CN112668875A - Method for evaluating maximum power receiving proportion of multichannel power receiving system based on reactive margin - Google Patents

Method for evaluating maximum power receiving proportion of multichannel power receiving system based on reactive margin Download PDF

Info

Publication number
CN112668875A
CN112668875A CN202011565424.4A CN202011565424A CN112668875A CN 112668875 A CN112668875 A CN 112668875A CN 202011565424 A CN202011565424 A CN 202011565424A CN 112668875 A CN112668875 A CN 112668875A
Authority
CN
China
Prior art keywords
channel
power
power receiving
reactive
margin
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202011565424.4A
Other languages
Chinese (zh)
Inventor
刘继成
柳顺楠
张运厚
张文朝
宋丹
杨俊炜
李岩春
任普春
毕立松
赵伯铉
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.)
Northeast Branch Of State Grid Corp Of China
Beijing Kedong Electric Power Control System Co Ltd
Original Assignee
Northeast Branch Of State Grid Corp Of China
Beijing Kedong Electric Power Control System 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 Northeast Branch Of State Grid Corp Of China, Beijing Kedong Electric Power Control System Co Ltd filed Critical Northeast Branch Of State Grid Corp Of China
Priority to CN202011565424.4A priority Critical patent/CN112668875A/en
Publication of CN112668875A publication Critical patent/CN112668875A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • 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
    • Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
    • Y02E40/70—Smart grids as climate change mitigation technology in the energy generation sector
    • 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
    • Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
    • Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
    • Y04S10/00—Systems supporting electrical power generation, transmission or distribution
    • Y04S10/50—Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications

Abstract

The invention discloses a method for evaluating the maximum power receiving proportion of a multi-channel power receiving system based on reactive margin, which comprises the steps of establishing an inner channel model and an outer channel model of the multi-channel power receiving system; calculating a reactive margin index and a transient reactive distribution coefficient of an external channel according to an external channel model of the multi-channel power receiving system; calculating transient reactive power distribution coefficients of the inner channels according to the inner channel model of the multi-channel power receiving system; calculating the transient power margin of the multi-channel power receiving system according to the reactive power margin indexes and the transient reactive power distribution coefficients of the external channels; and calculating the maximum power receiving proportion of the multi-channel power receiving system based on the transient stability margin, the inner channel transient reactive power distribution coefficient and the load power factor of the multi-channel power receiving system. By the method, the receiving-end power grid power receiving proportion can be quickly estimated, quantitative analysis experience is provided for relevant personnel, and operating personnel can quickly establish a reasonable system operation mode.

