evaluating influence of distributed photovoltaic access on a power grid.
Background
With the increasing living standard of people, the power consumption load changes sharply, the safety and supply pressure of the power grid increases gradually, the power distribution system meets serious challenges, such as high power consumption cost of users, easiness in large-area power failure, and the like, and the gradual exhaustion of primary energy sources and the increasing of environmental pollution, and distributed photovoltaic power generation (Distributed Photovoltaic Generation, distributed photovoltaic) is attracting wide attention. The distributed photovoltaic has the advantages of being nearby connected with load users, avoiding long-distance transmission of electric energy and effectively promoting the absorption, and can transfer a certain amount of load during peak load so as to achieve the effect of peak shifting. Therefore, the distributed photovoltaic can relieve the pressure of partial feeder line power transmission capacity, and has good influence on the operation of a power grid. Meanwhile, due to the characteristics of fluctuation, intermittence, randomness and the like of the photovoltaic output, and the weak immunity and the weak support of the distributed photovoltaic power generation system, when a high-proportion distributed photovoltaic is connected into a power grid, the power grid is subjected to a plurality of technical problems caused by improper distribution, such as active power balance, voltage rise, countercurrent, system loss increase and the like. Therefore, the research on the influence of the high-proportion distributed photovoltaic access on the power grid has very important practical significance.
Disclosure of Invention
Aiming at the problems, the invention provides a method and a system for evaluating the influence of distributed photovoltaic access on a power grid, which comprehensively consider the influence of the distributed photovoltaic access on the voltage of a power grid node and the influence of the total power loss of a line of a power distribution network, and obtain the influence conclusion of different distributed photovoltaic access scenes on the power distribution network.
In order to achieve the technical purpose and achieve the technical effect, the invention is realized by the following technical scheme:
in a first aspect, the present invention provides a method for evaluating the influence of a distributed photovoltaic access on a power distribution network, including:
acquiring a voltage influence model and a network loss influence model, wherein the voltage influence model and the network loss influence model are related to an access scene of the distributed photovoltaic;
aiming at simulation models of the power distribution network under different distributed photovoltaic access scenes, and the voltage influence model and the network loss influence model, respectively calculating the voltage value of each node in the power distribution network under different distributed photovoltaic access scenes and the total line power loss of the power distribution network;
and evaluating the influence of the distributed photovoltaic access on the power distribution network based on the voltage value of each node and the total line power loss of the power distribution network in different distributed photovoltaic access scenes.
Optionally, the access scene includes an access number of the distributed photovoltaic, an access location of the distributed photovoltaic, and an access capacity of the distributed photovoltaic.
Optionally, when the access position of the distributed photovoltaic is node p, the access number is 1, and p > m, the expression of the voltage influence model is:
in U's' m U is the voltage value of a node m on a feeder line of a power distribution network 0 For the initial voltage of the feeder line of the power distribution network, R k Representing the equivalent resistance of the k line between node k and node k-1, X k Represents the equivalent reactance of k line between node k and node k-1, n is the total number of nodes, P Li Active power, Q, of load carried by node i Li For the reactive power of the load carried by node i,
active power of distributed photovoltaic for access node p, U k Is the voltage at node k.
Optionally, when the access position of the distributed photovoltaic is node p, the access number is 1, and p < m, the expression of the voltage influence model is:
in U' m U is the voltage value of a node m on a feeder line of a power distribution network 0 For the initial voltage of the feeder line of the power distribution network, R k Representing the equivalent resistance of the k line between node k and node k-1, X k Represents the equivalent reactance of k line between node k and node k-1, n is the total number of nodes, P Li Active power, Q, of load carried by node i Li For the reactive power of the load carried by node i,
for distribution of access nodes pActive power of photovoltaic, U k Is the voltage at node k.
Optionally, when the number of accesses of the distributed photovoltaic is greater than 1, the expression of the voltage influence model is:
in U' m U is the voltage value of a node m on a feeder line of a power distribution network 0 For the initial voltage of the feeder line of the power distribution network, R k Representing the equivalent resistance of the k line between node k and node k-1, X k Represents the equivalent reactance of k line between node k and node k-1, n is the total number of nodes, P Li Active power, Q, of load carried by node i Li For the reactive power of the load carried by node i,
active power of distributed photovoltaic for access node i, U k Is the voltage at node k.
