A method and system for ranking self-transient voltage stability support capability of a generator set

Abstract

The present application relates to a kind of generator set self transient voltage stability support ability sequencing method and system, method includes: the simulation model of evaluating the self transient voltage stability support ability of generator set is constructed;The reactive power curve of each generator set during fault is calculated by simulation model;The transient voltage stability support ability sequencing index of each generator set is calculated by reactive power curve;According to the size of transient voltage stability support ability sequencing index, the self transient voltage stability support ability of all generator set is sequenced.Constructed simulation model can exclude the influence of external network frame factor, realize the quantitative analysis of the self transient voltage stability support ability of unit, provide convenience for power grid operation mode arrangement.

Description

Technical Field

[0001] This invention belongs to the field of power system safety and stability control technology, and in particular relates to a method and system for ranking the transient voltage stability support capability of generator sets. Background Technology

[0002] The transient voltage stability of a power grid affects its power supply capacity and its ability to absorb clean energy. Maintaining a certain operating mode is an important means of ensuring the transient voltage stability level of the power grid. The transient voltage stability support capability of the generating unit itself is an important factor affecting the overall transient voltage stability level of the system. Different parameters of the generating unit and different response characteristics of the control system will affect the transient voltage stability support capability of the generating unit.

[0003] To ensure the safety of power grid operation, it is necessary to carefully analyze the transient voltage stability support capability of each generating unit in the grid and select appropriate generating units to start based on their transient voltage stability support capability. The transient voltage stability response characteristics of a generator are closely related to the voltage felt at the generator terminals. However, due to the different connection locations of generators in the system, the terminal voltages of different generators are different during actual system operation, making it impossible to directly compare the transient voltage stability response characteristics of the generators themselves. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a method and system for ranking the transient voltage stability support capabilities of generator sets.

[0005] The technical solution adopted in this invention is:

[0006] Firstly, a method for ranking the transient voltage stability support capabilities of generator sets is provided, including:

[0007] Construct a simulation model to evaluate the transient voltage stability support capability of the generator set itself;

[0008] The reactive power curve of each generator set during a fault is calculated using a simulation model.

[0009] The transient voltage stability support capability ranking index of each generator set is calculated by the reactive power curve.

[0010] The transient voltage stability support capabilities of all generator sets are ranked according to the magnitude of the transient voltage stability support capability ranking index.

[0011] Furthermore, the structure of the simulation model includes:

[0012] N generator sets;

[0013] N generator sets are simultaneously connected to the first common busbar;

[0014] The first common busbar is connected to the second common busbar via a transmission line;

[0015] The second common busbar is connected to an infinite power equivalent machine, which has zero resistance and a constant voltage.

[0016] Furthermore, the reactive power curve of each generator set during the fault period is calculated using a simulation model, including;

[0017] A three-phase short-circuit fault is simulated using a simulation model. The three-phase short-circuit fault is a transient metallic ground fault occurring on the transmission line between the first and second common busbars, near the second common busbar. The duration of the three-phase short-circuit fault is... ;

[0018] Calculate generator set i during fault duration reactive power curve within .

[0019] Furthermore, the transient voltage stability support capability ranking index for each generator set is calculated using the reactive power curve, including:

[0020] Through the reactive power curve of generator set i Calculate the reactive power integral value and use it as a ranking index for transient voltage stability support capability.

[0021] The formula for calculating the reactive power integral value is:

[0022] ;

[0023] in, Indicates the start time of a three-phase short-circuit fault; Let be the reactive power value of generator set i at time t;

[0024] or,

[0025] Through the reactive power curve of generator set i Calculate the average reactive power and use it as a ranking index for transient voltage stability support capability.

[0026] The formula for calculating the average reactive power is:

[0027] .

[0028] Furthermore, the transient voltage stability support capabilities of all generator units are ranked according to the magnitude of the transient voltage stability support capability ranking index, including:

[0029] Based on the transient voltage stability support capability ranking index of all generator sets, they are sorted from largest to smallest to obtain an initial ranking table of the transient voltage stability support capability of all generator sets.

