CN113471972A - Method and system for monitoring inertia of power system - Google Patents

Method and system for monitoring inertia of power system Download PDF

Info

Publication number
CN113471972A
CN113471972A CN202111029515.0A CN202111029515A CN113471972A CN 113471972 A CN113471972 A CN 113471972A CN 202111029515 A CN202111029515 A CN 202111029515A CN 113471972 A CN113471972 A CN 113471972A
Authority
CN
China
Prior art keywords
inertia
power system
generator set
power
node
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.)
Granted
Application number
CN202111029515.0A
Other languages
Chinese (zh)
Other versions
CN113471972B (en
Inventor
王铁柱
马士聪
郭剑波
荆逸然
侯玮琳
徐浩田
罗魁
范士雄
赵兵
王姗姗
汪梦军
王国政
周子涵
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
Original Assignee
China Electric Power Research Institute Co Ltd CEPRI
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 filed Critical China Electric Power Research Institute Co Ltd CEPRI
Priority to CN202111029515.0A priority Critical patent/CN113471972B/en
Publication of CN113471972A publication Critical patent/CN113471972A/en
Application granted granted Critical
Publication of CN113471972B publication Critical patent/CN113471972B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

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
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/08—Locating faults in cables, transmission lines, or networks
    • G01R31/088—Aspects of digital computing
    • 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
    • H02J3/24—Arrangements for preventing or reducing oscillations of power in networks
    • H02J3/241—The oscillation concerning frequency
    • 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
    • H02J2203/10—Power transmission or distribution systems management focussing at grid-level, e.g. load flow analysis, node profile computation, meshed network optimisation, active network management or spinning reserve management
    • 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]

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Mathematical Physics (AREA)
  • Theoretical Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Supply And Distribution Of Alternating Current (AREA)

Abstract

The invention provides a method and a system for monitoring inertia of a power system, which are characterized in that the equivalent rotational inertia of a system considering frequency distribution characteristics and new energy power generation inertia supporting capacity is obtained through the calculation of acquired synchronous generator set information, new energy generator set information and network information of the power system, and the rotational inertia monitoring result of the power system is determined through the comparison with the system equivalent rotational inertia threshold value obtained through calculation by combining the actual condition of a power grid and a topological structure. The system equivalent rotary inertia determined by the method and the system can reflect the actual operation condition of the system more accurately, and the rotary inertia prediction result of the system is more accurate by comparing with a more refined power grid equivalent rotary inertia threshold value obtained by combining the actual condition of the power grid and the network topological structure.

