CN113437763B - Method and system for determining limit access scale and short-circuit capacity of new energy station - Google Patents

Method and system for determining limit access scale and short-circuit capacity of new energy station Download PDF

Info

Publication number
CN113437763B
CN113437763B CN202110535001.6A CN202110535001A CN113437763B CN 113437763 B CN113437763 B CN 113437763B CN 202110535001 A CN202110535001 A CN 202110535001A CN 113437763 B CN113437763 B CN 113437763B
Authority
CN
China
Prior art keywords
new energy
station
grid
voltage
point
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.)
Active
Application number
CN202110535001.6A
Other languages
Chinese (zh)
Other versions
CN113437763A (en
Inventor
孙华东
赵兵
于琳
徐式蕴
习工伟
郑帅飞
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
China Electric Power Research Institute Co Ltd CEPRI
State Grid Jibei Electric Power Co Ltd
Original Assignee
China Electric Power Research Institute Co Ltd CEPRI
State Grid Jibei Electric Power Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by China Electric Power Research Institute Co Ltd CEPRI, State Grid Jibei Electric Power Co Ltd filed Critical China Electric Power Research Institute Co Ltd CEPRI
Priority to CN202110535001.6A priority Critical patent/CN113437763B/en
Publication of CN113437763A publication Critical patent/CN113437763A/en
Application granted granted Critical
Publication of CN113437763B publication Critical patent/CN113437763B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • 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
    • H02J3/46—Controlling of the sharing of output between the generators, converters, or transformers
    • H02J3/466—Scheduling the operation of the generators, e.g. connecting or disconnecting generators to meet a given demand
    • 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
    • H02J3/46—Controlling of the sharing of output between the generators, converters, or transformers
    • H02J3/48—Controlling the sharing of the in-phase component
    • 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
    • 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
    • H02J2300/28—The renewable source being wind energy
    • 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)
  • Power Engineering (AREA)
  • Supply And Distribution Of Alternating Current (AREA)

Abstract

The invention discloses a method and a system for determining the limit access scale of a new energy station, comprising the following steps: establishing a first low-voltage mathematical model of the new energy single-station grid-connected point when the new energy single-station grid-connected system generates low voltage; establishing a second low-voltage mathematical model of each new energy station grid-connected point when the new energy multi-station grid-connected system generates low voltage based on the first low-voltage mathematical model; and determining the limit access scale of each new energy station in the target new energy multi-station grid-connected system based on the low voltage limit according to the second low voltage mathematical model. The invention also discloses a method and a system for determining the limit short-circuit capacity of the alternating current system in the new energy multi-station grid-connected system, wherein the method comprises the following steps: establishing a first low-voltage mathematical model; establishing a second low-voltage mathematical model based on the first low-voltage mathematical model; and determining the limit short-circuit capacity required to be provided by the alternating current system in the running new energy multi-station grid-connected system according to the second low-voltage mathematical model.