Description

Method for evaluating maximum power receiving proportion of multichannel power receiving system based on reactive margin
Technical Field
The invention relates to a method for evaluating the maximum power receiving proportion of a multi-channel power receiving system based on reactive power margin, and belongs to the technical field of power systems.
Background
At present, a plurality of receiving-end power grids in China have the problem of voltage stability, and the problem of voltage stability can seriously restrict the power receiving capacity of the receiving-end power grids and hinder the transmission and distribution of electric energy. For a receiving-end large power grid, the voltage stability problem can be attributed to the large power receiving proportion and the insufficient supporting capability of an internal power supply. At present, the estimation of the power receiving capacity of a receiving-end power grid is mainly carried out through various simulation software, but a large amount of time is usually consumed for calculation, and the power receiving capacity of the power grid cannot be obtained quickly.
Disclosure of Invention
The invention aims to provide a method for evaluating the maximum power receiving ratio of a multi-channel power receiving system based on reactive power margin, which is used for realizing the rapid estimation of the power receiving ratio of a receiving-end power grid, providing quantitative analysis experience for related personnel and facilitating the rapid formulation of a reasonable system operation mode by operating personnel.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows:
the invention provides a method for evaluating the maximum power receiving proportion of a multi-channel power receiving system based on reactive power margin, which comprises the following steps:
establishing an inner channel model and an outer channel model of a multi-channel power receiving system;
calculating a reactive margin index and a transient reactive distribution coefficient of an external channel according to an external channel model of the multi-channel power receiving system; calculating transient reactive power distribution coefficients of the inner channels according to the inner channel model of the multi-channel power receiving system;
calculating the transient power margin of the multi-channel power receiving system according to the reactive power margin indexes and the transient reactive power distribution coefficients of the external channels;
and calculating the maximum power receiving proportion of the multi-channel power receiving system based on the transient stability margin, the inner channel transient reactive power distribution coefficient and the load power factor of the multi-channel power receiving system.
Further, the establishing of the internal and external channel models of the multi-channel power receiving system includes:
the method comprises the following steps that the interior of a power grid of the multi-channel power receiving system is simplified into a model that a generator set is connected to a load bus through a reactor, all loads of the power grid are concentrated on the load bus of the model, the generator set is a whole-grid equivalent unit, the equivalent unit impedance is the total parallel impedance of all starting units of the whole grid, and the generator set is connected to the load bus through equivalent boost variable impedance and equivalent line impedance, so that the generator set is an internal channel of the multi-channel power receiving system;
the multi-channel power receiving system is connected with an external power grid through alternating current and direct current channels, and the external power grid is equivalent to an infinite unit; for the alternating current channel, the infinite unit is connected with a power grid of the multi-channel power receiving system through equivalent impedance and line impedance, and all the alternating current channels are external channels of the multi-channel power receiving system.
Further, the calculating a reactive margin index and a transient reactive distribution coefficient of the external channel according to the external channel model of the multi-channel power receiving system includes:
the reactive margin index is calculated as:
Figure BDA0002860706490000021
wherein, KqiIs a reactive margin index, Q, of the ith external channeli0Reactive, Q, for normal mode delivery of the ith external channelimaxA reactive power transfer limit for the ith external channel;
the transient reactive power distribution coefficient is calculated as:
Figure BDA0002860706490000022
wherein x isiIs the total impedance of the ith external channel, and n is the number of external channels.
Further, the total impedance of the external channel is the sum of the equivalent impedance of the alternating current channel and the line impedance, wherein the equivalent impedance is obtained through a short circuit test, and the line impedance is the total parallel impedance of all lines of the alternating current channel.
Further, the external channel reactive power transfer limit is calculated as:
Figure BDA0002860706490000023
wherein the content of the first and second substances,
Figure BDA0002860706490000024
as the load power factor, EsIs the sending end equivalent unit potential.