[0030] By combining the capacity information of each generator unit with the ranking index of transient voltage stability support capability, the initial ranking table is corrected to obtain the corrected ranking table.

[0031] Secondly, a ranking system for the transient voltage stability support capability of a generator set is provided, including:

[0032] The simulation model building module is used to build a simulation model to evaluate the transient voltage stability support capability of the generator set itself.

[0033] The reactive power curve calculation module is used to calculate the reactive power curve of each generator set during a fault using a simulation model.

[0034] The index calculation module is used to calculate the ranking index of transient voltage stability support capability of each generator set through reactive power curve.

[0035] The sorting module is used to sort the transient voltage stability support capabilities of all generator sets according to the size of the transient voltage stability support capability sorting index.

[0036] Furthermore, the structure of the simulation model includes:

[0037] N generator sets;

[0038] N generator sets are simultaneously connected to the first common busbar;

[0039] The first common busbar is connected to the second common busbar via a transmission line;

[0040] The second common busbar is connected to an infinite power equivalent machine, which has zero resistance and a constant voltage.

[0041] Furthermore, the reactive power curve calculation module is specifically used to simulate a three-phase short-circuit fault through a simulation model. The three-phase short-circuit fault is a transient three-phase metallic ground fault occurring on the transmission line between the first and second common busbars, near the second common busbar. The duration of the three-phase short-circuit fault is... ; Calculate the duration of the fault for generator set i reactive power curve within .

[0042] Furthermore, the index calculation module is specifically used to calculate the reactive power curve of generator set i. Calculate the reactive power integral value and use it as a ranking index for transient voltage stability support capability.

[0043] The formula for calculating the reactive power integral value is:

[0044] ;

[0045] in, Indicates the start time of a three-phase short-circuit fault; Let be the reactive power value of generator set i at time t;

[0046] or,

[0047] Through the reactive power curve of generator set i Calculate the average reactive power and use it as a ranking index for transient voltage stability support capability.

[0048] The formula for calculating the average reactive power is:

[0049] .

[0050] Furthermore, the sorting module is specifically used to sort all generator sets according to the transient voltage stability support capability sorting index from largest to smallest, to obtain an initial sorting table of the transient voltage stability support capability of each generator set; and to sort and correct the initial sorting table by combining the capacity information of each generator set with the transient voltage stability support capability sorting index, to obtain a corrected sorting table.

[0051] The beneficial effects achieved by this invention are as follows:

[0052] A simulation model is constructed to evaluate the transient voltage stability support capability of generator units. The reactive power curve of each generator unit during a fault is calculated using the simulation model. A ranking index for the transient voltage stability support capability of each generator unit is calculated based on the reactive power curve. The transient voltage stability support capability of all generator units is ranked according to the magnitude of the ranking index. The constructed simulation model can eliminate the influence of external grid factors, enabling quantitative analysis of the unit's own transient voltage stability support capability and providing convenience for grid operation mode planning. Attached Figure Description

[0053] Figure 1 This is a flowchart of the method for ranking the transient voltage stability support capability of generator sets according to the present invention;

[0054] Figure 2 This is a structural diagram of the simulation model of the present invention;

[0055] Figure 3 This is a structural diagram of the simulation model of the eight generator sets of this invention;

[0056] Figure 4 The reactive power curves of each generator set in this invention are shown below.

[0057] Figure 5 This is a structural diagram of the generator set's own transient voltage stability support capability ranking system according to the present invention. Detailed Implementation

[0058] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0059] like Figure 1 As shown, this embodiment of the invention provides a method for ranking the transient voltage stability support capability of a generator set, including:

[0060] 101. Construct a simulation model to evaluate the transient voltage stability support capability of the generator set itself;

[0061] In this embodiment, the specific structural diagram of the simulation model is as follows: Figure 2 As shown, there are N generator sets;

[0062] N generator sets are simultaneously connected to the first common busbar (common busbar 1); the first common busbar (common busbar 1) is connected to the second common busbar (common busbar 2) through a transmission line; the second common busbar (common busbar 2) is connected to an infinite power equivalent machine, the infinite power equivalent machine has zero resistance and constant voltage.