Description

Method and system for determining limit access scale and short-circuit capacity of new energy station
Technical Field
The invention relates to the technical field of renewable energy grid-connected stability analysis, in particular to a method and a system for limiting access scale of a new energy station and short-circuit capacity of an alternating current system.
Background
By the year 2020, the estimated installed capacity of the renewable energy source planning for the open-home would reach 20000MW and 2030, and the estimated installed capacity of the renewable energy source planning for the open-home would reach 50000MW. The Zhang Bei flexible-straightening engineering can solve the problem that the power of a new energy installation with the power of 14000MW is sent out, and the new energy installation with the power of 6000MW is still limited in 2020. The active power flowing in the system causes low voltage problems due to the existence of system impedance. The larger the new energy access scale is, the more serious the low voltage is. It is needed to analyze the relationship between the low voltage and the access scale of the new energy grid-connected system, and realize the maximum access scale of the new energy under the premise of ensuring the safe operation of the system.
At present, the research on the access scale of the new energy source limit mainly aims at analyzing the limit of overvoltage to the access scale of the new energy source, and the attention to the problem of low voltage is in a preliminary stage.
Disclosure of Invention
In view of the above problems, according to one aspect of the present invention, there is provided a method of determining a limit access scale of a new energy station, comprising:
Establishing a first low-voltage mathematical model of the new energy single-station grid-connected point when the new energy single-station grid-connected system generates low voltage;
establishing a second low-voltage mathematical model of each new energy station grid-connected point when the new energy multi-station grid-connected system generates low voltage based on the first low-voltage mathematical model;
and determining the limit access scale of each new energy station in the target new energy multi-station grid-connected system based on the low voltage limit according to the second low voltage mathematical model.
According to another aspect of the present invention, there is provided a method of determining an ac system limit short circuit capacity in a new energy multi-station grid-connected system, the method comprising:
establishing a first low-voltage mathematical model of the new energy single-station grid-connected point when the new energy single-station grid-connected system generates low voltage;
establishing a second low-voltage mathematical model of each new energy station grid-connected point when the new energy multi-station grid-connected system generates low voltage based on the first low-voltage mathematical model;
and determining the limit short-circuit capacity required to be provided by an alternating current system in the running new energy multi-station grid-connected system according to the second low-voltage mathematical model.
Preferably, the establishing a first low-voltage mathematical model of the new energy single-station grid-connected point when the new energy single-station grid-connected system generates low voltage includes:
Determining short circuit capacity at a grid-connected point in a new energy single-station grid-connected system comprises the following steps:
wherein S is ac1 In the grid-connected system of the new energy single station, the short circuit capacity of the grid-connected point of the new energy single station, x 1 The impedance between the new energy single-station grid-connected point and the common connection point of the alternating current system is shown as x, and the equivalent impedance of the alternating current system is shown as seen from the common connection point;
when determining that the grid-connected system of the new energy single-station generates low voltage, the current flowing into the alternating current system by the new energy single-station comprises the following steps:
wherein I is 1 The method comprises the steps that output current flowing to a public connection point for a new energy single-station grid connection point is I, current flowing to an alternating current system from the public connection point is U 1 The voltage of the grid-connected point of the single station of the new energy source, P 1 When low voltage appears for the new energy single-station grid-connected system, the active power sent by the new energy single-station;
when the low voltage of the new energy single-station system occurs, the transverse component of the voltage drop between the voltage of the public connection point and the equivalent potential of the alternating current system is determined, and the method comprises the following steps:
wherein δU is 0 Is the transverse component of voltage drop between the public connection point and the equivalent power supply potential of the alternating current system, U 0 E is the equivalent power supply potential of the alternating current system;
when the low voltage of the new energy single-station grid-connected system is determined, the relation between the voltage drop transverse component of the new energy single-station grid-connected point and the voltage of the new energy injection active power, the grid-connected point and the short circuit capacity is determined, so that the first low voltage mathematical model of the new energy single-station grid-connected point is established, and the method comprises the following steps:
Wherein δU is 1 Is the transverse component of the voltage drop between the station grid-connected point and the equivalent mains potential of the ac system.
Preferably, the establishing a second low-voltage mathematical model of each new energy station grid-connected point when the new energy multi-station grid-connected system generates low voltage based on the first low-voltage mathematical model includes:
determining the relation between the injected active power and the installed capacity of the new energy multi-station grid-connected system at low voltage, wherein the method comprises the following steps:
P i ＝n i S i ，
wherein P is i Active power of the grid-connected point is injected for the new energy station i, S i For the installed capacity of the new energy station i, n i The power factor of the new energy station i;
determining short-circuit capacity at a grid-connected point of a new energy station i comprises the following steps:
wherein S is ac,i Short-circuit capacity of the grid-connected point access of the new energy station i; x is x i Equivalent impedance from the point of the new energy station i to the public connection point is obtained; x is the equivalent impedance of the alternating current system seen from the public connection point;
according to S ac，i Determining equivalent impedance x from grid-connected point to public connection point of new energy field station i i Comprising:
wherein S is ac Short circuit capacity provided for an ac system at a common connection point.
When determining that low voltage occurs in the new energy multi-station grid-connected system, and when the voltage of each grid-connected point reaches a low voltage limit value, the current sent out by the new energy station i comprises the following steps:
Wherein I is i The current is sent out for the new energy station i; p (P) i Active power of the new energy station i; u (U) i The grid-connected point voltage of the new energy station i is set;
when low voltage occurs in the new energy multi-station grid-connected system, determining the transverse component of voltage drop between the grid-connected points and the public connection points of each new energy station comprises the following steps:
I 1 ×x 1 ＝I 2 ×x 2 ＝…＝I n ×x n ，1≤i≤n；
when low voltage occurs in the new energy multi-station grid-connected system, determining the relation between the active power injected into each station of the new energy and the impedance comprises the following steps:
P 1 ×x 1 ＝P 2 ×x 2 ＝…＝P n ×x n ，
determining any new energy station m as a reference station, and injecting active power P into the new energy station i when low voltage occurs in a new energy multi-station grid-connected system i Comprising:
wherein K is i The ratio coefficient of the new energy station i; p (P) m Active power injected into the new energy station m;
when the low voltage of the new energy multi-station grid-connected system is determined, the transverse component of the voltage drop between the new energy station m and the power supply potential of the alternating current system comprises the following components:
wherein δU is m Is the transverse component of voltage drop between the station grid-connected point and the equivalent potential of the alternating current system, I m Injecting a system current for station m; x is x m Equivalent impedance from the point of the new energy station m to the public connection point is obtained; x is the equivalent impedance of the alternating current system seen from the public connection point; u (U) m The voltage of the grid-connected point of the new energy station m is calculated;
substituting the scaling factor into a formula of a transverse component of a voltage drop between the new energy station m and an equivalent potential of the alternating current system, determining a second low voltage mathematical model, comprising:
wherein S is ac,m And the short-circuit capacity of the new energy station m grid-connected point is obtained.
Preferably, when the new energy multi-station grid-connected system generates low voltage, the relation between the active power injected by the new energy station i and grid-connected point voltage, equivalent power supply potential of an alternating current system and short circuit capacity is as follows:
wherein P is m Active power injected into the new energy station m; um is the voltage of the grid-connected point of the new energy station m; e is equivalent potential of an alternating current system; k (K) i The ratio coefficient of the new energy station i; p (P) i Active power injected into the new energy station i; s is S ac,m Short-circuit capacity of the new energy station m grid-connected point; s is S ac Short circuit capacity provided for an ac system at a common connection point.
Preferably, the determining, according to the second low-voltage mathematical model, the limit access scale of each new energy station in the target new energy multi-station grid-connected system based on the low-voltage limit includes:
wherein,,
wherein P is m-max Maximum injection active power for new energy station m, P i-max Injecting active power for the maximum of the new energy station i; s is S i-max And the limited access scale of the new energy station i is used.
Preferably, determining, according to the second low-voltage mathematical model, a limit short-circuit capacity required to be provided by an ac system in the running new energy multi-station grid-connected system includes:
S ac-min ＝max(S ac-min,m )，m＝1,2,...,n，
wherein S is ac-min For minimum short-circuit capacity of system, S ac-min,m For the short-circuit capacity at the grid-connected point when each new energy station is taken as a reference station, n is the total number of new energy units.
According to yet another aspect of the present invention, there is provided a system for determining a limit access scale of a new energy station, comprising:
the first model building unit is used for building a first low-voltage mathematical model of the grid-connected point of the new energy single-station when the grid-connected system of the new energy single-station generates low voltage;
the second model building unit is used for building a second low-voltage mathematical model of each new energy station grid-connected point when the new energy multi-station grid-connected system generates low voltage based on the first low-voltage mathematical model;
and the limit access scale determining unit is used for determining the limit access scale of each new energy station in the target new energy multi-station grid-connected system based on the low voltage limit according to the second low voltage mathematical model.
According to yet another aspect of the present invention, there is provided a system for determining an ac system limit short-circuit capacity in a new energy multi-station grid-connected system, the system comprising:
The first model building unit is used for building a first low-voltage mathematical model of the new energy single-station grid-connected point when the new energy single-station grid-connected system generates low voltage;
the second model building unit is used for building a second low-voltage mathematical model of each new energy station grid-connected point when the new energy multi-station grid-connected system generates low voltage based on the first low-voltage mathematical model;
and the limit short-circuit capacity determining unit is used for determining the limit short-circuit capacity required to be provided by the alternating current system in the running new energy multi-station grid-connected system according to the second low-voltage mathematical model.
Preferably, the first model building unit builds a first low-voltage mathematical model of the new energy single-station grid-connected point when the new energy single-station grid-connected system generates low voltage, including:
determining short circuit capacity at a grid-connected point in a new energy single-station grid-connected system comprises the following steps:
wherein S is ac 1 is the short-circuit capacity, x of the new energy single-station grid-connected point in the new energy single-station grid-connected system 1 The impedance between the new energy single-station grid-connected point and the common connection point of the alternating current system is shown as x, and the equivalent impedance of the alternating current system is shown as seen from the common connection point;
when determining that the grid-connected system of the new energy single-station generates low voltage, the current flowing into the alternating current system by the new energy single-station comprises the following steps:
Wherein I is 1 The method comprises the steps that output current flowing to a public connection point for a new energy single-station grid connection point is I, current flowing to an alternating current system from the public connection point is U 1 The voltage of the grid-connected point of the single station of the new energy source, P 1 When low voltage appears for the new energy single-station grid-connected system, the active power sent by the new energy single-station;