Optionally, when the access position of the distributed photovoltaic is node p and the access number is 1, the expression of the network loss influence model is:
in the Loss sum,p For accessing a single distributed photovoltaic back distribution network total power loss value, R i Equivalent resistance representing equivalent reactance of I line between node I and node I-1, I i An equivalent current representing the equivalent reactance of the i-line between node i and node i-1, R k An equivalent resistance, R, representing the equivalent reactance of the k line between node k and node k-1 i Equivalent resistance representing equivalent reactance of i line between node i and node i-1, n being total number of nodes, P Lj Active power, Q, of load carried by node j Lj Reactive power for the load carried by node j,
active power, Q, of distributed photovoltaic for access node p PVp Reactive power of distributed photovoltaic for access node p, U k For the voltage of node k, U i Is the voltage at node i.
Optionally, when the access positions of the distributed photovoltaics are nodes p1, p2 … pm, pm < n, and the number of accesses is greater than 1, the expression of the network loss influence model is:
in the method, in the process of the invention,
for the total power loss value of the distribution network after being connected with a plurality of distributed photovoltaics, R i 、R k 、R f Representing equivalent resistances between i line between node i and node i-1, k line between node k and node k-1, and f line between node f and node f-1, n being the total number of nodes, P Lj 、P Li Active power, Q, of load carried by nodes j, i Lj 、Q Li Reactive power of the load carried for nodes j, i, < >>
Active power of distributed photovoltaic for access node pm, U k For the voltage of node k, U i For the voltage at node i,
reactive power of the distributed photovoltaic for the access node pm.
Optionally, the evaluation method further comprises:
aiming at a simulation model of the distribution network which is not connected with the distributed photovoltaic, calculating the voltage value of each node in the distribution network and the total line power loss of the distribution network;
and evaluating the influence of the distributed photovoltaic access on the power distribution network based on the voltage value of each node in the power distribution network and the total line power loss of the power distribution network when the distributed photovoltaic is not accessed, and the voltage value of each node and the total line power loss of the power distribution network in different distributed photovoltaic access scenes.
Optionally, when the distributed photovoltaic is not connected, the calculation formula of the voltage value of each node in the power distribution network is as follows:
U m ＝U 0 -ΔU m
in U m U is the voltage value of a node m on a feeder line of a power distribution network 0 For initial voltage of distribution network feeder, deltaU m The voltage difference between the node m and the node m-1 on the power distribution network feed line is set;
the calculation formula of the total power loss of the line of the power distribution network is as follows:
in the Loss sum For the total power loss of the distribution network when the distributed photovoltaic is not connected, R i Representing the equivalent resistance of the I-line between node I and node I-1, I i Representing the equivalent current of i line between node i and node i-1, n is the total number of nodes, P Lj Active power, Q, of load carried by node j Lj Reactive power for load carried by node j, U i Is the voltage at node i.
In a second aspect, the invention provides a system for evaluating the influence of distributed photovoltaic access on a power grid, which comprises a storage medium and a processor;
the storage medium is used for storing instructions;
the processor is configured to operate in accordance with the instructions to perform the method according to any one of the first aspects.
Compared with the prior art, the invention has the beneficial effects that:
the invention provides a voltage influence model and a network loss influence model related to a distributed photovoltaic access scene, and aims at a simulation model of a power distribution network under different distributed photovoltaic access scenes, the voltage influence model and the network loss influence model are used for simulating and analyzing the voltage value of each node of the distributed photovoltaic access power distribution network under different scenes and the total line power loss of the power distribution network, so that the influence conclusion of high-proportion distributed photovoltaic access on the power distribution network is obtained, the large-scale development of the distributed photovoltaic can be adapted, a reference basis is provided for the power grid adaptability and related grid-connected technology improvement of high-proportion distributed photovoltaic power generation, the problem of the planning scheme of the distributed photovoltaic access power distribution network can be effectively solved, and the efficient consumption and the utilization of the distributed photovoltaic can be promoted.
