Power grid transient voltage stability control method based on power grid partition classification dynamic reactive power reserve and medium

Abstract

The invention discloses a power grid transient voltage stability control method based on power grid partition classification dynamic reactive power reserve and a medium, and relates to a power system safety and stability evaluation and transient voltage control method. The method comprises the following steps: dividing power grid partitions based on acquired power grid voltage fault data, and calculating peak faults of the power grid partitions; according to the transient voltage severity index under the peak fault, recording the minimum demand adjusted to the transient voltage stable state limit value; calculating the maximum effective quantity of the dynamic reactive power reserve according to the minimum demand quantity, and comparing the maximum effective quantity with the minimum demand quantity to evaluate the transient voltage state of the system; and outputting a power grid partition dynamic regulation instruction to control a system operation point regulation state through the coordinated optimization control model based on the dynamic reactive power reserve minimum demand quantity. According to the method, the minimum demand quantity of the dynamic reactive power reserve is taken as a transient voltage stability constraint, a partition classification dynamic reactive power reserve coordinated optimization control model for improving transient voltage stability is constructed, and the transient voltage stability of a power grid is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to a power system safety and stability evaluation and transient voltage control method, in particular to a power grid transient voltage stability control method based on power grid partition classification dynamic reactive power reserve and medium. BACKGROUND

[0002] With the continuous expansion of high proportion of renewable energy grid connection and cross-region DC transmission scale, the structure and operation characteristics of modern power system, especially the receiving end power grid, are undergoing profound changes. Large-scale replacement of local conventional synchronous units by new energy units has significantly weakened the system rotational inertia and reactive voltage support capability. At the same time, the power grid is facing increasingly serious transient voltage stability problems when it is subjected to large disturbance faults: during and after the fault is removed, the DC converter station will exhibit "reactive load" characteristics and absorb a large amount of system reactive power; the widespread induction motor load in the power grid will also increase reactive power consumption during deceleration. This sudden increase in reactive power demand in the transient process, combined with the decline in system reactive power supply capacity, constitutes the main contradiction in the safe and stable operation of the current power grid.

[0003] The core of transient voltage stability lies in the balance of dynamic reactive power. However, unlike conventional synchronous generators, which have the ability to quickly provide emergency reactive power support through strong excitation systems, wind power, photovoltaic and other new energy units connected through power electronic devices have their reactive power output capacity limited by the capacity of the converter, and the control system is difficult to provide effective reactive power support in the transient process of milliseconds to seconds, and even may exacerbate the system's reactive power shortage due to its low voltage ride-through process or disconnection. Therefore, accurately calculating the minimum amount of dynamic effective reactive power reserve necessary to maintain the transient voltage stability of the power grid and optimizing control accordingly has become a core issue in the field of safety defense for power grids with high proportion of new energy.

[0004] The research and application of dynamic reactive power reserve can be divided into two categories according to its time scale: the first category is the effective reactive power reserve for long time scale, which is suitable for static voltage stability analysis. The first literature "Analysis and Calculation of Effective Reactive Power Reserve of Generators" (Power System Automation, 2011, Vol. 35, No. 15, pp. 14) and the second literature "Model and Method of Reactive Power and Voltage Control Considering Dynamic Reactive Power Reserve in Each Area" (Power Automation Equipment, 2015, Vol. 35, No. 5, pp. 101) proposed the concept and calculation method of effective reactive power reserve, mainly focusing on the sustainable reactive power capacity of the reactive power source in steady state. The second category is the dynamic reactive power reserve for short time scale, which is suitable for transient voltage stability analysis. The fifth literature "Optimization Method of Dynamic Reactive Power Reserve for Improving Transient Voltage Security Level" (Proceedings of the CSEE, 2014, Vol. 34, No. 1, pp. 116) mainly focuses on the short-term increase of reactive power of the reactive power source in the transient process after fault, and defines the dynamic reactive power reserve of the generator in the transient time scale as the actual increase of reactive power of the generator in the transient process under a certain fault. The first literature builds a day-ahead reactive power optimization model considering dynamic reactive power reserve in each area, the core of which is to use the deterministic algorithm of branch and bound-primal-dual interior point method to accurately handle the discrete variables and their complex time period coupling constraints such as the number of actions throughout the day, successfully transforming the multi-time period dynamic optimization problem into a series of continuous variable sub-problems for efficient solution. The second literature proposes a multi-time scale dynamic optimization framework based on model predictive control for distribution networks with high proportion of renewable distributed power. The work designs a two-level structure including day-ahead optimization and real-time rolling control, fully utilizes the fast reactive power regulation capability of high proportion of renewable distributed power for "small-scale regulation", and effectively weakens the influence of prediction error through feedback correction mechanism, significantly improving the robustness of control and voltage quality. The research perspective of the third literature focuses on the voltage stability problem of the receiving end power grid of ultra-high voltage direct current, and mainly discusses the application and coordinated control of the new generation of large-capacity phase modulation machine. The article designs a multi-time scale coordinated control system covering transient, transition and steady state, and uses the fast reactive power support of the phase modulation machine as a stable control means, enriching the "second and third lines of defense" of power grid security defense. The fourth literature proposes a static reactive power optimization model considering dynamic reactive power reserve in each area. This research accurately calculates the "effective reactive power reserve" of the reactive power source through the voltage-power curve method, and uses it as both the objective function and the constraint condition, so as to ensure that each area has balanced and sufficient reactive power reserve while optimizing the economy and voltage quality, avoiding the risk of local voltage instability.

[0005] The above literatures mainly focus on dynamic reactive power reserve in long time scale, and there is little research on dynamic reactive power reserve in short time scale. Moreover, there is a lack of calculation methods for the minimum demand of dynamic reactive power reserve in both time scales and dynamic optimization control methods for transient voltage. SUMMARY

[0006] The application aims to provide a power grid transient voltage stability control method and medium based on power grid partition classification dynamic reactive reserve, which builds a coordinated optimization model and calculates the minimum demand of dynamic reactive reserve of each power grid partition, ensures efficient use of power grid reactive reserve resources, and improves the evaluation level and optimization control ability of power grid transient voltage stability.

[0007] To achieve the above-mentioned purpose, the application is implemented by using the following technical scheme.