when the low voltage of the new energy single-station system occurs, the transverse component of the voltage drop between the voltage of the public connection point and the equivalent potential of the alternating current system is determined, and the method comprises the following steps:
wherein δU is 0 Is the transverse component of voltage drop between the public connection point and the equivalent power supply potential of the alternating current system, U 0 E is the equivalent power supply potential of the alternating current system;
when the low voltage of the new energy single-station grid-connected system is determined, the relation between the voltage drop transverse component of the new energy single-station grid-connected point and the voltage of the new energy injection active power, the grid-connected point and the short circuit capacity is determined, so that the first low voltage mathematical model of the new energy single-station grid-connected point is established, and the method comprises the following steps:
wherein δU is 1 Is the transverse component of the voltage drop between the station grid-connected point and the equivalent mains potential of the ac system.
Preferably, the second model building unit builds a second low-voltage mathematical model of each new energy station grid-connected point when the new energy multi-station grid-connected system generates low voltage based on the first low-voltage mathematical model, and the second low-voltage mathematical model comprises:
Determining the relation between the injected active power and the installed capacity of the new energy multi-station grid-connected system at low voltage, wherein the method comprises the following steps:
P i ＝n i S i ，
wherein P is i Is a new energy station i Active power injected into point of connection, S i For the installed capacity of the new energy station i, n i The power factor of the new energy station i;
determining short-circuit capacity at a grid-connected point of a new energy station i comprises the following steps:
wherein S is ac,i Short-circuit capacity of the grid-connected point access of the new energy station i; x is x i Equivalent impedance from the point of the new energy station i to the public connection point is obtained; x is the equivalent impedance of the alternating current system seen from the public connection point;
according to S ac,i Determining equivalent impedance x from grid-connected point to public connection point of new energy field station i i Comprising:
wherein S is ac Short circuit capacity provided for an ac system at a common connection point.
When determining that low voltage occurs in the new energy multi-station grid-connected system, and when the voltage of each grid-connected point reaches a low voltage limit value, the current sent out by the new energy station i comprises the following steps:
wherein I is i The current is sent out for the new energy station i; p (P) i Active power of the new energy station i; u (U) i The grid-connected point voltage of the new energy station i is set;
when low voltage occurs in the new energy multi-station grid-connected system, determining the transverse component of voltage drop between the grid-connected points and the public connection points of each new energy station comprises the following steps:
I 1 ×x 1 ＝I 2 ×x 2 ＝…＝I n ×x n ，1≤i≤n；
When low voltage occurs in the new energy multi-station grid-connected system, determining the relation between the active power injected into each station of the new energy and the impedance comprises the following steps:
P 1 ×x 1 ＝P 2 ×x 2 ＝…＝P n ×x n ，
determining any new energy station m as a reference station, and injecting active power P into the new energy station i when low voltage occurs in a new energy multi-station grid-connected system i Comprising:
wherein K is i The ratio coefficient of the new energy station i; p (P) m Active power injected into the new energy station m;
when the low voltage of the new energy multi-station grid-connected system is determined, the transverse component of the voltage drop between the new energy station m and the power supply potential of the alternating current system comprises the following components:
wherein δU is m Is the transverse component of voltage drop between the station grid-connected point and the equivalent potential of the alternating current system, I m Injecting a system current for station m; x is x m Equivalent impedance from the point of the new energy station m to the public connection point is obtained; x is from publicThe equivalent impedance of the alternating current system seen by the connection point; u (U) m The voltage of the grid-connected point of the new energy station m is calculated;
substituting the scaling factor into a formula of a transverse component of a voltage drop between the new energy station m and an equivalent potential of the alternating current system, determining a second low voltage mathematical model, comprising:
wherein S is ac,m And the short-circuit capacity of the new energy station m grid-connected point is obtained.
Preferably, when the new energy multi-station grid-connected system generates low voltage, the relation between the active power injected by the new energy station i and grid-connected point voltage, equivalent power supply potential of an alternating current system and short circuit capacity is as follows:
Wherein P is m Active power injected into the new energy station m; um is the voltage of the grid-connected point of the new energy station m; e is equivalent potential of an alternating current system; k (K) i The ratio coefficient of the new energy station i; p (P) i Active power injected into the new energy station i; s is S ac,m Short-circuit capacity of the new energy station m grid-connected point; s is S ac Short circuit capacity provided for an ac system at a common connection point.
Preferably, the limit access scale determining unit determines, according to the second low-voltage mathematical model, a limit access scale of each new energy station in the target new energy multi-station grid-connected system based on low-voltage limitation, including:
wherein,,
wherein P is m-max Maximum injection active power for new energy station m, P i-max Injecting active power for the maximum of the new energy station i; s is S i-max And the limited access scale of the new energy station i is used.
Preferably, the determining unit for determining the limit short-circuit capacity determines, according to the second low-voltage mathematical model, the limit short-circuit capacity that needs to be provided by an ac system in the running new energy multi-station grid-connected system, including:
S ac-min ＝max(S ac-min,m )，m＝1,2,...,n，
wherein S is ac-min For minimum short-circuit capacity of system, S ac-min,m For the short-circuit capacity at the grid-connected point when each new energy station is taken as a reference station, n is the total number of new energy units.
The invention provides a method and a system for determining the limit access scale of a new energy station and the limit short-circuit capacity of an alternating current system in a new energy multi-station grid-connected system, which can more intuitively and simply analyze the relationship between the access scale of the new energy station and low voltage, and provide requirements on the short-circuit capacity of the system.
Drawings
Fig. 1 is a flowchart of a method 100 of determining a limit access scale of a new energy station according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a first low voltage model of a new energy single station system according to an embodiment of the present invention;
fig. 3 is a schematic diagram of a new energy multi-station system according to an embodiment of the present invention;
fig. 4 is a schematic structural diagram of a system 400 for determining a limit access scale of a new energy station according to an embodiment of the present invention;
FIG. 5 is a flow chart of a method 500 for determining the limit short circuit capacity of an AC system in a new energy multi-station grid-connected system according to an embodiment of the present invention;
fig. 6 is a schematic structural diagram of a system 600 for determining an ac system limit short-circuit capacity in a new energy multi-station grid-connected system according to an embodiment of the present invention.
Detailed Description
The exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, however, the present invention may be embodied in many different forms and is not limited to the examples described herein, which are provided to fully and completely disclose the present invention and fully convey the scope of the invention to those skilled in the art. The terminology used in the exemplary embodiments illustrated in the accompanying drawings is not intended to be limiting of the invention. In the drawings, like elements/components are referred to by like reference numerals.
Unless otherwise indicated, terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art. In addition, it will be understood that terms defined in commonly used dictionaries should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense.
Fig. 1 is a flowchart of a method 100 of determining a limit access scale of a new energy station according to an embodiment of the present invention. As shown in fig. 1, the method for determining the limit access scale of the new energy station provided by the embodiment of the invention can analyze the relationship between the access scale and the low voltage of the new energy station more intuitively and simply, and has the characteristics of accuracy and rapidness, is simple and practical, and has great significance in ensuring accurate analysis and evaluation of the access scale and the operation scale of the new energy. The method 100 for determining the limit access scale of the new energy station provided by the embodiment of the invention starts from step 101, and establishes a first low-voltage mathematical model of the new energy single station grid-connected point in step 101 when the new energy single station grid-connected system generates low voltage.
Preferably, the establishing a first low-voltage mathematical model of the new energy single-station grid-connected point when the new energy single-station grid-connected system generates low voltage includes:
determining short circuit capacity at a grid-connected point in a new energy single-station grid-connected system comprises the following steps:
wherein S is ac 1 is the short-circuit capacity, x of the new energy single-station grid-connected point in the new energy single-station grid-connected system 1 The impedance between the new energy single-station grid-connected point and the common connection point of the alternating current system is shown as x, and the equivalent impedance of the alternating current system is shown as seen from the common connection point;
when determining that the grid-connected system of the new energy single-station generates low voltage, the current flowing into the alternating current system by the new energy single-station comprises the following steps:
wherein I is 1 The method comprises the steps that output current flowing to a public connection point for a new energy single-station grid connection point is I, current flowing to an alternating current system from the public connection point is U 1 The voltage of the grid-connected point of the single station of the new energy source, P 1 When low voltage appears for the new energy single-station grid-connected system, the active power sent by the new energy single-station;
when the low voltage of the new energy single-station system occurs, the transverse component of the voltage drop between the voltage of the public connection point and the equivalent potential of the alternating current system is determined, and the method comprises the following steps:
wherein δU is 0 Is the transverse component of voltage drop between the public connection point and the equivalent power supply potential of the alternating current system, U 0 For common junction voltage, E for AC system, etcA value power supply potential;
when the low voltage of the new energy single-station grid-connected system is determined, the relation between the voltage drop transverse component of the new energy single-station grid-connected point and the voltage of the new energy injection active power, the grid-connected point and the short circuit capacity is determined, so that the first low voltage mathematical model of the new energy single-station grid-connected point is established, and the method comprises the following steps:
wherein δU is 1 Is the transverse component of the voltage drop between the station grid-connected point and the equivalent mains potential of the ac system.
In step 102, a second low-voltage mathematical model of each new energy station grid-connected point is built based on the first low-voltage mathematical model when the new energy multi-station grid-connected system generates low voltage.
Preferably, when the new energy multi-station grid-connected system generates low voltage, the first low voltage mathematical model is used to build a second low voltage mathematical model of each new energy station grid-connected point, and the new energy multi-station structure is shown in fig. 3, including:
determining the relation between the injected active power and the installed capacity of the new energy multi-station grid-connected system at low voltage, wherein the method comprises the following steps:
P i ＝n i S i ，
wherein P is i Active power of the grid-connected point is injected for the new energy station i, S i For the installed capacity of the new energy station i, n i The power factor of the new energy station i;
determining short-circuit capacity at a grid-connected point of a new energy station i comprises the following steps:
wherein S is ac,i Short-circuit capacity of the grid-connected point access of the new energy station i; x is x i Connecting point to public connection point for new energy station iEquivalent impedance of (a); x is the equivalent impedance of the alternating current system seen from the public connection point;
according to S ac,i Determining equivalent impedance x from grid-connected point to public connection point of new energy field station i i Comprising:
wherein S is ac Short circuit capacity provided for an ac system at a common connection point.
