Method and system for calculating dynamic effective reactive power reserve minimum demand quantity of power grid partition

Abstract

The invention discloses a method and a system for calculating the dynamic effective reactive power reserve minimum demand quantity of a power grid partition. The method comprises the following steps of: setting a binary table and a node transient voltage stability index for two time scales, namely a long time scale L and a short time scale S respectively; for a given anticipated fault set, screening the most serious fault of each partition of the power grid; according to the approximation condition of the node transient voltage stability indexes of the two time scales and a threshold value under the most serious fault of the partition, a certain adjustment amount is gradually applied, so that the transient voltage stability under the most serious fault of the partition approaches the critical state of the partition; and calculating the two time scale dynamic reactive power reserves after the adjustment amount is applied under the most serious fault of the partition as the minimum demand quantity of the dynamic effective reactive power reserve of the partition. According to the method, dynamic reactive power reserve of two time scales is considered at the same time, and support is provided for effective configuration and utilization of reactive power reserve resources of a power grid and improvement of transient voltage stability of a system.

Description

Technical Field

[0001] The present invention relates to the field of power system voltage stability, and particularly to a calculation method and system for the minimum demand of dynamic effective reactive power reserve in power grid partitions. Background Art

[0002] With the continuous increase in the proportion of new energy units in power generation and the scale of DC feed-in, the installed capacity of local conventional units is replaced by power electronic devices, resulting in the increasingly prominent problem of transient voltage stability in the receiving-end system. When a fault occurs in the receiving-end system, the DC system and the load need to absorb a large amount of reactive power from the system. However, the transient reactive power support provided by new energy units is limited, and large-scale disconnection from the grid may even occur, seriously threatening the safe and stable operation of the receiving-end system. Therefore, it is urgent to calculate and evaluate the minimum demand of dynamic effective reactive power reserve in each partition of the receiving-end power grid to guide the configuration and operation of dynamic reactive power compensation in the power grid.

[0003] Currently, the dynamic reactive power reserve of reactive power sources can be divided into two types according to the action time. The first is the reactive power reserve that can be continuously emitted in the long term, and its magnitude is mainly restricted by conditions such as its own reactive power capacity and operating range, and is applicable to static voltage stability problems. The second is the reactive power that can only be increased in a short time under large disturbances, and its magnitude is closely related to the dynamic characteristics of the reactive power source, mainly reflected in the strong excitation control of generators and synchronous condensers, and the transient control of devices such as STATCOM. It is applicable to transient voltage stability problems. The research on reactive power reserve mainly focuses on the dynamic reactive power reserve on a long time scale, and there is little research on the dynamic reactive power reserve on a short time scale, and there is a lack of a practical calculation method for the minimum demand of dynamic reactive power reserve on both time scales. Summary of the Invention

[0004] The technical problem to be solved by the present invention: In view of the above problems of the prior art, a calculation method and system for the minimum demand of dynamic effective reactive power reserve in power grid partitions are provided. The present invention simultaneously considers the dynamic reactive power reserves on two time scales, providing support for the effective utilization of power grid reactive power reserve resources and improving the transient voltage stability of the power grid.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows: A calculation method for the minimum demand of dynamic effective reactive power reserve in power grid partitions, comprising: Step 1: Set a binary table and a node transient voltage stability index for the long time scale L and the short time scale S respectively. The binary table is used to define the lowest threshold value of the voltage at this time scale and the longest duration that the voltage must not exceed when it is lower than this threshold value and the specified time that cannot be exceeded.

[0006] Step 2: For a given set of expected faults, screen the most serious faults in each section of the power grid; Step 3: According to the proximity of the node transient voltage stability index and the threshold value at the long time scale L and the short time scale S under the most serious fault in the partition, a certain adjustment amount is applied successively to make the transient voltage stability under the most serious fault in the partition approach its critical state; Step 4: Calculate the dynamic reactive power reserves of the long time scale L and the short time scale S after applying the adjustment amount under the most serious fault in the partition as the minimum required amount of dynamic effective reactive power reserve of the partition.

[0007] Furthermore, the step 1 comprises: Step 1-1: Set up a binary table for the long time scale L , set up a binary table for the short time scale S , where the binary representation of the long time scale L is Indicates voltage Below the threshold value of the long time scale L The maximum duration of Cannot exceed the time specified by the long time scale L , where the binary table of the short time scale S is Indicates voltage Below the threshold value of short time scale S The maximum duration of Cannot exceed the specified time of the short time scale S , and satisfies .

[0008] Step 1-2: The calculation function expression of the node transient voltage stability index set for the long time scale L is:

[0009] In the above formula, For failure Next Node Long time scale L The transient voltage stability index of the binary meter; is the area of ​​the sub-region corresponding to the binary table of the long time scale L; is the critical area corresponding to the binary table of the long time scale L; is the moment when the voltage drops below the voltage threshold of the binary meter on the long time scale L; is the moment when the voltage rises above the binary table voltage threshold value of the long time scale L, is the voltage rating; For failure Next Node The actual voltage change trajectory at time t; is the voltage threshold value of the binary table for the long time scale L; is the longest critical time for the binary table of the long time scale L to cross the voltage threshold value;

[0010] Steps 1 - 3: The calculation function expression of the node transient voltage stability index set for the short time scale S is:

[0011] In the above formula, is the fault the lower node is the transient voltage stability index of the binary table of the short time scale S; is the area of the corresponding sub - region of the binary table of the short time scale S; is the critical area corresponding to the binary table of the short time scale S; is the moment when the voltage is lower than the voltage threshold value of the binary table of the short time scale S during the voltage drop process; is the moment when the voltage is higher than the voltage threshold value of the binary table of the short time scale S during the voltage rise process, is the rated voltage; is the fault the lower node is the actual voltage change trajectory at time t; is the voltage threshold value of the binary table of the short time scale S; is the longest critical time for the binary table of the short time scale S to cross the voltage threshold value; and when the node transient voltage stability index is less than 1, it means that the node under the fault can meet the requirements of the binary table corresponding to the time scale.