[0008] In a first aspect, the application provides a power grid transient voltage stability control method based on power grid partition classification dynamic reactive reserve, comprising:

[0009] calculating the transient voltage severity index of each node based on the obtained power grid voltage fault data;

[0010] calculating the transient electrical distance based on the transient voltage severity index, dividing the power grid partition, and calculating the peak fault of each power grid partition;

[0011] According to the transient voltage severity index under the peak fault, the minimum demand adjusted to the transient voltage stability state limit value is obtained;

[0012] Based on the minimum demand, the dynamic effective reactive reserve of the power grid partition is calculated, and the maximum effective amount of dynamic reactive reserve of the power grid partition is calculated;

[0013] Compare the maximum effective amount of dynamic reactive reserve of the power grid partition with the minimum demand to evaluate the system transient voltage state;

[0014] Based on the maximum effective amount of dynamic reactive reserve, the minimum demand of the power grid partition, and the system transient voltage state, a coordinated optimization control model is used to output power grid partition dynamic adjustment instructions to controllable dynamic reactive sources to adjust the control system state.

[0015] Optionally, the calculation of the transient voltage severity index of each node based on the obtained power grid voltage fault data comprises:

[0016] Based on the obtained power grid voltage fault data, build a transient voltage binary table of seconds and tens of seconds respectively;

[0017] Based on the obtained power grid voltage fault data, obtain the voltage disturbance trajectory of each node fault in the power grid through time domain simulation;

[0018] Based on the voltage disturbance trajectory and the transient voltage binary table, the transient voltage severity index is calculated.

[0019] The transient voltage binary table is constructed, so that the transient voltage transformation data when the power grid fault occurs is accurately described, and the efficiency of calculating the transient voltage severity index is improved.

[0020] Optionally, the transient electrical distance is calculated based on the transient voltage severity index, the power grid partition is divided, and the peak fault of each power grid partition is calculated, including:

[0021] The transient electrical distance is obtained by quantifying the transient voltage feature similarity between nodes based on the transient voltage severity index.

[0022] The power grid partition is constructed based on the transient electrical distance, and the expected fault set of each power grid partition is constructed according to the node transient voltage severity index.

[0023] The peak fault of each power grid partition is calculated based on the expected fault set by calculating the transient voltage severity index of each expected fault.

[0024] The power grid is partitioned by the transient electrical distance, which improves the transient voltage stability when the fault occurs and facilitates the calculation of the dynamic reactive power reserve of the power grid.

[0025] Optionally, the minimum demand amount adjusted to the transient voltage stability limit value is obtained according to the transient voltage severity index under the peak fault, including:

[0026] The state quantity and the transient voltage simulation process are initialized based on the peak fault and the transient voltage severity index of each power grid partition, and the preset ten-second and second effective reactive power reserve state quantity is preset.

[0027] The preset second effective reactive power reserve state quantity is adjusted to the transient voltage stability limit value based on the node voltage trajectory, and the second minimum demand amount is obtained.

[0028] The preset ten-second effective reactive power reserve state quantity is adjusted to the transient voltage stability limit value based on the node voltage trajectory, and the ten-second minimum demand amount is obtained.

[0029] By presetting the effective reactive power reserve state quantity and optimizing the adjustment, the minimum demand amount of the transient voltage limit value when the peak fault occurs is accurately obtained.

[0030] Optionally, the dynamic effective reactive power reserve of the power grid partition is calculated based on the minimum demand amount, including:

[0031] The dynamic effective reactive power reserve of each dynamic reactive power source in the power grid partition is calculated according to the minimum demand amount.

[0032] The electrical sensitivity of the transient voltage drop peak node of each dynamic reactive power source in the power grid partition is calculated according to the minimum demand amount.

[0033] The dynamic effective reactive power reserve of the dynamic reactive power source and the electrical sensitivity are calculated to obtain the dynamic effective reactive power reserve of the power grid partition.

[0034] The calculation efficiency and accuracy of the dynamic effective reactive power reserve of the power grid partition are improved by calculating the dynamic effective reactive power reserve of the dynamic reactive power source in the power grid partition.

[0035] Optionally, the dynamic effective reactive power reserve of each dynamic reactive power source in the power grid partition is calculated according to the minimum demand, comprising:

[0036] The ten-second-level dynamic effective reactive power reserve of the dynamic reactive power source in the power grid partition is calculated, and the formula is:

[0037] (1)

[0038] Wherein, is the ten-second-level dynamic effective reactive power reserve value of the mth dynamic reactive power source, is the upper limit value of the reactive power output of the mth dynamic reactive power source in the partition k; and is the steady-state reactive power output of the mth dynamic reactive power source in the partition k. The second-level dynamic effective reactive power reserve of the dynamic reactive power source in the power grid partition is calculated, and the formula is:

[0039]

[0040] (2)

[0041] Wherein, is the second-level dynamic effective reactive power reserve value of the mth dynamic reactive power source, is the upper limit value of the reactive power output of the mth dynamic reactive power source in the partition k; and is the steady-state reactive power output of the mth dynamic reactive power source in the partition k. The electrical sensitivity of the transient voltage drop peak node of each dynamic reactive power source in the power grid partition is calculated according to the minimum demand, comprising:

[0042] The electrical sensitivity of the dynamic reactive power source node to the ten-second-level transient voltage drop peak node in the power grid partition is calculated, and the formula is:

[0043]

[0044] (3)

[0045] Wherein, is the electrical sensitivity of the dynamic reactive power source node to the ten-second-level transient voltage drop peak node, is the electrical sensitivity of the dynamic reactive power source node to the ten-second-level transient voltage drop peak node, is the electrical sensitivity of the dynamic reactive power source node to the ten-second-level transient voltage drop peak node. ​​​​​​​​voltage offset of the dynamic reactive power source node voltage offset of the voltage dip peak node voltage offset of the voltage dip peak node voltage offset of the voltage dip peak node voltage offset of the voltage dip peak node voltage offset of the voltage dip peak node

[0046] The electrical sensitivity of the dynamic reactive power source node in the power grid partition to the second-level transient voltage dip peak node is calculated, and the formula is:

[0047] (4)

