Power grid transient voltage stability contribution degree analysis method and device based on effective reactive response time period identification, and storage medium

Abstract

The invention discloses a power grid transient voltage stability contribution degree analysis method based on effective reactive response time period identification, and belongs to the technical field of power system stability analysis. The method comprises the steps of generating a power grid bus transient voltage simulation curve corresponding to each anticipated fault based on power grid operation mode data and an anticipated fault set, and obtaining a weak bus under each anticipated fault by calculating the transient voltage stability margin of the bus after the anticipated fault occurs; according to the change of the transient voltage of the bus after the anticipated fault occurs, the dynamic reactive power effective time period of the weak bus is identified, and the reactive power accumulated electric energy and the reactive power voltage sensitivity of each dynamic reactive power compensation device and the new energy unit to the weak bus in the dynamic reactive power effective time period are obtained; and further determining the transient voltage stability contribution degree of each dynamic reactive power compensation device and the new energy unit to the weak bus. According to the method, the contribution of various reactive power resources in the system to maintaining the stability of the transient voltage can be efficiently analyzed according to the dynamic characteristics of the transient voltage under the anticipated fault.

Description

A method, device, and storage medium for analyzing the contribution of power grid transient voltage stability based on effective reactive power response period identification. Technical Field

[0001] This invention belongs to the field of power system stability analysis technology, specifically relating to a method, device, and storage medium for analyzing the contribution of power grid transient voltage stability based on effective reactive power response period identification. Background Technology

[0002] With the construction of new power systems, the grid-connected capacity of new energy units is constantly increasing, and a large number of conventional units are being replaced, resulting in a significant decrease in the reactive power and voltage support capacity of the power grid. Severe AC / DC faults may lead to transient voltage instability.

[0003] Some dynamic reactive power compensation devices or new energy units in the power grid have high reactive voltage sensitivity to weak busbars, but the effective reactive power generated after a fault is small. Therefore, a single reactive voltage sensitivity evaluation method is insufficient to accurately characterize the reactive power contribution capability of equipment and units.

[0004] Patent application CN110601196A proposes "a method for identifying weak areas of voltage stability based on reactive power-voltage sensitivity matrix". It identifies weak areas of static voltage by calculating the sensitivity matrix under steady-state operation point. This method can effectively reflect the static voltage characteristics under normal operation mode, but it fails to effectively take into account the response of dynamic components of the system after large disturbances. Therefore, it is difficult to accurately characterize the real-time voltage support capability and weak links of the system in transient processes.

[0005] Patent CN113131441B proposes "a transient voltage stability discrimination and control method based on local measurement". It uses the local voltage trajectory information of the bus to quickly determine the stability and start local reactive power support. The method has a fast response and does not require wide area communication. However, its sensitivity concept is limited to the static relationship between the local voltage of a single bus and the local reactive power injection. It still cannot accurately reflect the contribution of various reactive resources in the system to maintaining transient voltage stability and cannot meet the reactive power optimization needs of high-proportion new energy power systems. Summary of the Invention

[0006] The purpose of this invention is to provide a method, device, and storage medium for analyzing the contribution of power grid transient voltage stability based on the identification of effective reactive power response periods. This method can accurately analyze the contribution of various reactive resources in the system to maintaining transient voltage stability based on the dynamic characteristics of the transient voltage simulation curve under anticipated disturbances, providing key characteristic indicators for the construction of a new power system's safe and stable domain. The technical solution adopted in this invention is as follows.

[0007] On the one hand, the present invention provides a method for analyzing the contribution of transient voltage stability in a power grid, comprising:

[0008] Acquire power grid operation mode data and expected fault set data, and generate power grid bus transient voltage simulation curves corresponding to each expected fault based on the acquired data;

[0009] Based on the transient voltage simulation curve of the power grid bus, the weak bus under each anticipated fault is obtained by calculating the transient voltage stability margin of each bus after the occurrence of the anticipated fault.

[0010] Based on the dynamic changes in the transient voltage of the bus after the anticipated fault occurs, the effective period of dynamic reactive power of the weak bus is identified.