Further, the calculating an internal channel transient reactive power distribution coefficient according to an internal channel model of the multi-channel powered system includes:
Figure BDA0002860706490000025
wherein, KGInner channel transient reactive power distribution coefficient, x0Is the total internal channel impedance, xiIs the total impedance of the ith external channel, and n is the number of external channels.
Further, the total internal channel impedance is the sum of the equivalent boost converter impedance and the equivalent line impedance:
Figure BDA0002860706490000026
Figure BDA0002860706490000027
wherein, XTFor equivalent step-up impedance, XLIs an equivalent line impedance, Qloss changeFor the total loss, Q, of the generatorloss totalAnd P is the total loss of the receiving-end power grid, P is the total active load of the receiving-end power grid, and Q is the total reactive load of the receiving-end power grid.
Further, the calculating a transient power margin of the multi-channel power receiving system according to the reactive power margin indicator and the transient reactive power distribution coefficient of each external channel includes:
calculating the voltage stability power receiving capability index of each external channel:
Ki＝αKqi-βKxi
wherein, KiThe voltage stability receiving capacity index of the ith external channel is defined, and alpha and beta are correlation factors between the reactive margin and the transient reactive distribution coefficient;
calculating a multichannel margin average value:
Figure BDA0002860706490000031
calculating a multichannel margin standard deviation:
Figure BDA0002860706490000032
calculating a multi-channel transient power margin:
Figure BDA0002860706490000033
wherein eta and gamma are correlation factors of the multichannel margin average value and the standard deviation.
Further, the calculating the maximum power receiving ratio of the multi-channel power receiving system based on the transient stability margin, the internal channel transient reactive power distribution coefficient and the load power factor of the multi-channel power receiving system includes:
Figure BDA0002860706490000034
wherein, KGThe transient reactive power distribution coefficient of the inner channel,
Figure BDA0002860706490000035
the load power factor is P, the total active load of the receiving end power grid is P, and the power receiving is positive.
Further, α, β, η, γ are calculated as follows:
PSD-BPA electromechanical transient simulation software is adopted to calculate the conveying capacity in four modes, and the total impedance, the reactive margin index, the transient reactive distribution coefficient and the power receiving proportion of the inner channel and the outer channel in the corresponding modes are obtained, and alpha, beta, eta and gamma are solved by a simultaneous equation set;
the four modes are four modes in which the power receiving proportion reaches the limit under the conditions that the initial reactive power of each channel of the actual power grid is different and the starting mode of the generator in the power grid is different.
The invention achieves the following beneficial effects:
the invention provides a method for evaluating the maximum power receiving proportion of a multichannel power receiving system based on reactive power margin, which comprises the steps of establishing a single-section voltage stable power receiving capacity index and a multi-section voltage stable power receiving capacity index in three aspects of a reactive power margin index, a load power factor and a transient reactive power distribution coefficient; the method can realize the rapid estimation of the receiving-end power grid power receiving proportion, provides quantitative analysis experience for related personnel, improves the simplicity of the calculation process and the practicability in the engineering field on the premise of ensuring the scientific and reasonable evaluation process, and is beneficial to operators to rapidly formulate a reasonable system operation mode.
Drawings
Fig. 1 is a flowchart of a method for evaluating a maximum power receiving ratio of a multi-channel power receiving system based on a reactive margin according to the present invention;
fig. 2 is a power grid structure diagram of a certain area in the embodiment of the invention.
Detailed Description
The invention is further described below. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.
The invention provides a method for evaluating the maximum power receiving proportion of a multi-channel power receiving system based on reactive power margin, which comprises the following steps:
establishing an inner channel model and an outer channel model of a multi-channel power receiving system;
calculating a reactive margin index and a transient reactive distribution coefficient of an external channel according to an external channel model of the multi-channel power receiving system; calculating transient reactive power distribution coefficients of the inner channels according to the inner channel model of the multi-channel power receiving system;
calculating the transient power margin of the multi-channel power receiving system according to the reactive power margin indexes and the transient reactive power distribution coefficients of the external channels;
and calculating the maximum power receiving proportion of the multi-channel power receiving system based on the transient stability margin, the inner channel transient reactive power distribution coefficient and the load power factor of the multi-channel power receiving system.