[0048] wherein, voltage offset of the dynamic reactive power source node voltage offset of the dynamic reactive power source node voltage offset of the dynamic reactive power source node voltage offset of the dynamic reactive power source node voltage offset of the dynamic reactive power source node voltage offset of the dynamic reactive power source node voltage offset of the dynamic reactive power source node voltage offset of the dynamic reactive power source node voltage offset of the dynamic reactive power source node

[0049] The dynamic effective reactive power reserve of the power grid partition is calculated based on the effective reactive power reserve and the electrical sensitivity of the dynamic reactive power source, including:

[0050] The ten-second-level dynamic effective reactive power reserve of the power grid partition is calculated, and the formula is:

[0051] (5)

[0052] wherein, total amount of the ten-second-level dynamic reactive power source in the power grid partition total amount of the ten-second-level dynamic reactive power source in the power grid partition ten-second-level dynamic effective reactive power reserve of the power grid partition

[0053] The second-level dynamic effective reactive power reserve of the power grid partition is calculated, and the formula is:

[0054] (6)

[0055] wherein, total amount of the second-level dynamic reactive power source in the power grid partition total amount of the second-level dynamic reactive power source in the power grid partition second-level dynamic effective reactive power reserve of the power grid partition

[0056] The accuracy of the transient voltage stability evaluation result is ensured by calculating the effective reactive power reserve of the power grid partition.

[0057] ​Optionally, the coordinated optimization control model solves the dynamic adjustment parameter of the power grid partition by constructing an explicit mapping function between the maximum effective amount of reactive power reserve of the power grid partition and the steady-state output of the reactive power source.

[0058] The construction method of the explicit mapping function comprises:

[0059] Generating a plurality of system operation mode samples based on the steady-state reactive power output of the controllable dynamic reactive power in the power grid partition;

[0060] Calculating the maximum effective value of the dynamic reactive power reserve of the power grid partition under the transient voltage stability state limit based on the system operation mode samples;

[0061] Constructing a data set based on the maximum effective value of the dynamic reactive power reserve of the power grid partition;

[0062] Based on the data set, the explicit mapping function between the maximum effective amount of reactive power reserve of the power grid partition and the steady-state output of the reactive power source is constructed by the least square method and the linear regression algorithm.

[0063] By constructing the explicit mapping function between the dynamic reactive power reserve of the power grid partition and the steady-state reactive power output of the reactive power source, the time-domain simulation calculation in the optimization control model solving process is avoided, and the solving efficiency of the coordinated optimization control model is improved.

[0064] Optionally, the objective function of the coordinated optimization control model is:

[0065] (7)

[0066] Wherein, the maximum effective amount of dynamic reactive power reserve of the power grid partition k includes the maximum effective amount of second-level dynamic reactive power reserve And the maximum effective amount of ten-second-level dynamic reactive power reserve ; N is the total number of power grid partitions; B is the system active network loss; , And are the weight coefficients of each optimization objective; , , are the optimal values of the three explicit mapping functions, and the calculation formula of the explicit mapping function is:

[0067] (8)

[0068] Wherein, is a vector composed of the steady-state output of each reactive power source in the power grid partition , And are the coefficients and intercepts obtained by regression calculation.

[0069] Optionally, the solution process of the coordinated optimization control model includes multiple constraints, including:

[0070] Power flow equation constraints, the calculation formula is as follows: (9)

[0071] (10)

[0072] in: and They are nodes The active power and reactive power of the dynamic reactive power source; For nodes The voltage amplitude; For nodes Harmony Voltage phase angle difference between them; and They are nodes and Mutual conductance and susceptance between them; For nodes The reactive power of the reactive power compensation device; and These are the active power fed into the DC system and the reactive power consumed by the DC converter station, respectively. and They are nodes The active and reactive power consumed by the load; This represents the total number of system nodes. This represents the total number of nodes adjacent to the current node.

[0074] Operational constraints:

[0075] (11)

[0076] in: and They are nodes Upper and lower limits of voltage, For nodes The real-time voltage value;

[0077] Upper and lower limits constraints for control variables:

[0078] (12)

[0079] (13)

[0080] in: , These are synchronous rotating reactive power sources. The upper and lower limits of reactive power output; , These are power electronic reactive power sources. The upper and lower limits of reactive power output; Synchronous rotating reactive power source Unproductive efforts Power electronic reactive power sources Unproductive efforts This represents the total number of system nodes.

[0081] In a second aspect, the present invention provides a computer-readable storage medium having a computer program or instructions stored thereon, which, when executed by a processor, implements the steps of the power grid transient voltage stability assessment and control method based on power grid zoning and classification dynamic reactive power reserve described in the first aspect.

[0082] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0083] This invention improves local voltage stability and facilitates dynamic reactive power regulation by calculating the transient electrical distance and then dividing the power grid into zones based on the voltage severity index at nodes. It also improves the utilization rate of reactive power reserve resources by calculating dynamic reactive power reserves. Furthermore, it ensures dynamic regulation of the power grid by scheduling controllable dynamic reactive power sources through a coordinated optimization control model. By using the minimum demand for dynamic reactive power reserves as a transient voltage stability constraint, this invention constructs a zoned and categorized coordinated optimization control model for dynamic reactive power reserves to improve transient voltage stability. This ensures efficient reactive power regulation during faults and enhances the transient voltage stability of the power grid. Attached Figure Description

[0084] Figure 1 It is the overall framework flowchart;

[0085] Figure 2 This is a flowchart of the method for determining the critical state of transient voltage stability in a partitioned area. Detailed Implementation

[0086] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present invention and the specific features in the embodiments are detailed descriptions of the technical solution of the present invention, rather than limitations thereof. In the absence of conflict, the embodiments of the present invention and the technical features in the embodiments can be combined with each other.

[0087] The term "and / or", only describes the association relation of the associated objects, which means that there can be three relations, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " generally represents that the associated objects before and after are in an "or" relationship.

[0088] Embodiment 1

[0089] The embodiment introduces a power grid transient voltage stability evaluation and control method based on power grid partition classification dynamic reactive power reserve, which includes:

[0090] Based on the obtained power grid voltage fault data, a transient voltage binary table is constructed at the level of seconds and ten seconds, respectively;

[0091] Based on the obtained power grid voltage fault data, the voltage disturbance trajectory of each node in the power grid at the time of fault is obtained through time domain simulation;

[0092] Based on the voltage disturbance trajectory and the transient voltage binary table, the transient voltage severity index is calculated. By constructing the transient voltage binary table, the transient voltage transformation data when the power grid fault occurs is accurately described, and the efficiency of calculating the transient voltage severity index is improved.