[0011] Based on the simulation curve of the transient voltage of the power grid bus, calculate the cumulative reactive power of each dynamic reactive power compensation device and new energy unit on the weak bus during the effective period of dynamic reactive power;

[0012] Obtain the reactive voltage sensitivity of each dynamic reactive power compensation device and new energy unit to the weak bus; determine the contribution of each dynamic reactive power compensation device and new energy unit to the transient voltage stability of the weak bus based on the accumulated reactive power and reactive voltage sensitivity.

[0013] Optionally, based on the accumulated reactive power and reactive voltage sensitivity, the contribution of each dynamic reactive power compensation device and new energy unit to the transient voltage stability of the weak busbar is determined, including:

[0014] Based on the described reactive voltage sensitivity, determine the effective reactive power compensation device and new energy unit;

[0015] Based on the reactive power accumulation and reactive voltage sensitivity of each effective reactive power compensation device and new energy unit to the weak bus, the contribution of each effective reactive power compensation device and new energy unit to the transient voltage stability of the weak bus is determined.

[0016] In the above technical solutions, the contribution analysis identifies the "critical reactive power sources" that play a decisive role in voltage stability through reactive power sensitivity calculation. By focusing solely on these key devices, the risk points of voltage instability can be identified more accurately. When formulating voltage control or reactive power optimization strategies, these devices can be prioritized for configuration or adjustment, avoiding redundant control of a large number of low-impact devices, achieving more efficient voltage support, and reducing the complexity and cost of the control system.

[0017] The calculation of the aforementioned reactive power voltage sensitivity can be performed using existing technologies, such as establishing reactive power voltage sensitivity models for each dynamic reactive power compensation device and new energy unit based on the weak bus, and simulating the bus voltage change caused by the unit reactive power change of each dynamic reactive power compensation device and new energy unit. Specific details will not be elaborated further.

[0018] Optionally, determining effective reactive power compensation devices and new energy generating units based on the reactive power voltage sensitivity includes: designating reactive power compensation devices and new energy generating units with reactive power voltage sensitivity greater than a preset sensitivity threshold as effective reactive power compensation devices and effective new energy generating units.

[0019] Optionally, the step of calculating the transient voltage stability margin of each bus after a anticipated fault occurs to obtain the weak bus under each anticipated fault includes:

[0020] For each anticipated fault in the anticipated fault set, the transient voltage stability margin of each bus after the anticipated fault occurs is calculated based on the transient voltage simulation curve of the corresponding power grid bus. The bus with the lowest transient voltage stability margin is taken as the weak bus under the corresponding anticipated fault.

[0021] Optionally, identifying the effective period of dynamic reactive power of the weak bus based on the dynamic change of the bus transient voltage after the anticipated fault occurs includes:

[0022] The expected time of failure is taken as the starting point of the effective period of dynamic reactive power;

[0023] Based on the simulation curve of the transient voltage of the power grid bus, it is determined whether the transient voltage of the weak bus can recover to the preset reference value after the expected fault occurs, such as 0.8 pu. If the transient voltage of the weak bus can recover to the preset reference value, the moment when the voltage of the weak bus first recovers to the preset voltage threshold after the expected fault occurs is determined as the end point of the effective period of dynamic reactive power.

[0024] If the transient voltage of the weak bus cannot recover to the preset reference value, the end point of the effective period of dynamic reactive power is determined according to the preset transient voltage steady-state criterion.

[0025] Optionally, determining the endpoint of the effective period of dynamic reactive power based on the preset transient voltage steady-state criterion includes: determining whether there are m consecutive weak bus transient voltage sampling points that satisfy the transient voltage steady-state criterion within a preset observation period after the anticipated fault occurs; if so, then the mth sampling point is selected as the endpoint of the effective period of dynamic reactive power. The sampling time corresponding to the transient voltage sampling point of each weak busbar , which serves as the end point of the effective period of dynamic reactive power;

[0026] The transient voltage steady-state criterion is expressed as follows: ,in, Let n be the transient voltage of the weak busbar at sampling point n. Let n be the transient voltage of the weak busbar at the next sampling point. The preset deviation threshold value, This represents the number of consecutive sampling points at which the transient voltage of the weak busbar enters a steady state.