When determining that low voltage occurs in the new energy multi-station grid-connected system, and when the voltage of each grid-connected point reaches a low voltage limit value, the current sent out by the new energy station i comprises the following steps:
wherein I is i The current is sent out for the new energy station i; p (P) i Active power of the new energy station i; u (U) i The grid-connected point voltage of the new energy station i is set;
when low voltage occurs in the new energy multi-station grid-connected system, determining the transverse component of voltage drop between the grid-connected points and the public connection points of each new energy station comprises the following steps:
I 1 ×x 1 ＝I 2 ×x 2 ＝…＝I n ×x n ，1≤i≤n；
when low voltage occurs in the new energy multi-station grid-connected system, determining the relation between the active power injected into each station of the new energy and the impedance comprises the following steps:
P 1 ×x 1 ＝P 2 ×x 2 ＝…＝P n ×x n ，
Determining any new energy station m as a reference station, and injecting active power P into the new energy station i when low voltage occurs in a new energy multi-station grid-connected system i Comprising:
wherein K is i The ratio coefficient of the new energy station i; p (P) m Active power injected into the new energy station m;
when the low voltage of the new energy multi-station grid-connected system is determined, the transverse component of the voltage drop between the new energy station m and the power supply potential of the alternating current system comprises the following components:
wherein δU is m Is the transverse component of voltage drop between the station grid-connected point and the equivalent potential of the alternating current system, I m Injecting a system current for station m; x is x m Equivalent impedance from the point of the new energy station m to the public connection point is obtained; x is the equivalent impedance of the alternating current system seen from the public connection point; u (U) m The voltage of the grid-connected point of the new energy station m is calculated;
substituting the scaling factor into a formula of a transverse component of a voltage drop between the new energy station m and an equivalent potential of the alternating current system, determining a second low voltage mathematical model, comprising:
wherein S is ac,m And the short-circuit capacity of the new energy station m grid-connected point is obtained.
Preferably, when the new energy multi-station grid-connected system generates low voltage, the relation between the active power injected by the new energy station i and grid-connected point voltage, equivalent power supply potential of an alternating current system and short circuit capacity is as follows:
Wherein P is m Active power injected into the new energy station m; um is the voltage of the grid-connected point of the new energy station m; e is equivalent potential of an alternating current system; k (K) i The ratio coefficient of the new energy station i; p (P) i Active power injected into the new energy station i; s is S ac,m Short-circuit capacity of the new energy station m grid-connected point; s is S ac Short circuit capacity provided for an ac system at a common connection point.
In step 103, determining the limit access scale of each new energy station in the target new energy multi-station grid-connected system based on the low voltage limit according to the second low voltage mathematical model.
Preferably, the determining the limit access scale of each new energy station in the target new energy multi-station grid-connected system based on the low voltage limit according to the second low voltage mathematical model includes:
wherein,,
wherein P is m-max Maximum injection active power for new energy station m, P i-max Injecting active power for the maximum of the new energy station i; si (Si) -max And the limited access scale of the new energy station i is used.
The invention is further illustrated by the following examples:
an embodiment includes:
(1) Establishing a low-voltage mathematical model and a basic assumption of the new energy single-station system according to the safe and stable operation requirements and characteristics of the power system;
(2) Deducing the mathematics in the step (1) to a new energy multi-station system, and establishing a low-voltage mathematical model of each station grid-connected point of the new energy multi-station system;
(3) Limiting low voltage in the low-voltage mathematical model of the multi-station system in the step (2), and establishing a new energy access scale mathematical model;
(4) And (3) establishing an alternating current system limit short-circuit capacity mathematical model under the condition that the new energy access scale is fixed according to the new energy access scale mathematical model in the step (3).
Specifically, reasonable assumption is made according to the safe and stable operation requirement and characteristics of the power system:
as shown in fig. 2, the ac system is an infinite system, simplifying the analysis process with reasonable assumptions.
The equivalent power supply potential of the alternating current system is constant;
under the condition of unit voltage, the short-circuit capacity provided by the AC system to the grid-connected point is equal to the admittance value of the system in value, namely the reciprocal of the Thevenin equivalent impedance of the AC system;
when low voltage occurs, the new energy source does not provide reactive power q=0 to the ac system;
the reactance of the alternating current system is far greater than that of the resistor, the resistor is negligible, and r=0;
the initial voltages of all the station's grid-connected points are equal,
when low voltage occurs, the parallel network point of each new energy station is equal to the transverse component of the voltage drop between the equivalent power source potential of the alternating current system, namely delta U 1 ＝δU 2 ＝…＝δU n ，
Wherein the short circuit capacity provided by the alternating current system to the public connection point is as follows:
wherein S is ac Is short circuit capacity; x is the equivalent impedance of the ac system as seen from the common connection point.
In the new energy single-station grid-connected system, the short circuit capacity at the grid-connected point comprises the following steps:
wherein S is ac 1 is the short-circuit capacity, x of the new energy single-station grid-connected point in the new energy single-station grid-connected system 1 The impedance between the new energy single-station grid-connected point and the common connection point of the alternating current system is shown as x, and the equivalent impedance of the alternating current system is shown as seen from the common connection point;
when the grid-connected system of the new energy single-station generates low voltage, the new energy single-station flows into the current of the alternating current system, and the method comprises the following steps:
wherein I is 1 The method comprises the steps that output current flowing to a public connection point for a new energy single-station grid connection point is I, current flowing to an alternating current system from the public connection point is U 1 The voltage of the grid-connected point of the single station of the new energy source, P 1 When low voltage appears for the new energy single-station grid-connected system, the active power sent by the new energy single-station;
when the new energy single-station system generates low voltage, the transverse component of voltage drop between the voltage of the public connection point and the equivalent potential of the alternating current system comprises the following components:
wherein δU is 0 Is the transverse component of voltage drop between the public connection point and the equivalent power supply potential of the alternating current system, U 0 E is the equivalent power supply potential of the alternating current system;
when the new energy single-station grid-connected system generates low voltage, the relation between the voltage drop transverse component of the new energy single-station grid-connected point and the voltage of the new energy injection active power, the grid-connected point and the short circuit capacity comprises the following steps:
wherein δU is 1 Is the transverse component of the voltage drop between the station grid-connected point and the equivalent mains potential of the ac system.
When the energy single-station grid-connected system generates low voltage, the relation between the voltage drop transverse component of the new energy single-station grid-connected point and the voltage of the new energy injection active power, the grid-connected point and the short circuit capacity is established, a first low-voltage mathematical model of the new energy single-station grid-connected point is established, and the method comprises the following steps:
the relation between the injected active power and the installed capacity of the new energy multi-station grid-connected system under low voltage comprises the following steps:
P i ＝n i S i
wherein, let P i Active power of the grid-connected point is injected for the new energy station i, S i For the installed capacity of the new energy station i, n i The power factor of the new energy station i;
wherein, the short circuit capacity at new energy station point i includes:
S ac,i short-circuit capacity at the access point of the new energy station grid-connected point i; x is x i Equivalent impedance from the new energy station grid point i to the public connection point; x is the equivalent impedance of the ac system as seen from the common connection point.
Wherein, according to S aci, Determining equivalent impedance x from new energy station grid point i to public connection point i The formula is as follows:
when low voltage occurs in the new energy multi-station grid-connected system, and when the voltage of each grid-connected point reaches a low voltage limit value, the current sent out by the new energy station i comprises the following components:
wherein I is i Send out current for station i; p (P) i Active power for station i; u (U) i And (5) the grid-connected point voltage of the station i.
When low voltage occurs in the new energy multi-station grid-connected system, a transverse component of voltage drop between each station grid-connected point and a public connection point of the new energy comprises the following components:
I 1 ×x 1 ＝I 2 ×x 2 ＝…＝I n ×x n
when low voltage occurs in the new energy multi-station grid-connected system, each station of the new energy injects the relation between active power and impedance, and the method comprises the following steps:
P 1 ×x 1 ＝P 2 ×x 2 ＝…＝P n ×x n
wherein, new energy station m is the reference station, and when new energy multi-station grid-connected system takes place low voltage, the active power that new energy station i injected includes:
wherein,,
wherein K is i Is the proportionality coefficient of the new energy station i.
When the new energy multi-station grid-connected system generates low voltage, a transverse component of voltage drop between the new energy station m and the power supply potential of the alternating current system comprises the following components:
wherein δU is m Is the transverse component of voltage drop between the station grid-connected point and the equivalent potential of the alternating current system, I m Injecting a system current for station m; x is x m Equivalent impedance from the new energy station grid point m to the public connection point; x is the equivalent impedance of the ac system as seen from the common connection point.
Substituting the proportionality coefficient into a new energy multi-station grid-connected system, and determining a new energy station low-voltage mathematical model by using a transverse component formula of voltage drop between a new energy station m and an alternating current system potential when the new energy multi-station grid-connected system generates low voltage, wherein the mathematical model is as follows:
wherein S is ac,m And the short-circuit capacity of the new energy station m grid-connected point is obtained.
When the new energy multi-station grid-connected system generates low voltage, the relation between the active power injected by the new energy station i and grid-connected point voltage, equivalent power supply potential of an alternating current system and short circuit capacity is as follows:
wherein P is m Active power injected into the new energy station m; um is the voltage of the grid-connected point of the new energy station m; e is equivalent potential of an alternating current system; k (K) i The ratio coefficient of the new energy station i; p (P) i Active power injected into the new energy station i; s is S ac,m Short-circuit capacity of the new energy station m grid-connected point; s is S ac Short circuit capacity provided for an ac system at a common connection point.
The technical regulation of the wind power plant access electric power system of GB/T19963-4011 requires that a wind turbine generator can normally operate when the voltage of the grid-connected point of the wind power plant is between 90% and 110% of the nominal voltage, wherein the grid-connected point of the wind power plant is a high-voltage side bus or node of a wind power plant booster station, and the nominal voltage is not lower than 0.9p.u. In order to ensure the safe and stable operation of the system, the limiting voltage is more than 0.9p.u., and the limit access scale of the new energy is determined according to the low-voltage limit:
Wherein,,
P m-max maximum injection active power for new energy station m, P i-max Active power is injected for the maximum of the new energy station i.
Fig. 4 is a schematic structural diagram of a system 400 for determining a limit access scale of a new energy station according to an embodiment of the present invention. As shown in fig. 4, a system 400 for determining a limit access scale of a new energy station according to an embodiment of the present invention includes: a first model establishing unit 401, a second model establishing unit 402, and a limit access scale determining unit 403.
Preferably, the first model building unit 401 is configured to build a first low-voltage mathematical model of the new energy single-site grid-connected point when the new energy single-site grid-connected system generates a low voltage.