[0093] Based on the transient voltage severity index, the transient electrical distance is calculated, the power grid partition is divided, and the peak fault of each power grid partition is calculated; specifically including:

[0094] Based on the transient voltage severity index, the transient electrical distance is obtained by quantifying the transient voltage feature similarity between nodes through cosine similarity;

[0095] Based on the transient electrical distance, the power grid partition is constructed, and the expected fault set of each power grid partition is constructed according to the node transient voltage severity index;

[0096] Based on the expected fault set, the transient voltage severity index of each expected fault is calculated to obtain the peak fault of each power grid partition. By partitioning the power grid through the transient electrical distance, the transient voltage stability when the fault occurs is improved, and it is convenient to calculate the dynamic reactive power reserve of the power grid. By pre-setting the effective reactive power reserve state quantity and optimizing the adjustment, the minimum demand quantity of the transient voltage limit value when the peak fault occurs is accurately obtained.

[0097] According to the transient voltage severity index under the peak fault, the minimum demand quantity of adjusting to the transient voltage stability limit value is obtained;

[0098] Based on the minimum demand quantity, the dynamic effective reactive power reserve of the power grid partition is calculated, and the maximum effective quantity of the dynamic reactive power reserve of the power grid partition is calculated;

[0099] The maximum effective amount of dynamic reactive power reserve of the power grid partition is compared with the minimum demand to evaluate the system transient voltage state;

[0100] Based on the maximum effective amount, the minimum demand and the system transient voltage state of the dynamic reactive power reserve of the power grid partition, a coordinated optimization control model is used to output dynamic adjustment instructions of the power grid partition to controllable dynamic reactive power sources for control system state adjustment.

[0101] In summary, the embodiment divides the power grid partition by calculating the node voltage severity index and the transient electrical distance, improves the local voltage stability, and ensures the immediate response of the dynamic adjustment of the power grid reactive power when a fault occurs. The utilization rate of the power grid reactive power reserve resources is improved by calculating the dynamic reactive power reserve. The adjustment of the power grid reactive power reserve is completed by the coordinated optimization control model to schedule the controllable dynamic reactive power sources, and the dynamic regulation of the power grid is ensured.

[0102] Embodiment 2

[0103] The embodiment introduces a power grid transient voltage stability control method based on classification of dynamic reactive power reserve of power grid partition,

[0104] As Figure 1 shown, the method specifically includes the following steps:

[0105] Step 1: Set up a binary table for seconds and a binary table for tens of seconds. The seconds include 1-9 seconds, and the tens of seconds include 10 seconds and 20 seconds. In this embodiment, the seconds are represented by short-term, and the tens of seconds are represented by long-term. Different node transient voltage severity indexes are constructed. For a given set of expected accidents, the most serious fault of each partition of the power grid is selected as the peak fault.

[0106] Step 1-1: In order to reflect the short-term and long-term transient voltage stability requirements, two binary tables of short-term and long-term are set up:

[0107] The short-term binary table is represented as . Wherein is the short-term transient voltage threshold value; is the longest duration allowed for the short-term transient voltage to be below the threshold value. This binary table is used to evaluate whether the voltage can recover to stability in a longer time scale.

[0108] The long-term binary table is represented as . Wherein is the long-term transient voltage threshold value; is the longest duration allowed for the long-term transient voltage to be below the threshold value. This binary table is used to evaluate whether the voltage meets the tolerance requirements of sensitive equipment in the rapid drop phase after the fault.

[0109] Step 1-2: Constructing the node transient voltage severity index. For a given set of contingency, the voltage trajectories of each node in the power grid under different faults are obtained by time-domain simulation, and the long-term and short-term transient voltage severity indexes are calculated according to the binary table set in step 1-1 、 .

[0110] (14)

[0111] wherein: is the voltage trajectory in the long-term binary table corresponding to the out-of-limit area in the sub-region; is the critical area corresponding to the long-term binary table; is the time when the voltage first falls below in the voltage drop phase; is the second time when the voltage rises above in the voltage rise phase, is the rated voltage of the node.

[0112] (15)

[0113] wherein: is the voltage trajectory in the long-term binary table corresponding to the out-of-limit area in the sub-region; is the critical area corresponding to the long-term binary table; is the time when the voltage first falls below in the voltage drop phase; is the second time when the voltage rises above in the voltage rise phase, is the rated voltage of the node. The judgment basis: if , it indicates that the node voltage trajectory meets the requirements of the binary table; if , it indicates that it does not meet the requirements, and there is a risk of transient voltage instability.

[0114] Step 1-3: Setting the power grid partition of transient electrical distance and constructing the transient voltage feature vector of the node , wherein: is the transient voltage feature vector of the node ; and is the total number of faults in the set of contingencies. The cosine similarity is used to quantify the transient voltage feature similarity between nodes , as the transient electrical distance .

[0115] (16)

[0116] in, For nodes transient voltage eigenvector

[0117] Steps 1-4: Set the set of anticipated faults for each partition. For example, for partition... Its fault set is as follows:

[0118] (17)

[0119] In the formula, For partitioning The One fault, For partitioning Total number of internal faults. Time-domain simulation calculations are performed for each fault to obtain the voltage disturbance trajectory of nodes within the corresponding partition under each fault. Based on the voltage disturbance trajectory, transient voltage severity indices of long-term and short-term binary tables at the 20-second and 2-second levels are calculated. For example, for fault... Then we have:

[0120] (18)

[0121] ·· (19)

[0122] In the formula, , The faults are respectively Lower partition Set of severity indices for transient voltage at internal nodes, at the 20-second and 2-second levels. , The faults are respectively Lower partition The first The severity indicators of transient voltage at each node at the 20-second and 2-second levels. For partitioning Number of internal nodes;

[0123] Steps 1-5: Filter the nodes with the most severe transient voltage drops (20 seconds and 2 seconds) under each fault condition. For example, for fault... Take respectively , Maximum value in the set , And record the node corresponding to the maximum value, respectively , These are recorded as the nodes with the most severe transient voltage drops in the 20-second and 2-second time ranges, respectively.