[0027] Optionally, determining the end point of the effective period of dynamic reactive power based on the preset transient voltage steady-state criterion further includes: if, within a preset observation period after the anticipated fault occurs, there are no consecutive m weak bus transient voltage sampling points that satisfy the transient voltage steady-state criterion, then the end time of the preset observation period is taken as the end point of the effective period of dynamic reactive power, expressed as: ,in, This marks the end of the effective period for dynamic reactive power. This marks the starting point of the effective period for dynamic reactive power. The preset observation time is [the time frame].

[0028] The above technical solutions take into account various scenarios of transient voltage changes in the weak bus after a fault occurs, and realize the determination of the end point of the effective period of dynamic reactive power, ensuring its boundedness.

[0029] The dynamic reactive power accumulation calculation is used to quantify the actual support capacity of each dynamic reactive power compensation device and new energy unit for the voltage stability of the weak bus during the effective period of dynamic reactive power. Optionally, based on the transient voltage simulation curve of the power grid bus, the reactive power accumulation of each dynamic reactive power compensation device and new energy unit for the weak bus during the effective period of dynamic reactive power is calculated. The calculation formula is as follows:

[0030]

[0031] In the formula, To be in the dynamic reactive power effective period Inner A dynamic reactive power compensation device or new energy unit for weak busbars Reactive power accumulation , and These represent the start and end points of the effective period for dynamic reactive power, respectively. and They are respectively and Index of the corresponding weak bus transient voltage sampling points; For the first A dynamic reactive power compensation device or new energy unit at a weak busbar The effort wasted wasted. To prevent the failure from occurring A dynamic reactive power compensation device or the steady-state output of a new energy unit.

[0032] Optionally, based on the accumulated reactive power and reactive voltage sensitivity, the contribution of each dynamic reactive power compensation device and new energy unit to the transient voltage stability of the weak bus is determined using the following formula:

[0033]

[0034] In the formula, For the first A dynamic reactive power compensation device or unit for the weak busbar The contribution of transient voltage stability, For the first A dynamic reactive power compensation device or unit for the weak busbar The reactive voltage sensitivity coefficient; For the first A dynamic reactive power compensation device or new energy unit provides power to the weak busbar during the effective period of dynamic reactive power. The reactive power accumulated.

[0035] Optionally, based on the accumulated reactive power and reactive voltage sensitivity, the contribution of each dynamic reactive power compensation device and new energy unit to the transient voltage stability of the weak bus is determined. This further includes: normalizing the calculated transient voltage stability contribution data using the following formula:

[0036]

[0037] In the formula, For the first A dynamic reactive power compensation device or unit for the weak busbar The transient voltage stability normalized contribution, For all dynamic reactive power compensation devices and new energy units to be evaluated, and for weak busbars The total contribution. In the implementation method that only considers key impact equipment, the "all dynamic reactive power compensation devices and new energy units to be evaluated" are also the "effective reactive power compensation devices and new energy units".

[0038] In a second aspect, the present invention provides a power grid transient voltage stability contribution analysis device, comprising:

[0039] The transient voltage simulation module is configured to acquire power grid operation mode data and expected fault set data, and generate transient voltage simulation curves of the power grid bus corresponding to each expected fault based on the acquired data.

[0040] The weak bus analysis module is configured to, based on the transient voltage simulation curve of the power grid bus, calculate the transient voltage stability margin of each bus after the occurrence of a anticipated fault, and obtain the weak bus under each anticipated fault.

[0041] The dynamic reactive power effective period identification module is configured to identify the dynamic reactive power effective period of the weak bus based on the dynamic change of the bus transient voltage after the expected fault occurs.

[0042] The transient voltage simulation analysis module is configured to calculate the cumulative reactive power of each dynamic reactive power compensation device and new energy unit on the weak bus during the effective period of dynamic reactive power, based on the transient voltage simulation curve of the power grid bus.

[0043] The transient voltage stability contribution calculation module is configured to obtain the reactive voltage sensitivity of each dynamic reactive power compensation device and new energy unit to the weak bus; and determine the transient voltage stability contribution of each dynamic reactive power compensation device and new energy unit to the weak bus based on the cumulative reactive power and reactive voltage sensitivity.