Drawings
In order that the invention may be more readily understood, a more particular description of the invention will be rendered by reference to specific embodiments that are illustrated in the appended drawings, in which:
fig. 1 is a flow chart of a method for evaluating an influence of a distributed photovoltaic access on a power grid according to an embodiment of the present invention;
FIG. 2 is a diagram of a radial distribution network model with single feeder lines of distributed photovoltaic;
FIG. 3 is a diagram of a simulation model of an IEEE33 distribution network;
FIG. 4 is a graph showing the effect of photovoltaic access to different nodes on voltage distribution;
FIG. 5 is a graph showing the effect of photovoltaic single point access and decentralized access on voltage distribution;
the effect of the different capacities of photovoltaic access nodes 6 on the voltage distribution of fig. 6;
fig. 7 effect of different capacity photovoltaic access nodes 12 on voltage distribution
The effect of different capacity photovoltaic access nodes 18 on voltage distribution of fig. 8.
Detailed Description
The present invention will be described in further detail with reference to the following examples in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the invention.
The principle of application of the invention is described in detail below with reference to the accompanying drawings.
Example 1
The embodiment of the invention provides a method for evaluating the influence of distributed photovoltaic access on a power distribution network, as shown in fig. 1, comprising the following steps:
(1) Acquiring a voltage influence model and a network loss influence model, wherein the voltage influence model and the network loss influence model are related to an access scene of the distributed photovoltaic; in a specific implementation process, the access scene comprises the access quantity of the distributed photovoltaic, the access position of the distributed photovoltaic and the access capacity of the distributed photovoltaic;
(2) Aiming at simulation models of the power distribution network under different distributed photovoltaic access scenes, and the voltage influence model and the network loss influence model, respectively calculating the voltage value of each node in the power distribution network under different distributed photovoltaic access scenes and the total line power loss of the power distribution network;
(3) And evaluating the influence of the distributed photovoltaic access on the power distribution network based on the voltage value of each node and the total line power loss of the power distribution network in different distributed photovoltaic access scenes.
In a specific implementation manner of the embodiment of the present invention, when the access position of the distributed photovoltaic is node p, the number of accesses is 1, and p > m, the expression of the voltage influence model is:
in U's' m U is the voltage value of a node m on a feeder line of a power distribution network 0 For the initial voltage of the feeder line of the power distribution network, R k Representing the equivalent resistance of the k line between node k and node k-1, X k Represents the equivalent reactance of k line between node k and node k-1, n is the total number of nodes, P Li Active power, Q, of load carried by node i Li For the reactive power of the load carried by node i,
active power of distributed photovoltaic for access node p, U k Is the voltage at node k.
In a specific implementation manner of the embodiment of the present invention, when the access position of the distributed photovoltaic is node p, the number of accesses is 1, and p < m, the expression of the voltage influence model is:
in U' m U is the voltage value of a node m on a feeder line of a power distribution network 0 For the initial voltage of the feeder line of the power distribution network, R k Representing the equivalent resistance of the k line between node k and node k-1, X k Represents the equivalent reactance of k line between node k and node k-1, n is the total number of nodes, P Li Active power, Q, of load carried by node i Li For the reactive power of the load carried by node i,
active power of distributed photovoltaic for access node p, U k Is the voltage at node k.
In a specific implementation manner of the embodiment of the present invention, when the number of accesses of the distributed photovoltaic is greater than 1, the expression of the voltage influence model is:
in U' m U is the voltage value of a node m on a feeder line of a power distribution network 0 For the initial voltage of the feeder line of the power distribution network, R k Representing the equivalent resistance of the k line between node k and node k-1, X k Represents the equivalent reactance of k line between node k and node k-1, n is the total number of nodes, P Li Active power, Q, of load carried by node i Li For the reactive power of the load carried by node i,
active power of distributed photovoltaic for access node i, U k Is the voltage at node k.
In a specific implementation manner of the embodiment of the present invention, when the access position of the distributed photovoltaic is node p and the number of accesses is 1, the expression of the network loss influence model is:
in the Loss sum,p For accessing a single distributed photovoltaic back distribution network total power loss value, R i Equivalent resistance representing equivalent reactance of I line between node I and node I-1, I i An equivalent current representing the equivalent reactance of the i-line between node i and node i-1, R k An equivalent resistance, R, representing the equivalent reactance of the k line between node k and node k-1 i Equivalent resistance representing equivalent reactance of i line between node i and node i-1, n being total number of nodes, P Lj Active power, Q, of load carried by node j Lj Reactive power for the load carried by node j,
active power, Q, of distributed photovoltaic for access node p PVp Reactive power of distributed photovoltaic for access node p, U k For the voltage of node k, U i Is the voltage at node i.