[0124] (20)

[0125] (twenty one)

[0126] Filter the most severe faults in each zone; calculate the transient voltage severity index for each zone, for example, for each zone... , will fault The most severe transient voltage drop node values ​​at the 20-second and 2-second levels were subjected to simple normalization:

[0127] (twenty two)

[0128] In the formula, Fault The severity index of transient voltage in the sub-region; The weighting coefficients for the severity index of transient voltage at the 20-second level. The weighting coefficient for the severity index of 2-second transient voltage;

[0129] Calculate the set of anticipated faults After all faults are resolved, then:

[0130] (twenty three)

[0131] In the formula, For partitioning A set of severity indicators for zonal transient voltages under all fault conditions; screening. The maximum value in And record the corresponding fault as partition. Most serious fault The most severe fault mentioned is the peak fault.

[0132] (twenty four)

[0133] Step 2: As Figure 2 As shown, based on the approximation of the short-term and long-term transient voltage severity indices to the threshold value under the most severe fault in the power grid section, a certain adjustment amount is applied successively to make the transient voltage under the most severe fault in the power grid section stably approach its critical state, thereby obtaining the power grid section The minimum requirement for transient voltage stability state limits, and in grid zoning Calculate the power grid partition after calculation The minimum requirement for transient voltage stability limits is calculated until all grid zones are calculated; the dynamic reactive power reserve under peak fault voltage is the minimum requirement; reference Figure 2 Further step 2

[0134] Step 2-1: Approaching the transient voltage stabilization critical state, the critical state including:

[0135] Short-term recovery time limit state, i.e. the maximum duration of transient voltage fault;

[0136] Short-term recovery time limit state, i.e. the maximum duration of transient voltage fault;

[0137] Short-term recovery time limit state, i.e. the maximum duration of transient voltage fault; and Short-term recovery time limit state, i.e. the maximum duration of transient voltage fault; Short-term recovery time limit state, i.e. the maximum duration of transient voltage fault. Step 2-2: Short-term critical state judgment and adjustment. Step 2-2-1: Calculate the maximum value of the long-term transient voltage severity index of the current fault partition . Step 2-2-2: Determine and adjust the range, greater than 1, the partition cannot meet the short-term binary table requirements, the short-term transient voltage is unstable. Proceed to step 2-2-3; less than 1 and greater than the threshold value 1 minus the margin , the partition can meet the short-term binary table, and has approached the critical state, go to step 2-3. Less than the threshold 1 minus the margin , the partition is second-level transient voltage stable, but not a critical state, there is still a margin, set the short-term effective reactive power reserve state variable to 1, and proceed to step 2-2-4.

[0138] Step 2-2-3: Determine whether the long-term dynamic effective reactive power reserve state variable is equal to 0, equal to 0, then add a phase modifier to the node , return to step 2-1 and re-run the process, not equal to 0, cancel the last iteration adjustment amount, and proceed to step 2-3;

[0139] Step 2-2-4: Select the generator or phase modifier that contributes the least to the long-term transient voltage stability of the partition. Calculate the reactive power output of each unit at the time of 2S after fault removal compared to the pre-fault reactive power increment . Select the generator / phase modifier with the smallest increment as the one with the smallest contribution. Shut down the unit . If it is a generator, its active power output is replaced by a new energy source of the same capacity. After applying the secondary adjustment amount, return to step 2-1 and proceed.

[0140] Step 2-3: Long-term critical state judgment and adjustment, the process logic is completely parallel to step 2-2.

[0141] Step 2-3-1: Calculate the maximum value of the long-term transient voltage severity index of the current fault partition .

[0142] Step 2-3-2: Judgment and Adjustment If the value is greater than 1, the partition cannot meet the requirements of the long-term binary table, and long-term transient voltage instability will occur. Proceed to step 2-3-3; if the value is less than 1 and greater than the threshold value of 1 minus the margin... If the partition satisfies the long-term binary table requirement and is close to the critical state, proceed to step 3-1. Less than the threshold 1 minus the margin. The transient voltage at the second level in the partition is stable, but not in a critical state; there is still a margin, allowing for long-term effective reactive power reserve. After setting it to 1, proceed to steps 2-3-4.

[0143] Step 2-3-3: Determine the long-term dynamic effective reactive power reserve. If it equals 0, then it's at the most critical point of the long-term indicator. After adding a STATCOM and adjusting the camera, return to step 2-1 and repeat the process. If the value is not equal to 0, cancel the adjustment amount of the previous iteration and proceed to step 3-1.

[0144] Steps 2-3-4: Select the dynamic reactive power source that contributes the least to the long-term transient voltage stability of the partition. Calculate the reactive power increase 20 seconds after the fault is cleared. Choose the reactive power source with the smallest increase in power generation. Reduce reactive power sources The upper limit of reactive power capacity is reduced, weakening its long-term reactive power support capability. After applying the adjustment, return to step 2-1.

[0145] Step 3: Calculate the maximum effective amount of short-term and long-term dynamic reactive power reserve under the minimum demand during peak faults in the power grid area; compare the minimum demand and maximum effective amount of reactive power reserve of the system to determine the transient voltage state of the system;

[0146] Step 3-1: Calculate the power grid partition after applying the adjustment. Each internal dynamic reactive power source has a dynamic effective reactive power reserve of 10 seconds or seconds:

[0147] Power grid zoning 10-second level dynamic effective reactive power reserve of internal dynamic reactive power source The dynamic reactive power source can be a generator, a synchronous condenser, or a STATCOM;

[0148] (1)

[0149] in: power grid zoning No. Each dynamic reactive power source has a dynamic effective reactive power reserve value at the ten-second level. For partitioning the mth dynamic reactive power source in the kth grid partition the upper limit of reactive power output of the mth dynamic reactive power source in the kth grid partition the steady-state reactive power output of the mth dynamic reactive power source in the kth grid partition

[0150] the kth grid partition the second-level dynamic effective reactive power reserve of the generator / phase modifier in the kth grid partition

[0151] (2)

[0152] wherein the second-level dynamic effective reactive power reserve value of the mth dynamic reactive power source, the upper limit of reactive power output of the mth dynamic reactive power source in the kth grid partition the upper limit of reactive power output of the mth dynamic reactive power source in the kth grid partition