Description

Method and system for monitoring inertia of power system
Technical Field
The present invention relates to the field of power system operation control, and more particularly, to a method and system for monitoring inertia for a power system.
Background
The energy crisis makes more and more attention paid to the research and utilization of new energy, and new energy power generation is a main way to utilize new energy. With the gradual increase of the new energy power generation proportion, the large-scale new energy power generation replaces the traditional synchronous generator set to generate power, so that the rotational inertia of the system is reduced, the transient supporting capacity of the system to the frequency is weakened, and the frequency out-of-limit risk is increased. In addition, as the number and capacity of extra-high voltage direct-current transmission projects increase year by year, the frequency stability level of the system mainly depends on the equivalent moment of inertia of the system: the larger the equivalent moment of inertia, the higher the system frequency stability level.
In order to improve the safe and stable operation level of the system and perform risk early warning and operation guidance on the system, it is necessary to monitor the equivalent rotational inertia of the system. With the replacement of the power generation of the traditional synchronous generator set by the new energy power generation and the adoption of virtual synchronous control or virtual inertia control by the new energy generator set to provide inertia support for the system, the uneven distribution of the rotational inertia in the system is intensified. Due to the reasons, the frequency distribution characteristic of the system after disturbance is more and more obvious, and the new energy power generation inertia supporting capacity is difficult to quantify. Under the background, the traditional inertia monitoring system for simply adding the rotational inertia of the synchronous machine has extremely large error and cannot meet the system operation requirement, and at present, no power system inertia monitoring system considering the frequency distribution characteristic of a power system comprising a new energy generating set and the new energy generating inertia supporting capacity exists at home and abroad.
Disclosure of Invention
In order to solve the problem that the proportion of new energy generator sets in a power system is increasing day by day, but the inertia monitoring technology of the power system considering the frequency distribution characteristic of the power system comprising the new energy generator sets and the supporting capability of the new energy generation inertia is not considered, the invention provides a method for monitoring the inertia of the power system, which comprises the following steps:
acquiring synchronous generator set information and new energy generator set information of an electric power system and network information of the electric power system, wherein the synchronous generator set information comprises rotational inertia of a synchronous engine set;
calculating a disturbance power distribution coefficient of the synchronous generator set by combining the synchronous generator set information and network information based on the disturbance power of a node j of the power system, wherein the disturbance power of the node j is given by fault set information;
calculating the equivalent inertia of the new energy generator set by combining the rotational inertia of the synchronous generator set and the information of the new energy generator set based on the disturbance power of the node j of the power system;
calculating the system equivalent rotational inertia of the power system according to the disturbance power distribution coefficient and the rotational inertia of the synchronous generator set and the equivalent inertia of the new energy generator set;
calculating a system equivalent rotational inertia threshold value of the power system according to the maximum frequency deviation allowed by the power system and a rated angular speed based on the disturbance power of a node j of the power system, and determining a rotational inertia monitoring result of the power system according to the system equivalent rotational inertia and the equivalent rotational inertia threshold value, wherein the rotational inertia monitoring result comprises normal rotational inertia and abnormal rotational inertia.
Further, calculating a disturbance power distribution coefficient of the synchronous generator set by combining the synchronous generator set information and the network information based on the disturbance power of the node j of the power system comprises:
according to the sub-transient reactance of the synchronous generator setx’ dgGenerating generator admittance matrix YgenThe expression is;
according to the terminal voltage U of each synchronous generator set g Generator terminal voltage vector Ugen；
According to generator admittance matrix YgenGenerating a generator-node association admittance matrix Y with the generator-node network association matrix Agn；
According to the node admittance matrix YnetAnd generator admittance matrix YgenGenerating a modified node admittance matrix Ynet ’The expression is as follows:
Figure 497204DEST_PATH_IMAGE001
according to node voltage UnActive power P of nodenAnd node reactive power QnGenerating a load admittance matrix YLPQThe expression is as follows:
Figure 856422DEST_PATH_IMAGE002
disturbance power delta P based on node j of power systemjAnd injected perturbation power Δ PjNode j ofjCalculating a disturbance current vector Δ I of the power systemj_nThe expression is as follows:
Figure 573842DEST_PATH_IMAGE003
according to the terminal voltage vector UgenGenerator-node association admittance matrix YgnCorrecting the nodal admittance matrix Ynet ’Load admittance matrix YLPQThe disturbance current vector Δ Ij_nAnd disturbance power Δ PjCalculating disturbance power distribution coefficient K of synchronous generator setj_PDFThe calculation formula is as follows:
Figure 641155DEST_PATH_IMAGE004
wherein the synchronous generator set information includes a collected synchronous generator set sub-transient reactancex’ dgAnd terminal voltage U of synchronous generator setgG is the number of the generator, G is more than or equal to 1 and less than or equal to G, and G is the total number of the synchronous generator sets in the power system; the network information comprises a generator-node network incidence matrix A and a node admittance matrix Y which are collectednetNode voltage UnActive power P of nodenNode reactive power QnN is the node number, N is more than or equal to 1 and less than or equal to N, and N is the total number of the nodes in the power system.
Further, calculating the equivalent inertia of the new energy generator set by combining the rotational inertia of the synchronous generator set and the new energy generator set information based on the disturbance power of the node j of the power system comprises:
calculating the equivalent inertia J of the new energy generator set controlled by the virtual synchronizerv_eqThe formula of (1) is:
calculating the equivalent inertia J of the new energy generator set controlled by the virtual inertiaw_eqThe formula of (1) is:
Figure 393211DEST_PATH_IMAGE005
in the formula, the new energy is used as energyThe motor group information comprises a virtual inertia parameter J of the new energy generator group controlled by the virtual synchronizer in an acquired modevV is the number of the new energy generator set controlled by the virtual synchronizer, V is more than or equal to 1 and less than or equal to V, V is the total number of the new energy generator set controlled by the virtual synchronizer in the power system, and the rated capacity S of the new energy generator set controlled by the virtual inertia is further includedwCoefficient of inertia support power kwInertia support input delay time tdwW is the number of the new energy generator set controlled by the virtual inertia, W is more than or equal to 1 and less than or equal to W, W is the total number of the new energy generator sets controlled by the virtual inertia in the power system, and delta PjGiving disturbance power to a node j of the power system in the fault set information, wherein j is more than or equal to 1 and less than or equal to N, N is the total number of nodes in the power system, tcFor a given safety action time, J, in the fault set informationgG is larger than or equal to 1 and smaller than or equal to G, and G is the total number of the synchronous generator sets in the power system.
Further, the calculating the system equivalent rotational inertia of the power system according to the disturbance power distribution coefficient and the rotational inertia of the synchronous generator set and the system equivalent rotational inertia of the new energy generator set comprises:
calculating the minimum equivalent moment of inertia J of the power system according to the disturbance power distribution coefficient and the moment of inertia of the synchronous generator setj_eq_minThe calculation formula is as follows:
Figure 651892DEST_PATH_IMAGE006
in the formula, JgFor synchronizing the rotary inertia of the generator set, Kj__PDFgDisturbance power distribution coefficient K for synchronous generator setj_PDFG is more than or equal to 1 and less than or equal to G, and G is the total number of synchronous generator sets in the power system;
calculating the area equivalent rotational inertia J of the power system according to the disturbance power distribution coefficient and the rotational inertia of the synchronous generator set and the equivalent inertia of the new energy generator setj_eq_zoneThe calculation formula is as follows:
Figure 591029DEST_PATH_IMAGE007
in the formula, JjGiving a disturbance power Δ P to a node j of the power system in fault set informationjThen, the rotational inertia of the synchronous generator set and the equivalent inertia, K, of the new energy generator set in the region Z defined by the power systemj_PDFgDisturbance power distribution coefficient K for synchronous generator setj_PDFG is a synchronous generator set in a zone Z defined by the power system.
Further, calculating a system equivalent moment of inertia threshold value of the power system according to the maximum frequency deviation allowed by the power system and the rated angular speed based on the disturbance power of the node j of the power system, and determining a moment of inertia monitoring result of the power system according to the system equivalent moment of inertia and the equivalent moment of inertia threshold value comprises:
calculating a system equivalent moment inertia threshold J of the power system according to the maximum frequency deviation and the rated angular speed allowed by the power system based on the disturbance power of the node J of the power systemj_eq_thThe calculation formula is as follows:
Figure 727612DEST_PATH_IMAGE008
in the formula,. DELTA.PjGiven a disturbance power, t, for a node j of the power system in fault set informationcFor a given safety action time, Δ f, in the fault set informationmaxMaximum frequency deviation, ω, allowed for the power system0Is the rated angular speed of the power system;
comparing the equivalent moment of inertia threshold J of the systemj_eq_thAnd the minimum equivalent moment of inertia Jj_eq_minWhen J isj_eq_min＜Jj_eq_thDetermining a rotational inertia of the power systemAbnormal volume, when Jj_eq_min≥Jj_eq_thDetermining that the rotational inertia of the power system is normal;
comparing the equivalent moment of inertia threshold J of the systemj_eq_thAnd area equivalent moment of inertia Jj_eq_zoneWhen J isj_eq_zone＜Jj_eq_thWhen the moment of inertia of the power system is abnormal, when Jj_eq_zone≥Jj_eq_thAnd determining that the rotation of the power system is normal.
According to another aspect of the present invention, there is provided a system for monitoring inertia for a power system, the system comprising:
the system comprises a data acquisition unit, a data processing unit and a control unit, wherein the data acquisition unit is used for acquiring synchronous generator set information and new energy generator set information of an electric power system and network information of the electric power system, and the synchronous generator set information comprises the rotational inertia of a synchronous engine set;