Specifically, establishing an internal channel model and an external channel model of a multi-channel power receiving system includes:
the internal reactive support of the power grid of the multi-channel power receiving system is mainly borne by a generator, and factors such as a phase modulator are temporarily ignored. The interior of the power grid can be simplified into a model that a unit is connected to a load bus through a reactor. All loads of the power grid are concentrated on a load bus of the model, the unit is a full-grid equivalent unit which can be approximately considered as an infinite unit, the internal potential is 1, and the equivalent unit impedance is the total parallel impedance of all the startup units of the full-grid, and can be approximately ignored for the large power grid. The equivalent boost transformation impedance and the equivalent line impedance from the generator set to the load bus can be calculated by the following formulas:
Figure BDA0002860706490000041
Figure BDA0002860706490000042
wherein, XTFor equivalent step-up impedance, XLIs an equivalent line impedance, Qloss changeFor the total loss, Q, of the generatorloss totalAnd P is the total loss of the receiving-end power grid, P is the total active load of the receiving-end power grid, and Q is the total reactive load of the receiving-end power grid. Qloss change，Qloss totalBoth P and Q can be obtained from actual grid operation.
The powered system is typically connected to an external power grid via ac and dc channels. Generally, the external grid is much larger than the receiving grid, so the external grid can be equivalent to an infinite unit. For an alternating current channel, an infinite unit is connected with a receiving end power grid through equivalent impedance and line impedance, the equivalent impedance is obtained through a short-circuit test, and the line impedance is the total parallel impedance of all lines of a certain alternating current channel. For the direct current channel, since the direct current channel does not provide reactive support capability in the transient process, the direct current channel is equivalent to a negative load.
In summary, the multi-channel power receiving system can be equivalent to a load point and connected to a plurality of infinite units, the inside of the power grid of the multi-channel power receiving system is equivalent to an internal channel, and both the ac channel and the dc channel of the power grid of the multi-channel power receiving system connected to the external power grid are external channels. The overall impedance of the outer channel is relatively large and the overall impedance of the inner channel is extremely small. The external channels in the present invention only consider ac channels.
Specifically, the method for calculating the reactive margin index and the transient reactive distribution coefficient of the external channel according to the external channel model of the multi-channel power receiving system includes:
(a) index of reactive margin
The reactive margin mainly describes a difference value between a certain channel and a reactive transmission limit, and can reflect the reactive power providing capability of the channel, and a calculation formula is as follows:
Figure BDA0002860706490000043
in the formula, KqiIs a reactive margin index, Q, of the ith external channeli0Obtaining the reactive power for the normal mode transmission of the ith external channel by reading the actual power flow of the power grid, QimaxThe reactive power transfer limit for the ith external channel. The smaller the reactive margin index is, the weaker the disturbance bearing capacity of the section is, and the lower the voltage stability level of the system is.
The reactive delivery limit is calculated as follows:
Figure BDA0002860706490000051
wherein the content of the first and second substances,
Figure BDA0002860706490000052
as the load power factor, EsIs the potential of the sending end equivalent unit, and 1, x is taken during calculationiIs the total impedance of the ith outer channel.
Load power factor
According to the reactive power transmission limit calculation formula, under the condition determined by the grid structure, the section reactive power transmission limit and the load power factor are in a negative correlation relationship, and the section reactive power transmission limit is greatly increased when the load power factor is reduced. After short circuit impact, the induction motor slip will increase according to the load characteristics of the induction motor, and the reduction of the load bus voltage will result in the continuous increase of the reactive demand of the motor and thus the reduction of the load power factor. Establishing a load power factor indicator
Figure BDA0002860706490000053
As one of the indicators for evaluating the power receiving capability of a single channel.
(b) Transient reactive power distribution coefficient
After disturbance occurs, a machine set inside the power grid generates reactive power, the external channel provides reactive power for the receiving-end power grid, reactive power distribution and line impedance are in a negative correlation relationship, and for the single external-channel receiving-end power grid, the reactive power distribution and the ratio of the total impedance of the external channel to the total impedance of the internal channel are in direct proportion; for a plurality of external channels, the transient reactive power distribution coefficient is set as follows:
Figure BDA0002860706490000054
wherein x isiIs the total impedance of the ith external channel, and n is the total number of external channels.
Calculating the voltage stability power receiving capability index of each external channel according to the reactive margin index and the transient reactive distribution coefficient of each external channel, and the method comprises the following steps:
Ki＝αKqi-βKxi
in the formula, KiAnd alpha and beta are correlation factors between the reactive margin index and the transient reactive distribution coefficient.
Specifically, the calculating of the transient reactive power distribution coefficient of the inner channel according to the inner channel model of the multi-channel power receiving system includes:
for the internal passage, the main function is reactive support, and the index K is passedGTo represent the internal channel transient reactive power distribution coefficient:
Figure BDA0002860706490000055
wherein x is0Is the total internal channel impedance, xiIs the total impedance of the ith external channel, and n is the number of external channels.
Specifically, the method for calculating the transient power margin of the multi-channel power receiving system based on the voltage stabilization power receiving capability of each external channel includes:
the receiving-end power grid supplies power through a plurality of external channels, the voltage stability level of the receiving-end power grid is related to the single-channel transient power margin distribution condition, the margin balance among the single channels is better, and the receiving-end power grid is higher in power receiving capacity. And representing the multichannel transient power margin index by adopting the incidence relation of the sum of the multichannel margin mean value and the multichannel margin standard deviation.
(a) Mean value of multichannel margin
The index mainly reflects the arithmetic mean of the margins of a plurality of channels:
Figure BDA0002860706490000061
and n is the number of external channels of the receiving-end power grid.
(b) Multi-channel margin standard deviation
The index mainly reflects the standard deviation of the margins of a plurality of channels:
Figure BDA0002860706490000062
(c) multi-channel transient power margin
Figure BDA0002860706490000063
In the formula, eta and gamma are correlation factors of the multichannel margin average value and the standard deviation.
Specifically, based on the transient stability margin of the multi-channel powered system, the maximum powered proportion of the multi-channel powered system is calculated by the internal channel transient reactive power distribution coefficient and the load power factor, and the method comprises the following steps:
Figure BDA0002860706490000064
wherein, P is the total active load of the receiving end power grid, and the power receiving is positive.
Examples
The actual power grid structure of a certain area is shown in fig. 2, a receiving-end power grid is equivalent to an internal channel, the receiving-end power grid is provided with three external alternating current receiving channels which are equivalent to external channels 1, 2 and 3 respectively, and the maximum power receiving proportion of the receiving-end power grid is calculated according to the initial power flow. The specific implementation process is as follows:
PSD-BPA electromechanical transient simulation software is adopted to calculate the conveying capacity in four modes to obtain corresponding indexes, and the indexes are shown in tables 1, 2, 3 and 4. The four modes are respectively four modes that the power receiving proportion reaches the limit under the conditions that the initial reactive power of each channel of the actual power grid is different and the starting mode of the generator in the power grid is different, and the four variables of alpha, beta, eta and gamma are solved through the power receiving proportion of the four modes and each index by a simultaneous equation set.
TABLE 1 mode calculation values of each channel index
Figure BDA0002860706490000065
TABLE 2 calculated values of the indexes of the channels in the second mode
Figure BDA0002860706490000071
TABLE 3 calculated values of the indexes of the three channels
Figure BDA0002860706490000072
TABLE 4 calculated values of the indexes of the four channels
Figure BDA0002860706490000073
Wherein, the power factor of the receiving end power grid is calculated according to 0.9.
According to the initial power flow and the index of four modes, corresponding four coefficients can be solved:
α＝0.16
β＝0.01
η＝12.52
γ＝-0.049
according to the four parameters, when the actual power grid initial parameters are shown in table 5, the power receiving proportion is calculated according to the method of the invention, the load power factor is still considered according to 0.9, and the direct current is received at 6000 MW.
TABLE 5 actual grid initial parameters
Figure BDA0002860706490000074
Figure BDA0002860706490000081
The power receiving ratio is calculated to be about 51%, and the maximum power receiving ratio is 45% by simulation, with an error of about 12%.
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 (10)