[0012] Furthermore, the said step 2 includes: Step 2 - 1: Obtain the set of contingency faults for each partition. The function expression of the set of contingency faults for any partition is

[0013]

[0014] In the above formula, is the set of contingency faults for partition , is the first fault of partition , is the th fault of partition , is the th fault of partition , is the total number of faults within partition

[0015] Step 2-2: Conduct time-domain simulation calculations for each fault in the pre-conceived fault set respectively to obtain the perturbed trajectories of the node voltages in the corresponding partitions under each fault; Step 2-3: According to the perturbed trajectories of the node voltages in the corresponding partitions under the faults, calculate the node transient voltage stability indices for two time scales, namely the long time scale L and the short time scale S, to obtain the sets of node transient voltage stability indices for the long time scale L and the short time scale S:

[0016]

[0017] In the above formula, and are respectively the sets of node transient voltage stability indices for the long time scale L and the short time scale S of the nodes in partition under fault , ~ are respectively the node transient voltage stability indices for the long time scale L of the 1st to th nodes in partition under fault , is the node transient voltage stability index for the long time scale L of the th node in partition under fault , ~ are respectively the node transient voltage stability indices for the short time scale S of the 1st to th nodes in partition under fault , is the node transient voltage stability index for the short time scale S of the th node in partition under fault , is the number of nodes in partition .

[0018] Step 2-4: Take the maximum value of the set of node transient voltage stability indices for the long time scale L and record the corresponding node with the maximum value for the long time scale L , take the maximum value of the set of node transient voltage stability indices for the short time scale S and record the corresponding node with the maximum value for the short time scale S ;

[0019] Step 2-5: Calculate the partition transient voltage stability index according to the following formula:

[0020] In the above formula, is the transient voltage stability index of the partition under a fault , is the weight coefficient of the transient voltage stability index of the long time scale L, is the maximum value in the set of node transient voltage stability indexes of the long time scale L, is the weight coefficient of the transient voltage stability index of the short time scale S, is the maximum value in the set of node transient voltage stability indexes of the short time scale S.

[0021] Step 2-5: Construct the contingency set of for all contingencies in the transient voltage stability index set :

[0022]

[0023] In the above formula, ~ are the transient voltage stability indexes of the 1st to th contingencies respectively; screen out the maximum value in the set of transient voltage stability indexes of all contingencies in the contingency set of in the partition , and use the contingency corresponding to the maximum value as the most severe contingency of the partition .

[0024] Furthermore, the said Step 3 includes: Step 3-1: Set the dynamic effective reactive power reserve state variables , of two time scales, the long time scale L and the short time scale S, and set their initial values to 0;

[0025] Step 3-2: Perform time-domain simulation to calculate the most severe contingency of the partition , and obtain the voltage disturbance trajectories of each node in the partition;

[0026] Step 3-3: Calculate the transient voltage stability indexes of the long time scale L and the short time scale S based on the voltage disturbance trajectories:

[0027]

[0028] In the above formula, and are respectively the most serious faults under the partition the lower partition the set of node transient voltage stability indexes of the binary table of the long time scale L and the short time scale S of the internal nodes, and are respectively the most serious faults under the partition the lower partition the th node of the long time scale L and the short time scale S of the binary table of the node transient voltage stability index.

[0029] Step 3-4: Screen the most serious faults under each partition the nodes with the most serious transient voltage dips of the long time scale L and the short time scale S:

[0030]

[0031]

[0032] In the above formula, and are respectively the maximum values of the set of node transient voltage stability indexes of the binary table of the long time scale L and the short time scale S of the internal nodes under the most serious fault under the partition the lower partition Record the maximum value The corresponding node is used as the node with the most serious transient voltage dip of the long time scale L , the maximum value The corresponding node is used as the node with the most serious transient voltage dip of the short time scale S .

[0033] Step 3-5: Judge the size of the maximum value of the short time scale transient voltage stability index , if the maximum value is less than the threshold value 1- ( is the stability margin, 0≤ <1), then the transient voltage of the short time scale S in the partition is stable, but not in the critical state, and the dynamic effective reactive power reserve state quantity of the short time scale S is set to 1; if is greater than 1, the partition cannot meet the binary table of the short time scale S, and the transient voltage of the short time scale S is unstable, and jump to Step 3-7; if the maximum value is less than 1 and greater than the threshold value 1- , then the partition can satisfy the binary table of the short time scale S, and the transient voltage stability of the short time scale S is in a critical state, jump to step 3-8;

[0034] Step 3-6: Screen the generator or synchronous condenser with the least contribution to the transient voltage stability of the partition at the short time scale S, shut down the generator or synchronous condenser with the least contribution to the transient voltage stability of the short time scale S, and return to step 3-2 after adjustment; Step 3-7: Judge the dynamic effective reactive power reserve state quantity of the short time scale S Whether it is equal to 0, if so, install a synchronous condenser or other dynamic reactive power compensation equipment at the node with the most serious transient voltage drop in the short time scale S , and then return to step 3-2, otherwise cancel the generator or synchronous condenser shut down in step 3-6 in the previous iteration;

[0035] Step 3-8: Judge the maximum value of the long time scale transient voltage stability index If the maximum value is less than the threshold value 1 - , the transient voltage of the partition at the long time scale L is stable, but not in a critical state. Set the dynamic effective reactive power reserve state quantity of the long time scale L to 1; if is greater than 1, the partition cannot satisfy the binary table of the long time scale L, and the transient voltage at the long time scale L is unstable, jump to step 3-10; if the maximum value is less than 1 and greater than the threshold value 1 - , the partition can satisfy the binary table of the long time scale L, and the transient voltage stability of the long time scale L is in a critical state, and the calculation process ends;

[0036] Step 3-9: Screen the dynamic reactive power source with the least contribution to the transient voltage stability of the long time scale L, reduce the reactive power capacity of the dynamic reactive power source with the least contribution to the transient voltage stability of the long time scale L, and return to step 3-2 after adjustment.

[0037] Step 3-10: Judge the dynamic effective reactive power reserve state quantity of the long time scale L Whether it is equal to 0, if so, install a STATCOM or other dynamic reactive power compensation equipment at the node with the most serious transient voltage drop in the long time scale L , and then return to step 3-2, otherwise cancel the reduction of the reactive power capacity of the dynamic reactive power source in step 3-9 in the previous iteration, and end the calculation process.

[0038] Among them, screening the generator or synchronous condenser with the least contribution to the transient voltage stability of the partition at the short time scale S in step 3-6 includes: Step 3-6-1: Output the reactive power outputs of each generator and synchronous condenser within the partition at short time scale S after fault excision, and obtain the set of reactive power outputs of generators and synchronous condensers within the partition at short time scale S after fault excision :

[0039]

[0040] In the above formula, ~ are respectively the reactive power outputs of the 1st to the th generator or synchronous condenser at short time scale S after the most severe fault excision in the partition, is the reactive power output of the nth generator or synchronous condenser at short time scale S after the most severe fault excision in the partition, and is the total number of generators and synchronous condensers within the partition .