[0044] Optionally, the transient voltage stability contribution calculation module determines the transient voltage stability contribution of each dynamic reactive power compensation device and new energy unit to the weak busbar based on the reactive power accumulation and reactive voltage sensitivity, including:

[0045] Based on the described reactive voltage sensitivity, determine the effective reactive power compensation device and new energy unit;

[0046] Based on the reactive power accumulation and reactive voltage sensitivity of each effective reactive power compensation device and new energy unit to the weak bus, the contribution of each effective reactive power compensation device and new energy unit to the transient voltage stability of the weak bus is determined.

[0047] Thirdly, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the power grid transient voltage stability contribution analysis method as described in the first aspect.

[0048] Beneficial effects

[0049] This invention analyzes weak buses through transient simulation and examines the transient voltage characteristics of each weak bus after a fault. This identifies the effective period of dynamic reactive power from the occurrence of a fault to the recovery of the bus voltage. It then accurately calculates the cumulative dynamic reactive energy of each reactive resource during this effective period. Finally, by combining reactive voltage sensitivity and cumulative reactive energy, it calculates the contribution of the power grid to transient voltage stability. This achieves accurate quantification of the supporting capacity of each reactive resource in transient voltage stability, providing a reliable basis for the optimal allocation and stable control of reactive power in new power systems. Attached Figure Description

[0050] Figure 1 shows a flowchart of the power grid transient voltage stability contribution analysis method of the present invention in one embodiment;

[0051] Figure 2 shows a flowchart of another embodiment of the power grid transient voltage stability contribution analysis method of the present invention. Detailed Implementation

[0052] The following description, in conjunction with the accompanying drawings and specific embodiments, provides further details.

[0053] Example 1

[0054] Referring to Figure 1, this embodiment introduces a method for analyzing the contribution of transient voltage stability in a power grid, including:

[0055] Acquire power grid operation mode data and expected fault set data, and generate power grid bus transient voltage simulation curves corresponding to each expected fault based on the acquired data;

[0056] Based on the transient voltage simulation curve of the power grid bus, the weak bus under each anticipated fault is obtained by calculating the transient voltage stability margin of each bus after the occurrence of the anticipated fault.

[0057] Based on the dynamic changes in the transient voltage of the bus after the anticipated fault occurs, the effective period of dynamic reactive power of the weak bus is identified.

[0058] Based on the simulation curve of the transient voltage of the power grid bus, calculate the cumulative reactive power of each dynamic reactive power compensation device and new energy unit on the weak bus during the effective period of dynamic reactive power;

[0059] Obtain the reactive voltage sensitivity of each dynamic reactive power compensation device and new energy unit to the weak bus; determine the contribution of each dynamic reactive power compensation device and new energy unit to the transient voltage stability of the weak bus based on the accumulated reactive power and reactive voltage sensitivity.

[0060] When applied, this embodiment can analyze the contribution of each reactive power resource to the transient voltage stability of the power grid for each anticipated fault, identify the risk points of voltage instability, and use the analysis results as the basis for formulating voltage control or reactive power optimization strategies to achieve efficient voltage support.

[0061] Example 2

[0062] Based on Example 1, this example specifically introduces an implementation method for analyzing the contribution of transient voltage stability in a power grid, which involves the following content.

[0063] I. Simulation of Transient Voltage of Power Grid Bus

[0064] This part can refer to the existing technology of generating the power grid bus transient voltage simulation curve based on power grid operation mode data and expected fault set. The power grid bus transient voltage is simulated for each expected fault to obtain the corresponding simulation curve.

[0065] II. Identifying Weak Busbars Under Anticipated Faults

[0066] In this embodiment, for each anticipated fault in the anticipated fault set, the transient voltage stability margin of each bus after the anticipated fault occurs is calculated based on the transient voltage simulation curve of the corresponding power grid bus. The bus with the lowest transient voltage stability margin is taken as the weak bus under the corresponding anticipated fault.

[0067] III. Identifying the effective period of dynamic reactive power for weak busbars

[0068] In this embodiment, based on the dynamic changes in the transient voltage of the bus after a anticipated fault occurs, the effective period of dynamic reactive power of the weak bus is identified, specifically including:

[0069] S31, the anticipated time of failure As the starting point of the effective period of dynamic reactive power ,Right now ;

[0070] S32, Based on the simulated transient voltage curve of the power grid bus, determine whether the transient voltage of the weak bus can recover to a preset reference value, such as 0.8 pu, after the anticipated fault occurs.