the first calculation unit is used for calculating a disturbance power distribution coefficient of the synchronous generator set by combining the synchronous generator set information and the network information based on the disturbance power of a node j of the power system, wherein the disturbance power of the node j is given by fault set information;
the second calculation unit is used for calculating the equivalent inertia of the new energy generator set by combining the rotational inertia of the synchronous generator set and the information of the new energy generator set based on the disturbance power of the node j of the power system;
the third calculation unit is used for calculating the system equivalent rotational inertia of the power system according to the disturbance power distribution coefficient and the rotational inertia of the synchronous generator set and the system equivalent rotational inertia of the new energy generator set;
and the result analysis unit is used for calculating a system equivalent moment of inertia threshold value of the power system according to the maximum frequency deviation allowed by the power system and the rated angular speed based on the disturbance power of the node j of the power system, and determining a moment of inertia monitoring result of the power system according to the system equivalent moment of inertia and the equivalent moment of inertia threshold value, wherein the moment of inertia monitoring result comprises normal moment of inertia and abnormal moment of inertia.
Further, the calculating, by the first calculating unit, a disturbance power distribution coefficient of the synchronous generator set based on the disturbance power of the node j of the power system by combining the synchronous generator set information and the network information includes:
according to the sub-transient reactance of the synchronous generator setx’ dgGenerating generator admittance matrix Ygen；
According to the terminal voltage U of each synchronous generator set g Generator terminal voltage vector Ugen(ii) a Motor admittance matrix YgenGenerating a generator-node association admittance matrix Y with the generator-node network association matrix Agn；
According to the node admittance matrix YnetAnd generator admittance matrix YgenGenerating a modified node admittance matrix Ynet ’The expression is as follows:
Figure 334174DEST_PATH_IMAGE001
according to node voltage UnActive power P of nodenAnd node reactive power QnGenerating a load admittance matrix YLPQThe expression is as follows:
Figure 124275DEST_PATH_IMAGE002
based on disturbance power DeltaP given to one node j of the power system in fault set informationjAnd injected perturbation power Δ PjNode j ofjCalculating a disturbance current vector Δ I of the power systemj_nThe expression is as follows:
Figure 314823DEST_PATH_IMAGE003
according to the terminal voltage vector UgenGenerator-node association admittance matrix YgnCorrecting the nodal admittance matrix Ynet ’Admittance of a loadMatrix YLPQThe disturbance current vector Δ Ij_nAnd disturbance power Δ PjCalculating disturbance power distribution coefficient K of synchronous generator setj_PDFThe calculation formula is as follows:
Figure 723939DEST_PATH_IMAGE004
wherein the synchronous generator set information comprises acquired sub-transient reactance of the synchronous generator setx’ dgAnd terminal voltage U of synchronous generator setgG is the number of the generator, G is more than or equal to 1 and less than or equal to G, and G is the total number of the synchronous generator sets in the power system; the network information comprises a generator-node network incidence matrix A and a node admittance matrix Y which are collectednetNode voltage UnActive power P of nodenNode reactive power QnN is the node number, N is more than or equal to 1 and less than or equal to N, and N is the total number of the nodes in the power system.
Further, the calculating, by the second calculating unit, the equivalent inertia of the new energy generator set based on the disturbance power of the node j of the power system by combining the rotational inertia of the synchronous generator set and the new energy generator set information includes:
calculating the equivalent inertia J of the new energy generator set controlled by the virtual synchronizerv_eqThe formula of (1) is:
Jv_eq= Jv
calculating the equivalent inertia J of the new energy generator set controlled by the virtual inertiaw_eqThe formula of (1) is:
Figure 185007DEST_PATH_IMAGE005
in the formula, the new energy generator set information comprises a virtual inertia parameter J of the new energy generator set controlled by the virtual synchronizer in an acquisition modevV is the number of the new energy generator set controlled by the virtual synchronizer, V is more than or equal to 1 and less than or equal to V, and V is the new energy controlled by the virtual synchronizer in the power systemThe total number of the source generator sets and the rated capacity S of the new energy generator set controlled by the virtual inertiawCoefficient of inertia support power kwInertia support input delay time tdwW is the number of the new energy generator set controlled by the virtual inertia, W is more than or equal to 1 and less than or equal to W, W is the total number of the new energy generator sets controlled by the virtual inertia in the power system, and delta PjGiving disturbance power to a node j of the power system in the fault set information, wherein j is more than or equal to 1 and less than or equal to N, N is the total number of nodes in the power system, tcFor a given safety action time, J, in the fault set informationgG is larger than or equal to 1 and smaller than or equal to G, and G is the total number of the synchronous generator sets in the power system.
Further, the third calculating unit calculates the system equivalent rotational inertia of the power system according to the disturbance power distribution coefficient and the rotational inertia of the synchronous generator set and the system equivalent rotational inertia of the new energy generator set, and includes:
calculating the minimum equivalent moment of inertia J of the power system according to the disturbance power distribution coefficient and the moment of inertia of the synchronous generator setj_eq_minThe calculation formula is as follows:
Figure 552534DEST_PATH_IMAGE006
in the formula, JgFor synchronizing the rotary inertia of the generator set, Kj__PDFgDisturbance power distribution coefficient K for synchronous generator setj_PDFG is more than or equal to 1 and less than or equal to G, and G is the total number of synchronous generator sets in the power system;
calculating the area equivalent rotational inertia J of the power system according to the disturbance power distribution coefficient and the rotational inertia of the synchronous generator set and the equivalent inertia of the new energy generator setj_eq_zoneThe calculation formula is as follows:
Figure 964799DEST_PATH_IMAGE007
in the formula, JjGiving a disturbance power Δ P to a node j of the power system in fault set informationjThen, the rotational inertia of the synchronous generator set and the equivalent inertia, K, of the new energy generator set in the region Z defined by the power systemj_PDFgDisturbance power distribution coefficient K for synchronous generator setj_PDFG is a synchronous generator set in a zone Z defined by the power system.
Further, the step of calculating, by a result analysis unit, a system equivalent moment of inertia threshold value of the power system according to a maximum frequency deviation allowed by the power system and a rated angular velocity based on disturbance power of a node j of the power system, and determining a moment of inertia monitoring result of the power system according to the system equivalent moment of inertia and the equivalent moment of inertia threshold value includes:
calculating a system equivalent moment inertia threshold J of the power system according to the maximum frequency deviation and the rated angular speed allowed by the power system based on the disturbance power of the node J of the power systemj_eq_thThe calculation formula is as follows:
Figure 912026DEST_PATH_IMAGE008
in the formula,. DELTA.PjGiven a disturbance power, t, for a node j of the power system in fault set informationcFor a given safety action time, Δ f, in the fault set informationmaxMaximum frequency deviation, ω, allowed for the power system0Is the rated angular speed of the power system;
comparing the equivalent moment of inertia threshold J of the systemj_eq_thAnd the minimum equivalent moment of inertia Jj_eq_minWhen J isj_eq_min＜Jj_eq_thWhen the moment of inertia of the power system is abnormal, when Jj_eq_min≥Jj_eq_thDetermining that the rotational inertia of the power system is normal;
comparing the equivalent moment of inertia threshold J of the systemj_eq_thEquivalent rotation inertia of sum regionQuantity Jj_eq_zoneWhen J isj_eq_zone＜Jj_eq_thWhen the moment of inertia of the power system is abnormal, when Jj_eq_zone≥Jj_eq_thAnd determining that the rotation of the power system is normal.
The method and the system for monitoring the inertia of the power system, provided by the technical scheme of the invention, respectively quantize the equivalent inertia of the new energy generator set controlled by adopting the virtual synchronous machine and controlled by adopting the virtual inertia, calculate the disturbance power distribution coefficient of disturbance power injected by different nodes at the nodes of the synchronous generator based on the synchronous generator information and the network topology information in the power system, and calculate the system equivalent rotational inertia aiming at each power disturbance node according to the disturbance power distribution coefficient, thereby obtaining the system equivalent rotational inertia considering the frequency distribution characteristic and the new energy power generation inertia supporting capacity, and determining the rotational inertia monitoring result of the power system by comparing with the system equivalent rotational inertia threshold calculated by combining the actual condition of a power grid and the topological structure. The system equivalent rotary inertia determined by the method and the system can reflect the actual operation condition of the system more accurately, and the rotary inertia prediction result of the system is more accurate by comparing with a more refined power grid equivalent rotary inertia threshold value obtained by combining the actual condition of the power grid and the network topological structure.
Drawings
A more complete understanding of exemplary embodiments of the present invention may be had by reference to the following drawings in which:
FIG. 1 is a flow chart of a method for monitoring inertia for a power system in accordance with a preferred embodiment of the present invention;
FIG. 2 is a schematic diagram of an electrical power system test example 1 according to a preferred embodiment of the present invention;
FIG. 3 is a comparison graph of simulation results of system frequency changes of test example 1 and test example 2 of the power system according to the preferred embodiment of the present invention;
FIG. 4 is a schematic diagram of the node frequency simulation results of test example 1 according to the preferred embodiment of the present invention;
fig. 5 is a schematic structural diagram of a system for monitoring inertia for a power system according to a preferred 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 embodiments described herein, which are provided for complete and complete disclosure of the present invention and to fully convey the scope of the present 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, the same units/elements are denoted by the same reference numerals.
Unless otherwise defined, terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Further, it will be understood that terms, such as those 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 for monitoring inertia for a power system according to a preferred embodiment of the present invention. As shown in fig. 1, a method 100 for monitoring inertia of a power system according to the preferred embodiment begins with step 101.
In step 101, synchronous generator set information and new energy generator set information of an electric power system and network information of the electric power system are collected, wherein the synchronous generator set information comprises rotational inertia of a synchronous engine set.