[0153] Step 3-2: Calculate the electrical sensitivity of each dynamic reactive power source to the most serious node of transient voltage drop after applying the adjustment amount:

[0154] the kth grid partition the electrical sensitivity of the dynamic reactive power source node to the most serious node of 10-second-level transient voltage drop in the kth grid partition

[0155] (3)

[0156] wherein the electrical sensitivity of the dynamic reactive power source node to the 10-second-level transient voltage drop peak node, the voltage offset of the dynamic reactive power source node, the voltage offset of the voltage drop peak node, the reactive power injection change amount of the node

[0157] Calculate the electrical sensitivity of the generator / phase modifier node to the most serious node of second-level transient voltage drop in the kth grid partition

[0158] (4)

[0159] wherein the electrical sensitivity of the dynamic reactive power source node to the second-level transient voltage drop peak node, ​​​​​​​​​​​​​​For dynamic reactive power source nodes voltage offset, Peak voltage drop node voltage offset, For nodes The change in reactive power injection;

[0160] Step 3-3: Calculate the partition after applying the adjustment amount 10-second and second-level dynamic effective reactive power reserve:

[0161] Partition after applying adjustment amount 10-second dynamic effective reactive power reserve :

[0162] (5)

[0163] in, power grid zoning Dynamic reactive power total amount within ten seconds. Ten-second-level dynamic effective reactive power reserve for power grid zones;

[0164] (6)

[0165] in, power grid zoning Dynamic reactive power supply volume at the intrasecond level. Provides second-level dynamic effective reactive power reserve for power grid zones.

[0166] Step 4: Establish an offline data sample library, construct the mapping function relationship between the dynamic reactive power reserve of the partition and the steady-state control quantity based on the data-driven approach, take the minimum demand of the dynamic reactive power reserve as the transient voltage stability constraint, construct and solve the partition-class dynamic reactive power reserve coordinated optimization control model to improve transient voltage stability.

[0167] Step 4-1: Transient voltage stability assessment. Compare the current system state with the critical state to accurately quantify and assess the transient voltage stability of each partition of the system. Utilize the results of the previous steps for evaluation and implement optimized control.

[0168] Step 4-1-1: Calculate the maximum effective amount of dynamic reactive power reserve for each zone under the base state. Under the base state power grid operation mode without any adjustments, recalculate the maximum effective amount of short-term and long-term dynamic reactive power reserve for each zone according to Step 3-3, and denot them as follows: and .

[0169] Step 4-1-2: Calculate the maximum effective amount of dynamic reactive power reserve for each zone and determine the minimum demand corresponding to that zone. and A comparison is made. If both of the following conditions are met and , the partition is determined to be transient voltage stable under the current operating mode. If either of the above two inequalities is not true, the partition is determined to be transient voltage unstable.

[0170] Step 4-2: Construct the mapping relationship between dynamic reactive power reserve and steady-state control variable. As the short-term dynamic reactive power reserve is a transient quantity obtained by time-domain simulation, if the short-term dynamic reactive power reserve is considered in the optimization control model, the alternating solution method needs to be used, which greatly reduces the model solving efficiency. Therefore, by constructing the mapping function relationship between the partition short-term dynamic reactive power reserve and the steady-state reactive power output of the reactive power source, the time-domain simulation calculation in the optimization control model solving process is avoided, and the model solving efficiency is improved.

[0171] Step 4-2-1: Generate an offline data sample library. A large number of different system operating mode samples are generated by changing the steady-state reactive power output set value of each controllable dynamic reactive power in the partition . For each system operating mode sample , the complete process of steps two and three is adopted, including initializing the system operating mode, randomly changing the steady-state operating point of the reactive power source and performing power flow calculation, if the power flow convergence condition is met, the maximum effective amount of dynamic reactive power reserve of the partition under the operating mode is calculated offline through time-domain simulation and critical state approximation , if not, the system operating mode is reinitialized and the steady-state operating point of the reactive power source is randomly changed until the power flow converges; through the above method, until the sample quantity reaches the set value, finally forming a data set .

[0172] Step 4-2-2: Linear regression modeling, based on the data set generated in step 4-2-1 , the least square method linear regression algorithm is used to construct the explicit mapping function between the maximum effective amount of reactive power reserve of the grid partition and the steady-state output of the reactive power source:

[0173] (8)

[0174] wherein is a vector composed of the steady-state outputs of each reactive power source in the partition , and and are the coefficients and intercepts obtained by regression.

[0175] Step 4-3: Establish and solve the coordinated optimization control model, solve an optimization problem containing transient voltage stability constraints, and obtain the optimal dispatching instruction.

[0176] Step 4-3-1: Construct the objective function of the optimization control model:

[0177] (7)

[0178] wherein: is the system active power loss; , , is the weight coefficient of each optimization objective, which can be adjusted according to actual optimization requirements, and has ; , , is the optimal value of the three sub-objective functions, i.e., the explicit mapping function, i.e., the objective value when considering a sub-objective optimally. The constraint equations are as follows:

[0179] (1) The power flow equation constraint is: (9)

[0180] (10)

[0181] wherein: and are the active power and reactive power of the generator at node ; is the voltage amplitude of node ; is the voltage phase angle difference between node and ; and are the mutual conductance and susceptance between node and ; is the reactive power of the reactive power compensation device at node ; and are the active power fed by the DC system and the reactive power consumed by the DC converter station; and are the active power and reactive power consumed by the load at node ; is the total number of system nodes, is the total number of nodes adjacent to node

[0183] (2) Operation constraints

[0184] (11)

[0185] wherein: , are the upper and lower limits of the voltage of node , for the node a real-time voltage value.

[0186] (3) Control variable upper and lower limit constraints

[0187] (12)

[0188] (13)

[0189] In the formula: , are the upper and lower limits of the reactive power output of the synchronous rotating type reactive power source ; , are the upper and lower limits of the reactive power output of the power electronic type reactive power source ; is the reactive power output of the synchronous rotating type reactive power source , is the reactive power output of the power electronic type reactive power source , is the total number of system nodes.