Preferably, the first model building unit 401 builds a first low-voltage mathematical model of the new energy single-station grid-connected point when the new energy single-station grid-connected system generates low voltage, including:
determining short circuit capacity at a grid-connected point in a new energy single-station grid-connected system comprises the following steps:
wherein S is ac1 In the grid-connected system of the new energy single station, the short circuit capacity of the grid-connected point of the new energy single station, x 1 The impedance between the new energy single-station grid-connected point and the common connection point of the alternating current system is shown as x, and the equivalent impedance of the alternating current system is shown as seen from the common connection point;
When determining that the grid-connected system of the new energy single-station generates low voltage, the current flowing into the alternating current system by the new energy single-station comprises the following steps:
wherein I is 1 The method comprises the steps that output current flowing to a public connection point for a new energy single-station grid connection point is I, current flowing to an alternating current system from the public connection point is U 1 The voltage of the grid-connected point of the single station of the new energy source, P 1 When low voltage appears for the new energy single-station grid-connected system, the active power sent by the new energy single-station;
when the low voltage of the new energy single-station system occurs, the transverse component of the voltage drop between the voltage of the public connection point and the equivalent potential of the alternating current system is determined, and the method comprises the following steps:
wherein δU is 0 Is the transverse component of voltage drop between the public connection point and the equivalent power supply potential of the alternating current system, U 0 E is the equivalent power supply potential of the alternating current system;
when the low voltage of the new energy single-station grid-connected system is determined, the relation between the voltage drop transverse component of the new energy single-station grid-connected point and the voltage of the new energy injection active power, the grid-connected point and the short circuit capacity is determined, so that the first low voltage mathematical model of the new energy single-station grid-connected point is established, and the method comprises the following steps:
wherein δU is 1 Is the transverse component of the voltage drop between the station grid-connected point and the equivalent mains potential of the ac system.
Preferably, the second model building unit 402 is configured to build a second low-voltage mathematical model of each new energy substation grid-connected point when the new energy substation grid-connected system generates a low voltage based on the first low-voltage mathematical model.
Preferably, the second model building unit 402 builds a second low-voltage mathematical model of each new energy station grid-connected point when the new energy multi-station grid-connected system generates a low voltage based on the first low-voltage mathematical model, including:
determining the relation between the injected active power and the installed capacity of the new energy multi-station grid-connected system at low voltage, wherein the method comprises the following steps:
P i ＝n i S i ，
wherein P is i Active power of the grid-connected point is injected for the new energy station i, S i For the installed capacity of the new energy station i, n i The power factor of the new energy station i;
determining short-circuit capacity at a grid-connected point of a new energy station i comprises the following steps:
wherein S is ac,i Short-circuit capacity of the grid-connected point access of the new energy station i; x is x i Equivalent impedance from the point of the new energy station i to the public connection point is obtained; x is the equivalent impedance of the alternating current system seen from the public connection point;
according to S ac,i Determining equivalent impedance x from grid-connected point to public connection point of new energy field station i i Comprising:
wherein S is ac Short circuit capacity provided for an ac system at a common connection point.
When determining that low voltage occurs in the new energy multi-station grid-connected system, and when the voltage of each grid-connected point reaches a low voltage limit value, the current sent out by the new energy station i comprises the following steps:
wherein I is i The current is sent out for the new energy station i; p (P) i Active power of the new energy station i; u (U) i The grid-connected point voltage of the new energy station i is set;
when low voltage occurs in the new energy multi-station grid-connected system, determining the transverse component of voltage drop between the grid-connected points and the public connection points of each new energy station comprises the following steps:
I 1 ×x 1 ＝I 2 ×x 2 ＝…＝I n ×x n ，1≤i≤n；
when low voltage occurs in the new energy multi-station grid-connected system, determining the relation between the active power injected into each station of the new energy and the impedance comprises the following steps:
P 1 ×x 1 ＝P 2 ×x 2 ＝…＝P n ×x n ，
determining any new energy station m as a reference station, and injecting active power P into the new energy station i when low voltage occurs in a new energy multi-station grid-connected system i Comprising:
wherein K is i The ratio coefficient of the new energy station i; p (P) m Active power injected into the new energy station m;
when the low voltage of the new energy multi-station grid-connected system is determined, the transverse component of the voltage drop between the new energy station m and the power supply potential of the alternating current system comprises the following components:
Wherein δU is m Is the transverse component of voltage drop between the station grid-connected point and the equivalent potential of the alternating current system, I m Injecting a system current for station m; x is x m Equivalent impedance from the point of the new energy station m to the public connection point is obtained; x is the equivalent impedance of the alternating current system seen from the public connection point; u (U) m The voltage of the grid-connected point of the new energy station m is calculated;
substituting the scaling factor into a formula of a transverse component of a voltage drop between the new energy station m and an equivalent potential of the alternating current system, determining a second low voltage mathematical model, comprising:
wherein S is ac,m And the short-circuit capacity of the new energy station m grid-connected point is obtained.
Preferably, when the low voltage of the new energy multi-station grid-connected system is determined, the relation between the active power injected by the new energy station i and the grid-connected point voltage, the equivalent power supply potential of the alternating current system and the short circuit capacity is as follows:
wherein P is m Active power injected into the new energy station m; um is the voltage of the grid-connected point of the new energy station m; e is equivalent potential of an alternating current system; k (K) i The ratio coefficient of the new energy station i; p (P) i Active power injected into the new energy station i; s is S ac,m Short-circuit capacity of the new energy station m grid-connected point; s is S ac Short circuit for AC system at public connection pointCapacity.
Preferably, the limit access scale determining unit 403 is configured to determine, according to the second low voltage mathematical model, a limit access scale of each new energy station in the target new energy multi-station grid-connected system based on a low voltage limitation.
Preferably, the limit access scale determining unit 403 determines, according to the second low voltage mathematical model, a limit access scale of each new energy station in the target new energy multi-station grid-connected system based on a low voltage limit, including:
wherein,,
wherein P is m-max Maximum injection active power for new energy station m, P i-max Injecting active power for the maximum of the new energy station i; s is S i-max And the limited access scale of the new energy station i is used.
The system 400 for determining the limit access scale of the new energy station according to the embodiment of the present invention corresponds to the method 100 for determining the limit access scale of the new energy station according to another embodiment of the present invention, and will not be described herein.
Fig. 5 is a method 500 for determining an ac system limit short circuit capacity in a new energy multi-station grid-connected system according to an embodiment of the present invention. As shown in fig. 5, a method 500 for determining an ac system limit short-circuit capacity in a new energy multi-station grid-connected system according to an embodiment of the present invention starts from step 501, and establishes a first low-voltage mathematical model of a new energy single-station grid-connected point in step 501 when a low voltage occurs in the new energy single-station grid-connected system.
In step 502, a second low-voltage mathematical model of each new energy station grid-connected point is built based on the first low-voltage mathematical model when the new energy multi-station grid-connected system generates low voltage.
In step 503, according to the second low-voltage mathematical model, the limit short-circuit capacity that needs to be provided by the ac system in the running new energy multi-station grid-connected system is determined.
In this embodiment, step 501 and step 502 are the same as step 101 and step 102 of the previous embodiment, respectively, and are not described herein.
Preferably, the determining, according to the second low-voltage mathematical model, a limit short-circuit capacity that needs to be provided by an ac system in the running new energy multi-station grid-connected system includes:
S ac-min ＝max(S ac-min,m )，m＝1,2,...,n，
wherein S is ac-min For minimum short-circuit capacity of system, S ac-min,m For the short-circuit capacity at the grid-connected point when each new energy station is taken as a reference station, n is the total number of new energy units.
In the invention, when determining that the new energy multi-station grid-connected system generates low voltage, after determining the relation between the active power injected by the new energy station i and the grid-connected point voltage, the equivalent power supply potential of the alternating current system and the short-circuit capacity, determining the limit short-circuit capacity required to be provided by the alternating current system in the running new energy multi-station grid-connected system according to the second low voltage mathematical model, the method comprises the following steps:
S ac-min ＝max(S ac-min,m )，m＝1,2,...,n，
wherein S is ac-min For minimum short-circuit capacity of system, S ac-min,m For the short-circuit capacity at the grid-connected point when each new energy station is taken as a reference station, n is the total number of new energy units.
Fig. 6 is a schematic structural diagram of a system 600 for determining an ac system limit short-circuit capacity in a new energy multi-station grid-connected system according to an embodiment of the present invention. As shown in fig. 6, a system 600 for determining an ac system limit short-circuit capacity in a new energy multi-station grid-connected system according to an embodiment of the present invention includes: a first model building unit 601, a second model building unit 602, and a limit short circuit capacity determining unit 603.
Preferably, the first model building unit 601 is configured to build a first low-voltage mathematical model of the new energy single-site grid-connected point when the new energy single-site grid-connected system generates a low voltage.
Preferably, the second model building unit 602 is configured to build a second low-voltage mathematical model of each new energy substation grid-connected point when the new energy substation grid-connected system generates a low voltage based on the first low-voltage mathematical model.
Preferably, the limit short-circuit capacity determining unit 603 is configured to determine, according to the second low-voltage mathematical model, a limit short-circuit capacity that needs to be provided by an ac system in the running new energy multi-station grid-connected system.
Preferably, the determining unit 603 for determining, according to the second low voltage mathematical model, the limit short-circuit capacity that needs to be provided by the ac system in the running new energy multi-station grid-connected system includes:
S ac-min ＝max(S ac-min,m )，m＝1,2,...,n，
Wherein S is ac-min For minimum short-circuit capacity of system, S ac-min,m For the short-circuit capacity at the grid-connected point when each new energy station is taken as a reference station, n is the total number of new energy units.
The first model building unit 601 and the second model building unit 602 of the present embodiment are the same as the first model building unit 401 and the second model building unit 402 of the previous embodiment, respectively, and are not described herein again.
The system 600 for determining the limit short-circuit capacity of the ac system in the new energy multi-station grid-connected system according to the embodiment of the present invention corresponds to the method 500 for determining the limit short-circuit capacity of the ac system in the new energy multi-station grid-connected system according to another embodiment of the present invention, and is not described herein.
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 solutions in the embodiments of the present application may be implemented in various computer languages, for example, object-oriented programming language Java, and an transliterated scripting language JavaScript, etc.
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.
While preferred embodiments of the present application have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiments and all such alterations and modifications as fall within the scope of the application.
It will be apparent to those skilled in the art that various modifications and variations can be made in the present application without departing from the spirit or scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims and the equivalents thereof, the present application is intended to cover such modifications and variations.

Claims (10)

1. A method of determining a limit access scale for a new energy station, the method comprising:
Establishing a first low-voltage mathematical model of the new energy single-station grid-connected point when the new energy single-station grid-connected system generates low voltage;
establishing a second low-voltage mathematical model of each new energy station grid-connected point when the new energy multi-station grid-connected system generates low voltage based on the first low-voltage mathematical model;
determining the limit access scale of each new energy station in the target new energy multi-station grid-connected system based on low voltage limitation according to the second low voltage mathematical model;
when the new energy single-station grid-connected system generates low voltage, a first low-voltage mathematical model of the new energy single-station grid-connected point is established, and the method comprises the following steps:
determining short circuit capacity at a grid-connected point in a new energy single-station grid-connected system comprises the following steps:
wherein S is ac1 In the grid-connected system of the new energy single station, the short circuit capacity of the grid-connected point of the new energy single station, x 1 The impedance between the new energy single-station grid-connected point and the common connection point of the alternating current system is shown as x, and the equivalent impedance of the alternating current system is shown as seen from the common connection point;
when determining that the grid-connected system of the new energy single-station generates low voltage, the current flowing into the alternating current system by the new energy single-station comprises the following steps:
wherein I is 1 The method comprises the steps that output current flowing to a public connection point for a new energy single-station grid connection point is I, current flowing to an alternating current system from the public connection point is U 1 The voltage of the grid-connected point of the single station of the new energy source, P 1 When low voltage appears for the new energy single-station grid-connected system, the active power sent by the new energy single-station;
when the low voltage of the new energy single-station system occurs, the transverse component of the voltage drop between the voltage of the public connection point and the equivalent potential of the alternating current system is determined, and the method comprises the following steps:
wherein δU is 0 Is the transverse component of voltage drop between the public connection point and the equivalent power supply potential of the alternating current system, U 0 E is the equivalent power supply potential of the alternating current system;
when the low voltage of the new energy single-station grid-connected system is determined, the relation between the voltage drop transverse component of the new energy single-station grid-connected point and the voltage of the new energy injection active power, the grid-connected point and the short circuit capacity is determined, so that the first low voltage mathematical model of the new energy single-station grid-connected point is established, and the method comprises the following steps:
wherein δU is 1 Is the transverse component of voltage drop between the station grid-connected point and the equivalent power supply potential of the alternating current system;
the establishing a second low-voltage mathematical model of each new energy station grid-connected point when the new energy multi-station grid-connected system generates low voltage based on the first low-voltage mathematical model comprises the following steps:
determining the relation between the injected active power and the installed capacity of the new energy multi-station grid-connected system at low voltage, wherein the method comprises the following steps:
P i ＝n i S i ，
Wherein P is i Active power of the grid-connected point is injected for the new energy station i, S i For the installed capacity of the new energy station i, n i The power factor of the new energy station i;
determining short-circuit capacity at a grid-connected point of a new energy station i comprises the following steps:
wherein S is ac,i Short-circuit capacity of the grid-connected point access of the new energy station i; x is x i Equivalent impedance from the point of the new energy station i to the public connection point is obtained; x is the equivalent impedance of the alternating current system seen from the public connection point;
according to S ac,i Determining equivalent impedance x from grid-connected point to public connection point of new energy field station i i Comprising:
wherein S is ac Short circuit capacity provided for the ac system at the common connection point;
when determining that low voltage occurs in the new energy multi-station grid-connected system, and when the voltage of each grid-connected point reaches a low voltage limit value, the current sent out by the new energy station i comprises the following steps:
wherein I is i The current is sent out for the new energy station i; p (P) i Active power of the new energy station i; u (U) i The grid-connected point voltage of the new energy station i is set;
when low voltage occurs in the new energy multi-station grid-connected system, determining the transverse component of voltage drop between the grid-connected points and the public connection points of each new energy station comprises the following steps:
I 1 ×x 1 ＝I 2 ×x 2 ＝…＝I n ×x n ，1≤i≤n；
when low voltage occurs in the new energy multi-station grid-connected system, determining the relation between the active power injected into each station of the new energy and the impedance comprises the following steps:
P 1 ×x 1 ＝P 2 ×x 2 ＝…＝P n ×x n ，
Determining any new energy station m as a reference station, and injecting active power P into the new energy station i when low voltage occurs in a new energy multi-station grid-connected system i Comprising:
wherein K is i The ratio coefficient of the new energy station i; p (P) m Active power injected into the new energy station m;
when the low voltage of the new energy multi-station grid-connected system is determined, the transverse component of the voltage drop between the new energy station m and the power supply potential of the alternating current system comprises the following components:
wherein δU is m Is the transverse component of voltage drop between the station grid-connected point and the equivalent potential of the alternating current system, I m Injecting a system current for station m; x is x m Equivalent impedance from the point of the new energy station m to the public connection point is obtained; x is the equivalent impedance of the alternating current system seen from the public connection point; u (U) m The voltage of the grid-connected point of the new energy station m is calculated;
substituting the scaling factor into a formula of a transverse component of a voltage drop between the new energy station m and an equivalent potential of the alternating current system, determining a second low voltage mathematical model, comprising:
wherein S is ac,m And the short-circuit capacity of the new energy station m grid-connected point is obtained.
2. A method for determining an ac system limit short circuit capacity in a new energy multi-station grid-connected system, the method comprising:
establishing a first low-voltage mathematical model of the new energy single-station grid-connected point when the new energy single-station grid-connected system generates low voltage;
Establishing a second low-voltage mathematical model of each new energy station grid-connected point when the new energy multi-station grid-connected system generates low voltage based on the first low-voltage mathematical model;
determining the limit short-circuit capacity required to be provided by an alternating current system in the running new energy multi-station grid-connected system according to the second low-voltage mathematical model;
when the new energy single-station grid-connected system generates low voltage, a first low-voltage mathematical model of the new energy single-station grid-connected point is established, and the method comprises the following steps:
determining short circuit capacity at a grid-connected point in a new energy single-station grid-connected system comprises the following steps:
wherein S is ac1 In the grid-connected system of the new energy single station, the short circuit capacity of the grid-connected point of the new energy single station, x 1 The impedance between the new energy single-station grid-connected point and the common connection point of the alternating current system is shown as x, and the equivalent impedance of the alternating current system is shown as seen from the common connection point;
when determining that the grid-connected system of the new energy single-station generates low voltage, the current flowing into the alternating current system by the new energy single-station comprises the following steps:
wherein I is 1 The method comprises the steps that output current flowing to a public connection point for a new energy single-station grid connection point is I, current flowing to an alternating current system from the public connection point is U 1 The voltage of the grid-connected point of the single station of the new energy source, P 1 When low voltage appears for the new energy single-station grid-connected system, the active power sent by the new energy single-station;
when the low voltage of the new energy single-station system occurs, the transverse component of the voltage drop between the voltage of the public connection point and the equivalent potential of the alternating current system is determined, and the method comprises the following steps:
wherein δU is 0 Is the transverse component of voltage drop between the public connection point and the equivalent power supply potential of the alternating current system, U 0 E is the equivalent power supply potential of the alternating current system;
when the low voltage of the new energy single-station grid-connected system is determined, the relation between the voltage drop transverse component of the new energy single-station grid-connected point and the voltage of the new energy injection active power, the grid-connected point and the short circuit capacity is determined, so that the first low voltage mathematical model of the new energy single-station grid-connected point is established, and the method comprises the following steps:
wherein δU is 1 Is the transverse component of voltage drop between the station grid-connected point and the equivalent power supply potential of the alternating current system;
the establishing a second low-voltage mathematical model of each new energy station grid-connected point when the new energy multi-station grid-connected system generates low voltage based on the first low-voltage mathematical model comprises the following steps:
determining the relation between the injected active power and the installed capacity of the new energy multi-station grid-connected system at low voltage, wherein the method comprises the following steps:
P i ＝n i S i ，
Wherein P is i Active power of the grid-connected point is injected for the new energy station i, S i For the installed capacity of the new energy station i, n i The power factor of the new energy station i;
determining short-circuit capacity at a grid-connected point of a new energy station i comprises the following steps:
wherein S is ac,i Short-circuit capacity of the grid-connected point access of the new energy station i; x is x i Equivalent impedance from the point of the new energy station i to the public connection point is obtained; x is the equivalent impedance of the alternating current system seen from the public connection point;
according to S ac,i Determining equivalent impedance x from grid-connected point to public connection point of new energy field station i i Comprising:
wherein S is ac Short circuit capacity provided for the ac system at the common connection point;
when determining that low voltage occurs in the new energy multi-station grid-connected system, and when the voltage of each grid-connected point reaches a low voltage limit value, the current sent out by the new energy station i comprises the following steps:
wherein I is i The current is sent out for the new energy station i; p (P) i Active power of the new energy station i; u (U) i The grid-connected point voltage of the new energy station i is set;
when low voltage occurs in the new energy multi-station grid-connected system, determining the transverse component of voltage drop between the grid-connected points and the public connection points of each new energy station comprises the following steps:
I 1 ×x 1 ＝I 2 ×x 2 ＝…＝I n ×x n ，1≤i≤n；
when low voltage occurs in the new energy multi-station grid-connected system, determining the relation between the active power injected into each station of the new energy and the impedance comprises the following steps:
P 1 ×x 1 ＝P 2 ×x 2 ＝…＝P n ×x n ，
Determining any new energy station m as a reference station, and injecting active power P into the new energy station i when low voltage occurs in a new energy multi-station grid-connected system i Comprising:
wherein K is i The ratio coefficient of the new energy station i; p (P) m Active power injected into the new energy station m;
when the low voltage of the new energy multi-station grid-connected system is determined, the transverse component of the voltage drop between the new energy station m and the power supply potential of the alternating current system comprises the following components:
wherein δU is m Is the transverse component of voltage drop between the station grid-connected point and the equivalent potential of the alternating current system, I m Injecting a system current for station m; x is x m Equivalent impedance from the point of the new energy station m to the public connection point is obtained; x is the equivalent impedance of the alternating current system seen from the public connection point; u (U) m The voltage of the grid-connected point of the new energy station m is calculated;
substituting the scaling factor into a formula of a transverse component of a voltage drop between the new energy station m and an equivalent potential of the alternating current system, determining a second low voltage mathematical model, comprising:
wherein S is ac,m And the short-circuit capacity of the new energy station m grid-connected point is obtained.
3. The method according to claim 1 or 2, wherein when the new energy multi-station grid-connected system generates low voltage, the relation between the active power injected by the new energy station i and the grid-connected point voltage, the equivalent power supply potential of the alternating current system and the short-circuit capacity comprises the following steps:
Wherein P is m Active power injected into the new energy station m; um is the voltage of the grid-connected point of the new energy station m; e is equivalent potential of an alternating current system; k (K) i The ratio coefficient of the new energy station i; p (P) i Active power injected into the new energy station i; s is S ac,m Short-circuit capacity of the new energy station m grid-connected point; s is S ac Short circuit capacity provided for an ac system at a common connection point.
4. The method of claim 3, wherein determining the limit access scale for each new energy site in the target new energy multi-site grid-tie system based on the low voltage limit according to the second low voltage mathematical model comprises:
wherein,,
wherein P is m-max Maximum injection active power for new energy station m, P i-max Injecting active power for the maximum of the new energy station i; s is S i-max And the limited access scale of the new energy station i is used.
5. The method according to claim 3, wherein determining, according to the second low-voltage mathematical model, a limit short-circuit capacity that needs to be provided by an ac system in the running new-energy multi-station grid-connected system includes:
S ac-min ＝max(S ac-min,m )，m＝1,2,…,n，
wherein S is ac-min For minimum short-circuit capacity of system, S ac-min,m For short-circuit capacity at grid-connected points when each new energy station m is taken as a reference station, n is the total number of new energy units.
6. A system for determining a limit access scale of a new energy station, the system comprising:
the first model building unit is used for building a first low-voltage mathematical model of the grid-connected point of the new energy single-station when the grid-connected system of the new energy single-station generates low voltage;
the second model building unit is used for building a second low-voltage mathematical model of each new energy station grid-connected point when the new energy multi-station grid-connected system generates low voltage based on the first low-voltage mathematical model;
the limit access scale determining unit is used for determining the limit access scale of each new energy station in the target new energy multi-station grid-connected system based on low voltage limitation according to the second low voltage mathematical model;
the first model building unit builds a first low-voltage mathematical model of the new energy single-station grid-connected point when the new energy single-station grid-connected system generates low voltage, and the first low-voltage mathematical model comprises the following components:
determining short circuit capacity at a grid-connected point in a new energy single-station grid-connected system comprises the following steps:
wherein S is ac1 In the grid-connected system of the new energy single station, the short circuit capacity of the grid-connected point of the new energy single station, x 1 The impedance between the new energy single-station grid-connected point and the common connection point of the alternating current system is shown as x, and the equivalent impedance of the alternating current system is shown as seen from the common connection point;
When determining that the grid-connected system of the new energy single-station generates low voltage, the current flowing into the alternating current system by the new energy single-station comprises the following steps:
wherein I is 1 The method comprises the steps that output current flowing to a public connection point for a new energy single-station grid connection point is I, current flowing to an alternating current system from the public connection point is U 1 The voltage of the grid-connected point of the single station of the new energy source, P 1 When low voltage appears for the new energy single-station grid-connected system, the active power sent by the new energy single-station;
when the low voltage of the new energy single-station system occurs, the transverse component of the voltage drop between the voltage of the public connection point and the equivalent potential of the alternating current system is determined, and the method comprises the following steps:
wherein δU is 0 Is the transverse component of voltage drop between the public connection point and the equivalent power supply potential of the alternating current system, U 0 E is the equivalent power supply potential of the alternating current system;
when the low voltage of the new energy single-station grid-connected system is determined, the relation between the voltage drop transverse component of the new energy single-station grid-connected point and the voltage of the new energy injection active power, the grid-connected point and the short circuit capacity is determined, so that the first low voltage mathematical model of the new energy single-station grid-connected point is established, and the method comprises the following steps:
wherein δU is 1 Is the transverse component of voltage drop between the station grid-connected point and the equivalent power supply potential of the alternating current system;
The second model building unit builds a second low-voltage mathematical model of each new energy station grid-connected point when the new energy multi-station grid-connected system generates low voltage based on the first low-voltage mathematical model, and the second low-voltage mathematical model comprises:
determining the relation between the injected active power and the installed capacity of the new energy multi-station grid-connected system at low voltage, wherein the method comprises the following steps:
P i ＝n i S i ，
wherein P is i Active power of the grid-connected point is injected for the new energy station i, S i For the installed capacity of the new energy station i, n i The power factor of the new energy station i;
determining short-circuit capacity at a grid-connected point of a new energy station i comprises the following steps:
wherein S is ac.i Short-circuit capacity of the grid-connected point access of the new energy station i; x is x i Equivalent impedance from the point of the new energy station i to the public connection point is obtained; x is the equivalent impedance of the alternating current system seen from the public connection point;
according to S ac.i Determining equivalent impedance x from grid-connected point to public connection point of new energy field station i i Comprising:
wherein S is ac Short circuit capacity provided for the ac system at the common connection point;
when determining that low voltage occurs in the new energy multi-station grid-connected system, and when the voltage of each grid-connected point reaches a low voltage limit value, the current sent out by the new energy station i comprises the following steps:
Wherein I is i The current is sent out for the new energy station i; p (P) i Active power of the new energy station i; u (U) i The grid-connected point voltage of the new energy station i is set;
when low voltage occurs in the new energy multi-station grid-connected system, determining the transverse component of voltage drop between the grid-connected points and the public connection points of each new energy station comprises the following steps:
I 1 ×x 1 ＝I 2 ×x 2 ＝…＝I n ×x n ，1≤i≤n；
when low voltage occurs in the new energy multi-station grid-connected system, determining the relation between the active power injected into each station of the new energy and the impedance comprises the following steps:
P 1 ×x 1 ＝P 2 ×x 2 ＝…＝P n ×x n ，
determining any new energyThe source station m is a reference station, and when a new energy multi-station grid-connected system generates low voltage, the new energy station i injects active power P i Comprising:
wherein K is i The ratio coefficient of the new energy station i; p (P) m Active power injected into the new energy station m; when the low voltage of the new energy multi-station grid-connected system is determined, the transverse component of the voltage drop between the new energy station m and the power supply potential of the alternating current system comprises the following components:
wherein δU is m Is the transverse component of voltage drop between the station grid-connected point and the equivalent potential of the alternating current system, I m Injecting a system current for station m; x is x m Equivalent impedance from the point of the new energy station m to the public connection point is obtained; x is the equivalent impedance of the alternating current system seen from the public connection point; u (U) m The voltage of the grid-connected point of the new energy station m is calculated;
substituting the scaling factor into a formula of a transverse component of a voltage drop between the new energy station m and an equivalent potential of the alternating current system, determining a second low voltage mathematical model, comprising:
wherein S is ac,m And the short-circuit capacity of the new energy station m grid-connected point is obtained.
7. A system for determining an ac system limit short circuit capacity in a new energy multi-site grid-tie system, the system comprising:
the first model building unit is used for building a first low-voltage mathematical model of the new energy single-station grid-connected point when the new energy single-station grid-connected system generates low voltage;
the second model building unit is used for building a second low-voltage mathematical model of each new energy station grid-connected point when the new energy multi-station grid-connected system generates low voltage based on the first low-voltage mathematical model;
the limit short-circuit capacity determining unit is used for determining the limit short-circuit capacity required to be provided by an alternating current system in the running new energy multi-station grid-connected system according to the second low-voltage mathematical model;
the first model building unit builds a first low-voltage mathematical model of the new energy single-station grid-connected point when the new energy single-station grid-connected system generates low voltage, and the first low-voltage mathematical model comprises the following components:
Determining short circuit capacity at a grid-connected point in a new energy single-station grid-connected system comprises the following steps:
wherein S is ac1 In the grid-connected system of the new energy single station, the short circuit capacity of the grid-connected point of the new energy single station, x 1 The impedance between the new energy single-station grid-connected point and the common connection point of the alternating current system is shown as x, and the equivalent impedance of the alternating current system is shown as seen from the common connection point;
when determining that the grid-connected system of the new energy single-station generates low voltage, the current flowing into the alternating current system by the new energy single-station comprises the following steps:
wherein I is 1 The method comprises the steps that output current flowing to a public connection point for a new energy single-station grid connection point is I, current flowing to an alternating current system from the public connection point is U 1 The voltage of the grid-connected point of the single station of the new energy source, P 1 Is a new energy billWhen low voltage occurs in the station grid-connected system, active power sent by the new energy single station is generated;
when the low voltage of the new energy single-station system occurs, the transverse component of the voltage drop between the voltage of the public connection point and the equivalent potential of the alternating current system is determined, and the method comprises the following steps:
wherein δU is 0 Is the transverse component of voltage drop between the public connection point and the equivalent power supply potential of the alternating current system, U 0 E is the equivalent power supply potential of the alternating current system;
when the low voltage of the new energy single-station grid-connected system is determined, the relation between the voltage drop transverse component of the new energy single-station grid-connected point and the voltage of the new energy injection active power, the grid-connected point and the short circuit capacity is determined, so that the first low voltage mathematical model of the new energy single-station grid-connected point is established, and the method comprises the following steps:
Wherein δU is 1 Is the transverse component of voltage drop between the station grid-connected point and the equivalent power supply potential of the alternating current system;
the second model building unit builds a second low-voltage mathematical model of each new energy station grid-connected point when the new energy multi-station grid-connected system generates low voltage based on the first low-voltage mathematical model, and the second low-voltage mathematical model comprises:
determining the relation between the injected active power and the installed capacity of the new energy multi-station grid-connected system at low voltage, wherein the method comprises the following steps:
P i ＝n i S i ，
wherein P is i Active power of the grid-connected point is injected for the new energy station i, S i For the installed capacity of the new energy station i, n i The power factor of the new energy station i;
determining short-circuit capacity at a grid-connected point of a new energy station i comprises the following steps:
wherein S is ac.i Short-circuit capacity of the grid-connected point access of the new energy station i; x is x i Equivalent impedance from the point of the new energy station i to the public connection point is obtained; x is the equivalent impedance of the alternating current system seen from the public connection point;
according to S ac.i Determining equivalent impedance x from grid-connected point to public connection point of new energy field station i i Comprising:
wherein S is ac Short circuit capacity provided for the ac system at the common connection point;
when determining that low voltage occurs in the new energy multi-station grid-connected system, and when the voltage of each grid-connected point reaches a low voltage limit value, the current sent out by the new energy station i comprises the following steps:
Wherein I is i The current is sent out for the new energy station i; p (P) i Active power of the new energy station i; u (U) i The grid-connected point voltage of the new energy station i is set;
when low voltage occurs in the new energy multi-station grid-connected system, determining the transverse component of voltage drop between the grid-connected points and the public connection points of each new energy station comprises the following steps:
I 1 ×x 1 ＝I 2 ×x 2 ＝…＝I n ×x n ，1≤i≤n；
when low voltage occurs in the new energy multi-station grid-connected system, determining the relation between the active power injected into each station of the new energy and the impedance comprises the following steps:
P 1 ×x 1 ＝P 2 ×x 2 ＝…＝P n ×x n ，
determining any new energy station m as a reference station, and injecting active power P into the new energy station i when low voltage occurs in a new energy multi-station grid-connected system i Comprising:
wherein K is i The ratio coefficient of the new energy station i; p (P) m Active power injected into the new energy station m; when the low voltage of the new energy multi-station grid-connected system is determined, the transverse component of the voltage drop between the new energy station m and the power supply potential of the alternating current system comprises the following components:
wherein δU is m Is the transverse component of voltage drop between the station grid-connected point and the equivalent potential of the alternating current system, I m Injecting a system current for station m; x is x m Equivalent impedance from the point of the new energy station m to the public connection point is obtained; x is the equivalent impedance of the alternating current system seen from the public connection point; u (U) m The voltage of the grid-connected point of the new energy station m is calculated;
substituting the scaling factor into a formula of a transverse component of a voltage drop between the new energy station m and an equivalent potential of the alternating current system, determining a second low voltage mathematical model, comprising:
wherein S is ac,m And the short-circuit capacity of the new energy station m grid-connected point is obtained.
8. The system according to claim 6 or 7, wherein when the new energy multi-station grid-connected system generates low voltage, the relation between the active power injected by the new energy station i and the grid-connected point voltage, the equivalent power supply potential of the alternating current system and the short-circuit capacity comprises:
wherein P is m Active power injected into the new energy station m; um is the voltage of the grid-connected point of the new energy station m; e is equivalent potential of an alternating current system; k (K) i The ratio coefficient of the new energy station i; p (P) i Active power injected into the new energy station i; s is S ac,m Short-circuit capacity of the new energy station m grid-connected point; s is S ac Short circuit capacity provided for an ac system at a common connection point.
9. The system according to claim 8, wherein the limit access scale determining unit determines the limit access scale of each new energy station in the target new energy multi-station grid-connected system based on the low voltage limit according to the second low voltage mathematical model, comprising:
Wherein P is m-max Maximum injection active power for new energy station m, P i-max Injecting active power for the maximum of the new energy station i; s is S i-max And the limited access scale of the new energy station i is used.
10. The system according to claim 8, wherein the limiting short-circuit capacity determining unit determines, according to the second low-voltage mathematical model, a limiting short-circuit capacity that needs to be provided by an ac system in the running new-energy multi-station grid-connected system, including:
S ac-min ＝max(S ac-min,m )，m＝1,2,…,n，
wherein S is ac-min For minimum short-circuit capacity of system, S ac-min,m For the short-circuit capacity at the grid-connected point when each new energy station is taken as a reference station, n is the total number of new energy units.
CN202110535001.6A 2021-05-17 2021-05-17 Method and system for determining limit access scale and short-circuit capacity of new energy station Active CN113437763B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110535001.6A CN113437763B (en) 2021-05-17 2021-05-17 Method and system for determining limit access scale and short-circuit capacity of new energy station

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110535001.6A CN113437763B (en) 2021-05-17 2021-05-17 Method and system for determining limit access scale and short-circuit capacity of new energy station

Publications (2)

Publication Number Publication Date
CN113437763A CN113437763A (en) 2021-09-24
CN113437763B true CN113437763B (en) 2023-08-01

Family

ID=77802514

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110535001.6A Active CN113437763B (en) 2021-05-17 2021-05-17 Method and system for determining limit access scale and short-circuit capacity of new energy station

Country Status (1)

Country Link
CN (1) CN113437763B (en)

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105098842A (en) * 2015-08-12 2015-11-25 国网山东省电力公司电力科学研究院 Wind farm integration capacity determination method in consideration of voltage constraints

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105098842A (en) * 2015-08-12 2015-11-25 国网山东省电力公司电力科学研究院 Wind farm integration capacity determination method in consideration of voltage constraints

Also Published As

Publication number Publication date
CN113437763A (en) 2021-09-24

Similar Documents

Publication Publication Date Title
CN109586272B (en) Method and system for generating power grid continuous operation simulation section
CN110135039B (en) Method and device for determining three-phase voltage unbalance degree of wind power collection area
CN110212548B (en) Configuration method and device of STATCOM (static synchronous compensator) of multi-DC feed-in receiving end system
CN114676569B (en) Power grid simulation analysis example, and generation method, generation system, equipment and medium thereof
CN115622053A (en) Automatic load modeling method and device for considering distributed power supply
CN113595093B (en) Reactive voltage automatic control method and device for new energy power station and storage medium
CN106356872A (en) Configuration method for static synchronous compensator of ultrahigh-voltage weak-direct-current receiving end power grid
CN113437763B (en) Method and system for determining limit access scale and short-circuit capacity of new energy station
CN112039119B (en) Photovoltaic access-containing power distribution network voltage control method and system
Bhujade et al. Economic analysis of annual load loss due to voltage sags in industrial distribution networks with distributed PVs
CN113241736A (en) Method and system for line protection adaptability analysis of new energy sending
Parihar et al. Power flow analysis of balanced radial distribution system with composite load model
Liu et al. Modeling simulation technology research for distribution network planning
Maya et al. A generalised three phase power flow algorithm incorporating the uncertainty of Photo Voltaic (PV) source for unbalanced distribution network
CN111211581B (en) Method and device for determining new energy acceptance capacity in power system
CN112928773B (en) Method and system for quantifying maximum access scale of new energy
CN113987848A (en) Intelligent load composition identification and accurate load modeling method and system
Cerbantes et al. Optimal power flow with voltage-sensitive loads in distribution networks
CN113346553A (en) Evaluation method and device for output ratio of renewable energy power station
CN113300353A (en) Power grid partition load margin calculation method and device considering N-1 reliability
Sitar et al. The Usage of the Power Load as a Physical Diagram for Electric Vehicle Charging Modelling
CN110718912B (en) Method and device for determining optimal electrical distance of power grid
CN115833221A (en) Method for determining load model considering voltage characteristics of photovoltaic grid-connected point of power distribution network
CN117147942A (en) Short-circuit current calculation method for new energy power station access power system
CN117498548A (en) Rotational inertia online monitoring method and system for new energy-containing power system

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
TA01 Transfer of patent application right

Effective date of registration: 20220624

Address after: 100192 Beijing city Haidian District Qinghe small Camp Road No. 15

Applicant after: CHINA ELECTRIC POWER RESEARCH INSTITUTE Co.,Ltd.

Applicant after: STATE GRID JIBEI ELECTRIC POWER Co.,Ltd.

Address before: 100192 Beijing city Haidian District Qinghe small Camp Road No. 15

Applicant before: CHINA ELECTRIC POWER RESEARCH INSTITUTE Co.,Ltd.

TA01 Transfer of patent application right
GR01 Patent grant
GR01 Patent grant