In step 102, calculating a disturbance power distribution coefficient of the synchronous generator set by combining the synchronous generator set information and the network information based on the disturbance power of a node j of the power system, wherein the disturbance power of the node j is given by fault set information;
in step 103, calculating equivalent inertia of the new energy generator set by combining the rotational inertia of the synchronous generator set and the information of the new energy generator set based on the disturbance power of the node j of the power system;
in step 104, calculating the system equivalent rotational inertia of the power system according to the disturbance power distribution coefficient and the rotational inertia of the synchronous generator set and the equivalent inertia of the new energy generator set;
in step 105, based on disturbance power of a node j of the electric power system, calculating a system equivalent moment of inertia threshold value of the electric power system according to a maximum frequency deviation allowed by the electric power system and a rated angular velocity, and determining a moment of inertia monitoring result of the electric power system according to the system equivalent moment of inertia and the equivalent moment of inertia threshold value, wherein the moment of inertia monitoring result comprises normal moment of inertia and abnormal moment of inertia.
Preferably, calculating the disturbance power distribution coefficient of the synchronous generator set by combining the synchronous generator set information and the network information based on the disturbance power of the node j of the power system comprises:
according to the sub-transient reactance of the synchronous generator setx’ dgGenerating generator admittance matrix YgenThe expression is as follows:
Figure 493180DEST_PATH_IMAGE009
according to the terminal voltage U of each synchronous generator set g Generator terminal voltage vector UgenThe expression is as follows:
Figure 625085DEST_PATH_IMAGE010
according to generator admittance matrix YgenGenerating a generator-node association admittance matrix Y with the generator-node network association matrix AgnThe calculation formula is as follows:
Figure 291689DEST_PATH_IMAGE011
according to the node admittance matrix YnetAnd generator admittance matrix YgenGenerating a modified node admittance matrix Ynet ’The expression is as follows:
Figure 800863DEST_PATH_IMAGE001
according to node voltage UnActive power P of nodenAnd node reactive power QnGenerating a load admittance matrix YLPQThe expression is as follows:
Figure 970944DEST_PATH_IMAGE002
based on disturbance power DeltaP given to one node j of the power system in fault set informationjAnd injected perturbation power Δ PjNode j ofjCalculating a disturbance current vector Δ I of the power systemj_nThe expression is as follows:
Figure 680274DEST_PATH_IMAGE003
according to the terminal voltage vector UgenGenerator-node association admittance matrix YgnCorrecting the nodal admittance matrix Ynet ’Load admittance matrix YLPQThe disturbance current vector Δ Ij_nAnd disturbance power Δ PjCalculating disturbance power distribution coefficient K of synchronous generator setj_PDFThe calculation formula is as follows:
Figure 303016DEST_PATH_IMAGE004
wherein the synchronous generator set information includes a collected synchronous generator set sub-transient reactancex’ dgAnd terminal voltage U of synchronous generator setgG is the number of the generator, G is more than or equal to 1 and less than or equal to G, and G is the total number of the synchronous generator sets in the power system; the network information packetGenerator-node network incidence matrix A and node admittance matrix Y including collectionnetNode voltage UnActive power P of nodenNode reactive power QnN is the node number, N is more than or equal to 1 and less than or equal to N, and N is the total number of the nodes in the power system.
Preferably, calculating the equivalent inertia of the new energy generator set by combining the rotational inertia of the synchronous generator set and the new energy generator set information based on the disturbance power of the node j of the power system comprises:
calculating the equivalent inertia J of the new energy generator set controlled by the virtual synchronizerv_eqThe formula of (1) is:
Jv_eq= Jv
calculating the equivalent inertia J of the new energy generator set controlled by the virtual inertiaw_eqThe formula of (1) is:
Figure 356161DEST_PATH_IMAGE005
in the formula, the new energy generator set information comprises a virtual inertia parameter J of the new energy generator set controlled by the virtual synchronizer in an acquisition modevV is the number of the new energy generator set controlled by the virtual synchronizer, V is more than or equal to 1 and less than or equal to V, V is the total number of the new energy generator set controlled by the virtual synchronizer in the power system, and the rated capacity S of the new energy generator set controlled by the virtual inertia is further includedwCoefficient of inertia support power kwInertia support input delay time tdwW is the number of the new energy generator set controlled by the virtual inertia, W is more than or equal to 1 and less than or equal to W, W is the total number of the new energy generator sets controlled by the virtual inertia in the power system, and delta PjGiving disturbance power to a node j of the power system in the fault set information, wherein j is more than or equal to 1 and less than or equal to N, N is the total number of nodes in the power system, tcFor a given safety action time, J, in the fault set informationgG is more than or equal to 1 and less than or equal to G which is the total number of the synchronous generator sets in the power systemAmount of the compound (A).
In practical application, a node set for disturbance injection is given in fault set information, so that when a disturbance power distribution coefficient of a synchronous generator set is calculated, the disturbance power distribution coefficient of the synchronous generator set and an equivalent inertia of a new energy generator set controlled by virtual inertia are calculated for each node for injecting disturbance in the node set, and on the basis, an equivalent moment of inertia of a power system is calculated, so that early warning of a system moment of inertia state is also performed for influences of disturbance power injected by each node in the node set for disturbance injection on other nodes in the power system.
Preferably, the calculating the system equivalent rotational inertia of the power system according to the disturbance power distribution coefficient and the rotational inertia of the synchronous generator set and the system equivalent rotational inertia of the new energy generator set comprises:
calculating the minimum equivalent moment of inertia J of the power system according to the disturbance power distribution coefficient and the moment of inertia of the synchronous generator setj_eq_minThe calculation formula is as follows:
Figure 505382DEST_PATH_IMAGE006
in the formula, JgFor synchronizing the rotary inertia of the generator set, Kj_PDFgDisturbance power distribution coefficient K for synchronous generator setj_PDFG is not less than 1 and not more than G, and G is the total number of synchronous generator sets in the power system.
Calculating the area equivalent rotational inertia J of the power system according to the disturbance power distribution coefficient and the rotational inertia of the synchronous generator set and the equivalent inertia of the new energy generator setj_eq_zoneThe calculation formula is as follows:
Figure 120034DEST_PATH_IMAGE007
in the formula, JjGiving a node j of the power system in fault set informationDisturbance power Δ PjThen, the rotational inertia of the synchronous generator set and the equivalent inertia, K, of the new energy generator set in the region Z defined by the power systemj_PDFgDisturbance power distribution coefficient K for synchronous generator setj_PDFG is a synchronous generator set in a zone Z defined by the power system.
Preferably, calculating a system equivalent inertia moment threshold value of the power system according to a maximum frequency deviation allowed by the power system and a rated angular velocity based on disturbance power of a node j of the power system, and determining a moment inertia monitoring result of the power system according to the system equivalent inertia moment and the equivalent inertia moment threshold value comprises:
calculating a system equivalent moment inertia threshold J of the power system according to the maximum frequency deviation and the rated angular speed allowed by the power system based on the disturbance power of the node J of the power systemj_eq_thThe calculation formula is as follows:
Figure 230073DEST_PATH_IMAGE008
in the formula,. DELTA.PjGiven a disturbance power, t, for a node j of the power system in fault set informationcFor a given safety action time, Δ f, in the fault set informationmaxMaximum frequency deviation, ω, allowed for the power system0Is the rated angular speed of the power system;
comparing the equivalent moment of inertia threshold J of the systemj_eq_thAnd the minimum equivalent moment of inertia Jj_eq_minWhen J isj_eq_min＜Jj_eq_thWhen the moment of inertia of the power system is abnormal, when Jj_eq_min≥Jj_eq_thDetermining that the rotational inertia of the power system is normal;
comparing the equivalent moment of inertia threshold J of the systemj_eq_thAnd area equivalent moment of inertia Jj_eq_zoneWhen J isj_eq_zone＜Jj_eq_thDetermining a difference in rotational inertia of the power systemWhen J is frequentj_eq_zone≥Jj_eq_thAnd determining that the rotation of the power system is normal.
In order to verify the effectiveness of the method for monitoring the inertia of the power system, the preferred embodiment verifies the method based on the test example 1 modified by the IEEE9 node example. FIG. 2 is a schematic diagram of an exemplary test algorithm for an electrical power system according to a preferred embodiment of the present invention. As shown in FIG. 2, a wind generating set adopting virtual inertia control is added at bus-6, bus-1 and bus-3 are synchronous generating sets, and the other 3 nodes are non-engine nodes. The key parameters of bus-1, bus-3 and bus-6 are shown in table 1, the line parameters are shown in table 2, and the load parameters are shown in table 3.
Table 1 key parameters of the unit in example 1
Figure 322794DEST_PATH_IMAGE012
TABLE 2 Circuit parameters in EXAMPLE 1
Front side node Rear side node Line resistor (pu) Line reactance (pu)
bus-1 bus-4 0 0.0576
bus-4 bus-6 0.017 0.092
bus-6 bus-9 0.039 0.17
bus-3 bus-9 0 0.0586
bus-9 bus-8 0.0119 0.01008
TABLE 3 load parameters in EXAMPLE 1
Node point Active load (MW) Reactive load (Mvar)
bus-6 90 30
bus-8 100 35
In test example 1, a power disturbance fault occurred at set 0.1s, and the load dropped 40MW, i.e., Δ P, at bus-8j=40MW, safety control action time tc=0.3S。
Substituting the parameters into a new energy generator set adopting virtual inertia control to calculate the equivalent inertia J of the new energy generator setw_eqThe calculated equivalent inertia of the wind generating set providing the inertia support is as follows:
Figure 592101DEST_PATH_IMAGE013
in order to verify the correctness of the result, a comparative verification group test example 2 is arranged, the wind generating set at bus-6 in the simulation example is replaced by a synchronous generator with the capacity of 200MW and the inertia Jg =4 t.m 2, and whether the calculation method is correct is proved through the consistency of the frequencies of the example 1 and the example 2 at the safety control action moment (the delay tc time after the fault).
Fig. 3 is a comparison graph of simulation results of system frequency changes of the power system test example 1 and the test example 2 according to the preferred embodiment of the present invention. As shown in fig. 3, at 0.4s of the safety control action time, the frequencies of the test example 1 and the test example 2 are the same, which effectively proves the effectiveness of the equivalent inertia calculation method provided by the invention when a new energy generator set exists in the power system.
Further, according to the line parameters in Table 2 and the load parameters in Table 3, K of bus-1 and bus-3 at the bus-8 position when power disturbance occurs can be calculatedPDF0.18 and 0.82, respectively. Then according to a formula for calculating the minimum equivalent moment of inertia of the power system:
Figure 141769DEST_PATH_IMAGE014