In a specific implementation manner of the embodiment of the present invention, when the access positions of the distributed photovoltaic are nodes p1, p2 … pm, pm < n, and the number of accesses is greater than 1, the expression of the network loss influence model is:
in the method, in the process of the invention,
for the total power loss value of the distribution network after being connected with a plurality of distributed photovoltaics, R i 、R k 、R f Represents the equivalent resistance between i line between node i and node i-1, k line between node k and node k-1, and f line between node f and node f-1, n is the total number of nodes,P Lj 、P Li active power, Q, of load carried by nodes j, i Lj 、Q Li Reactive power of the load carried for nodes j, i, < >>
Active power of distributed photovoltaic for access node pm, U k For the voltage of node k, U i For the voltage at node i,
reactive power of the distributed photovoltaic for the access node pm.
In a specific implementation manner of the embodiment of the present invention, based on the voltage value of each node and the total line power loss of the power distribution network in different distributed photovoltaic access scenarios, the influence of the distributed photovoltaic access on the power distribution network is evaluated, and specifically includes the following steps:
subtracting the calculated voltage values of the node m on the power distribution network feeder under different distributed photovoltaic access scenes to obtain voltage deviation;
and subtracting the calculated total power loss values of the distribution network under different distributed photovoltaic access scenes to obtain the variation value of the total power loss values of the distribution network.
In a specific implementation of the embodiment of the present invention, the evaluation method further includes:
aiming at a simulation model of the distribution network which is not connected with the distributed photovoltaic, calculating the voltage value of each node in the distribution network and the total line power loss of the distribution network;
and evaluating the influence of the distributed photovoltaic access on the power distribution network based on the voltage value of each node in the power distribution network and the total line power loss of the power distribution network when the distributed photovoltaic is not accessed, and the voltage value of each node and the total line power loss of the power distribution network in different distributed photovoltaic access scenes.
The calculation formula of the voltage value of each node in the power distribution network when the distributed photovoltaic is not connected is as follows:
U m ＝U 0 -ΔU m
in U m U is the voltage value of a node m on a feeder line of a power distribution network 0 For initial voltage of distribution network feeder, deltaU m The voltage difference between the node m and the node m-1 on the power distribution network feed line is set;
the calculation formula of the total power loss of the line of the power distribution network is as follows:
Loss sum for the total power loss of the distribution network when the distributed photovoltaic is not connected, R i Representing an i-line between node i and node i-1
In the formula, equivalent resistance I i Representing the equivalent current of i line between node i and node i-1, n is the total number of nodes, P Lj Active power, Q, of load carried by node j Lj Reactive power for load carried by node j, U i Is the voltage at node i.
In a specific implementation manner of the embodiment of the present invention, based on a voltage value of each node in the power distribution network and a total line power loss of the power distribution network when the distributed photovoltaic is not connected, and a voltage value of each node and a total line power loss of the power distribution network in different distributed photovoltaic connection scenarios, the method performs an evaluation of an influence of the distributed photovoltaic connection on the power distribution network, and specifically includes the following steps:
subtracting the voltage values of the node m on the power distribution network feeder calculated under the conditions of not accessing the distributed photovoltaic and different distributed photovoltaic access to obtain voltage deviation;
and subtracting the calculated total power loss values of the distribution network under the access scenes of the non-accessed distributed photovoltaic and the different distributed photovoltaic to obtain the variation value of the total power loss value of the distribution network.
When analyzing the total power loss value of the distribution network calculated under different distributed photovoltaic access scenes and the total power loss value of the distribution network calculated under the condition of not accessing the distributed light, the following formula can be adopted:
when the access position of the distributed photovoltaic is node p and the access quantity is 1, the total power loss of the distribution networkThe calculation formula of the consumption change value is as follows: Δloss=loss sum,p -Loss sum
When the access positions of the distributed photovoltaic are node m and node p, and the access quantity is more than 1, the calculation formula of the total power loss change value of the distribution network is as follows: Δloss' =loss sum,m,p -Loss sum 。
The evaluation method in the embodiment of the present invention is described in detail below with reference to a specific embodiment.
After the distributed photovoltaic single-point or multi-point random access power distribution network, each feeder does not need to be analyzed. In fact, when grid dispatching is performed, different loads are reasonably evenly distributed to each feeder line in the power distribution network, and each feeder line has similar characteristics as a whole. Therefore, only the feeder line directly connected with the distributed photovoltaic can be selected for analysis.
