CN107123983B - Substation access scheme auxiliary evaluation method based on security domain - Google Patents

Substation access scheme auxiliary evaluation method based on security domain Download PDF

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CN107123983B
CN107123983B CN201710232120.8A CN201710232120A CN107123983B CN 107123983 B CN107123983 B CN 107123983B CN 201710232120 A CN201710232120 A CN 201710232120A CN 107123983 B CN107123983 B CN 107123983B
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power system
security domain
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CN107123983A (en
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苏寅生
李鹏
刘春晓
曾沅
张松涛
秦超
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Tianjin University
China Southern Power Grid Co Ltd
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China Southern Power Grid Co Ltd
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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • 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
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Abstract

The invention discloses a transformer substation access scheme auxiliary evaluation method based on a security domain, which comprises the following steps: obtaining state information in the current operation mode through load flow calculation to generate an admittance matrix under the grid structure; obtaining a matrix expression form of a node injection equation, and determining a decision parameter space by a control variable of a system so as to construct a corresponding static voltage security domain boundary; analyzing the stability margin of the power system, finding the boundary with the minimum stability margin in the current operation mode of the power system, acquiring parameter information corresponding to the boundary, and determining an optimal index for the transformer substation; accessing a newly-invested substation at a priority access point of the substation on the basis of an original network structure of the power system, and converting a PQ node at the access point into a PV node; and under the condition that the parameters of the transformer substations which are put into the transformer substations are consistent, constructing a security domain of the electric power system corresponding to the access scheme of the transformer substations again, and comparing the advantages and disadvantages of different access schemes through stability margin analysis to determine the scheme as a final scheme.

Description

Substation access scheme auxiliary evaluation method based on security domain
Technical Field
The invention belongs to the field of power grid planning, and particularly relates to the field of transformer substation operation planning.
Background
The intelligent substation is used as a physical foundation of the intelligent power grid and runs through the whole construction process of the intelligent power grid. With the continuous development and progress of society and economy, the basic requirements of power users in various industries on power systems have been changed to be safer, more reliable and more economical, a transformer substation is taken as an important part of the power systems and takes the responsibility of being the most important energy transmission point in power transmission and distribution equipment, whether the planning design is reasonable or not and whether the planning design can adapt to the severe fluctuation of loads or not is extremely important, so that the load development requirements in a plurality of years in the future are met, and therefore, the optimization analysis and evaluation technology of the transformer substation access system is one of important contents in the power system operation planning research.
Compared with the traditional transformer substation access design method, namely the point-by-point method, the Security Region (SR) method which is developed rapidly in recent years can effectively overcome the defect of the point-by-point method. The SR corresponds to the network of the system one by one and does not depend on the running state of the system; after the SR boundary is calculated, a relevant security check can be performed by determining whether the current injection of the system is located within the SR. Meanwhile, the SR can give the relative position of the current operating point in the domain so as to represent the safety and stability margin of the whole system.
The node voltage out-of-limit problem in the power system is worth paying attention, and the existing security domain for researching node voltage amplitude constraint only has a reactive static security domain. Variables in a decision space of the reactive static security domain are node reactive power injection vectors, and the reactive security domain in a hyper-polyhedral form on a high-dimensional space is given based on a mapping relation between an expression voltage vector and a reactive power vector in a decoupling load flow equation. The required reactive static security domain is composed of a plurality of pairs of approximately parallel hyperplanes, and is very concise. And the domain corresponds to the network topology one to one and is completely irrelevant to the operation mode, so that offline calculation can be performed on application, and the method is practical online and has outstanding advantages. However, because the decoupling load is based on decoupling load flow, the influence of active injection on voltage is ignored, so that the error is sometimes large, and the requirements of online safety monitoring, defense and control cannot be met.