classifying all the nodes in the test calculation example 1 into the same region, and then according to a calculation formula of the region equivalent moment of inertia:
Figure 739103DEST_PATH_IMAGE015
let the maximum frequency deviation Δ fmax =0.5Hz allowed by the system, then the formula is calculated according to the equivalent moment of inertia threshold:
Figure DEST_PATH_IMAGE016
therefore, according to the method of the rotation monitoring result of the power system, the equivalent moment of inertia of the system area is equal to the equivalent moment of inertia threshold value, namely the integral frequency of the area as the same inertia center is not out of limit at the moment, and fig. 3 just proves the conclusion, and the system frequency is just close to the critical position of 50.5Hz at the moment. And the minimum equivalent moment of inertia index considering the frequency distribution characteristics is smaller than the equivalent moment of inertia threshold value, which shows that a frequency out-of-limit node exists.
FIG. 4 is a diagram illustrating the simulation results of node frequency of test example 1 according to the preferred embodiment of the present invention. As shown in fig. 4, for the bus1 and bus3 installed with synchronous generators, the frequency was below 50.4Hz for bus1, while the frequency exceeded 50.5Hz after 0.2s for bus3, which was clearly out of limit, and the calculated results were consistent with the test results.
Fig. 2 is a schematic structural diagram of a system for monitoring inertia for a power system according to a preferred embodiment of the present invention. As shown in fig. 2, the system 200 for monitoring inertia of a power system according to the preferred embodiment includes:
the data acquisition unit 201 is configured to acquire synchronous generator set information and new energy generator set information of the power system, and network information of the power system, where the synchronous generator set information includes rotational inertia of a synchronous engine set.
A first calculating unit 202, configured to calculate a disturbance power distribution coefficient of the synchronous generator set by combining the synchronous generator set information and the network information based on disturbance power of a node j of the power system, where the disturbance power of the node j is given by fault set information.
And a second calculating unit 203, configured to calculate, based on the disturbance power of the node j of the power system, an equivalent inertia of the new energy generator set by combining the rotational inertia of the synchronous generator set and the information of the new energy generator set.
And the third calculating unit 204 is configured to calculate a system equivalent rotational inertia of the power system according to the disturbance power distribution coefficient and the rotational inertia of the synchronous generator set and the system equivalent rotational inertia of the new energy generator set.
A result analyzing unit 205, configured to calculate a system equivalent rotational inertia threshold value of the power system according to a maximum frequency deviation allowed by the power system and a rated angular velocity based on a disturbance power of a node j of the power system, and determine a rotational inertia monitoring result of the power system according to the system equivalent rotational inertia and the equivalent rotational inertia threshold value, where the rotational inertia monitoring result includes a normal rotational inertia and an abnormal rotational inertia.
Preferably, the calculating, by the first calculating unit 202, based on the disturbance power of the node j of the power system, the disturbance power distribution coefficient of the synchronous generator set by combining the synchronous generator set information and the network information includes:
according to the sub-transient reactance of the synchronous generator setx’ dgGenerating generator admittance matrix YgenThe expression is as follows:
Figure 307619DEST_PATH_IMAGE009
according to the terminal voltage U of each synchronous generator set g Generator terminal voltage vector UgenThe expression is as follows:
Figure 165854DEST_PATH_IMAGE010
according to generator admittance matrix YgenGenerating generator with generator-node network incidence matrix A-a node-associated admittance matrix YgnThe calculation formula is as follows:
Figure 620844DEST_PATH_IMAGE011
according to the node admittance matrix YnetAnd generator admittance matrix YgenGenerating a modified node admittance matrix Ynet ’The expression is as follows:
Figure 705474DEST_PATH_IMAGE001
according to node voltage UnActive power P of nodenAnd node reactive power QnGenerating a load admittance matrix YLPQThe expression is as follows:
Figure 405577DEST_PATH_IMAGE002
based on disturbance power DeltaP given to one node j of the power system in fault set informationjAnd injected perturbation power Δ PjNode j ofjCalculating a disturbance current vector Δ I of the power systemj_nThe expression is as follows:
Figure 524843DEST_PATH_IMAGE003
according to the terminal voltage vector UgenGenerator-node association admittance matrix YgnCorrecting the nodal admittance matrix Ynet ’Load admittance matrix YLPQThe disturbance current vector Δ Ij_nAnd disturbance power Δ PjCalculating disturbance power distribution coefficient K of synchronous generator setj_PDFThe calculation formula is as follows:
Figure 511253DEST_PATH_IMAGE004
wherein the synchronous power generationSynchronous generator set sub-transient reactance with unit information including acquisitionx’ dgAnd terminal voltage U of synchronous generator setgG is the number of the generator, G is more than or equal to 1 and less than or equal to G, and G is the total number of the synchronous generator sets in the power system; the network information comprises a generator-node network incidence matrix A and a node admittance matrix Y which are collectednetNode voltage UnActive power P of nodenNode reactive power QnN is the node number, N is more than or equal to 1 and less than or equal to N, and N is the total number of the nodes in the power system.
Preferably, the calculating, by the second calculating unit 203, the equivalent inertia of the new energy generator set based on the disturbance power of the node j of the power system and the rotational inertia of the synchronous generator set and the new energy generator set information includes:
calculating the equivalent inertia J of the new energy generator set controlled by the virtual synchronizerv_eqThe formula of (1) is:
Jv_eq= Jv
calculating the equivalent inertia J of the new energy generator set controlled by the virtual inertiaw_eqThe formula of (1) is:
Figure 853154DEST_PATH_IMAGE005
in the formula, the new energy generator set information comprises a virtual inertia parameter J of the new energy generator set controlled by the virtual synchronizer in an acquisition modevV is the number of the new energy generator set controlled by the virtual synchronizer, V is more than or equal to 1 and less than or equal to V, V is the total number of the new energy generator set controlled by the virtual synchronizer in the power system, and the rated capacity S of the new energy generator set controlled by the virtual inertia is further includedwCoefficient of inertia support power kwInertia support input delay time tdwW is the number of the new energy generator set controlled by the virtual inertia, W is more than or equal to 1 and less than or equal to W, W is the total number of the new energy generator sets controlled by the virtual inertia in the power system, and delta PjFor one of fault set information to the power systemGiven disturbance power of each node j, j is more than or equal to 1 and less than or equal to N, N is the total number of nodes in the power system, tcFor a given safety action time, J, in the fault set informationgG is larger than or equal to 1 and smaller than or equal to G, and G is the total number of the synchronous generator sets in the power system.
Preferably, the third calculating unit 204 calculates the system equivalent rotational inertia of the power system according to the disturbance power distribution coefficient and the rotational inertia of the synchronous generator set and the new energy generator set equivalent inertia includes:
calculating the minimum equivalent moment of inertia J of the power system according to the disturbance power distribution coefficient and the moment of inertia of the synchronous generator setj_eq_minThe calculation formula is as follows:
Figure 91368DEST_PATH_IMAGE006
in the formula, JgFor synchronizing the rotary inertia of the generator set, Kj__PDFgDisturbance power distribution coefficient K for synchronous generator setj_PDFG is not less than 1 and not more than G, and G is the total number of synchronous generator sets in the power system.
Calculating the area equivalent rotational inertia J of the power system according to the disturbance power distribution coefficient and the rotational inertia of the synchronous generator set and the equivalent inertia of the new energy generator setj_eq_zoneThe calculation formula is as follows:
Figure 65140DEST_PATH_IMAGE007
in the formula, JjGiving a disturbance power Δ P to a node j of the power system in fault set informationjThen, the rotational inertia of the synchronous generator set and the equivalent inertia, K, of the new energy generator set in the region Z defined by the power systemj_PDFgDisturbance power distribution coefficient K for synchronous generator setj_PDFG is a synchronous generator set in a zone Z defined by the power system.
Preferably, the result analyzing unit 205 calculates a system equivalent inertia moment threshold value of the power system according to the maximum frequency deviation allowed by the power system and the rated angular velocity based on the disturbance power of the node j of the power system, and determines the inertia moment monitoring result of the power system according to the system equivalent inertia moment and the equivalent inertia moment threshold value, including:
calculating a system equivalent moment inertia threshold J of the power system according to the maximum frequency deviation and the rated angular speed allowed by the power system based on the disturbance power of the node J of the power systemj_eq_thThe calculation formula is as follows:
Figure 97818DEST_PATH_IMAGE008
in the formula,. DELTA.PjGiven a disturbance power, t, for a node j of the power system in fault set informationcFor a given safety action time, Δ f, in the fault set informationmaxMaximum frequency deviation, ω, allowed for the power system0Is the rated angular speed of the power system;
comparing the equivalent moment of inertia threshold J of the systemj_eq_thAnd the minimum equivalent moment of inertia Jj_eq_minWhen J isj_eq_min＜Jj_eq_thWhen the moment of inertia of the power system is abnormal, when Jj_eq_min≥Jj_eq_thDetermining that the rotational inertia of the power system is normal;
comparing the equivalent moment of inertia threshold J of the systemj_eq_thAnd area equivalent moment of inertia Jj_eq_zoneWhen J isj_eq_zone＜Jj_eq_thWhen the moment of inertia of the power system is abnormal, when Jj_eq_zone≥Jj_eq_thAnd determining that the rotation of the power system is normal.
The steps of monitoring the rotational inertia of the power system with the high-proportion new energy generator set and early warning by the inertia monitoring system for the power system are the same as the steps adopted by the inertia monitoring method for the power system, the achieved technical effects are the same, and the details are not repeated.
The invention has been described with reference to a few embodiments. However, other embodiments of the invention than the one disclosed above are equally possible within the scope of the invention, as would be apparent to a person skilled in the art from the appended patent claims.
Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to "a/an/the [ device, component, etc ]" are to be interpreted openly as referring to at least one instance of said device, component, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated.
As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams 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.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting the same, and although the present invention is described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications and equivalents may be made to the embodiments of the invention without departing from the spirit and scope of the invention, which is to be covered by the claims.