Because of the focus of power supply quality and power supply economy, voltage deviation (i.e. difference between voltage values of different scenes of the same node, for example, difference between voltage values when photovoltaic voltage is not connected with the photovoltaic access node 6) and total line power loss of the power distribution network are adopted as directions for influencing quantitative analysis;
establishing a voltage influence model; in trend analysis, the network structure of the distribution network can be equivalently understood as a single-power radial network, so that the distributed Photovoltaic (PV) can be obtained i I=1, 2, … n), see in particular fig. 2. N nodes (n is more than or equal to 0); u (U) i Representing the voltage at node i, U 0 Representing an initial voltage of a feeder line of the power distribution network; r is R i +jX i Representing the equivalent impedance of the i-line (i.e., the line between node i and node i-1); s is S Li ＝P Li +jQ Li Representing the total power of the load carried by node i, assuming that all nodes have load access, if there is no load access, S Li ＝0。PV i Representing a distributed photovoltaic connected to a node i, the capacity of which is represented by S PVi ＝P PVi +jQ PVi Indicating that if node i has no distributed photovoltaic access, S PVi =0. The direction of the bus pointing to the circuit is positive, the load direction is positive, and the distribution is realizedThe direction of the formula photovoltaic is the opposite direction.
If the distributed photovoltaic is not connected into the power distribution network, the voltage expression of the node m is as follows:
U m ＝U 0 -ΔU m (1)
in U m U is the voltage value of a node m on a feeder line of a power distribution network 0 For initial voltage of distribution network feeder, deltaU m The voltage difference between the node m and the node m-1 on the power distribution network feed line is set;
assuming that the access node of the distributed photovoltaic is p, when p > m, the single distributed photovoltaic is accessed after the node m, and the voltage expression of the node m is:
assuming that the access node of the distributed photovoltaic is p, when p < m, the single distributed photovoltaic is accessed before the node m, and the voltage expression of the node m is:
consider the case where multiple distributed photovoltaics are connected to feeders in a distribution network. The voltage expression of node m is:
in U's' m "is the voltage value of node m on distribution feeder, U 0 For the initial voltage of the feeder line of the power distribution network, R k Representing the equivalent resistance of the k line between node k and node k-1, X k Represents the equivalent reactance of k line between node k and node k-1, n is the total number of nodes, P Li Active power, Q, of load carried by node i Li For the reactive power of the load carried by node i,
active power of distributed photovoltaic for access node i, U k Is the voltage of node k;
establishing a network loss influence model, specifically:
for the feeder line of the distribution network, when no distributed photovoltaic access exists, the line power loss between the node m and the node m-1 is as follows:
the total loss of the circuit is as follows:
a single distributed photovoltaic connection to node P, power P PVm +jQ PVm .. For the feeder line between the node m and the node m-1, since the power on the line is changed, the line power loss between the node m and the node m-1 is:
the loss of the distribution network is as follows:
after a single distributed photovoltaic access, the change in total power loss of the line can be expressed as:
when the access positions of the distributed photovoltaics are nodes p1 and p2 … pm, pm < n, and the access quantity is greater than 1, the expression of the network loss influence model is as follows:
in the method, in the process of the invention,
for the total power loss value of the distribution network after being connected with a plurality of distributed photovoltaics, R i 、R k 、R f Representing equivalent resistances between i line between node i and node i-1, k line between node k and node k-1, and f line between node f and node f-1, n being the total number of nodes, P Lj 、P Li Active power, Q, of load carried by nodes j, i Lj 、Q Li Reactive power of the load carried for nodes j, i, < >>
Active power of distributed photovoltaic for access node pm, U k For the voltage of node k, U i For the voltage at node i,
reactive power of distributed photovoltaic for access node pm
After multiple distributed photovoltaic accesses, the change of the total power loss of the line can be expressed as:
ΔLoss'＝Loss sum,pm -Loss sum (11)
taking an IEEE33 node as an example, constructing a simulation calculation example, carrying out simulation verification analysis, constructing an IEEE33 node power distribution network simulation model by adopting OpenDSS power distribution network simulation calculation software, constructing a typical scene of distributed photovoltaic access from an access position and an access capacity, and carrying out calculation analysis.