In recent years, a great deal of research has been conducted on Static Voltage Security Region (SVSR) and its related applications. Research has found that the boundaries of the SVSR can be represented by one or more hyperplanes within the scope of engineering interest. Previous research on SVSR has never been applied to the assessment problem of substation access schemes. How to adopt the method of the security domain provides an auxiliary decision for the scheme of the substation access system, and further exploration is needed.
Disclosure of Invention
On the basis of a reactive static security domain, the static voltage security domain with node voltage constraint is researched and calculated based on an alternating current power flow model, a security domain-based substation access scheme auxiliary evaluation method is provided, an approximate analytical expression of a static voltage security domain boundary capable of meeting the requirements of engineering practical application is obtained, and further, the voltage problems of system nodes of different substation access schemes are analyzed, and auxiliary decision making is provided for substation operation planning. In order to solve the technical problem, the invention provides a transformer substation access scheme auxiliary evaluation method based on a security domain, which comprises the following steps:
step one, obtaining state information (V, theta) under a current operation mode through load flow calculation according to power system data, and generating an admittance matrix under the grid structure; wherein V is the node voltage amplitude, and theta is the node voltage phase angle;
step two, obtaining a matrix expression form of the node injection equation by using the admittance matrix obtained in the step one, and determining a decision parameter space by the control variable of the power system
Figure BDA0001266742260000021
Thereby constructing a corresponding quiescent voltage safety domain boundary;
step three, analyzing the stability margin of the power system according to the static voltage security domain obtained in the step two; finding a boundary with the minimum stability margin in the current operation mode of the power system, acquiring parameter information corresponding to the boundary, and determining an optimal selection index of an input substation, wherein the optimal selection index of the input substation is as follows: the sum of the absolute value of the product of the coefficient and the active value corresponding to the active parameter and the absolute value of the product of the coefficient and the reactive value corresponding to the reactive parameter; sequencing the preferred indexes of the input transformer substations, and taking N nodes with large preferred index values of the input transformer substations as the preferred access points of the transformer substations, wherein the value of N is 2-10;
setting the original network structure of the power system as a scene A, and on the basis of the original network structure of the power system, switching the priority access point of the substation determined in the step three into the newly-added substation to obtain a scene B, and converting the PQ node at the access point into a PV node;
and fifthly, under the condition that the parameters of the transformer substations which are put into the transformer substations are consistent, constructing a security domain of the power system corresponding to the N transformer substation access schemes of the scene B by using the method provided by the step two, comparing the stability margin values of the power systems of the N transformer substation access schemes and the power system of the scene A through stability margin analysis, and finally determining the scheme as the transformer substation access scheme if the power system with the maximum stability margin value is one of the transformer substation access schemes in the scene B, otherwise, not considering the transformer substations accessed in the power system.
Further, in the second step, the method for constructing the static voltage safety domain specifically includes:
setting: the power system is provided with n-1 nodes and nb branches, wherein the node 0 is a loose node and is provided with g +1 generator nodes; representing a set of generator nodes and substation nodes except for a relaxation node by S; representing a set of load nodes by L;
in a small neighborhood of the power system operating point V equal to 1 and θ equal to 0, cos θ is usedij＝1,sinθij＝θi-θjProcessing an alternating current equation to obtain a formula (2), wherein the alternating current equation is shown as a formula (1):
Figure BDA0001266742260000022