Claims (12)

1. A method of monitoring inertia for a power system, the method comprising:
acquiring synchronous generator set information and new energy generator set information of an electric power system and network information of the electric power system, wherein the synchronous generator set information comprises rotational inertia of a synchronous engine set;
calculating a disturbance power distribution coefficient of the synchronous generator set by combining the synchronous generator set information and network information based on the disturbance power of a node j of the power system, wherein the disturbance power of the node j is given by fault set information;
calculating the equivalent inertia of the new energy generator set by combining the rotational inertia of the synchronous generator set and the information of the new energy generator set based on the disturbance power of the node j of the power system;
calculating the system equivalent rotational inertia of the power system according to the disturbance power distribution coefficient and the rotational inertia of the synchronous generator set and the equivalent inertia of the new energy generator set;
calculating a system equivalent rotational inertia threshold value of the power system according to the maximum frequency deviation allowed by the power system and a rated angular speed based on the disturbance power of a node j of the power system, and determining a rotational inertia monitoring result of the power system according to the system equivalent rotational inertia and the equivalent rotational inertia threshold value, wherein the rotational inertia monitoring result comprises normal rotational inertia and abnormal rotational inertia.
2. The method of claim 1, wherein the synchronous generator set information comprises collected synchronous generator set sub-transient reactancesx’ dgAnd terminal voltage U of synchronous generator setg(ii) a The network information comprises a generator-node network incidence matrix A and a node admittance matrix Y which are collectednetNode voltage UnActive power P of nodenAnd node reactive power QnCalculating a disturbance power distribution coefficient of the synchronous generator set by combining the synchronous generator set information and the network information based on the disturbance power of the node j of the power system, wherein the calculation comprises the following steps:
according to the sub-transient reactance of the synchronous generator setx’ dgGenerating generator admittance matrix Ygen；
According to the terminal voltage U of each synchronous generator set g Generator terminal voltage vector Ugen；
According to generator admittance matrix YgenGenerating a generator-node association admittance matrix Y with the generator-node network association matrix Agn；
According to the node admittance matrix YnetAnd generator admittanceMatrix YgenGenerating a modified node admittance matrix Ynet ’The expression is as follows:
Figure 425800DEST_PATH_IMAGE001
according to node voltage UnActive power P of nodenAnd node reactive power QnGenerating a load admittance matrix YLPQThe expression is as follows:
Figure 385666DEST_PATH_IMAGE002
based on disturbance power DeltaP given to one node j of the power system in fault set informationjAnd injected perturbation power Δ PjNode j ofjCalculating a disturbance current vector Δ I of the power systemj_nThe expression is as follows:
Figure 302806DEST_PATH_IMAGE003
according to the terminal voltage vector UgenGenerator-node association admittance matrix YgnCorrecting the nodal admittance matrix Ynet ’Load admittance matrix YLPQThe disturbance current vector Δ Ij_nAnd disturbance power Δ PjCalculating disturbance power distribution coefficient K of synchronous generator setj_PDFThe calculation formula is as follows:
Figure 348123DEST_PATH_IMAGE004
in the formula, G is the number of the generator, G is more than or equal to 1 and less than or equal to G, and G is the total number of synchronous generator sets in the power system; n is a node number, N is more than or equal to 1 and less than or equal to N, and N is the total number of nodes in the power system.
3. The method of claim 1, wherein calculating the new energy genset equivalent inertia based on disturbance power of a node j of the power system in combination with the rotational inertia of the synchronous genset and the new energy genset information comprises:
calculating the equivalent inertia J of the new energy generator set controlled by the virtual synchronizerv_eqThe formula of (1) is:
Jv_eq= Jv
calculating the equivalent inertia J of the new energy generator set controlled by the virtual inertiaw_eqThe formula of (1) is:
Figure 8911DEST_PATH_IMAGE005
in the formula, the new energy generator set information comprises a virtual inertia parameter J of the new energy generator set controlled by the virtual synchronizer in an acquisition modevV is the number of the new energy generator set controlled by the virtual synchronizer, V is more than or equal to 1 and less than or equal to V, V is the total number of the new energy generator set controlled by the virtual synchronizer in the power system, and the rated capacity S of the new energy generator set controlled by the virtual inertia is further includedwCoefficient of inertia support power kwInertia support input delay time tdwW is the number of the new energy generator set controlled by the virtual inertia, W is more than or equal to 1 and less than or equal to W, W is the total number of the new energy generator sets controlled by the virtual inertia in the power system, and delta PjGiving disturbance power to a node j of the power system in the fault set information, wherein j is more than or equal to 1 and less than or equal to N, N is the total number of nodes in the power system, tcFor a given safety action time, J, in the fault set informationgG is larger than or equal to 1 and smaller than or equal to G, and G is the total number of the synchronous generator sets in the power system.
4. The method of claim 2, wherein calculating the system equivalent moment of inertia of the power system according to the disturbance power distribution coefficient and the moment of inertia of the synchronous generator set and the new energy generator set equivalent inertia comprises:
calculating the minimum equivalent moment of inertia J of the power system according to the disturbance power distribution coefficient and the moment of inertia of the synchronous generator setj_eq_minThe calculation formula is as follows:
Figure 823284DEST_PATH_IMAGE006
in the formula, JgFor synchronizing the rotary inertia of the generator set, Kj_PDFgDisturbance power distribution coefficient K for synchronous generator setj_PDFG is more than or equal to 1 and less than or equal to G, and G is the total number of synchronous generator sets in the power system;
calculating the area equivalent rotational inertia J of the power system according to the disturbance power distribution coefficient and the rotational inertia of the synchronous generator set and the equivalent inertia of the new energy generator setj_eq_zoneThe calculation formula is as follows:
Figure 176905DEST_PATH_IMAGE007
in the formula, JjGiving a disturbance power Δ P to a node j of the power system in fault set informationjThen, the rotational inertia of the synchronous generator set and the equivalent inertia, K, of the new energy generator set in the region Z defined by the power systemj_PDFgDisturbance power distribution coefficient K for synchronous generator setj_PDFG is a synchronous generator set in a zone Z defined by the power system.
5. The method of claim 4, wherein calculating a system equivalent moment of inertia threshold value of the power system according to a maximum frequency deviation allowed by the power system and a rated angular velocity based on disturbance power of a node j of the power system, and determining a moment of inertia monitoring result of the power system according to the system equivalent moment of inertia and the equivalent moment of inertia threshold value comprises:
calculating a system equivalent moment inertia threshold J of the power system according to the maximum frequency deviation and the rated angular speed allowed by the power system based on the disturbance power of the node J of the power systemj_eq_thThe calculation formula is as follows:
Figure 443938DEST_PATH_IMAGE008
in the formula,. DELTA.PjGiven a disturbance power, t, for a node j of the power system in fault set informationcFor a given safety action time, Δ f, in the fault set informationmaxMaximum frequency deviation, ω, allowed for the power system0Is the rated angular speed of the power system;
comparing the equivalent moment of inertia threshold J of the systemj_eq_thAnd the minimum equivalent moment of inertia Jj_eq_minWhen J isj_eq_min＜Jj_eq_thWhen the moment of inertia of the power system is abnormal, when Jj_eq_min≥Jj_eq_thDetermining that the rotational inertia of the power system is normal;
comparing the equivalent moment of inertia threshold J of the systemj_eq_thAnd area equivalent moment of inertia Jj_eq_zoneWhen J isj_eq_zone＜Jj_eq_thWhen the moment of inertia of the power system is abnormal, when Jj_eq_zone≥Jj_eq_thAnd determining that the rotation of the power system is normal.
6. A system for monitoring inertia for a power system, the system comprising:
the system comprises a data acquisition unit, a data processing unit and a control unit, wherein the data acquisition unit is used for acquiring synchronous generator set information and new energy generator set information of an electric power system and network information of the electric power system, and the synchronous generator set information comprises the rotational inertia of a synchronous engine set;
the first calculation unit is used for calculating a disturbance power distribution coefficient of the synchronous generator set by combining the synchronous generator set information and the network information based on the disturbance power of a node j of the power system, wherein the disturbance power of the node j is given by fault set information;