[0071] If the transient voltage of the weak bus can recover to the preset reference value, then the voltage of the weak bus will be restored to the preset voltage threshold for the first time after the anticipated fault occurs. The moment The end point of the effective period of dynamic reactive power is determined. ,Right now It should be noted here that the preset reference value for the transient voltage of the weak bus is not equivalent to the preset voltage threshold. Each can be set based on experience;

[0072] If the transient voltage of the weak bus cannot be restored to the preset reference value, it is necessary to identify the end point of the time period under the unstable or unrecoverable situation. At this time, proceed to step S33 and determine the end point of the effective period of dynamic reactive power according to the preset transient voltage steady-state criterion.

[0073] S33, determine whether there are m consecutive transient voltage sampling points of the weak busbar that satisfy the transient voltage steady-state criterion within a preset observation period after the expected fault occurs:

[0074] If it exists, then the first one... The sampling time corresponding to the transient voltage sampling point of each weak busbar As the end of the effective period of dynamic reactive power ,Right now ;

[0075] Let the transient voltage discrete sampling sequence be... The transient voltage steady-state criterion is expressed as follows: ,in, Let n be the transient voltage of the weak busbar at sampling point n. Let n be the transient voltage of the weak busbar at the next sampling point. The preset deviation threshold value, The number of consecutive sampling points for the transient voltage of the weak bus to enter a steady state;

[0076] If, within a preset observation period following the anticipated fault, there are no consecutive m weak bus transient voltage sampling points that satisfy the transient voltage steady-state criterion, then the end of the preset observation period is taken as the end of the dynamic reactive power effective period, expressed as: ,in, This marks the end of the effective period for dynamic reactive power. This marks the starting point of the effective period for dynamic reactive power. The preset observation time is [the time frame].

[0077] Through the above technical solutions, this embodiment can realize the effective period of dynamic reactive power of the weak bus after the expected fault, especially the effective identification and definition of the end of the period, which lays the foundation for the subsequent accurate quantification of the actual support capacity of each reactive power resource.

[0078] IV. Calculation of Reactive Power Accumulation

[0079] Dynamic reactive power accumulation calculation is used to quantify the actual support capacity of each dynamic reactive power compensation device and new energy unit for the stability of weak bus voltage during the effective period of dynamic reactive power.

[0080] In this embodiment, based on the simulation curve of the transient voltage of the power grid bus, the cumulative reactive power of each dynamic reactive power compensation device and new energy unit on the weak bus during the effective period of dynamic reactive power is calculated, and the formula is:

[0081]

[0082] In the formula, To be in the dynamic reactive power effective period Inner A dynamic reactive power compensation device or new energy unit for weak busbars Reactive power accumulation , and These represent the start and end points of the effective period for dynamic reactive power, respectively. and They are respectively and Index of the corresponding weak bus transient voltage sampling points; For the first A dynamic reactive power compensation device or new energy unit at a weak busbar The effort wasted wasted. To prevent the failure from occurring A dynamic reactive power compensation device or the steady-state output of a new energy unit.

[0083] V. Calculation of Transient Voltage Stability Contribution

[0084] This embodiment first obtains the reactive voltage sensitivity of each dynamic reactive power compensation device and new energy unit to the weak bus, and then determines the contribution of each dynamic reactive power compensation device and new energy unit to the transient voltage stability of the weak bus based on the accumulated reactive power and reactive voltage sensitivity.

[0085] The calculation of reactive voltage sensitivity can be carried out using existing technologies, such as establishing reactive voltage sensitivity models for each dynamic reactive power compensation device and new energy unit based on the weak bus, and simulating the bus voltage change caused by the unit reactive power change of each dynamic reactive power compensation device and new energy unit.

[0086] The contribution of transient voltage stability is calculated using the following formula:

[0087]

[0088] In the formula, For the first A dynamic reactive power compensation device or unit for the weak busbar The contribution of transient voltage stability, For the first A dynamic reactive power compensation device or unit for the weak busbar The reactive voltage sensitivity coefficient; For the first A dynamic reactive power compensation device or new energy unit provides power to the weak busbar during the effective period of dynamic reactive power. The reactive power accumulated.