in the formula (1), Pij、QijActive and reactive power transmitted for line ij; vi、VjThe voltage amplitudes of the nodes i and j are respectively; thetai、θjThe phase angles of the voltages, θ, at nodes i, j, respectivelyij＝θi-θj；Gij、BijIs the corresponding element of the admittance matrix;
Figure BDA0001266742260000023
applying kirchhoff's theorem to the node i to obtain:
Figure BDA0001266742260000031
in the formula (3), Pi、QiActive power injection and reactive power injection for a node i;
writing equation (3) in matrix form:
Figure BDA0001266742260000032
in the formula (4), G and B are n × n order matrixes respectively, wherein G is a real part of an admittance matrix, and B is an imaginary part of the admittance matrix, and are constants; in the power flow calculation, an active power injection P and a reactive power injection Q are both nodes with given quantities, called PQ nodes, and the active power injection P and the node voltage amplitude V of the nodes are both nodes with given quantities, called PV nodes;
since the mapping from the V- θ space to the P-Q space is many-to-one, the power system operates near a point (V1, θ 0), and there is a one-to-one mapping relationship from the V- θ space to the P-Q space in a small neighborhood of the operating point, equation (4) is transformed into a matrix form as follows:
Figure BDA0001266742260000033
in formula (5), the PV junction and PQ junction are separated, A, B, C, D, E, F, G, H and I are block matrices with the order of n × n, n × n (n-g), n × g, (n-g) × n, (n-g) x (n-g), (n-g) x g, g × n (n-g), g × g, respectively;
the following equation (5) yields:
△VG＝G·△P+H·△QL+I·△QG(6)
△VL＝D·△P+E·△QL+F·△QG(7)
the following equation (6) yields:
△QG＝I-1·△VG-I-1·G·△P-I-1·H·△QL(8)
bringing formula (7) into formula (8) to obtain:
△VL＝(D-F·I-1·G)·△P+(E-F·I-1·H)·△QL+F·I-1·△VG(9)
is provided with
Figure BDA0001266742260000034
Is the upper voltage amplitude limit of the load node i,
Figure BDA0001266742260000035
is the present voltage of the load node i, P0，Q0And VG 0Respectively representing the values of corresponding quantities under the current operating condition, and the row vector s is represented by a matrix (D-F.I) of the voltage amplitude of the node I in the formula (9)-1·G)、(E-F·I-1H) and F.I-1The corresponding row vector in (1); then there are:
Figure BDA0001266742260000036
the final finish of formula (10) is:
Figure BDA0001266742260000037
in the formula (11), α, β and λ are all static security domain boundary coefficients;
thus, the static security domain of the upper voltage limit of the load node i is defined as:
Figure BDA0001266742260000041
similarly, the static security domain of the lower voltage limit of the load node i:
Figure BDA0001266742260000042
the static voltage security domain of the whole power system is the intersection of the static voltage security domains that the voltage upper and lower limit constraints of all the nodes are satisfied, namely:
Figure BDA0001266742260000043
in the third step, the calculation method of the stability margin value of the power system is as follows:
and C, calculating the node stability margin according to the security domain boundary coefficient obtained in the step II as follows:
Figure BDA0001266742260000044
in the formula (15), srmjIf the numerical value is positive, the current power system is safe, if the numerical value is larger, the stability margin of the current power system operation mode is larger, and the node j belongs to a load node;
the stability margin value of the power system is the minimum margin value corresponding to all boundaries; the stability margin value SRM calculation formula of the power system is as follows:
SRM＝min(srmj)(j∈L) (16)
in the third step, the calculation formula of the preferred indexes of the transformer substation is as follows:
OISA＝|αiPi|+|βiQi|(i∈L) (17)
compared with the prior art, the invention has the beneficial effects that:
at present, the existing substation access scheme evaluation method belongs to the category of a point-by-point method, and the influence of the planning scheme on the overall operation safety level of a power grid is difficult to provide. The method can effectively solve the defects, adopts a security domain method to identify weak nodes of the power grid in a certain operation mode, and provides a substation access system scheme. And comparing the improvement conditions of different substation access schemes on the SVSR margin of the system to obtain a better substation access scheme.
Drawings
Fig. 1 is a flow of a transformer substation access system auxiliary evaluation method provided by the invention;
FIG. 2 is a wiring diagram of a 118 node system provided by the present invention;
FIG. 3 is a SVSR over a 2-dimensional space for a system provided by the present invention;
FIG. 4 is a comparison of margin information provided by the present invention.