[0063] 102. The reactive power curve of each generator set during a fault is calculated using a simulation model;

[0064] In this embodiment, taking 8 generator sets as an example, the simulation model is as follows: Figure 3 As shown, a three-phase short-circuit fault is applied near the common busbar 2. The three-phase short-circuit fault is a three-phase metallic grounding transient short-circuit fault on the transmission line between common busbar 1 and common busbar 2, near the side of common busbar 2. The duration of the three-phase short-circuit fault is... ;

[0065] At this point, for the eight generator sets under consideration, during the duration of the fault... Since the infinite power equivalent generators all provide constant voltage, the terminal voltages experienced by the eight generator sets are consistent, allowing for accurate analysis of the transient voltage stability characteristics of each generator set. Specifically, after applying a three-phase short-circuit fault lasting 0.2 seconds near the common busbar 2, the reactive power curves of each generator set are as follows: Figure 4 As shown.

[0066] from Figure 4As can be seen, the reactive power response characteristics of Unit 1 and Unit 2 during their own faults are the strongest, while the reactive power response characteristics of Unit 3, Unit 4 and Unit 8 are basically the same, which is worse than that of Unit 1 and Unit 2. The reactive power response characteristics of Unit 6 are even worse, and the worst are Unit 5 and Unit 7.

[0067] 103. Rank the transient voltage stability support capability of each generator set by calculating the reactive power curve;

[0068] In this embodiment, the ranking index of transient voltage stability support capability can be calculated in two ways: by calculating the integral value of reactive power and the average value of reactive power.

[0069] Through the reactive power curve of generator set i Calculate the reactive power integral value and use it as a ranking index for transient voltage stability support capability.

[0070] The formula for calculating the reactive power integral value is:

[0071] ;

[0072] in, Indicates the start time of a three-phase short-circuit fault; Let be the reactive power value of generator set i at time t;

[0073] or,

[0074] Through the reactive power curve of generator set i Calculate the average reactive power and use it as a ranking index for transient voltage stability support capability.

[0075] The formula for calculating the average reactive power is:

[0076] .

[0077] 104. The transient voltage stability support capabilities of all generator sets are ranked according to the magnitude of the transient voltage stability support capability ranking index.

[0078] In this embodiment, through Figure 4 The reactive power curves of each generator set are shown to calculate the average reactive power. The average reactive power and capacity of each generator set are displayed in Table 1 below.

[0079]

[0080] First, all generator sets are sorted according to the transient voltage stability support capability ranking index from largest to smallest to obtain an initial ranking table of the transient voltage stability support capability of each generator set.

[0081] Secondly, based on the capacity of each unit in Table 1 above, it can be seen that the reactive power response characteristics of units 5 and 7 are quite similar. Because their own capacity is small, their reactive power output is small during the fault duration. The capacity of the units also affects the ranking result. The reactive power response characteristics of units 3, 4, and 8, which have similar capacities, are basically similar, and their performance is better than that of unit 6. Combining the capacity information of each generator unit with the ranking index of transient voltage stability support capability, the initial ranking table is corrected to obtain the corrected ranking table.

[0082] The beneficial effects achieved by the embodiments of the present invention are as follows:

[0083] A simulation model is constructed to evaluate the transient voltage stability support capability of generator units. The reactive power curve of each generator unit during a fault is calculated using the simulation model. A ranking index for the transient voltage stability support capability of each generator unit is calculated based on the reactive power curve. The transient voltage stability support capability of all generator units is ranked according to the magnitude of the ranking index. The constructed simulation model can eliminate the influence of external grid factors, enabling quantitative analysis of the unit's own transient voltage stability support capability and providing convenience for grid operation mode planning.