1. The method for evaluating the maximum power receiving proportion of the multi-channel power receiving system based on the reactive margin is characterized by comprising the following steps of:
establishing an inner channel model and an outer channel model of a multi-channel power receiving system;
calculating a reactive margin index and a transient reactive distribution coefficient of an external channel according to an external channel model of the multi-channel power receiving system; calculating transient reactive power distribution coefficients of the inner channels according to the inner channel model of the multi-channel power receiving system;
calculating the transient power margin of the multi-channel power receiving system according to the reactive power margin indexes and the transient reactive power distribution coefficients of the external channels;
and calculating the maximum power receiving proportion of the multi-channel power receiving system based on the transient stability margin, the inner channel transient reactive power distribution coefficient and the load power factor of the multi-channel power receiving system.
2. The reactive margin-based method for estimating the maximum power receiving ratio of a multi-channel power receiving system according to claim 1, wherein the establishing an inner channel model and an outer channel model of the multi-channel power receiving system comprises:
the method comprises the following steps that the interior of a power grid of the multi-channel power receiving system is simplified into a model that a generator set is connected to a load bus through a reactor, all loads of the power grid are concentrated on the load bus of the model, the generator set is a whole-grid equivalent unit, the equivalent unit impedance is the total parallel impedance of all starting units of the whole grid, and the generator set is connected to the load bus through equivalent boost variable impedance and equivalent line impedance, so that the generator set is an internal channel of the multi-channel power receiving system;
the multi-channel power receiving system is connected with an external power grid through alternating current and direct current channels, and the external power grid is equivalent to an infinite unit; for the alternating current channel, the infinite unit is connected with a power grid of the multi-channel power receiving system through equivalent impedance and line impedance, and all the alternating current channels are external channels of the multi-channel power receiving system.
3. The method for estimating maximum power receiving proportion of a multi-channel power receiving system based on reactive power margin as claimed in claim 2, wherein the calculating the reactive power margin indicator and the transient reactive power distribution coefficient of the external channel according to the external channel model of the multi-channel power receiving system comprises:
the reactive margin index is calculated as:
Figure FDA0002860706480000011
wherein, KqiIs the ith outer partReactive margin indicator, Q, of the channeli0Reactive, Q, for normal mode delivery of the ith external channelimaxA reactive power transfer limit for the ith external channel;
the transient reactive power distribution coefficient is calculated as:
Figure FDA0002860706480000012
wherein x isiIs the total impedance of the ith external channel, and n is the number of external channels.
4. The reactive margin-based method for evaluating the maximum power receiving proportion of a multichannel power receiving system as claimed in claim 3, wherein the total impedance of the external channels is the sum of the equivalent impedance of the AC channels and the line impedance, wherein the equivalent impedance is obtained by a short circuit test, and the line impedance is the total parallel impedance of all lines of the AC channels.
5. The reactive margin-based multi-channel powered system maximum power ratio evaluation method of claim 3, wherein the outer channel reactive power transfer limit is calculated as:
Figure FDA0002860706480000021
wherein the content of the first and second substances,
Figure FDA0002860706480000022
as the load power factor, EsIs the sending end equivalent unit potential.
6. The method for estimating maximum power ratio of a multi-channel power receiving system based on reactive power margin as claimed in claim 2, wherein the calculating an inner-channel transient reactive power distribution coefficient according to an inner-channel model of the multi-channel power receiving system comprises:
Figure FDA0002860706480000023
wherein, KGInner channel transient reactive power distribution coefficient, x0Is the total internal channel impedance, xiIs the total impedance of the ith external channel, and n is the number of external channels.
7. The reactive margin-based method for evaluating the maximum power receiving proportion of a multi-channel power receiving system according to claim 6, wherein the total internal channel impedance is the sum of an equivalent boost converter impedance and an equivalent line impedance:
Figure FDA0002860706480000024
Figure FDA0002860706480000025
wherein, XTFor equivalent step-up impedance, XLIs an equivalent line impedance, Qloss changeFor the total loss, Q, of the generatorloss totalAnd P is the total loss of the receiving-end power grid, P is the total active load of the receiving-end power grid, and Q is the total reactive load of the receiving-end power grid.
8. The method for estimating maximum power receiving proportion of a multi-channel power receiving system based on reactive power margin as claimed in claim 3, wherein the calculating the transient power margin of the multi-channel power receiving system according to the reactive power margin indicator and the transient reactive power distribution coefficient of each external channel comprises:
calculating the voltage stability power receiving capability index of each external channel:
Ki＝αKqi-βKxi
wherein, KiThe voltage stability receiving capacity index of the ith external channel is defined, and alpha and beta are correlation factors between the reactive margin and the transient reactive distribution coefficient;
calculating a multichannel margin average value:
Figure FDA0002860706480000026
calculating a multichannel margin standard deviation:
Figure FDA0002860706480000027
calculating a multi-channel transient power margin:
Figure FDA0002860706480000028
wherein eta and gamma are correlation factors of the multichannel margin average value and the standard deviation.
9. The method for estimating the maximum power receiving proportion of a multi-channel power receiving system based on the reactive margin of claim 8, wherein the calculating the maximum power receiving proportion of the multi-channel power receiving system based on the transient stability margin, the inner-channel transient reactive power distribution coefficient and the load power factor of the multi-channel power receiving system comprises:
Figure FDA0002860706480000031
wherein, KGThe transient reactive power distribution coefficient of the inner channel,
Figure FDA0002860706480000032
the load power factor is P, the total active load of the receiving end power grid is P, and the power receiving is positive.
10. The reactive margin-based multi-channel powered system maximum power ratio evaluation method of claim 8, wherein α, β, η, γ are calculated as follows:
PSD-BPA electromechanical transient simulation software is adopted to calculate the conveying capacity in four modes, and the total impedance, the reactive margin index, the transient reactive distribution coefficient and the power receiving proportion of the inner channel and the outer channel in the corresponding modes are obtained, and alpha, beta, eta and gamma are solved by a simultaneous equation set;
the four modes are four modes in which the power receiving proportion reaches the limit under the conditions that the initial reactive power of each channel of the actual power grid is different and the starting mode of the generator in the power grid is different.
CN202011565424.4A 2020-12-25 2020-12-25 Method for evaluating maximum power receiving proportion of multichannel power receiving system based on reactive margin Pending CN112668875A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202011565424.4A CN112668875A (en) 2020-12-25 2020-12-25 Method for evaluating maximum power receiving proportion of multichannel power receiving system based on reactive margin