Detailed Description
The technical solutions of the present invention are further described in detail with reference to the accompanying drawings and specific embodiments, which are only illustrative of the present invention and are not intended to limit the present invention.
As shown in fig. 1, the present invention provides 1 a transformer substation access scheme auxiliary evaluation method based on a security domain, including the following steps:
step one, obtaining state information (V, theta) under a current operation mode through load flow calculation according to power system data, and generating an admittance matrix under the grid structure; wherein V is the node voltage amplitude, and theta is the node voltage phase angle; the present invention is exemplified by an IEEE118 node system, as shown in fig. 2.
Step two, obtaining a matrix expression form of the node injection equation by using the admittance matrix obtained in the step one, and determining a decision parameter space by the control variable of the power system
Figure BDA0001266742260000051
Thereby constructing a corresponding quiescent voltage safety domain boundary; the specific contents are as follows:
setting: the power system is provided with n-1 nodes and nb branches, wherein the node 0 is a loose node and is provided with g +1 generator nodes; representing a set of generator nodes and substation nodes except for a relaxation node by S; representing a set of load nodes by L;
in a small neighborhood of the power system operating point V equal to 1 and θ equal to 0, cos θ is usedij＝1,sinθij＝θi-θjProcessing an alternating current equation to obtain a formula (2), wherein the alternating current equation is shown as a formula (1):
Figure BDA0001266742260000052
in the formula (1), Pij、QijActive and reactive power transmitted for line ij; vi、VjThe voltage amplitudes of the nodes i and j are respectively; thetai、θjThe phase angles of the voltages, θ, at nodes i, j, respectivelyij＝θi-θj；Gij、BijIs the corresponding element of the admittance matrix;
Figure BDA0001266742260000053
applying kirchhoff's theorem to the node i to obtain:
Figure BDA0001266742260000054
in the formula (3), Pi、QiActive power injection and reactive power injection for a node i;
writing equation (3) in matrix form:
Figure BDA0001266742260000055
in the formula (4), G and B are n × n order matrixes respectively, wherein G is a real part of an admittance matrix, and B is an imaginary part of the admittance matrix, and are constants; in the power flow calculation, an active power injection P and a reactive power injection Q are both nodes with given quantities, called PQ nodes, and the active power injection P and the node voltage amplitude V of the nodes are both nodes with given quantities, called PV nodes;
since the mapping from the V- θ space to the P-Q space is many-to-one, the power system operates near a point (V1, θ 0), and there is a one-to-one mapping relationship from the V- θ space to the P-Q space in a small neighborhood of the operating point, equation (4) is transformed into a matrix form as follows:
Figure BDA0001266742260000061
in formula (5), the PV junction and PQ junction are separated, A, B, C, D, E, F, G, H and I are block matrices with the order of n × n, n × n (n-g), n × g, (n-g) × n, (n-g) x (n-g), (n-g) x g, g × n (n-g), g × g, respectively;
the following equation (5) yields:
△VG＝G·△P+H·△QL+I·△QG(6)
△VL＝D·△P+E·△QL+F·△QG(7)
the following equation (6) yields:
△QG＝I-1·△VG-I-1·G·△P-I-1·H·△QL(8)
bringing formula (7) into formula (8) to obtain:
△VL＝(D-F·I-1·G)·△P+(E-F·I-1·H)·△QL+F·I-1·△VG(9)
is provided with
Figure BDA0001266742260000062
Is the upper voltage amplitude limit of the load node i,
Figure BDA0001266742260000063
is the present voltage of the load node i, P0，Q0And VG 0Respectively representing the values of corresponding quantities under the current operating condition, and the row vector s is represented by a matrix (D-F.I) of the voltage amplitude of the node I in the formula (9)-1·G)、(E-F·I-1H) and F.I-1The corresponding row vector in (1); then there are:
Figure BDA0001266742260000064
the final finish of formula (10) is:
Figure BDA0001266742260000065
in the formula (11), α, β and λ are all static security domain boundary coefficients;
thus, the static security domain of the upper voltage limit of the load node i is defined as:
Figure BDA0001266742260000066
similarly, the static security domain of the lower voltage limit of the load node i:
Figure BDA0001266742260000067
the static voltage security domain of the whole power system is the intersection of the static voltage security domains that the voltage upper and lower limit constraints of all the nodes are satisfied, namely:
Figure BDA0001266742260000071
and determining a control parameter space of the system according to the current power system element model parameters and the network topology data, and solving a corresponding static voltage safety domain coefficient of the system in a certain operation mode, wherein part of boundary data information is shown in table 2. To facilitate the presentation of the results, the SVSR over the 2-dimensional space, i.e., the cross section of the SVSR over a specific 2-dimensional space, is chosen, as shown in fig. 3. And selecting a two-dimensional cross-sectional view of the security domain boundary corresponding to the load node 9 on P11 and Q11.