[0041] Step 3-6-2: Calculate the additional reactive power increments of each generator and synchronous condenser at short time scale S after the most severe fault excision in the partition according to the following formula: The additional reactive power increments of each generator and synchronous condenser at short time scale S after the most severe fault excision in the partition are:

[0042]

[0043] In the above formula, is the additional reactive power increment of the th generator or synchronous condenser at short time scale S after the most severe fault excision in the partition, and is the steady-state reactive power output of the th generator or synchronous condenser in the partition before the fault; according to the additional reactive power increments of each generator and synchronous condenser at short time scale S after the most severe fault excision in each partition, obtain the set of additional reactive power increments of generators and synchronous condensers at short time scale S after the most severe fault excision in the partition

[0044] .

[0044]

[0045] In the above formula, ~ are respectively the additional reactive power increments of the 1st to the th generator and synchronous condenser at short time scale S after the most severe fault excision in each partition

[0046] Step 3-6-3: Select the generator or synchronous condenser with the minimum reactive power increase at the short-term time scale S after fault clearing according to the following formula as the generator or synchronous condenser with the minimum contribution to the transient voltage stability of the partition at the short-term time scale S:

[0047] In the above formula, is the generator or synchronous condenser with the minimum contribution to the transient voltage stability of the partition at the short-term time scale S.

[0048] The dynamic reactive power sources selected in Step 3-9 with the minimum contribution to the transient voltage stability at the long-term time scale L include: Step 3-9-1: Output the reactive power outputs of each dynamic reactive power source in the partition at the long-term time scale L after fault clearing. The dynamic reactive power sources include generators, synchronous condensers, and STATCOMs, and obtain the set of reactive power outputs of dynamic reactive power sources in the partition at the long-term time scale L after fault clearing :

[0049]

[0050] In the above formula, ~ is the reactive power output of the 1st to th dynamic reactive power source in the partition at the long-term time scale L after the most severe fault clearing, is the reactive power output of the th dynamic reactive power source in the partition at the long-term time scale L after the most severe fault clearing, is the total number of dynamic reactive power sources in the partition Step 3-9-2: Calculate the reactive power increase of each dynamic reactive power source in the partition at the long-term time scale L after the most severe fault clearing according to the following formula:

[0051] In the above formula,

[0052] is the reactive power increase of the

[0053] th dynamic reactive power source in the partition at the long-term time scale L after the most severe fault clearing, is the steady-state reactive power output of the th dynamic reactive power source in the partition before the fault

[0054] And obtain the partition according to the reactive power increase of each dynamic reactive power source in the partition at the long-term time scale L after the most severe fault clearing ​​​​​​​Set of reactive power increase amounts of dynamic reactive power sources at long - time scale L after the removal of the most serious fault :

[0055]

[0056] In the above formula, ~ are respectively the reactive power increase amounts of the 1st to th dynamic reactive power sources at long - time scale L after the removal of the most serious fault in the partition

[0057] Step 3 - 9 - 3: Screen the dynamic reactive power source with the minimum reactive power increase amount at long - time scale L after the fault removal as the dynamic reactive power source with the minimum contribution to the transient voltage stability of the partition at short - time scale S:

[0058] In the above formula, is the dynamic reactive power source with the minimum contribution to the transient voltage stability of the partition at short - time scale S

[0059] Furthermore, the said Step 4 includes: Step 4 - 1: Calculate the dynamic effective reactive power reserves of each dynamic reactive power source in the partition at two time scales of long - time scale L and short - time scale S after applying the adjustment amount according to the following formula:

[0060]

[0061] In the above formula, is the dynamic effective reactive power reserve of the th dynamic reactive power source in the partition at long - time scale L, is the upper limit value of the reactive power output of the th dynamic reactive power source in the partition at long - time scale L

[0062] And determine the dynamic effective reactive power reserve of the generator or synchronous condenser in the partition at short - time scale S according to the following formula

[0063]

[0064] In the above formula, is the upper limit value of the reactive power output of the th generator or synchronous condenser in the partition at short - time scale S

[0065] Step 4 - 2: Calculate the electrical sensitivity of each dynamic reactive power source to the node with the most serious transient voltage drop at long - time scale L according to the following formula

[0066] In the above formula, is the electrical sensitivity of the th dynamic reactive power source after applying the adjustment amount to the most severely affected node of the transient voltage dip on the long time scale L , is the voltage offset of the th dynamic reactive power source, is the voltage offset of the most severely affected node of the transient voltage dip , is the change in reactive power injection of the most severely affected node of the transient voltage dip .

[0067] Calculate the electrical sensitivity of the generator or synchronous condenser node in the partition to the most severely affected node of the transient voltage dip on the short time scale S according to the following formula :

[0068]

[0069] In the above formula, is the voltage offset of the generator or synchronous condenser node , is the voltage offset of node , is the change in reactive power injection of node .

[0070] Step 4-3: Calculate the dynamic effective reactive power reserve of the partition at two time scales, namely the long time scale L and the short time scale S. Among them, the calculation function expression of the dynamic effective reactive power reserve of the partition at the long time scale L is

[0071]

[0072] The calculation function expression of the dynamic effective reactive power reserve of the partition at the short time scale S is

[0073]

[0074] Output the dynamic effective reactive power reserve of the partition at the long time scale L and the dynamic effective reactive power reserve of the partition at the short time scale S after applying the adjustment amount as the minimum required amount of the dynamic effective reactive power reserve of the partition. ​​​​

[0075] In addition, the present invention also provides a calculation system for the minimum required amount of dynamic effective reactive power reserve in power grid zoning, including a microprocessor and a memory connected to each other. The microprocessor is programmed or configured to execute the calculation method for the minimum required amount of dynamic effective reactive power reserve in power grid zoning. The present invention also provides a computer-readable storage medium, in which a computer program is stored. The computer program is used to be programmed or configured by a microprocessor to execute the calculation method for the minimum required amount of dynamic effective reactive power reserve in power grid zoning.