[0190] Step 4-3-2: As shown in Figure 1 , an optimization algorithm is used to solve the model established in step 4-3-1, and the solving process includes: calculating the Jacobian and Hessian matrices of the coordination optimization control model objective function and equation, calculating the compensation gap , if the compensation gap is less than the margin , the steady-state reactive power output set value of each controllable dynamic reactive power source is the solving result, if the compensation gap is not less than the margin , the disturbance factor in the coordination optimization control model objective function is calculated, the correction equation is calculated based on the disturbance factor, the affine direction correction step is calculated, the original variables and Lagrange multipliers of the objective function are updated, and the Jacobian and Hessian matrices of the coordination optimization control model objective function and equation are recalculated.

[0191] The solving result of the coordination optimization control model objective function is a series of optimal steady-state control quantities, i.e. the optimal steady-state reactive power output set value of each controllable dynamic reactive power source. The system can issue dispatching instructions according to the result, or the automatic control system can be executed, and the system operating point can be adjusted to the optimal state.

[0192] In summary of the above embodiments, the application calculates the minimum requirement of dynamic reactive power reserve of each power grid partition by the calculation method, simultaneously considers dynamic reactive power reserve of two time scales, and provides evaluation level and optimization control ability for effective use of power grid reactive power reserve resources and improvement of power grid transient voltage stability.

[0193] Embodiment 3

[0194] Based on the same inventive concept as Embodiments 1 and 2, this embodiment introduces a computer storage medium, which can be arranged in a server to save at least one instruction, at least one program, a code set or an instruction set for implementing at least one of the method embodiments, and the at least one instruction, the at least one program, the code set or the instruction set are loaded and executed by the processor to implement the steps of the power grid transient voltage stability control method based on power grid partition classification dynamic reactive power reserve as introduced in any one of Embodiment 1.

[0195] Optionally, in the embodiments of the application, the above storage medium can be located in at least one of the network servers of the computer network. Optionally, in the embodiments of the application, the above storage medium can include but is not limited to: a U disk, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk or an optical disk, and various media that can store program codes.

[0196] As can be seen from the technical solutions provided by the above embodiments of the present specification, the power grid transient voltage stability evaluation and control method based on power grid partition classification dynamic reactive power reserve improves local voltage stability by calculating a node voltage severity index in the power grid and then calculating a transient electrical distance to divide the power grid partitions; improves the utilization rate of power grid reactive power reserve resources by calculating the dynamic reactive power reserve amount; and ensures the dynamic regulation of the power grid by coordinating and optimizing the control model to dispatch the power grid reactive power reserve. The application constructs a partition classification dynamic reactive power reserve coordinated optimization control model for improving transient voltage stability by taking the minimum requirement of dynamic reactive power reserve as the transient voltage stability constraint, thereby providing support for improving the transient voltage stability of large power grids.

[0197] Those skilled in the art should understand that the embodiments of the application can be provided as a method, a system, or a computer program product. Therefore, the application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the application can take the form of a computer program product implemented 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.

[0198] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 one or more flow or blocks

[0199] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 one or more flow or blocks

[0200] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 one or more flow or blocks

[0201] The embodiments of the present application described above are merely intended to illustrate the present application, but not to limit the present application. The skilled in the art can make many modifications and improvements without departing from the spirit and scope of the present application, which should be protected as long as they fall within the scope of the present application.

Claims

1. A method for transient voltage stability control of a power grid based on dynamic reactive power reserve categorized by power grid region, characterized in that, include: The transient voltage severity index of each node is calculated based on the acquired power grid voltage fault data; Calculate transient electrical distances based on transient voltage severity indices, divide the power grid into zones, and calculate peak faults in each power grid zone; Based on the transient voltage severity index under the peak fault, obtain the minimum required amount to adjust to the transient voltage steady state limit; Calculate the dynamic effective reactive power reserve of the power grid zone based on the minimum demand, and calculate the maximum effective amount of dynamic reactive power reserve of the power grid zone. The maximum effective amount of dynamic reactive power reserve in the power grid section is compared with the minimum demand to assess the transient voltage state of the system. Based on the maximum effective amount and minimum demand of the dynamic reactive power reserve of the power grid zone and the transient voltage state of the system, the coordinated optimization control model is used to output the dynamic adjustment command of the power grid zone to the controllable dynamic reactive power source to adjust the state of the control system.

2. The power grid transient voltage stability control method based on dynamic reactive power reserve according to power grid zoning and classification as described in claim 1, characterized in that, The calculation of transient voltage severity indices for each node based on the acquired grid voltage fault data includes: Based on the acquired grid voltage fault data, binary tables of transient voltage at the second and ten-second levels are constructed respectively. Based on the acquired grid voltage fault data, the voltage disturbance trajectory of each node in the grid during a fault is obtained through time-domain simulation. The severity index of transient voltage is calculated based on the voltage disturbance trajectory and the transient voltage binary table.

3. The power grid transient voltage stability control method based on dynamic reactive power reserve according to power grid zoning and classification as described in claim 1, characterized in that, The calculation of transient electrical distance based on transient voltage severity index, the division of power grid zones, and the calculation of peak faults in each power grid zone include: Based on the transient voltage severity index, the transient electrical distance between nodes is obtained by quantifying the similarity of transient voltage characteristics between nodes using cosine similarity. Power grid partitions are constructed based on transient electrical distances, and a set of anticipated faults for each power grid partition is constructed based on the severity index of transient voltage at nodes. Based on the set of anticipated faults, the peak faults of each power grid zone are calculated by calculating the transient voltage severity index of each anticipated fault.

4. The power grid transient voltage stability control method based on dynamic reactive power reserve according to power grid zoning and classification as described in claim 1, characterized in that, Based on the transient voltage severity index under the peak fault, obtain the minimum required amount to adjust to the transient voltage steady-state limit, including: The initialization of state variables and transient voltage simulation process is based on the peak fault and transient voltage severity indicators of each power grid zone, and the preset effective reactive power reserve state variables at the ten-second and second levels are used. Based on the node voltage trajectory, the preset second-level effective reactive power reserve state quantity is adjusted to the transient voltage stability state limit to obtain the second-level minimum demand quantity; Based on the node voltage trajectory, the preset ten-second level effective reactive power reserve state quantity is adjusted to the transient voltage stability state limit to obtain the ten-second level minimum demand quantity.