Step three, according to the static voltage security domain obtained in the step two, stability margin analysis is carried out on the power system, namely, the security domain boundary coefficient obtained in the step two is used, and then the node stability margin is calculated according to the formula (15):
Figure BDA0001266742260000072
in the formula (15), srmjThe numerical value is positive to indicate that the current power system is safe, and the larger the numerical value is, the larger the numerical value isThe larger the stability margin of the operation mode of the front power system is, the larger the node j belongs to a load node;
finding a boundary with the minimum stability margin in the current operation mode of the power system, wherein the stability margin value of the power system is the minimum margin value corresponding to all the boundaries; the stability margin value SRM calculation formula of the power system is as follows:
SRM＝min(srmj)(j∈L) (16)。
the operation mode of the actual power system can be changed due to overhaul and extension of the power system, different orders and different time periods in a day. To facilitate the presentation of the results, different load levels were chosen for the analysis, the analysis results are shown in table 1. As can be seen from the analysis of table 1, an increase in the system load decreases the stability margin of the system. The reduction of the stability margin of the system after the load is increased is small due to the sufficient installed capacity 9966.2MW reserve of the system. The current operating point is shortest from the security domain boundary of the load node BUS 9.
TABLE 1
Current quantity After increasing
Total load of system (MW) 4242.0 4666.2
Margin of stability 0.047 0.0466
Margin value corresponding load node compilationNumber (C) BUS 9 BUS 9
Determining an optimal index of a substation (OISA) according to the obtained static security domain boundary coefficients alpha and beta, wherein the optimal index of the substation refers to: the sum of the absolute value of the product of the active value and the coefficient corresponding to the active parameter and the absolute value of the product of the reactive value and the coefficient corresponding to the reactive parameter is as follows:
OISA＝|αiPi|+|βiQi|(i∈L) (17)
and sequencing the preferred indexes of the input transformer substations, taking out N nodes with large preferred index values of the input transformer substations as the preferred access points of the transformer substations, wherein the value of N is 2-10, namely 2 transformer substation access schemes are selected, namely scheme 1 and scheme 2.
And step four, setting the original network structure of the power system as a scene A, and on the basis of the original network structure of the power system, switching the priority access point of the substation determined in the step three into the newly-added substation to obtain a scene B, and converting the PQ node at the access point into a PV node.
And step three, the distance between the current operation mode and the boundary corresponding to the BUS 9 is shortest. From the aspect of improving the static voltage safety level of a system when the transformer substation is put into use, the coefficient corresponding to the BUS 9 boundary is analyzed, and part of data is shown in a table 2. Sorting OISA, and taking a node with a large OISA value as a substation priority access point; from table 2 it may be prioritized to invest in substations at node 11 and node 13. Scheme 1: the transformer substation is put into the load node 11; scheme 2: the substation is launched at the load node 13.