Analyzing the influence of different access positions on voltage deviation, setting the capacity condition of distributed Photovoltaic (PV) unchanged, changing the position of a feeder line of the distributed photovoltaic access distribution network, selecting the head part, the middle part and the tail end of the distribution network for analysis to obtain the node voltage change degree under different access positions, sequentially connecting the distributed photovoltaic to four conditions of node 3, node 6, node 12 and node 18, calculating the voltage value of each node under each condition according to formulas (2) - (3), and simultaneously comparing the results of the non-accessed distributed photovoltaic to obtain the influence of the distributed photovoltaic on the voltage deviation, wherein the figure 4 is particularly referred to.
Comparing the influence of the distributed photovoltaic single-point access and the multipoint access on the voltage deviation, and uniformly dispersing the photovoltaic with the same total capacity into the nodes at the head, the middle and the tail ends of the distributed photovoltaic dispersed access with the same total capacity into the node 3, the node 6, the node 12 and the node 18 according to the formula (4), thereby obtaining the voltage distribution situation of each node, and particularly referring to fig. 5.
And (3) analyzing the influence of different access capacities on the voltage deviation, changing the capacity of the distributed photovoltaic to simulate and analyze the influence of the distributed photovoltaic on the voltage deviation when the condition of the access position is unchanged, analyzing according to the permeability of 10%, 30% and 50%, namely, the different capacities are accessed to the head (node 6), the middle (node 12) and the tail (node 18) of the power distribution network, calculating according to formulas (2) - (4) to obtain the voltage value of each node under three capacity situations, analyzing the voltage distribution and the voltage rise of each node, and focusing on the monotonicity condition of the voltage distribution, and particularly referring to fig. 6-8. The larger the photovoltaic access capacity of the same access node is, the more obvious the voltage rise amplitude of each node of the feeder line is, and the more obvious the voltage rise amplitude of each node is after the access node is. When the access end node and the access capacity are too large, the node voltage distribution of the feeder line shows obvious monotone change.
The method comprises the steps of setting the condition of the distributed photovoltaic capacity unchanged, sequentially connecting the same capacity of the distributed photovoltaic to a head part (node 6), a middle part (node 12) and a tail end (node 18) for analysis, calculating according to a formula (8) to obtain network loss of a distribution network, comparing network loss results without distributed photovoltaic access, comparing network loss reduction conditions, and comparing network loss change conditions of feeder lines with different load sizes.
Table 1 network loss calculation results for different access locations
When the condition of the access position is unchanged, the capacity of the distributed photovoltaic is changed to simulate and analyze the influence of the distributed photovoltaic on the voltage deviation, and the influence is analyzed according to the permeability of 10%, 30% and 50%, namely, the different capacities are accessed into the head (node 6), the middle (node 12) and the tail (node 18) of the power distribution network, the network loss of the power distribution network is calculated according to the formula (8) or the formula (10), meanwhile, the network loss results of the distributed photovoltaic access-free network are compared, the network loss reduction condition is compared, and the network loss change condition of feeder lines with different load sizes is compared.
Example 3
Based on the same inventive concept as embodiment 1, an embodiment of the present invention provides a system for evaluating an influence of distributed photovoltaic access on a power grid, including a storage medium and a processor;
the storage medium is used for storing instructions;
the processor is operative according to the instructions to perform the steps of the method according to any one of embodiment 1.
It will be appreciated by those skilled in the art that embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
The foregoing is merely a preferred embodiment of the present invention, and it should be noted that it will be apparent to those skilled in the art that modifications and variations can be made without departing from the technical principles of the present invention, and these modifications and variations should also be regarded as the scope of the invention.
Claims (10)
1. A method for evaluating the impact of distributed photovoltaic access on a power distribution network, comprising:
acquiring a voltage influence model and a network loss influence model, wherein the voltage influence model and the network loss influence model are related to an access scene of the distributed photovoltaic;
aiming at simulation models of the power distribution network under different distributed photovoltaic access scenes, and the voltage influence model and the network loss influence model, respectively calculating the voltage value of each node in the power distribution network under different distributed photovoltaic access scenes and the total line power loss of the power distribution network;
and evaluating the influence of the distributed photovoltaic access on the power distribution network based on the voltage value of each node and the total line power loss of the power distribution network in different distributed photovoltaic access scenes.
2. The method for evaluating the influence of distributed photovoltaic access on a power grid according to claim 1, wherein: the access scene comprises the access quantity of the distributed photovoltaic, the access position of the distributed photovoltaic and the access capacity of the distributed photovoltaic.