[0084] Based on the generator set's own transient voltage stability support capability ranking method described in the above embodiments, the generator set's own transient voltage stability support capability ranking system will be explained below through embodiments.

[0085] like Figure 5 As shown, this embodiment of the invention provides a generator set's own transient voltage stability support capability ranking system, including:

[0086] The simulation model building module 501 is used to build a simulation model to evaluate the transient voltage stability support capability of the generator set itself.

[0087] The reactive power curve calculation module 502 is used to calculate the reactive power curve of each generator set during a fault using a simulation model.

[0088] The index calculation module 503 is used to calculate the ranking index of transient voltage stability support capability of each generator set through the reactive power curve.

[0089] The sorting module 504 is used to sort the transient voltage stability support capabilities of all generator sets according to the size of the transient voltage stability support capability sorting index.

[0090] Preferably, the structure of the simulation model includes:

[0091] N generator sets;

[0092] N generator sets are simultaneously connected to the first common busbar;

[0093] The first common busbar is connected to the second common busbar via a transmission line;

[0094] The second common busbar is connected to an infinite power equivalent machine, which has zero resistance and a constant voltage.

[0095] Preferably, the reactive power curve calculation module 502 is specifically used to set a three-phase short-circuit fault through a simulation model. The three-phase short-circuit fault is a three-phase metallic grounding transient short-circuit fault on the transmission line between the first and second common busbars, closer to the second common busbar. The duration of the three-phase short-circuit fault is... ; Calculate the duration of the fault for generator set i reactive power curve within .

[0096] Preferably, the index calculation module 503 is specifically used to calculate the reactive power curve of generator set i. Calculate the reactive power integral value and use it as a ranking index for transient voltage stability support capability.

[0097] The formula for calculating the reactive power integral value is:

[0098] ;

[0099] in, Indicates the start time of a three-phase short-circuit fault; Let be the reactive power value of generator set i at time t;

[0100] or,

[0101] Through the reactive power curve of generator set i Calculate the average reactive power and use it as a ranking index for transient voltage stability support capability.

[0102] The formula for calculating the average reactive power is:

[0103] .

[0104] Preferably, the sorting module 504 is specifically used to sort all generator sets according to the transient voltage stability support capability sorting index in descending order to obtain an initial sorting table of the transient voltage stability support capability of all generator sets; and to sort and correct the initial sorting table by combining the capacity information of each generator set with the transient voltage stability support capability sorting index to obtain a corrected sorting table.

[0105] The beneficial effects achieved by the embodiments of the present invention are as follows:

[0106] The simulation model construction module 501 constructs a simulation model to evaluate the transient voltage stability support capability of the generator sets themselves; the reactive power curve calculation module 502 calculates the reactive power curve of each generator set during a fault using the simulation model; the index calculation module 503 calculates the ranking index of the transient voltage stability support capability of each generator set using the reactive power curve; and the ranking module 504 ranks all generator sets according to the magnitude of the ranking index. The constructed simulation model can eliminate the influence of external grid factors, realize the quantitative analysis of the transient voltage stability support capability of the generator sets themselves, and provide convenience for the arrangement of grid operation modes.

[0107] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can 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, etc.) containing computer-usable program code.

[0108] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can 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, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0109] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0110] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0111] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of the claims of the present invention pending approval.

Claims

1. A method for ranking the transient voltage stability support capability of a generator set, characterized in that, include: Construct a simulation model to evaluate the transient voltage stability support capability of the generator set itself; The reactive power curve of each generator set during a fault is calculated using a simulation model. The transient voltage stability support capability ranking index of each generator set is calculated by the reactive power curve. The transient voltage stability support capabilities of all generator sets are ranked according to the magnitude of the transient voltage stability support capability ranking index.

2. The method for ranking the transient voltage stability support capability of a generator set according to claim 1, characterized in that, The structure of the simulation model includes: N generator sets; N generator sets are simultaneously connected to the first common busbar; The first common busbar is connected to the second common busbar via a transmission line; The second common busbar is connected to an infinite power equivalent machine, which has zero resistance and a constant voltage.