TABLE 2
Figure BDA0001266742260000081
And fifthly, under the condition that the parameters of the transformer substations which are put into the transformer substations are consistent, constructing a security domain of the power system corresponding to the N transformer substation access schemes of the scene B by using the method provided by the step two, comparing the stability margin values of the power systems of the N transformer substation access schemes and the power system of the scene A through stability margin analysis, and finally determining the scheme as the transformer substation access scheme if the power system with the maximum stability margin value is one of the transformer substation access schemes in the scene B, otherwise, not considering the transformer substations accessed in the power system.
In this embodiment, the pair of system stability margins corresponding to the scheme 1 and the scheme 2 and the power system not accessed to the substation is shown in fig. 4. From the analysis of table 1, the stability margins of the access substation systems on BUS 11 and BUS 13 are improved. Compared with the BUS 11, the margin improvement amplitude is larger after the transformer substation is accessed. Therefore, the scheme of accessing the transformer substation to the BUS 11 is more reasonable.
While the present invention has been described with reference to the accompanying drawings, the present invention is not limited to the above-described embodiments, which are illustrative only and not restrictive, and various modifications which do not depart from the spirit of the present invention and which are intended to be covered by the claims of the present invention may be made by those skilled in the art.

Claims (4)

1. A transformer substation access scheme auxiliary evaluation method based on a security domain is characterized by comprising the following steps:
step one, obtaining state information under a current operation mode through load flow calculation according to power system data, wherein the state information comprises a node voltage amplitude V and a node voltage phase angle theta, and generating an admittance matrix under a current network structure;
step two, obtaining a matrix expression form of a node injection equation by using the admittance matrix obtained in the step one, and determining a decision parameter space by a control variable of the power system so as to construct a corresponding static voltage security domain boundary;
step three, calculating a stability margin value of the power system according to the static voltage security domain obtained in the step two; finding a boundary with the minimum stability margin in the current operation mode of the power system, acquiring parameter information corresponding to the boundary, and determining an optimal selection index of an input substation, wherein the optimal selection index of the input substation is as follows: the sum of the absolute value of the product of the coefficient and the active value corresponding to the active parameter and the absolute value of the product of the coefficient and the reactive value corresponding to the reactive parameter; sequencing the preferred indexes of the input transformer substations, and taking N nodes with large preferred index values of the input transformer substations as the preferred access points of the transformer substations, wherein the value of N is 2-10;
setting the original network structure of the power system as a scene A, and on the basis of the original network structure of the power system, accessing the newly-added transformer substation according to the priority access point of the transformer substation determined in the step three, wherein the network structure of the power system is a scene B, and converting the PQ node at the access point into a PV node;
and fifthly, under the condition that the parameters of the transformer substations which are put into the transformer substations are consistent, constructing a security domain of the power system corresponding to the N transformer substation access schemes of the scene B by using the method provided by the step two, comparing the stability margin values of the power systems of the N transformer substation access schemes and the power system of the scene A through stability margin analysis, and finally determining the scheme as the transformer substation access scheme if the power system with the maximum stability margin value is one of the transformer substation access schemes in the scene B, otherwise, not considering the transformer substations accessed in the power system.