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202011565424.4A CN112668875A (en) 2020-12-25 2020-12-25 Method for evaluating maximum power receiving proportion of multichannel power receiving system based on reactive margin

Publications (1)

Publication Number Publication Date
CN112668875A true CN112668875A (en) 2021-04-16

Family

ID=75409379

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202011565424.4A Pending CN112668875A (en) 2020-12-25 2020-12-25 Method for evaluating maximum power receiving proportion of multichannel power receiving system based on reactive margin

Country Status (1)

Country Link
CN (1) CN112668875A (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20030035275A (en) * 2001-10-30 2003-05-09 한국전력공사 The Method for Online Transient Stability Estimation of Power System and It's System
WO2014173131A1 (en) * 2013-04-23 2014-10-30 国家电网公司 Large power grid overall situation on-line integrated quantitative evaluation method based on response
CN108512219A (en) * 2018-03-14 2018-09-07 国家电网公司华中分部 A kind of multichannel receiving-end system under Voltage Stability Constraints is by electric energy power comprehensive estimation method
CN111987720A (en) * 2020-08-26 2020-11-24 国网江苏省电力有限公司 Method for evaluating power receiving and power supply margin intervals of receiving-end power grid under constraint of multichannel quota

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20030035275A (en) * 2001-10-30 2003-05-09 한국전력공사 The Method for Online Transient Stability Estimation of Power System and It's System
WO2014173131A1 (en) * 2013-04-23 2014-10-30 国家电网公司 Large power grid overall situation on-line integrated quantitative evaluation method based on response
CN108512219A (en) * 2018-03-14 2018-09-07 国家电网公司华中分部 A kind of multichannel receiving-end system under Voltage Stability Constraints is by electric energy power comprehensive estimation method
CN111987720A (en) * 2020-08-26 2020-11-24 国网江苏省电力有限公司 Method for evaluating power receiving and power supply margin intervals of receiving-end power grid under constraint of multichannel quota

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
张运厚 等: "考虑无功裕度的受端电网暂态电压稳定性控制方法研究", 可再生能源, 31 January 2022 (2022-01-31) *
李姝彤: "考虑风机低穿特性下送端常规机组最小开机方式研究", 中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑, 15 July 2021 (2021-07-15) *

Similar Documents

Publication Publication Date Title
CN110932281A (en) Multi-section cooperative correction method and system based on quasi-steady-state sensitivity of power grid
CN108448566B (en) Online hybrid simulation method and system for power system
CN110365019B (en) Multi-terminal direct-current power distribution network converter capacity configuration method and system
CN113890039B (en) Multi-terminal flexible direct-current power distribution network power flow scheduling optimization method
CN110048410A (en) Realize the frequency conversion load control method of network of ship stable operation
CN110187239B (en) Low-voltage distribution network line loss and electricity stealing and leakage point calculation method based on straight algorithm
Miu et al. Impact studies of unbalanced multi-phase distribution system component models
CN112596020A (en) Method and related device for correcting running errors of intelligent electric meters in transformer area
CN117117918A (en) Source network load storage optimization operation method and device
CN112668875A (en) Method for evaluating maximum power receiving proportion of multichannel power receiving system based on reactive margin
CN107482676B (en) Method and device for determining maximum permeability of distributed power supply considering volatility
CN115411735A (en) Method, system and equipment for calculating expected non-supplied electric quantity of power distribution network
CN112003288B (en) Intelligent voltage adjustment method and device for power grid operation mode
CN114285079A (en) Method and system for quickly estimating transient overvoltage caused by alternating current-direct current fault disturbance
CN113722678A (en) Transformer area line loss calculation method, system, storage medium and calculation device
CN113471972A (en) Method and system for monitoring inertia of power system
CN113300397A (en) Alternating current-direct current reactive power exchange reference value optimization method and system
CN112564134A (en) Method, device, equipment and medium for configuring primary frequency modulation reserve capacity of power grid
CN108551164B (en) Voltage stability control method and device for direct-current micro-grid
CN110912170A (en) Converter grounding scheme selection method and system for low-voltage direct-current power utilization system
CN111784086A (en) Power supply scheme evaluation method and system for direct-current power distribution and utilization system
CN112202191B (en) Hybrid direct-current transmission receiving-end power grid access method and system
CN117200266B (en) Distribution line photovoltaic collection point energy storage capacity configuration method, device and equipment
CN109713677B (en) Power grid optimal power flow model establishing method and device and electronic equipment
CN113300352B (en) Short-circuit current prevention control method and device considering safety and stability quota constraint

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