3. The method for ranking the transient voltage stability support capability of a generator set according to claim 2, characterized in that, The calculation of the reactive power curve of each generator set during a fault using a simulation model includes: A three-phase short-circuit fault is simulated using a simulation model. The three-phase short-circuit fault is a transient metallic ground fault occurring on the transmission line between the first and second common busbars, near the second common busbar. The duration of the three-phase short-circuit fault is... ; Calculate generator set i during fault duration reactive power curve within .

4. The method for ranking the transient voltage stability support capability of a generator set according to claim 3, characterized in that, The ranking index for the transient voltage stability support capability of each generator set, calculated using the reactive power curve, includes: Through the reactive power curve of generator set i Calculate the reactive power integral value and use it as a ranking index for transient voltage stability support capability. The formula for calculating the reactive power integral value is: ； in, Indicates the start time of a three-phase short-circuit fault; Let be the reactive power value of generator set i at time t; or, Through the reactive power curve of generator set i Calculate the average reactive power and use it as a ranking index for transient voltage stability support capability. The formula for calculating the average reactive power is: 。 5. The method for ranking the transient voltage stability support capability of a generator set according to claim 1, characterized in that, The ranking of the transient voltage stability support capabilities of all generator sets based on the magnitude of the transient voltage stability support capability ranking index includes: Based on the transient voltage stability support capability ranking index of all generator sets, they are sorted from largest to smallest to obtain an initial ranking table of the transient voltage stability support capability of all generator sets. By combining the capacity information of each generator unit with the ranking index of transient voltage stability support capability, the initial ranking table is corrected to obtain the corrected ranking table.

6. A ranking system for the transient voltage stability support capability of a generator set, characterized in that, include: The simulation model building module is used to build a simulation model to evaluate the transient voltage stability support capability of the generator set itself. The reactive power curve calculation module is used to calculate the reactive power curve of each generator set during a fault using a simulation model. The index calculation module is used to calculate the ranking index of transient voltage stability support capability of each generator set through reactive power curve. The sorting module is used to sort the transient voltage stability support capabilities of all generator sets according to the size of the transient voltage stability support capability sorting index.

7. The generator set's own transient voltage stability support capability ranking system according to claim 6, characterized in that, The structure of the simulation model includes: N generator sets; N generator sets are simultaneously connected to the first common busbar; The first common busbar is connected to the second common busbar via a transmission line; The second common busbar is connected to an infinite power equivalent machine, which has zero resistance and a constant voltage.

8. The generator set's own transient voltage stability support capability ranking system according to claim 7, characterized in that, The reactive power curve calculation module is specifically used to simulate a three-phase short-circuit fault using a simulation model. The three-phase short-circuit fault is a transient three-phase metallic ground fault occurring on the transmission line between the first and second common busbars, near the second common busbar. The duration of the three-phase short-circuit fault is... ; Calculate generator set i during fault duration reactive power curve within .

9. The generator set's own transient voltage stability support capability ranking system according to claim 8, characterized in that, The index calculation module is specifically used to calculate the reactive power curve of generator set i. Calculate the reactive power integral value and use it as a ranking index for transient voltage stability support capability. The formula for calculating the reactive power integral value is: ； in, Indicates the start time of a three-phase short-circuit fault; Let be the reactive power value of generator set i at time t; or, Through the reactive power curve of generator set i Calculate the average reactive power and use it as a ranking index for transient voltage stability support capability. The formula for calculating the average reactive power is: 。 10. The generator set's own transient voltage stability support capability ranking system according to claim 6, characterized in that, The sorting module is specifically used to sort all generator sets according to the transient voltage stability support capability sorting index from largest to smallest, to obtain an initial sorting table of the transient voltage stability support capability of each generator set; and to sort and correct the initial sorting table by combining the capacity information of each generator set with the transient voltage stability support capability sorting index, to obtain a corrected sorting table.

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