[0089] To provide a clear comparison of the reactive power support capabilities of all reactive power resources, this embodiment also normalizes the calculated transient voltage stability contribution data using the following formula:

[0090]

[0091] In the formula, For the first A dynamic reactive power compensation device or unit for the weak busbar The transient voltage stability normalized contribution, For all dynamic reactive power compensation devices and new energy units to be evaluated, and for weak busbars Total contribution.

[0092] Example 3

[0093] Based on Example 1, this example introduces another implementation method for analyzing the contribution of power grid transient voltage stability.

[0094] Referring to Figure 2, the simulation of transient voltage at the power grid bus, identification of weak buses under anticipated faults, and calculation of reactive power accumulation in this embodiment can adopt the same implementation method as in Embodiment 2. The difference lies in the calculation of the transient voltage stability contribution:

[0095] First, the reactive voltage sensitivity of each dynamic reactive power compensation device and new energy unit to the weak bus is obtained; then, based on the reactive voltage sensitivity, the effective reactive power compensation devices and new energy units are determined. For example, reactive power compensation devices and new energy units with reactive voltage sensitivity greater than a preset sensitivity threshold are considered as effective reactive power compensation devices and effective new energy units; then, based on the reactive cumulative energy and reactive voltage sensitivity of each effective reactive power compensation device and new energy unit to the weak bus, the transient voltage stability contribution of each effective reactive power compensation device and new energy unit to the weak bus is determined.

[0096] In this implementation, only the "critical reactive power sources" that play a decisive role in voltage stability are identified through reactive power sensitivity calculations. By focusing solely on these key devices, the risk points of voltage instability can be identified more accurately. When formulating voltage control or reactive power optimization strategies, these devices can be prioritized for configuration or adjustment, avoiding redundant control of a large number of low-impact devices, achieving more efficient voltage support, and reducing the complexity and cost of the control system.

[0097] When normalizing the calculated transient voltage stability contribution data in an implementation that only considers critically affected equipment, the formula is... In This can be understood as the first An effective dynamic reactive power compensation device or unit for weak busbars The transient voltage stability normalized contribution, For all effective dynamic reactive power compensation devices and new energy units, the weak busbar Total contribution.

[0098] Example 4

[0099] Based on the same inventive concept as Embodiments 1-3, this embodiment introduces a power grid transient voltage stability contribution analysis device, which includes:

[0100] The transient voltage simulation module is configured to acquire power grid operation mode data and expected fault set data, and generate transient voltage simulation curves of the power grid bus corresponding to each expected fault based on the acquired data.

[0101] The weak bus analysis module is configured to, based on the transient voltage simulation curve of the power grid bus, calculate the transient voltage stability margin of each bus after the occurrence of a anticipated fault, and obtain the weak bus under each anticipated fault.

[0102] The dynamic reactive power effective period identification module is configured to identify the dynamic reactive power effective period of the weak bus based on the dynamic change of the bus transient voltage after the expected fault occurs.

[0103] The transient voltage simulation analysis module is configured to calculate the cumulative reactive power of each dynamic reactive power compensation device and new energy unit on the weak bus during the effective period of dynamic reactive power, based on the transient voltage simulation curve of the power grid bus.

[0104] The transient voltage stability contribution calculation module is configured to obtain the reactive voltage sensitivity of each dynamic reactive power compensation device and new energy unit to the weak bus; and determine the transient voltage stability contribution of each dynamic reactive power compensation device and new energy unit to the weak bus based on the cumulative reactive power and reactive voltage sensitivity.

[0105] The specific implementation of each of the above functional modules can be found in Embodiment 2 or Embodiment 3, and will not be repeated here.

[0106] Example 5

[0107] Based on the same inventive concept as Embodiments 1-3, this embodiment introduces a computer-readable storage medium storing a computer program thereon, characterized in that, when the computer program is executed by a processor, it implements the steps of the power grid transient voltage stability contribution analysis method as described in any of Embodiments 1-3.

[0108] 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.

[0109] 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, create means for implementing the functions specified in one or more blocks of the flowchart illustrations and / or one or more blocks of the block diagrams.

[0110] 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 that implement the functions specified in one or more flowcharts and / or one or more block diagrams.

[0111] 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 one or more flowcharts and / or one or more block diagrams.