2. The transformer substation access scheme auxiliary evaluation method based on the security domain according to claim 1, wherein the static voltage security domain construction method in the second step specifically comprises:
setting: the power system is provided with n-1 nodes and nb branches, wherein the node 0 is a loose node and is provided with g +1 generator nodes; representing a set of generator nodes and substation nodes except for a relaxation node by S; representing a set of load nodes by L;
in a small neighborhood of the power system operating point V equal to 1 and θ equal to 0, cos θ is usedij＝1,sinθij＝θi-θjProcessing an alternating current equation to obtain a formula (2), wherein the alternating current equation is shown as a formula (1):
Figure FDA0002565341500000011
in the formula (1), Pij、QijActive and reactive power transmitted for line ij; vi、VjThe voltage amplitudes of the nodes i and j are respectively; thetai、θjThe phase angles of the voltages, θ, at nodes i, j, respectivelyij＝θi-θj；Gij、BijIs the corresponding element of the admittance matrix;
Figure FDA0002565341500000012
applying kirchhoff's theorem to the node i to obtain:
Figure FDA0002565341500000021
in the formula (3), Pi、QiActive power injection and reactive power injection for a node i; writing equation (3) in matrix form:
Figure FDA0002565341500000022
in the formula (4), G and B are n × n order matrixes respectively, wherein G is a real part of an admittance matrix, and B is an imaginary part of the admittance matrix, and are constants; in the power flow calculation, an active power injection P and a reactive power injection Q are both nodes with given quantities, called PQ nodes, and the active power injection P and the node voltage amplitude V of the nodes are both nodes with given quantities, called PV nodes;
since the mapping from the V- θ space to the P-Q space is many-to-one, the power system operates near a point (V1, θ 0), and there is a one-to-one mapping relationship from the V- θ space to the P-Q space in a small neighborhood of the operating point, equation (4) is transformed into a matrix form as follows:
Figure FDA0002565341500000023
in formula (5), the PV node and PQ node are separated, A, B, C, D, E, F, G, H and I are block matrixes with the order of n × n, n × n (n-g), n × g, (n-g) × n, (n-g) x (n-g), (n-g) x g, g × n (n-g), g × g, respectively;
the following equation (5) yields:
ΔVG＝G·ΔP+H·ΔQL+I·ΔQG(6)
ΔVL＝D·ΔP+E·ΔQL+F·ΔQG(7)
the following equation (6) yields:
ΔQG＝I-1·ΔVG-I-1·G·ΔP-I-1·H·ΔQL(8)
bringing formula (7) into formula (8) to obtain:
ΔVL＝(D-F·I-1·G)·ΔP+(E-F·I-1·H)·ΔQL+F·I-1·ΔVG(9)
is provided with
Figure FDA0002565341500000024
Is the upper voltage amplitude limit of the load node i,
Figure FDA0002565341500000025
is the present voltage of the load node i, P0，Q0And VG 0Respectively representing the values of corresponding quantities under the current operating condition, and the row vector s is represented by a matrix (D-F.I) of the voltage amplitude of the node I in the formula (9)-1·G)、(E-F·I-1H) and F.I-1The corresponding row vector in (1); then there are:
Figure FDA0002565341500000026
the final finish of formula (10) is:
Figure FDA0002565341500000031
in the formula (11), α, β and λ are all static security domain boundary coefficients;
thus, the static security domain of the upper voltage limit of the load node i is defined as:
Figure FDA0002565341500000032
similarly, the static security domain of the lower voltage limit of the load node i:
Figure FDA0002565341500000033
the static voltage security domain of the whole power system is the intersection of the static voltage security domains that the voltage upper and lower limit constraints of all the nodes are satisfied, namely:
Figure FDA0002565341500000034
3. the security domain-based substation access scheme auxiliary evaluation method according to claim 2, wherein in step three, the calculation method of the power system stability margin value is:
and C, calculating the node stability margin according to the security domain boundary coefficient obtained in the step II as follows:
Figure FDA0002565341500000035
in the formula (15), j ∈ L, srmjIf the numerical value is positive, the current power system is safe, if the numerical value is larger, the stability margin of the current power system operation mode is larger, and the node j belongs to a load node;
the stability margin value of the power system is the minimum margin value corresponding to all boundaries; the stability margin value SRM calculation formula of the power system is as follows:
SRM＝min(srmj)，j∈L (16)。
4. the security domain-based substation access scheme auxiliary evaluation method according to claim 2, wherein in step three, the calculation formula of the preferred index of the transformer substation is as follows:
OISA＝|αiPi|+|βiQi|，i∈L (17)。
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* Cited by examiner, † Cited by third party
Title
"A Method of Auxiliary Planning for Intelligent Substation Access System Based on Security Region";Gao Yi等;《Energy and Power Engineering》;20170406;第675-682页 *
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