[0076] Compared with the prior art, the present invention mainly has the following advantages: The method of the present invention includes setting up a binary table and a node transient voltage stability index for two time scales of long time scale L and short time scale S respectively; screening the most serious faults in each power grid zone for a given set of contingency faults; according to the approximation of the node transient voltage stability indexes of the two time scales under the most serious fault in the zone to the threshold value, applying a certain adjustment amount successively to make the transient voltage stability under the most serious fault in the zone approach its critical state; calculating the dynamic reactive power reserves of the two time scales after applying the adjustment amount under the most serious fault in the zone as the minimum required amount of dynamic effective reactive power reserve in the power grid zone. The present invention takes into account the dynamic reactive power reserves of both time scales, providing support for the effective utilization of power grid reactive power reserve resources and improving the transient voltage stability of the power grid. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] Figure 1 It is a schematic diagram of the basic flow of the method of the embodiment of the present invention.

[0078] Figure 2 It is a flowchart of the method for obtaining the critical state of transient voltage stability in a zone in the embodiment of the present invention.

[0079] Figure 3 It is a schematic diagram of the detailed flow of the method of the embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0080] Hereinafter, taking the long time scale L = 10 s and the short time scale S = 1 s as examples, the calculation method and system for the minimum required amount of dynamic effective reactive power reserve in power grid zoning of the present invention will be further described in detail.

[0081] As Figure 1 shown, the calculation method for the minimum required amount of dynamic effective reactive power reserve in power grid zoning of this embodiment includes: Step 1: Set up two binary tables at the 10 - second level and the second level, and construct different node transient voltage stability indexes.

[0082] Step 1 - 1: In order to reflect the transient voltage stability requirements at the 10 - second level and the second level, it is necessary to set up binary tables at the 10 - second level and the second level: A single binary table can be expressed as: , used to represent voltage lower than the threshold value of the longest duration shall not exceed the specified time ; by setting the threshold values at the 10 - second level and the 1 - second level , , and the corresponding voltage threshold values , , finally, a binary table at the 10 - second level can be obtained , a binary table at the 1 - second level , where ; the present invention sets the binary table at the 10 - second level as [0.8 p.u., 10 s], and the binary table at the 1 - second level as [0.75 p.u., 1 s];

[0083] Step 1 - 2: Integrate and calculate the area where the voltage - disturbed trajectory exceeds the limit for the binary tables at the 10 - second level and the 1 - second level respectively, and construct transient voltage stability indicators at different time scales:

[0084] In the formula, is the transient voltage stability indicator of node under fault for the binary table at the 10 - second level; is the area of the corresponding sub - region of the binary table at the 10 - second level; is the critical area corresponding to the binary table at the 10 - second level; is the moment when the voltage is lower than the voltage threshold value of the binary table at the 10 - second level during the voltage - dropping process; is the moment when the voltage is higher than the voltage threshold value of the binary table at the 10 - second level during the voltage - rising process, is the rated voltage; is the actual voltage change trajectory of node under fault ; is the voltage threshold value of the binary table at the 10 - second level; is the longest critical time for the binary table at the 10 - second level to cross the voltage threshold value.

[0085]

[0086] In the formula, is the transient voltage stability indicator of node under fault for the binary table at the 1 - second level; is the area of the corresponding sub - region of the binary table at the 1 - second level; is the critical area corresponding to the binary table at the 1 - second level; is the moment when the voltage is lower than the voltage threshold value of the binary table at the 1 - second level during the voltage - dropping process; is the moment during the voltage rise process that is higher than the voltage threshold value of the second-level binary table. is the rated voltage; is the fault lower node actual voltage change trajectory; is the voltage threshold value of the second-level binary table; is the longest critical time for the second-level binary table to cross the voltage threshold value; the threshold values of the 10-second-level and second-level transient voltage stability indicators are both 1. When , the node can meet the requirements of the 10-second-level binary table under the fault . When , the node can meet the requirements of the second-level binary table under the fault .

[0087] Step 2: For the given set of contingency faults, screen the most severe faults in each power grid partition.

[0088] Step 2-1: Set the set of contingency faults for each partition. For example, for partition , its fault set is

[0089]

[0090] In the formula, is the th fault of partition , is the total number of faults within partition

[0091] Step 2-2: Conduct time-domain simulation calculations for each fault respectively to obtain the perturbed voltage trajectories of the nodes within the corresponding partition under each fault; Step 2-3: Calculate the transient voltage stability indicators of the 10-second-level and second-level binary tables based on the perturbed voltage trajectories. For example, for fault there are:

[0092]

[0093]

[0094] In the formula, , are the sets of 10-second-level and second-level transient voltage stability indicators of the nodes within partition under fault respectively. , are the th within partition 10-second and second-level transient voltage stability indices of each node, is the number of nodes within the sub-region.

[0095] Step 2-4: Screen the nodes with the most severe 10-second and second-level transient voltage dips under each fault. For example, for fault , respectively take the , maximum value in the set , , and record the nodes corresponding to the maximum values, which are , , respectively, and denote them as the nodes with the most severe 10-second and second-level transient voltage dips;

[0096]

[0097]

[0098] Step 2-5: Screen the most severe faults in each sub-region; Step 2-5-1: Calculate the transient voltage stability index of the sub-region. For example, for sub-region , perform simple normalization on the 10-second and second-level transient voltage dip index values of the nodes with the most severe dips under fault :

[0099]

[0100] In the formula, is the transient voltage stability index of the sub-region under fault ; is the weight coefficient of the 10-second transient voltage stability index, is the weight coefficient of the second-level transient voltage stability index.

[0101] After calculating all the faults in the set of pre-faults , we have:

[0102]

[0103] In the formula is the set of transient voltage stability indices of the sub-region under all faults within it.

[0104] Step 2-5-2: Screen the maximum value in it, and record the corresponding fault as the most severe fault of the sub-region ;

[0105]

[0106] Step 2-5-2: Screening the maximum value in and record the corresponding fault as the partition the most serious fault ;

[0107]

[0108] Step 3: According to the approximation of the 10-second and second-level transient voltage stability indexes under the most serious fault in the partition to the threshold value, gradually apply a certain adjustment amount to make the transient voltage stability under the most serious fault in the partition approach its critical state.

[0109] Step 3-1: Set the 10-second and second-level dynamic effective reactive power reserve state variables and , and set their initial values to 0;

[0110] Step 3-2: Perform time-domain simulation to calculate the partition the most serious fault and obtain the voltage disturbance trajectories of each node in the partition;

[0111] Step 3-3: Calculate the 10-second and second-level transient voltage stability indexes based on the voltage disturbance trajectories. For example, for the fault there are:

[0112]

[0113]

[0114] In the formula, and are the sets of 10-second and second-level transient voltage stability indexes of the binary table of each node in the partition under the fault respectively, and and are the 10-second and second-level binary table transient voltage stability indexes of the th node in the partition under the fault respectively.