[0112] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A method for analyzing the contribution of transient voltage stability in a power grid, characterized in that, include: Acquire power grid operation mode data and expected fault set data, and generate power grid bus transient voltage simulation curves corresponding to each expected fault based on the acquired data; Based on the simulated transient voltage curves of the power grid busbars, the transient voltage stability margins of each busbar after a anticipated fault are calculated to identify the weak busbars under each anticipated fault. Based on the dynamic changes in the transient voltage of the busbars after the anticipated fault, the effective period of dynamic reactive power for the weak busbars is identified. Based on the simulated transient voltage curves of the power grid busbars, the cumulative reactive power of each dynamic reactive power compensation device and renewable energy unit to the weak busbars during the effective period of dynamic reactive power is calculated. The reactive voltage sensitivity of each dynamic reactive power compensation device and renewable energy unit to the weak busbars is obtained. Based on the cumulative reactive power and reactive voltage sensitivity, the contribution of each dynamic reactive power compensation device and renewable energy unit to the transient voltage stability of the weak busbars is determined.

2. The method for analyzing the contribution of power grid transient voltage stability according to claim 1, characterized in that, Based on the accumulated reactive power and reactive voltage sensitivity, determine the contribution of each dynamic reactive power compensation device and new energy unit to the transient voltage stability of the weak bus, including: determining the effective reactive power compensation device and new energy unit based on the reactive voltage sensitivity; and determining the contribution of each effective reactive power compensation device and new energy unit to the transient voltage stability of the weak bus based on the accumulated reactive power and reactive voltage sensitivity of each effective reactive power compensation device and new energy unit.

3. The method for analyzing the contribution of power grid transient voltage stability according to claim 2, characterized in that, Determining effective reactive power compensation devices and new energy generator units based on the reactive power voltage sensitivity includes: identifying reactive power compensation devices and new energy generator units with reactive power voltage sensitivity greater than a preset sensitivity threshold as effective reactive power compensation devices and effective new energy generator units.

4. The method for analyzing the contribution of power grid transient voltage stability according to claim 1, characterized in that, The step of calculating the transient voltage stability margin of each bus after the occurrence of a anticipated fault to obtain the weak bus under each anticipated fault includes: for each anticipated fault in the anticipated fault set, calculating the transient voltage stability margin of each bus after the occurrence of the anticipated fault according to the transient voltage simulation curve of the corresponding power grid bus, and taking the bus with the lowest transient voltage stability margin as the weak bus under the corresponding anticipated fault.

5. The method for analyzing the contribution of power grid transient voltage stability according to claim 1, characterized in that, The step of identifying the effective period of dynamic reactive power of the weak bus based on the dynamic change of the bus transient voltage after the expected fault occurs includes: taking the time of the expected fault occurrence as the starting point of the effective period of dynamic reactive power; determining whether the transient voltage of the weak bus can recover to a preset reference value after the expected fault occurs based on the simulation curve of the transient voltage of the power grid bus; if the transient voltage of the weak bus can recover to the preset reference value, then the moment when the voltage of the weak bus first recovers to the preset voltage threshold after the expected fault occurs is determined as the end point of the effective period of dynamic reactive power; if the transient voltage of the weak bus cannot recover to the preset reference value, then the end point of the effective period of dynamic reactive power is determined according to the preset transient voltage steady-state criterion.

6. The method for analyzing the contribution of power grid transient voltage stability according to claim 5, characterized in that, The step of determining the endpoint of the effective period of dynamic reactive power based on the preset transient voltage steady-state criterion includes: determining whether there are m consecutive weak bus transient voltage sampling points that satisfy the transient voltage steady-state criterion within a preset observation period after the expected fault occurs; if so, then the m-th sampling point is selected as the endpoint of the dynamic reactive power steady-state criterion. The sampling time corresponding to the transient voltage sampling point of each weak busbar , serving as the end point of the effective period of dynamic reactive power; the transient voltage steady-state criterion is expressed as: ,in, Let n be the transient voltage of the weak busbar at sampling point n. Let n be the transient voltage of the weak busbar at the next sampling point. The preset deviation threshold value, This represents the number of consecutive sampling points at which the transient voltage of the weak busbar enters a steady state.