5. The power grid transient voltage stability control method based on dynamic reactive power reserve according to power grid zoning and classification as described in claim 4, characterized in that, The dynamic effective reactive power reserve of the power grid zone is calculated based on the minimum demand, including: Calculate the dynamic effective reactive power reserve of each dynamic reactive power source within the power grid zone based on the minimum demand. Calculate the electrical sensitivity of each dynamic reactive power transient voltage drop peak node within the power grid zone based on the minimum demand. The dynamic effective reactive power reserve of the power grid zone is calculated based on the dynamic effective reactive power reserve of the dynamic reactive power source and electrical sensitivity.

6. The power grid transient voltage stability control method based on dynamic reactive power reserve according to power grid zoning and classification as described in claim 5, characterized in that, Calculate the dynamic effective reactive power reserve of each dynamic reactive power source within the power grid zone based on the minimum demand, including: Calculate power grid zoning The formula for the ten-second-level dynamic effective reactive power reserve of the internal dynamic reactive power source is: （1） in: For the first Each dynamic reactive power source has a dynamic effective reactive power reserve value at the ten-second level. For partitioning Inner The upper limit of the reactive power output of a dynamic reactive power source; The steady-state reactive power output of the m-th dynamic reactive power source in partition k; Calculate power grid zoning The formula for the second-level dynamic effective reactive power reserve of the internal dynamic reactive power source is: （2） in: For the first Each dynamic reactive power source has a second-level dynamic effective reactive power reserve value. For partitioning Inner The upper limit of reactive power output of a dynamic reactive power source; The electrical sensitivity of each dynamic reactive power source transient voltage sag peak node within the power grid zone is calculated based on the minimum demand, including: Calculate power grid zoning The electrical sensitivity of the internal dynamic reactive power source node to the peak value of a ten-second transient voltage drop is given by the following formula: （3） in, For dynamic reactive power source nodes For the peak node of transient voltage drop in the ten-second range Electrical sensitivity, For dynamic reactive power source nodes voltage offset, Peak voltage drop node voltage offset, For nodes The change in reactive power injection; Calculate power grid zoning The electrical sensitivity of the internal dynamic reactive power source node to the peak value of the second-level transient voltage drop is given by the following formula: （4） in, For dynamic reactive power source nodes Peak node of transient voltage drop in seconds Electrical sensitivity, For dynamic reactive power source nodes voltage offset, Peak voltage drop node voltage offset, For nodes The change in reactive power injection; The dynamic effective reactive power reserve of the power grid zone is calculated based on the dynamic effective reactive power reserve of dynamic reactive power sources and electrical sensitivity, including: The formula for calculating the dynamic effective reactive power reserve of a power grid zone at the ten-second level is as follows: （5） in, power grid zoning Dynamic reactive power total amount within ten seconds. Ten-second-level dynamic effective reactive power reserve for power grid zones; The formula for calculating the second-level dynamic effective reactive power reserve of a power grid zone is as follows: （6） in, power grid zoning Dynamic reactive power supply volume at the intrasecond level. Provides second-level dynamic effective reactive power reserve for power grid zones.

7. The power grid transient voltage stability control method based on dynamic reactive power reserve according to power grid zoning and classification as described in claim 1, characterized in that, The coordinated optimization control model solves for the dynamic adjustment parameters of the power grid partition by constructing an explicit mapping function between the maximum effective amount of reactive power reserve of the power grid partition and the steady-state output of the reactive power source. The method for constructing the explicit mapping function includes: Multiple system operation mode samples are generated based on the steady-state reactive power output of the controllable dynamic reactive power within the power grid partition; Based on the system operation mode sample, calculate the maximum effective value of dynamic reactive power reserve of power grid zone under transient voltage stability state limit; A dataset is constructed based on the maximum effective value of dynamic reactive power reserve for the power grid partition. Based on the dataset, an explicit mapping function between the maximum effective amount of reactive power reserve in the power grid zone and the steady-state output of reactive power sources is constructed using the least squares method and linear regression algorithm.

8. The power grid transient voltage stability control method based on dynamic reactive power reserve according to power grid zoning and classification as described in claim 1, characterized in that, The objective function of the coordinated optimization control model is: （7） Wherein: the maximum effective amount of dynamic reactive power reserve for grid partition k includes the maximum effective amount of second-level dynamic reactive power reserve. and the maximum effective amount of dynamic reactive power reserve at the ten-second level ; This represents the total number of power grid zones. For system active power loss; , and These are the weighting coefficients for each optimization objective; , , These are the optimal values ​​of three explicit mapping functions, and the formulas for calculating these explicit mapping functions are as follows: （8） in, It is a power grid zoning The vector composed of the steady-state output of each reactive power source within the system. and The coefficients and intercepts are obtained through regression calculations.

9. The power grid transient voltage stability control method based on dynamic reactive power reserve according to power grid zoning and classification as described in claim 8, characterized in that, The solution process of the coordinated optimization control model includes multiple constraints, including: Power flow equation constraints, the calculation formula is as follows: （9） （10） in: and They are nodes The active power and reactive power of the dynamic reactive power source; For nodes The voltage amplitude; For nodes Harmony Voltage phase angle difference between them; and They are nodes and Mutual conductance and susceptance between them; For nodes The reactive power of the reactive power compensation device; and These are the active power fed into the DC system and the reactive power consumed by the DC converter station, respectively. and They are nodes The active and reactive power consumed by the load; This represents the total number of system nodes. This represents the total number of nodes adjacent to the current node. Operational constraints: （11） in: and They are nodes Upper and lower limits of voltage, For nodes The real-time voltage value; Upper and lower limits constraints for control variables: （12） （13） in: , These are synchronous rotating reactive power sources. The upper and lower limits of reactive power output; , These are power electronic reactive power sources. The upper and lower limits of reactive power output; Synchronous rotating reactive power source Unproductive efforts Power electronic reactive power sources Unproductive efforts This represents the total number of system nodes.

10. A computer-readable storage medium having a computer program or instructions stored thereon, characterized in that, When the computer program or instructions are executed by the processor, they implement the steps of the power grid transient voltage stability control method based on power grid partition classification dynamic reactive power reserve as described in any one of claims 1 to 9.

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