[0115] Step 3-4: Screen the nodes with the most serious 10-second and second-level transient voltage dips under the most serious fault. For example, for the fault take the maximum values in and respectively, and record the nodes corresponding to the maximum values as and respectively, which are recorded as the nodes with the most serious 10-second and second-level transient voltage dips;​​​

[0116]

[0117]

[0118] Step 3 - 5: Determine the maximum value of the second - level transient voltage stability index If is less than the threshold value 1 - ( is the stability margin, 0 ≤ <1), the second - level transient voltage of the partition is stable, but not in the critical state. Set the second - level dynamic effective reactive power reserve state variable to 1; if is greater than 1, the partition cannot meet the second - level binary table, and the second - level transient voltage is unstable. Jump to Step 3 - 7; if is less than 1 and greater than the threshold value 1 - , the partition can meet the second - level binary table, and the second - level transient voltage stability is in the critical state. Jump to Step 3 - 8;

[0119] Step 3 - 6: Screen the generator / synchronous condenser that contributes the least to the second - level transient voltage stability of the partition, shut down the generator or synchronous condenser that contributes the least to the second - level transient voltage stability, and return to Step 3 - 2 after adjustment; Step 3 - 6 - 1: Output the reactive power output of each generator and synchronous condenser in the partition at 1 s after the fault is cleared, and obtain the set of reactive power outputs of generators and synchronous condensers in the partition at 1 s after the fault is cleared :

[0120]

[0121] In the formula: is the reactive power output of the th generator / synchronous condenser in the partition at 1 s after the most severe fault is cleared, and is the total number of generators and synchronous condensers in the partition .

[0122] Step 3 - 6 - 2: Calculate the reactive power increase of each generator and synchronous condenser in the partition at 1 s after the most severe fault is cleared: The reactive power increase of the

[0123] th generator / synchronous condenser in the partition at 1 s after the most severe fault is cleared : :

[0124]

[0125] In the formula:​ Pre-fault partition The steady-state reactive power output of the

[0126] nth generator / synchronous condenser. Based on the reactive power increase of each generator and synchronous condenser at 1 s after fault clearing, the set of reactive power increases of generators and synchronous condensers at 1 s after clearing the most severe fault in the partition is obtained : :

[0127]

[0128] Step 3-6-3: Screen the generator / synchronous condenser with the smallest reactive power increase at 1 s after fault clearing as the generator / synchronous condenser with the least contribution to the second-level transient voltage stability of the partition, denoted as ;

[0129]

[0130] Step 3-6-4: Shut down the generator / synchronous condenser . If is a generator, output its active power capacity , and after shutdown, it will be replaced by new energy with the same capacity

[0131] Step 3-7: Judge whether the second-level dynamic effective reactive power reserve state variable is equal to 0. If it is equal to 0, after installing a synchronous condenser at the node, return to Step 3-2; otherwise, cancel the generator or synchronous condenser shut down in Step 3-6 in the previous iteration

[0132] Step 3-8: Judge the magnitude of the maximum value of the 10-second transient voltage stability index . If is less than the threshold value 1 - , the 10-second transient voltage of the partition is stable, but it is not in a critical state. Set the 10-second dynamic effective reactive power reserve state variable to 1; if is greater than 1, the partition cannot meet the 10-second binary table, and the 10-second transient voltage is unstable. Jump to Step 3-10; if is less than 1 and greater than the threshold value 1 - , then the partition can meet the 10-second binary table, and the 10-second transient voltage stability is in a critical state. End the calculation process

[0133] Step 3-9: Screen the dynamic reactive power source with the least contribution to the 10-second transient voltage stability, reduce the reactive power capacity of the dynamic reactive power source with the least contribution to the 10-second transient voltage stability, and after adjustment, jump back to Step 3-2

[0134] Step 3-9-1: Output the reactive power outputs of each dynamic reactive power source (generator, synchronous condenser, STATCOM) in the partition at 10 s after the fault is cleared, and obtain the set of reactive power outputs of dynamic reactive power sources in the partition at 10 s after the fault is cleared :

[0135]

[0136] where: is the partition the reactive power output of the th dynamic reactive power source at 10 s after the most severe fault is cleared, is the total number of dynamic reactive power sources in the partition , including generators, synchronous condensers, and STATCOMs.

[0137] Step 3-9-2: Calculate the reactive power increase of each dynamic reactive power source at 10 s after the most severe fault is cleared in the partition. The reactive power increase of the th dynamic reactive power source at 10 s after the most severe fault is cleared in the partition is : :

[0138]

[0139] where: is the steady-state reactive power output of the th dynamic reactive power source in the partition before the fault. Based on the reactive power increase of each dynamic reactive power source at 10 s after the fault is cleared, obtain the set of reactive power increases of dynamic reactive power sources at 10 s after the most severe fault is cleared in the partition

[0140] : :

[0141]

[0142] Step 3-9-3: Screen the dynamic reactive power source with the smallest reactive power increase at 10 s after the fault is cleared as the dynamic reactive power source with the smallest contribution to the second-level transient voltage stability of the partition, denoted as ;

[0143]

[0144] Step 3-9-4: Reduce the reactive power capacity of the dynamic reactive power source .

[0145] Step 3-10: Judge whether the 10-second-level dynamic effective reactive power reserve state quantity is equal to 0. If so, then at After installing a STATCOM at the node, return to step 3-2. Otherwise, cancel the reduction of the reactive power capacity of the dynamic reactive power source in step 3-9 of the previous iteration and end the calculation process.

[0146] Step 4: Calculate the 10-second and second-level dynamic reactive power reserves after applying the adjustment amount under the most severe fault in the partition, which are the minimum required amounts of the dynamic effective reactive power reserves in the partition.

[0147] Step 4-1: Calculate the 10-second and second-level dynamic effective reactive power reserves of each dynamic reactive power source in the partition after applying the adjustment amount:

[0148] For the 10-second dynamic effective reactive power reserve of the dynamic reactive power sources (generators, synchronous condensers, STATCOMs) in the partition :

[0149]

[0150] Where: is the upper limit of the reactive power output of the th dynamic reactive power source in the partition.

[0151] For the second-level dynamic effective reactive power reserve of the generators / synchronous condensers in the partition :

[0152]

[0153] Where: is the upper limit of the reactive power output of the th generator / synchronous condenser in the partition.

[0154] Step 4-2: Calculate the electrical sensitivities of each dynamic reactive power source to the most severe node of the 10-second transient voltage dip after applying the adjustment amount. The electrical sensitivities of the dynamic reactive power source nodes in the partition to the most severe node of the 10-second transient voltage dip are:

[0155]

[0156] Where: is the voltage offset of the dynamic reactive power source node , is the voltage offset of node , is the reactive power injection change of node .

[0157] For the partition ​​Electrical sensitivity of the internal generator / phase regulator node to the most severe node of the second-level transient voltage drop :

[0158]

[0159] Where: For generator / phase regulator nodes The voltage offset, For Node The voltage offset, For Node The reactive power injection variation.

[0160] Step 4-3: Calculate the partition after applying the adjustment amount 10-second and second-level dynamic effective reactive power reserve, partition after applying adjustment 10-second dynamic effective reactive power reserve :

[0161]

[0162] Partition after applying adjustment Second-level dynamic effective reactive power reserve :

[0163]

[0164] The 10-second and second-level partition dynamic effective reactive power reserves after the adjustment amount is applied are the partition dynamic effective reactive power reserves.

[0165] In summary, the calculation method of the minimum demand for dynamic effective reactive reserve of power grid partitions in this embodiment includes setting two binary tables of 10 seconds and seconds, and constructing different node transient voltage stability indicators; for a given set of expected faults, screening the most serious faults in each partition of the power grid; according to the proximity of the 10-second and second-level transient voltage stability indicators under the most serious fault of the partition to the threshold value, applying a certain adjustment amount one by one, so that the transient voltage stability under the most serious fault of the partition approaches its critical state; calculating the 10-second and second-level dynamic reactive reserves after applying the adjustment amount under the most serious fault of the partition as the minimum demand for dynamic effective reactive reserve of the partition. The present invention constructs 10-second and second-level transient voltage stability indicators to guide the adjustment of reactive reserve, and proposes two minimum partition dynamic reactive reserve demand calculation methods of "10 seconds" and "seconds" for large power grids, which can provide support for effectively utilizing different types of reactive reserve resources of the system and improving the transient voltage stability of the large power grid.

[0166] In addition, this embodiment also provides a calculation system for the minimum required amount of dynamic effective reactive power reserve in a power grid partition, including a microprocessor and a memory connected to each other. The microprocessor is programmed or configured to execute the calculation method for the minimum required amount of dynamic effective reactive power reserve in the power grid partition. This embodiment also provides a computer-readable storage medium, in which a computer program is stored. The computer program is used to be programmed or configured by the microprocessor to execute the calculation method for the minimum required amount of dynamic effective reactive power reserve in the power grid partition.

[0167] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-readable storage media (including but not limited to disk memories, CD-ROMs, optical memories, etc.) containing computer-usable program code. The present application is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or block in the flowchart and / or block diagram can be implemented by computer program instructions, and the combination of processes and / or blocks in the flowchart and / or block diagram can also be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for realizing the functions specified in Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks. These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory generate a manufactured product including an instruction device, and the instruction device realizes the functions specified in Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks. These computer program instructions can also be loaded onto a computer or other programmable data processing device, so that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process. Therefore, the instructions executed on the computer or other programmable device provide steps for realizing the functions specified in Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0168] The above are only the preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions falling within the concept of the present invention belong to the protection scope of the present invention. It should be noted that for those of ordinary skill in the art, several improvements and refinements made without departing from the principle of the present invention should also be regarded as within the protection scope of the present invention.

Claims

1. A calculation method for the minimum required amount of dynamic effective reactive power reserve in power grid zoning, characterized in that include: Step 1: Set up a binary table and a node transient voltage stability index for the long time scale L and the short time scale S respectively. The binary table is used to define the lowest threshold value of the voltage and the longest duration that the voltage cannot exceed the specified time when it is below the threshold value at this time scale. under this time scale below this threshold value and the specified time that cannot be exceeded; Step 2: For a given set of expected faults, screen the most serious faults in each section of the power grid; Step 3: According to the proximity of the node transient voltage stability index and the threshold value at the long time scale L and the short time scale S under the most serious fault in the partition, a certain adjustment amount is applied successively to make the transient voltage stability under the most serious fault in the partition approach its critical state; Step 4: Calculate the dynamic reactive power reserves of the long time scale L and the short time scale S after applying the adjustment amount under the most serious fault in the partition as the minimum required amount of dynamic effective reactive power reserve of the partition.

2. The calculation method of the minimum required dynamic reactive power reserve for power grid zoning according to claim 1, characterized in that When setting the binary table and the node transient voltage stability index for two time scales respectively in Step 1, it includes setting the binary table for the long time scale L and setting the binary table for the short time scale S . The binary table for the long time scale L represents the longest duration when the voltage is lower than the threshold value of the long time scale L and cannot exceed the specified time of the long time scale L . The binary table for the short time scale S represents the longest durationwhen the voltage is lower than the threshold value of the short time scale S and cannot exceed the specified time of the short time scale S , and it satisfies . .

3. The calculation method for the minimum required dynamic reactive power reserve of power grid zoning according to claim 1, characterized in that, When the binary table and node transient voltage stability index are set for two time scales in step 1, the calculation function expression of the node transient voltage stability index set for the long time scale L is: In the above formula, is the fault lower node long - time scale L transient voltage stability index of the binary table; is the area of the sub - region corresponding to the binary table of the long - time scale L; is the critical area corresponding to the binary table of the long - time scale L; is the moment when the voltage is lower than the voltage threshold value of the binary table of the long - time scale L during the voltage drop process; is the moment when the voltage is higher than the voltage threshold value of the binary table of the long - time scale L during the voltage rise process, is the rated voltage; is the fault lower node actual voltage change trajectory at time t; is the voltage threshold value of the binary table of the long - time scale L; is the longest critical time for the binary table of the long - time scale L to cross the voltage threshold value; The calculation function expression of the node transient voltage stability index set by the short time scale S is: In the above formula, is the fault lower node transient voltage stability index of the binary table for the short time scale S; is the area of the sub-region corresponding to the binary table for the short time scale S; is the critical area corresponding to the binary table for the short time scale S; is the moment when the voltage drops below the voltage threshold value of the binary table for the short time scale S during the voltage drop process; is the moment when the voltage rises above the voltage threshold value of the binary table for the short time scale S, is the rated voltage; is the fault lower node actual voltage change trajectory at time t; is the voltage threshold value of the binary table for the short time scale S; is the longest critical time for the binary table for the short time scale S to cross the voltage threshold value; and when the transient voltage stability index of the node is less than 1, it means that the node under the fault can meet the requirements of the binary table for the corresponding time scale.

4. The calculation method for the minimum required dynamic reactive power reserve of power grid zoning according to claim 1, characterized in that, Step 2 includes: Step 2-1: Obtain the anticipated fault sets of each partition. For any partition the functional expression of the anticipated fault set is: In the above formula, is the expected fault set of partition , is the first fault of partition , is the -th fault of partition , is the -th fault of partition , is the total number of faults within partition . Step 2-2: Perform time domain simulation calculations for each fault in the expected fault set to obtain the voltage disturbance trajectory of the nodes in the corresponding partition under each fault; Step 2-3: According to the disturbed trajectory of node voltage in the corresponding partition under the fault, the node transient voltage stability index of the long time scale L and the short time scale S are calculated respectively, and the node transient voltage stability index set of the long time scale L and the short time scale S is obtained: In the above formula, , are respectively the sets of node transient voltage stability indices of two time scales, namely the long time scale L and the short time scale S, for the nodes in the lower partition of the fault; ~ are respectively the node transient voltage stability indices of the long time scale L for the 1st to lower partition -th nodes in the fault; is the node transient voltage stability index of the long time scale L for the lower partition -th node in the fault; ~ are respectively the node transient voltage stability indices of the short time scale S for the 1st to lower partition -th nodes in the fault; is the node transient voltage stability index of the short time scale S for the lower partition -th node in the fault; is the number of nodes in the partition; Step 2-4: Take the maximum value of the set of node transient voltage stability indices for the long time scale L and record the node corresponding to the maximum value of the long time scale L , take the maximum value of the set of node transient voltage stability indices for the short time scale S and record the node corresponding to the maximum value of the short time scale S ; Step 2-5: Calculate the transient voltage stability index of the partition according to the following formula: In the above formula, is the transient voltage stability index of the partition under fault, is the weight coefficient of the transient voltage stability index of the long time scale L, is the maximum value in the set of node transient voltage stability indexes of the long time scale L, is the weight coefficient of the transient voltage stability index of the short time scale S, is the maximum value in the set of node transient voltage stability indexes of the short time scale S; The transient voltage stability indexes of each partition are used to construct the pre-contingency fault set of all faults in : In the above formula, to are respectively the partition transient voltage stability indexes of the 1st to th faults; the maximum value is selected from the set of the pre-fault sets in the partition of all the partition transient voltage stability indexes of the faults, and the fault corresponding to the maximum value is taken as the most severe fault of the partition . .

5. The calculation method for the minimum required dynamic reactive power reserve of power grid zoning according to claim 1, characterized in that, Step 3 includes: Step 3-1: Set the dynamic effective reactive power reserve state variables for two time scales, namely the long time scale L and the short time scale S, with their initial values both set to 0. , , and their initial values are both set to 0. Step 3-2: Time-domain simulation calculation partition The most severe fault , and obtain the disturbed trajectories of the voltages of each node within the partition; Step 3-3: Calculate the transient voltage stability index of two time scales, long time scale L and short time scale S, based on the voltage disturbance trajectory: In the above formula, , are respectively the most serious faults in the lower partition of the node transient voltage stability index set of the binary table of the long time scale L and the short time scale S of the internal nodes; , are respectively the most serious fault in the lower partition of the node transient voltage stability index of the binary table of the long time scale L and the short time scale S of the th node; Step 3-4: Screen each partition according to the following formula of the most serious fault The transient voltage stability indexes corresponding to the nodes with the most serious transient voltage dips on the long time scale L and the short time scale S under the following In the above formula, and are respectively the most serious faults in the partition lower partition the maximum value of the set of node transient voltage stability indices of the binary table of the long time scale L and the short time scale S of the internal nodes, record the maximum value The corresponding node is used as the node with the most serious transient voltage drop on the long time scale L , the maximum value The corresponding node is used as the node with the most serious transient voltage drop on the short time scale S ; Step 3-5: Determine the maximum value of the short-term transient voltage stability index If the maximum value is less than the threshold value 1 - ( is the stability margin, 0 ≤ < 1), then the transient voltage of the partition in the short time scale S is stable but not in the critical state. Set the dynamic effective reactive power reserve state quantity of the short time scale S to 1; if is greater than 1, the partition cannot meet the binary table of the short time scale S, and the transient voltage of the short time scale S is unstable. Jump to Step 3-7; if the maximum value is less than 1 and greater than the threshold value 1 - , then the partition can meet the binary table of the short time scale S, and the transient voltage stability of the short time scale S is in the critical state. Jump to Step 3-8; Step 3-6: Screen the generator or phase regulator that has the smallest contribution to the transient voltage stability of the partitioned short-time scale S, shut down the generator or phase regulator that has the smallest contribution to the transient voltage stability of the short-time scale S, and return to step 3-2 after adjustment; Step 3-7: Determine the dynamic effective reactive power reserve state quantity of the short-term time scale S Is it equal to 0? If so, install a synchronous condenser or other dynamic reactive power compensation equipment at the node with the most severe transient voltage dip in the short-term time scale S, and then return to Step 3-2; otherwise, cancel the generator or synchronous condenser decommissioned in Step 3-6 in the previous iteration. Step 3-8: Determine the maximum value of the long-term transient voltage stability index If the maximum value is less than the threshold value 1 - , the transient voltage of the long-term scale L in the partition is stable but not in a critical state. Set the dynamic effective reactive power reserve state quantity of the long-term scale L to 1; if is greater than 1, the partition cannot meet the binary table of the long-term scale L, and the transient voltage of the long-term scale L is unstable; if the maximum value is less than 1 and greater than the threshold value 1 - , the partition can meet the binary table of the long-term scale L, and the transient voltage stability of the long-term scale L is in a critical state, and the calculation process ends; Step 3-9: Screen the dynamic reactive power source that contributes the least to the transient voltage stability of the long time scale L, reduce the reactive capacity of the dynamic reactive power source that contributes the least to the transient voltage stability of the long time scale L, and return to step 3-2 after adjustment; Step 3-10: Judge the dynamic effective reactive power reserve state quantity of the long time scale L Whether it is equal to 0. If so, install a dynamic reactive power compensation device such as a STATCOM at the node with the most serious transient voltage dip in the long time scale L and return to Step 3-2. Otherwise, cancel the reduction of the reactive power capacity of the dynamic reactive power source in Step 3-9 of the previous iteration and end the calculation process.

6. The calculation method for the minimum required amount of dynamic effective reactive power reserve in power grid zoning according to claim 5, characterized in that The generators or phase regulators that have the smallest contribution to the transient voltage stability of the subarea short time scale S in step 3-6 include: Step 3-6-1: Output the reactive power outputs of each generator and synchronous condenser within the partition at short-term scale S after fault removal, and obtain the set of reactive power outputs of generators and synchronous condensers within the partition at short-term scale S after fault removal : In the above formula, ~ are the reactive power outputs of the 1st to generators or synchronous condensers at the short-time scale S moment after the removal of the most serious fault in the partition, respectively, is the reactive power output of the th generator or synchronous condenser at the short-time scale S moment after the removal of the most serious fault in the partition, n and is the total number of generators and synchronous condensers in the partition . Step 3-6-2: Calculate the partition according to the following formula The reactive power increase of each generator and synchronous condenser at the short-time scale S moment after the removal of the most serious fault: In the above formula, is the partition the reactive power increase of the th generator or synchronous condenser at time scale S after the removal of the most severe fault, is the steady-state reactive power output of the th generator or synchronous condenser in the partition before the fault; according to the reactive power increase of each generator and synchronous condenser in each partition at time scale S after the removal of the most severe fault, the reactive power increase set of generators and synchronous condensers at time scale S after the removal of the most severe fault in the partition is obtained: : In the above formula, ~ are respectively the reactive power increase amounts of the 1st to th generators and synchronous condensers at the short-time scale S moment after the most serious fault in each partition is cleared; ​ Step 3-6-3: Select the generator or phase regulator with the smallest reactive power increase at the short time scale S after the fault is removed as the generator or phase regulator with the smallest contribution to the transient voltage stability of the partition short time scale S according to the following formula: In the above formula, is the generator or synchronous condenser that contributes the least to the transient voltage stability of the partition in the short time scale S.

7. The calculation method for the minimum required dynamic reactive power reserve of power grid zoning according to claim 5, characterized in that The dynamic reactive power sources that contribute the least to the transient voltage stability of the long time scale L selected in step 3-9 include: Step 3-9-1: Output the reactive power output of each dynamic reactive power source in the partition at the long-term scale L after fault excision. The dynamic reactive power sources include generators, synchronous condensers, and STATCOMs, and obtain the set of reactive power outputs of dynamic reactive power sources in the partition at the long-term scale L after fault excision : In the above formula, ~ are the partitions The reactive power output of the 1st to dynamic reactive power sources at the long-time scale L after the removal of the most severe fault, are the partitions The reactive power output of the th dynamic reactive power source at the long-time scale L after the removal of the most severe fault, is the total number of dynamic reactive power sources within the partition ; Step 3-9-2: Calculate the partition according to the following formula The reactive power increase of each dynamic reactive power source at the long-term scale L moment after the most serious fault is removed: In the above formula, is the partition The reactive power increase of the th dynamic reactive power source at the long-time scale L after the removal of the most severe fault, is the steady-state reactive power output of the th dynamic reactive power source in the partition before the fault; according to the reactive power increase of each dynamic reactive power source at the long-time scale L after the removal of the most severe fault in the partition the set of reactive power increases of dynamic reactive power sources at the long-time scale L after the removal of the most severe fault in the partition is obtained: Set of reactive power increases of dynamic reactive power sources at the long-time scale L after the removal of the most severe fault : In the above formula, ~ are respectively the reactive power increase amounts of the 1st to th dynamic reactive power sources at the long time scale L after the removal of the most serious fault; ​ Step 3-9-3: Select the dynamic reactive power source with the smallest reactive power increase at the long time scale L after the fault is removed as the dynamic reactive power source with the smallest contribution to the transient voltage stability at the short time scale S of the partition: In the above formula, is the dynamic reactive power source that contributes the least to the transient voltage stability of the partition short-time scale S.

8. The calculation method for the minimum required amount of dynamic effective reactive power reserve for power grid zoning according to claim 5, characterized in that, Step 4 includes the following process: Step 4-1: Calculate the dynamic effective reactive power reserves of each dynamic reactive power source in the partition after applying the adjustment amount for two time scales, namely the long time scale L and the short time scale S, according to the following formula: ​ In the above formula, is the long-term scale L dynamic effective reactive power reserve of the th dynamic reactive power source in the th partition, is the upper limit of the reactive power output of the th dynamic reactive power source in the th partition; Determine the partition according to the following formula Dynamic effective reactive power reserve of the short time scale S of the in - generator or synchronous condenser : In the above formula, is the upper limit of the reactive power output of the nth generator or synchronous condenser within the partition; Step 4-2: Calculate the electrical sensitivity of each dynamic reactive source to the node with the most severe transient voltage drop in the long time scale L after applying the adjustment amount according to the following formula: In the above formula, is the electrical sensitivity of the th dynamic reactive power source after applying the adjustment amount to the node with the most serious transient voltage drop on the long time scale L, is the voltage offset of the th dynamic reactive power source, is the voltage offset of the node with the most serious transient voltage drop, is the change in reactive power injection of the node with the most serious transient voltage drop; Calculate the partition according to the following formula Electrical sensitivity of the in-generator or synchronous condenser node to the node with the most severe short-term transient voltage dip on the short time scale S : In the above formula, is the voltage offset of the generator or phase modifier node , is the voltage offset of node , is the reactive power injection change of node ; Step 4-3: Calculate the partition after applying the adjustment amount The dynamic effective reactive power reserves of two time scales, namely the long time scale L and the short time scale S, where the partition after applying the adjustment amount The dynamic effective reactive power reserve of the long time scale L The calculation function expression is as follows: ， Partition after applying adjustment amount Dynamic effective reactive power reserve at short time scale S The calculation function expression is as follows: The partition after applying the adjustment amount Dynamic effective reactive power reserve at long time scale L and the partition after applying the adjustment amount Dynamic effective reactive power reserve at short time scale S Output as the minimum demand of the partition dynamic effective reactive power reserve.

9. A calculation system for the minimum required amount of dynamic effective reactive power reserve in a power grid partition, comprising a microprocessor and a memory connected to each other, characterized in that, The microprocessor is programmed or configured to execute the method for calculating the minimum demand for dynamic effective reactive power reserve of a power grid section as claimed in any one of claims 1 to 8.

10. A computer-readable storage medium storing a computer program, characterized in that, The computer program is used to be programmed or configured by a microprocessor to execute the calculation method for the minimum required amount of dynamic reactive power reserve for grid partitioning described in any one of claims 1 to 8.

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