the second calculation unit is used for calculating the equivalent inertia of the new energy generator set by combining the rotational inertia of the synchronous generator set and the information of the new energy generator set based on the disturbance power of the node j of the power system;
the third calculation unit is used for calculating the system equivalent rotational inertia of the power system according to the disturbance power distribution coefficient and the rotational inertia of the synchronous generator set and the system equivalent rotational inertia of the new energy generator set;
and the result analysis unit is used for calculating a system equivalent moment of inertia threshold value of the power system according to the maximum frequency deviation allowed by the power system and the rated angular speed based on the disturbance power of the node j of the power system, and determining a moment of inertia monitoring result of the power system according to the system equivalent moment of inertia and the equivalent moment of inertia threshold value, wherein the moment of inertia monitoring result comprises normal moment of inertia and abnormal moment of inertia.
7. The system of claim 6, the synchronous generator set information collected by the data acquisition unit comprising a synchronous generator set sub-transient reactancex’ dgAnd terminal voltage U of synchronous generator setg(ii) a The network information comprises a generator-node network incidence matrix A and a node admittance matrix YnetNode voltage UnActive power P of nodenAnd node reactive power QnThe method is characterized in that the step of calculating the disturbance power distribution coefficient of the synchronous generator set by combining the synchronous generator set information and the network information based on the disturbance power of the node j of the power system by the first calculation unit comprises the following steps:
according to the sub-transient reactance of the synchronous generator setx’ dgGenerating generator admittance matrix Ygen；
According to the terminal voltage U of each synchronous generator set g Generator terminal voltage vector Ugen；
According to generator admittance matrix YgenGenerating a generator-node association admittance matrix Y with the generator-node network association matrix Agn；
According to the node admittance matrix YnetAnd generator admittance matrix YgenGenerating a modified node admittance matrix Ynet ’The expression is as follows:
Figure 908417DEST_PATH_IMAGE001
according to node voltage UnActive power P of nodenAnd node reactive power QnGenerating a load admittance matrix YLPQThe expression is as follows:
Figure 577296DEST_PATH_IMAGE002
based on disturbance power DeltaP given to one node j of the power system in fault set informationjAnd injected perturbation power Δ PjNode j ofjCalculating a disturbance current vector Δ I of the power systemj_nThe expression is as follows:
Figure 836239DEST_PATH_IMAGE003
according to the terminal voltage vector UgenGenerator-node association admittance matrix YgnCorrecting the nodal admittance matrix Ynet ’Load admittance matrix YLPQThe disturbance current vector Δ Ij_nAnd disturbance power Δ PjCalculating disturbance power distribution coefficient K of synchronous generator setj_PDFThe calculation formula is as follows:
Figure 869530DEST_PATH_IMAGE004
wherein the synchronous generator set information includes a collected sub-transient reactance of the synchronous generator setx’ dgAnd terminal voltage U of synchronous generator setgG is the number of the generator, G is more than or equal to 1 and less than or equal to G, and G is the total number of the synchronous generator sets in the power system; the network information comprises a generator-node network incidence matrix A and a node admittance matrix Y which are collectednetNode voltage UnActive power P of nodenNode reactive power QnN is the node number, N is more than or equal to 1 and less than or equal to N, and N is the total number of the nodes in the power system.
8. The system of claim 6, wherein the second computing unit computing the new-energy generator set equivalent inertia based on the disturbance power of the node j of the power system in combination with the rotational inertia of the synchronous generator set and the new-energy generator set information comprises:
calculating the equivalent inertia J of the new energy generator set controlled by the virtual synchronizerv_eqThe formula of (1) is:
Jv_eq= Jv
calculating the equivalent inertia J of the new energy generator set controlled by the virtual inertiaw_eqThe formula of (1) is:
Figure 872121DEST_PATH_IMAGE005
in the formula, the new energy generator set information comprises a virtual inertia parameter J of the new energy generator set controlled by the virtual synchronizer in an acquisition modevV is the number of the new energy generator set controlled by the virtual synchronizer, V is more than or equal to 1 and less than or equal to V, V is the total number of the new energy generator set controlled by the virtual synchronizer in the power system, and the rated capacity S of the new energy generator set controlled by the virtual inertia is further includedwCoefficient of inertia support power kwInertia support input delayTime tdwW is the number of the new energy generator set controlled by the virtual inertia, W is more than or equal to 1 and less than or equal to W, W is the total number of the new energy generator sets controlled by the virtual inertia in the power system, and delta PjGiving disturbance power to a node j of the power system in the fault set information, wherein j is more than or equal to 1 and less than or equal to N, N is the total number of nodes in the power system, tcFor a given safety action time, J, in the fault set informationgG is larger than or equal to 1 and smaller than or equal to G, and G is the total number of the synchronous generator sets in the power system.
9. The system of claim 7, wherein the third computing unit computing the system equivalent moment of inertia of the power system according to the disturbance power distribution coefficient and the moment of inertia of the synchronous generator set and the equivalent inertia of the new energy generator set comprises:
calculating the minimum equivalent moment of inertia J of the power system according to the disturbance power distribution coefficient and the moment of inertia of the synchronous generator setj_eq_minThe calculation formula is as follows:
Figure 395506DEST_PATH_IMAGE006
in the formula, JgFor synchronizing the rotary inertia of the generator set, Kj_PDFgDisturbance power distribution coefficient K for synchronous generator setj_PDFG is more than or equal to 1 and less than or equal to G, and G is the total number of synchronous generator sets in the power system;
calculating the area equivalent rotational inertia J of the power system according to the disturbance power distribution coefficient and the rotational inertia of the synchronous generator set and the equivalent inertia of the new energy generator setj_eq_zoneThe calculation formula is as follows:
Figure 90929DEST_PATH_IMAGE007
in the formula, JjGiving a disturbance power Δ P to a node j of the power system in fault set informationjThen, the rotational inertia of the synchronous generator set and the equivalent inertia, K, of the new energy generator set in the region Z defined by the power systemj_PDFgDisturbance power distribution coefficient K for synchronous generator setj_PDFG is a synchronous generator set in a zone Z defined by the power system.
10. The system of claim 9, wherein the result analysis unit calculates a system equivalent inertia moment threshold value of the power system according to a maximum frequency deviation allowed by the power system and a rated angular velocity based on a disturbance power of a node j of the power system, and determines the inertia moment monitoring result of the power system according to the system equivalent inertia moment and the equivalent inertia moment threshold value comprises:
calculating a system equivalent moment inertia threshold J of the power system according to the maximum frequency deviation and the rated angular speed allowed by the power system based on the disturbance power of the node J of the power systemj_eq_thThe calculation formula is as follows:
Figure 332555DEST_PATH_IMAGE008
in the formula,. DELTA.PjGiven a disturbance power, t, for a node j of the power system in fault set informationcFor a given safety action time, Δ f, in the fault set informationmaxMaximum frequency deviation, ω, allowed for the power system0Is the rated angular speed of the power system;
comparing the equivalent moment of inertia threshold J of the systemj_eq_thAnd the minimum equivalent moment of inertia Jj_eq_minWhen J isj_eq_min＜Jj_eq_thWhen the moment of inertia of the power system is abnormal, when Jj_eq_min≥Jj_eq_thDetermining that the rotational inertia of the power system is normal;
comparing the equivalent moment of inertia threshold J of the systemj_eq_thAnd area equivalent moment of inertia Jj_eq_zoneWhen J isj_eq_zone＜Jj_eq_thWhen the moment of inertia of the power system is abnormal, when Jj_eq_zone≥Jj_eq_thAnd determining that the rotation of the power system is normal.
11. A computer-readable storage medium, characterized in that the storage medium stores a computer program for performing the method of any of the preceding claims 1 to 5.
12. An electronic device, characterized in that the electronic device comprises:
a processor;
a memory for storing the processor-executable instructions;
the processor is configured to read the executable instructions from the memory and execute the instructions to implement the method of any one of claims 1 to 5.
CN202111029515.0A 2021-09-03 2021-09-03 Method and system for monitoring inertia of power system Active CN113471972B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202111029515.0A CN113471972B (en) 2021-09-03 2021-09-03 Method and system for monitoring inertia of power system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111029515.0A CN113471972B (en) 2021-09-03 2021-09-03 Method and system for monitoring inertia of power system

Publications (2)

Publication Number Publication Date
CN113471972A true CN113471972A (en) 2021-10-01
CN113471972B CN113471972B (en) 2021-11-16

Family

ID=77867455

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111029515.0A Active CN113471972B (en) 2021-09-03 2021-09-03 Method and system for monitoring inertia of power system

Country Status (1)

Country Link
CN (1) CN113471972B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117233503A (en) * 2023-09-14 2023-12-15 国网湖北省电力有限公司电力科学研究院 Method and related device for testing inertia and damping of network-structured converter

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108390397A (en) * 2018-01-29 2018-08-10 国电南瑞科技股份有限公司 Large capacity multi-infeed DC mains frequency stablizes adaptive emergency control method
CN109524990A (en) * 2018-12-03 2019-03-26 三峡大学 A kind of virtual inertia configuration method based on Voronoi diagram center of gravity interpolation method
US20190222026A1 (en) * 2018-01-14 2019-07-18 Qingchang ZHONG Reconfiguration of Inertia, Damping and Fault Ride-Through for a Virtual Synchronous Machine
CN112484920A (en) * 2020-11-11 2021-03-12 中国电力科学研究院有限公司 System and method for monitoring rotational inertia of power system
CN112653130A (en) * 2020-12-07 2021-04-13 中国电力科学研究院有限公司 Method and system for determining frequency supporting capacity of power grid based on inertia ratio

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20190222026A1 (en) * 2018-01-14 2019-07-18 Qingchang ZHONG Reconfiguration of Inertia, Damping and Fault Ride-Through for a Virtual Synchronous Machine
CN108390397A (en) * 2018-01-29 2018-08-10 国电南瑞科技股份有限公司 Large capacity multi-infeed DC mains frequency stablizes adaptive emergency control method
CN109524990A (en) * 2018-12-03 2019-03-26 三峡大学 A kind of virtual inertia configuration method based on Voronoi diagram center of gravity interpolation method
CN112484920A (en) * 2020-11-11 2021-03-12 中国电力科学研究院有限公司 System and method for monitoring rotational inertia of power system
CN112653130A (en) * 2020-12-07 2021-04-13 中国电力科学研究院有限公司 Method and system for determining frequency supporting capacity of power grid based on inertia ratio

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117233503A (en) * 2023-09-14 2023-12-15 国网湖北省电力有限公司电力科学研究院 Method and related device for testing inertia and damping of network-structured converter
CN117233503B (en) * 2023-09-14 2024-03-29 国网湖北省电力有限公司电力科学研究院 Method and related device for testing inertia and damping of network-structured converter

Also Published As

Publication number Publication date
CN113471972B (en) 2021-11-16

Similar Documents

Publication Publication Date Title
Li et al. Wind in weak grids: Low-frequency oscillations, subsynchronous oscillations, and torsional interactions
CN111245014B (en) Virtual inertia-based power system control method
CN110350588A (en) A kind of double-fed blower grid-connected system dynamic power stability assessment method and system
CN112434936A (en) Power system inertia security domain evaluation method and system, electronic equipment and readable storage medium
CN110137948B (en) Method and device for evaluating sub-synchronous oscillation risk of doubly-fed wind power plant
CN113471972B (en) Method and system for monitoring inertia of power system
CN111224425A (en) Wind storage system black start frequency control method and system based on hierarchical predictive control
Xu et al. Sub-synchronous frequency domain-equivalent modeling for wind farms based on rotor equivalent resistance characteristics
Zheng et al. Transient stable region of power systems incorporating stochasticity of variable renewable energies and system contingencies
CN117394436A (en) Photovoltaic bearing capacity assessment method and system based on random scene analysis
CN113346484A (en) Power distribution network elasticity improving method and system considering transient uncertainty
CN110601215A (en) Dynamic reactive power support capability assessment method and system considering continuous commutation failure
CN115459310A (en) Hybrid energy storage capacity optimization method and system based on improved variational modal decomposition
CN114977191A (en) Static voltage stability analysis method and device and computer storage medium
CN111049158B (en) Method and system for determining broadband oscillation stability of power system based on spectrum radius
CN112564134B (en) Method, device, equipment and medium for configuring primary frequency modulation reserve capacity of power grid
Yang et al. Steady-state security region-based chance-constrained optimization for integrated energy systems
Zhao et al. Research on reliability assessment and multi-time scale improvement strategy of electricity-gas integrated energy system under cyber attack
CN112484920A (en) System and method for monitoring rotational inertia of power system
CN109088413B (en) Dynamic reactive power planning and site selection method and device for direct-current receiving-end power grid
CN111082454B (en) Method and system for obtaining oscillation risk quantitative index of power system
Sheng et al. Model Parameter Identification of Wind Farm's Primary Frequency Control based on Actual Power Response Characteristic
CN116561485B (en) Distribution transformer area photovoltaic capacity calculation method, device, equipment and medium
CN116388231B (en) Wind power cluster aggregation equivalence method based on frequency and wind speed
CN115630875B (en) Rotational inertia evaluation method and system of synchronous power grid

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
GR01 Patent grant
GR01 Patent grant