3. The method for evaluating the influence of distributed photovoltaic access on a power grid according to claim 1, wherein: when the access position of the distributed photovoltaic is node p, the access quantity is 1, and p > m, the expression of the voltage influence model is as follows:
in U's' m U is the voltage value of a node m on a feeder line of a power distribution network 0 For the initial voltage of the feeder line of the power distribution network, R k Representing the equivalent resistance of the k line between node k and node k-1, X k Represents the equivalent reactance of k line between node k and node k-1, n is the total number of nodes, P Li Active power, Q, of load carried by node i Li For the reactive power of the load carried by node i,
active power of distributed photovoltaic for access node p, U k Is the voltage at node k.
4. The method for evaluating the influence of distributed photovoltaic access on a power grid according to claim 1, wherein: when the access position of the distributed photovoltaic is node p, the access quantity is 1, and p < m, the expression of the voltage influence model is as follows:
in U' m U is the voltage value of a node m on a feeder line of a power distribution network 0 For the initial voltage of the feeder line of the power distribution network, R k Representing the equivalent resistance of the k line between node k and node k-1, X k Represents the equivalent reactance of k line between node k and node k-1, n is the total number of nodes, P Li Active power, Q, of load carried by node i Li For the reactive power of the load carried by node i,
active power of distributed photovoltaic for access node p, U k Is the voltage at node k.
5. The method for evaluating the influence of distributed photovoltaic access on a power grid according to claim 1, wherein: when the number of the distributed photovoltaic accesses is larger than 1, the expression of the voltage influence model is as follows:
in U's' m "is the voltage value of node m on the feeder line of the power distribution network, U 0 For the initial voltage of the feeder line of the power distribution network, R k Representing the equivalent resistance of the k line between node k and node k-1, X k Represents the equivalent reactance of k line between node k and node k-1, n is the total number of nodes, P Li Active power, Q, of load carried by node i Li For the reactive power of the load carried by node i,
active power of distributed photovoltaic for access node i, U k Is the voltage at node k.
6. The method for evaluating the influence of distributed photovoltaic access on a power grid according to claim 1, wherein: when the access position of the distributed photovoltaic is node p and the access quantity is 1, the expression of the network loss influence model is as follows:
in the Loss sum,p For accessing a single distributed photovoltaic back distribution network total power loss value, R i Equivalent resistance representing equivalent reactance of I line between node I and node I-1, I i An equivalent current representing the equivalent reactance of the i-line between node i and node i-1, R k An equivalent resistance, R, representing the equivalent reactance of the k line between node k and node k-1 i Equivalent resistance representing equivalent reactance of i line between node i and node i-1, n being total number of nodes, P Lj Active power, Q, of load carried by node j Lj Reactive power for the load carried by node j,
active power of distributed photovoltaic for access node p, +.>
Reactive power of distributed photovoltaic for access node p, U k For the voltage of node k, U i Is the voltage at node i.
7. The method for evaluating the influence of distributed photovoltaic access on a power grid according to claim 1, wherein: when the access positions of the distributed photovoltaics are nodes p1 and p2 … pm, pm < n, and the access quantity is greater than 1, the expression of the network loss influence model is as follows:
in the method, in the process of the invention,
for the total power loss value of the distribution network after being connected with a plurality of distributed photovoltaics, R i 、R k 、R f Representing equivalent resistances between i line between node i and node i-1, k line between node k and node k-1, and f line between node f and node f-1, n being the total number of nodes, P Lj 、P Li Active power, Q, of load carried by nodes j, i Lj 、Q Li Reactive power of the load carried for nodes j, i, < >>
Active power of distributed photovoltaic for access node pm, U k For the voltage of node k, U i For the voltage at node i,
reactive power of the distributed photovoltaic for the access node pm.
8. The method for evaluating the influence of distributed photovoltaic access on a power grid according to claim 1, wherein: the evaluation method further comprises:
aiming at a simulation model of the distribution network which is not connected with the distributed photovoltaic, calculating the voltage value of each node in the distribution network and the total line power loss of the distribution network;
and evaluating the influence of the distributed photovoltaic access on the power distribution network based on the voltage value of each node in the power distribution network and the total line power loss of the power distribution network when the distributed photovoltaic is not accessed, and the voltage value of each node and the total line power loss of the power distribution network in different distributed photovoltaic access scenes.