7. The method for analyzing the contribution of power grid transient voltage stability according to claim 6, characterized in that, The step of determining the end point of the effective period of dynamic reactive power based on the preset transient voltage steady-state criterion further includes: if, within a preset observation period after the anticipated fault occurs, there are no consecutive m weak bus transient voltage sampling points that satisfy the transient voltage steady-state criterion, then the end time of the preset observation period is taken as the end point of the effective period of dynamic reactive power, expressed as: ,in, This marks the end of the effective period for dynamic reactive power. This marks the starting point of the effective period for dynamic reactive power. The preset observation time is [the time frame].

8. The method for analyzing the contribution of power grid transient voltage stability according to claim 1, characterized in that, Based on the simulation curve of the transient voltage of the power grid bus, the cumulative reactive power of each dynamic reactive power compensation device and new energy unit on the weak bus during the effective period of dynamic reactive power is calculated. The calculation formula is as follows: In the formula, To be in the dynamic reactive power effective period Inner A dynamic reactive power compensation device or new energy unit for weak busbars Reactive power accumulation ， and These represent the start and end points of the effective period for dynamic reactive power, respectively. and They are respectively and Index of the corresponding weak bus transient voltage sampling points; For the first A dynamic reactive power compensation device or new energy unit at a weak busbar The effort wasted wasted. To prevent the failure from occurring A dynamic reactive power compensation device or the steady-state output of a new energy unit.

9. The method for analyzing the contribution of power grid transient voltage stability according to claim 1, characterized in that, Based on the accumulated reactive power and reactive voltage sensitivity, the contribution of each dynamic reactive power compensation device and new energy unit to the transient voltage stability of the weak bus is determined by the following formula: In the formula, For the first A dynamic reactive power compensation device or unit for the weak busbar The contribution of transient voltage stability, For the first A dynamic reactive power compensation device or unit for the weak busbar The reactive voltage sensitivity coefficient; For the first A dynamic reactive power compensation device or new energy unit provides power to the weak busbar during the effective period of dynamic reactive power. The reactive power accumulated.

10. The method for analyzing the contribution of power grid transient voltage stability according to claim 9, characterized in that, Based on the accumulated reactive power and reactive voltage sensitivity, the contribution of each dynamic reactive power compensation device and new energy unit to the transient voltage stability of the weak bus is determined. This also includes normalizing the calculated transient voltage stability contribution data using the following formula: In the formula, For the first A dynamic reactive power compensation device or unit for the weak busbar The transient voltage stability normalized contribution, For all dynamic reactive power compensation devices and new energy units to be evaluated, and for weak busbars Total contribution.

11. A device for analyzing the contribution of power grid transient voltage stability, characterized in that, include: The transient voltage simulation module is configured to acquire power grid operation mode data and anticipated fault set data, and generate transient voltage simulation curves for each anticipated fault corresponding to the power grid bus. The weak bus analysis module is configured to calculate the transient voltage stability margin of each bus after the anticipated fault occurs, based on the transient voltage simulation curves of the power grid bus, to obtain the weak bus under each anticipated fault. The dynamic reactive power effective time period identification module is configured to identify the dynamic changes in the bus transient voltage after the anticipated fault occurs. The system includes a dynamic reactive power effective period period; a transient voltage simulation analysis module, configured to calculate the cumulative reactive power of each dynamic reactive power compensation device and new energy unit to the weak bus during the dynamic reactive power effective period period based on the transient voltage simulation curve of the power grid bus; and a transient voltage stability contribution calculation module, configured to obtain the reactive voltage sensitivity of each dynamic reactive power compensation device and new energy unit to the weak bus; and determine the transient voltage stability contribution of each dynamic reactive power compensation device and new energy unit to the weak bus based on the cumulative reactive power and reactive voltage sensitivity.

12. The power grid transient voltage stability contribution analysis device according to claim 11, characterized in that, The transient voltage stability contribution calculation module determines the transient voltage stability contribution of each dynamic reactive power compensation device and new energy unit to the weak bus based on the reactive power accumulation and reactive voltage sensitivity. This includes: determining the effective reactive power compensation devices and new energy units based on the reactive voltage sensitivity; and determining the transient voltage stability contribution of each effective reactive power compensation device and new energy unit to the weak bus based on the reactive power accumulation and reactive voltage sensitivity of each effective reactive power compensation device and new energy unit.

13. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the power grid transient voltage stability contribution analysis method as described in any one of claims 1-10.

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