9. The method for evaluating the influence of distributed photovoltaic access on a power grid according to claim 8, wherein: the calculation formula of the voltage value of each node in the power distribution network when the distributed photovoltaic is not connected is as follows:
U m ＝U 0 -ΔU m
in U m U is the voltage value of a node m on a feeder line of a power distribution network 0 For initial voltage of distribution network feeder, deltaU m For upper node of feeder line of distribution networkA voltage difference between m and node m-1;
the calculation formula of the total power loss of the line of the power distribution network is as follows:
in the Loss sum For the total power loss of the distribution network when the distributed photovoltaic is not connected, R i Representing the equivalent resistance of the I-line between node I and node I-1, I i Representing the equivalent current of i line between node i and node i-1, n is the total number of nodes, P Lj Active power, Q, of load carried by node j Lj Reactive power for load carried by node j, U i Is the voltage at node i.
10. An evaluation system of distributed photovoltaic access to electric wire netting influence, its characterized in that: including a storage medium and a processor;
the storage medium is used for storing instructions;
the processor is operative to perform the method according to any one of claims 1-9, in accordance with the instructions.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211546539.8A CN116260129A (en) | 2022-12-05 | 2022-12-05 | Method and system for evaluating influence of distributed photovoltaic access on power grid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211546539.8A CN116260129A (en) | 2022-12-05 | 2022-12-05 | Method and system for evaluating influence of distributed photovoltaic access on power grid |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116260129A true CN116260129A (en) | 2023-06-13 |
Family
ID=86678276
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211546539.8A Pending CN116260129A (en) | 2022-12-05 | 2022-12-05 | Method and system for evaluating influence of distributed photovoltaic access on power grid |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116260129A (en) |
-
2022
- 2022-12-05 CN CN202211546539.8A patent/CN116260129A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP7407894B1 (en) | Control method, device and electronic equipment for hybrid energy storage system | |
| CN109818369B (en) | Distributed power supply planning method considering output fuzzy randomness | |
| CN113988384A (en) | Energy storage capacity optimal configuration method for improving reliability of power distribution network | |
| CN112865089A (en) | Improved large-scale scene analysis method for active power distribution network | |
| CN116031887A (en) | Power grid simulation analysis calculation data generation method, system, equipment and medium | |
| Kumar et al. | An optimized framework of the integrated renewable energy and power quality model for the smart grid | |
| CN112564160B (en) | Wind power uncertainty-based random configuration method for energy storage system, terminal and storage medium | |
| CN114676569A (en) | Power grid simulation analysis example, and generation method, generation system, equipment and medium thereof | |
| Rezaeian‐Marjani et al. | Probabilistic assessment of D‐STATCOM operation considering correlated uncertain variables | |
| CN117293906A (en) | Distributed photovoltaic bearing capacity rapid evaluation method and system for power distribution network based on gravity center theory | |
| CN116260129A (en) | Method and system for evaluating influence of distributed photovoltaic access on power grid | |
| CN116826859A (en) | Power supply carbon-electricity collaborative planning method, device, equipment and storage medium | |
| CN115912493A (en) | Distributed power supply access method, electronic equipment, power distribution network and storage medium | |
| CN115545793A (en) | Novel power system power grid foundation model construction method, system, equipment and medium | |
| CN110707689B (en) | Stability analysis method and device suitable for full-clean energy power generation power grid | |
| CN111884254B (en) | Distributed photovoltaic absorption access method and device based on double random simulation | |
| CN108009665A (en) | A kind of optimal load flow Optimized model for considering flexible electric load | |
| CN108649596B (en) | Battery energy storage system dynamic model suitable for load modeling | |
| CN112560947A (en) | Clustering method and device based on energy supply and demand structure analysis | |
| CN116663936B (en) | Capacity expansion planning method, device, equipment and medium for electric comprehensive energy system | |
| CN115642597B (en) | Distributed photovoltaic bearing capacity calculation method and device | |
| CN117713176B (en) | Source network charge storage low-carbon operation method and device, electronic equipment and storage medium | |
| CN115423262A (en) | Carbon emission assessment method, system, equipment and medium based on graph theory traceability | |
| CN103887791B (en) | A kind of distribution interconnection switch load switching optimization method | |
| CN114676902B (en) | Optimal planning method and system for park power distribution system of high-proportion renewable energy |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |