A substation safety risk assessment method and device considering interval power outage and a storage medium

Abstract

The application discloses a substation safety risk assessment method and device considering interval power failure and a storage medium, and belongs to the technical field of relay protection and power system safety analysis. The method comprises the following steps: obtaining a historical interval fault event set causing a fault disturbance of an integrated substation system; determining a historical interval fault event with the greatest influence on the system from the historical interval fault event set based on a brainstorming algorithm; obtaining system operation data corresponding to the greatest historical interval fault event occurring in parallel during power failure of a fault interval or a reconstruction interval; calculating power failure risks and equipment risks of the remaining operation intervals in each substation according to the system operation data, and then determining overall operation risk values of each substation in the system management range based on the power failure risks and the equipment risks. The application can effectively predict the overall operation risk values of the substation corresponding to the major fault occurring again after the interval power failure reconstruction by taking the interval in the substation as a basic research unit, and has high practicability.

Description

TECHNICAL FIELD

[0001] The present application relates to a substation safety risk assessment method, device and storage medium considering interval power outage, and belongs to the technical field of relay protection and power system safety analysis. BACKGROUND

[0002] As the main undertaker in the process of power transmission, a substation not only contains a large number of expensive primary equipment, but also is equipped with various secondary equipment such as measurement, protection, control, communication and monitoring. During the operation process of the substation, partial interval power outage modification is inevitable, and during this process, due to the change of the operation mode of the substation, not only the reliability of power supply is reduced, but also the backup capability of the power grid is reduced, resulting in an increase in the operation risk of the power grid after a fault disturbance. Therefore, when an interval is under maintenance, the power department often determines the switch opening and closing process and various measures during the maintenance period, i.e., when the system is in an N-1 state, to ensure the overall safety of the power grid during operation.

[0003] However, during the power outage modification of the above interval, many unknown different fault events may occur in the remaining intervals of the integrated substation system, and when these unknown faults are superimposed on the interval being maintained, it may have a great impact on the stable operation of the system. Therefore, in view of the uncertain situation that different degrees of unknown faults may occur in other intervals, how to take preventive measures to maximize the level in advance and effectively has become a major technical problem that needs to be solved at present. SUMMARY

[0004] The purpose of the present application is to provide a substation safety risk assessment method, device and storage medium considering interval power outage, which aims to optimize the safety risk assessment of the power grid during power outage modification through an innovative method, and especially can more accurately identify high-risk areas when dealing with potential faults and adjust the monitoring strategy accordingly.

[0005] To achieve the above-mentioned purpose / in order to solve the above-mentioned technical problems, the present application is realized by adopting the following technical scheme.

[0006] On the one hand, the present application provides a substation safety risk assessment method considering interval power outage, which comprises:

[0007] obtaining a set of historical interval fault events causing a fault disturbance of an integrated substation system;

[0008] determining, based on a brainstorming optimization algorithm, a historical interval fault event having the greatest impact on the integrated substation system from the set of historical interval fault events;

[0009] Obtain system operation data corresponding to the historical interval fault events that have the greatest impact on the integrated substation system when known fault intervals or modified intervals occur in parallel during power outages;

[0010] Based on the system operation data, the power outage risk and equipment risk of each other operating interval in each substation are calculated. Then, based on the power outage risk and equipment risk of each other operating interval in each substation, the overall operation risk value of each substation within the system management scope is determined.

[0011] This invention comprehensively considers the operational data of an integrated substation system under secondary bay fault conditions, combines a brainstorming optimization algorithm to screen fault events, and ultimately generates a strategy table to guide renovation or maintenance. This safety risk assessment method helps improve the safety and reliability of substation systems and reduces the potential risks caused by secondary major fault events that may occur during bay renovation.

[0012] Optionally, the power outage risks of the remaining operating bays within each substation include: the first power outage risk corresponding to the power outage of the operating bay caused by a known faulty bay or a modified bay within the substation during a power outage, and the second power outage risk corresponding to the power outage of the upstream circuit breaker bay caused by the failure of the circuit breaker of the operating bay to disconnect power under fault.

[0013] Optionally, the formula for calculating the first power outage risk is expressed as follows:

[0014]

[0015] In the formula, This indicates that a known faulty or modified section within the substation causes the operating section to be affected during a power outage. The first risk associated with a power outage is... Indicates the running interval The outgoing line load factor, This indicates the price per kilowatt-hour of electricity. Indicates the interval during which power has been cut off for maintenance. Intervals of planned power outages and simulated secondary faults After a malfunction occurs, the operating interval The probability of a power outage due to a fault. Indicates interval The time of the power outage Indicates the running interval Experience with power outage recovery time Indicates the running interval exist arrive Transmission power over a given time period.

[0016] Optionally, the formula for calculating the second power outage risk is as follows:

[0017]

[0018] in the formula, indicates the running interval of the circuit breaker corresponding to the second power failure risk caused by the failure of power failure under fault to stop the power of the upper level circuit breaker interval, indicates the accident rate of the circuit breaker transformer according to the working time, indicates the interval of power failure, indicates the interval of power failure recovery expected time, indicates the running interval of the upper level power failure range power failure time period predicted by the power curve, indicates the running interval of the circuit breaker.

[0019] Optionally, if the load carried by the outgoing line is only supplied by the running interval , the outgoing line load coefficient of the running interval is 1; if the load carried by the outgoing line is supplied by multiple intervals, the outgoing line load coefficient of the running interval is 0.

[0020] Optionally, the device risk of each remaining running interval in each substation is calculated by the following formula:

[0021]

[0022] in the formula, indicates the device risk of the running interval , and indicates the overall primary equipment cost of the running interval .

[0023] Optionally, based on the power failure risk and the device risk of each remaining running interval in each substation, the overall running risk of each substation in the system management range is determined, including:

[0024] The overall running risk value of each running interval is calculated according to the power failure risk and the device risk of each running interval;

[0025] The initial overall running risk value of each substation is determined by considering the overall running risk value of all running intervals in each substation and the overall running risk value of the directly connected interval adjacent to each substation;

[0026] The preset risk value corresponding to the same level of each substation in the system management range is obtained, and the preset risk value is taken as the risk reference value corresponding to each substation;

[0027] According to the initial overall operation risk value of each substation and the risk reference value corresponding to each substation, a risk degree unit value corresponding to each substation is calculated, and the risk degree unit value is taken as the overall operation risk value of each substation.

[0028] Optionally, according to the power failure risk and the equipment risk of each operation interval, an overall operation risk value of each operation interval is calculated, which is represented as:

[0029]

[0030] In the formula, R represents the overall operation risk value of the operation interval, respectively, and satisfy .

[0031] Optionally, considering the overall operation risk values of all operation intervals in each substation and the overall operation risk values of directly connected intervals of adjacent substations of each substation, an initial overall operation risk value of each substation is determined, which is represented as:

[0032]

[0033] In the formula, R represents the initial overall operation risk value of each substation,

[0034] Optionally, considering the substation with interval power failure, according to the initial overall operation risk value of each substation and the risk reference value corresponding to each substation, a risk degree unit value corresponding to each substation is calculated, which is represented as:

[0035]

[0036] In the formula, R represents the risk degree unit value corresponding to each substation,

[0037] Optionally, based on a brainstorm optimization algorithm, a historical interval fault event with the greatest influence on the integrated substation system is determined from the set of historical interval fault events, including:

[0038] Based on the set of historical interval fault events, an initial population is generated and algorithm parameters are set;

[0039] ​​​​​​​​The initial population is clustered by using a k-means clustering algorithm, and then, in each class, the individuals contained therein are sorted according to the fitness value, and the individual with the largest fitness value is selected as the cluster center of the class;

[0040] Based on the brainstorming algorithm, a random number is generated, and the value of the random number is used to determine the corresponding operation type; if the random number is less than or equal to a first threshold value, the operation of selecting a random individual is performed, and a new individual is generated by adding random disturbance; if the random number is between the first threshold value and a second threshold value, the operation of selecting a cluster center or a random individual is performed, and a new individual is generated by adding random disturbance; if the random number is greater than or equal to the second threshold value, the operation of selecting two cluster centers or random individuals is performed, the two individuals or cluster centers are fused, and a new individual is generated by adding random disturbance;

[0041] The new individual is compared with the cluster center by taking the risk degree unit value as the fitness value, and the individual with a high fitness value is selected to enter the next generation;

[0042] The clustering, individual updating, and selection operations are repeated until a preset iteration number is reached, and after the iteration ends, the optimal solution corresponding to the interval fault event that has the greatest impact on the integrated substation system is output.

[0043] Optionally, according to the risk degree unit value corresponding to each substation, the scanning interval time of the corresponding operation data is arranged, including:

[0044] If the risk degree unit value of the substation is within a preset first risk range, the scanning interval of the corresponding operation data is set to one hour; if the risk degree unit value of the substation is within a preset second risk range, the scanning interval of the corresponding operation data is set to half an hour; if the risk degree unit value of the substation is within a preset third risk range, the scanning interval of the corresponding operation data is set to ten minutes; and if the risk degree unit value of the substation is within a preset fourth risk range, the scanning interval of the corresponding operation data is set to five minutes.

[0045] In a second aspect, the present application also provides a substation safety risk assessment device considering interval outage, which comprises:

[0046] A historical interval fault acquisition module is configured to acquire a set of historical interval fault events causing a fault disturbance of an integrated substation system;

[0047] A secondary fault interval determination module is configured to determine, based on a brainstorming optimization algorithm, a historical interval fault event that has the greatest impact on the integrated substation system from the set of historical interval fault events;

[0048] The operation data acquisition module is configured to acquire system operation data corresponding to a historical interval fault event that has the greatest impact on the integrated substation system when a known fault interval or a modification interval occurs in parallel during power failure;

[0049] The substation risk assessment module is configured to calculate power failure risks and equipment risks of each operation interval in each substation according to the system operation data, and determine overall operation risk values of each substation in the system management range based on the power failure risks and the equipment risks of each operation interval in each substation.

[0050] In a third aspect, the present application further provides a computer readable storage medium having a computer program stored thereon, and the computer program is executed by a processor to implement the steps of the substation safety risk assessment method considering interval power failure.

[0051] Compared with the prior art, the present application has the following beneficial effects:

[0052] Firstly, the present application uses the brainstorming algorithm to screen the optimal solution from the intervals that may fail again in combination with the actual situation during power failure modification of the power grid, and then innovatively constructs a relay protection safety risk assessment model taking the interval as the core to perform power failure risk assessment and equipment risk assessment of the operation interval based on the high-risk intervals identified by the brainstorming algorithm, so as to realize accurate assessment of the safety risks of each substation in the power grid during power failure modification, effectively prevent the occurrence of power grid failure, and improve the safety and stability of the power grid. BRIEF DESCRIPTION OF DRAWINGS

[0053] Figure 1 Fig. 1 shows a flowchart of an embodiment of the substation safety risk assessment method considering interval power failure of the present application;

[0054] Figure 2 Fig. 2 shows a flowchart of the brainstorming optimization algorithm in the substation safety risk assessment method considering interval power failure of the present application;

[0055] Figure 3A flowchart of interval-station-system risk value calculation in the substation safety risk assessment method considering interval outage of the application is shown.

[0056] Figure 4 A flowchart of another embodiment of the substation safety risk assessment method considering interval outage of the application is shown. DETAILED DESCRIPTION

[0057] The technical solutions of the application will be described in detail below with reference to the drawings and specific embodiments, and it should be understood that the embodiments and specific features in the embodiments are detailed descriptions of the technical solutions of the application, and are not limitations of the technical solutions of the application, and the technical features in the embodiments and the embodiments can be combined with each other without conflict.

[0058] The term "and / or", only describes the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent three cases of A alone, A and B together, and B alone. In addition, the character " / ", generally represents that the front and rear associated objects are a "or" relationship.

[0059] Embodiment 1

[0060] Reference Figure 1 The embodiment introduces a substation safety risk assessment method considering interval outage, which includes:

[0061] Obtain a set of historical interval fault events causing fault disturbance of the integrated substation system;

[0062] Based on the brainstorming optimization algorithm, the historical interval fault event with the greatest impact on the integrated substation system is determined from the set of historical interval fault events;

[0063] Obtain the system operation data corresponding to the historical interval fault event with the greatest impact on the integrated substation system when the known fault interval or the modified interval occurs during the outage period in parallel;

[0064] According to the system operation data, the outage risk and equipment risk of each operation interval in each substation are calculated, and then based on the outage risk and equipment risk of each operation interval in each substation, the overall operation risk value of each substation in the system management range is determined.

[0065] In the actual application process of the embodiment, first, the interval fault event set causing the integrated substation system to have a fault disturbance is extracted from a historical database. Based on the above interval fault event set, the historical fault event set is analyzed by using a BrainStorm Optimization (BSO) algorithm to determine the interval fault event that has the greatest impact on the system. At the same time, the system operating state corresponding to the interval fault event that has the greatest impact on the system and occurs in parallel under the primary interval fault state is set as the secondary interval fault state.

[0066] After the secondary interval fault state is confirmed, a data collection system is started to capture various operating data in real time under the state, and the collected operating data under the secondary interval fault state are input into a relay protection safety risk assessment model with an interval as a minimum consideration unit to calculate the overall operating risk value of each substation in the system management range. The risk value should be able to reflect the comprehensive performance of the system in terms of stability, reliability, and safety under the secondary interval fault state.

[0067] Embodiment 2

[0068] Reference Figures 1 to 3 On the basis of embodiment 1, the embodiment will introduce in detail the specific implementation process of the safety risk assessment of each substation under consideration of double interval fault disturbances.

[0069] I. Construction of a substation safety risk assessment model with an interval as a core

[0070] In view of the operating characteristics of a substation, the embodiment takes an interval in the substation as a basic research unit to evaluate the unknown safety risk brought by the possible further deterioration of the power grid operating mode (N-1-n, secondary interval fault state) after the power-off reconstruction of a certain interval (N-1, primary interval fault state). The unknown safety risk corresponds to the risk evaluation of the system risk brought by the equipment (N-1-n) that is possibly forced to exit after N-1. The forced exit of the equipment after N-1 is often caused by a fault or abnormal operation, and the adverse impact on the system is greater after the exit, and the power grid operating mode will change significantly in the process. Therefore, it is necessary to establish a related evaluation model to accurately estimate the unknown risk value brought by the power-off reconstruction.

[0071] For the selection of the target risk value prediction model, the embodiment forms a structure network of interval-station-system by constructing a relay protection safety risk assessment model taking interval as the minimum consideration unit. In actual application, the relay protection safety risk assessment model mainly needs to consider the outage risk (power supply outage loss) of the substation interval and the equipment risk (expected equipment damage). The outage risk can be expressed by using the electricity price table, and the equipment risk can be expressed by using the state of the near and far backup and whether the backup protection is missing, which causes the possibility of equipment damage risk.

[0072] Reference Figure 3 Based on the above outage risk and equipment risk, the risk of each interval, the whole and the remaining substations of the current substation can be determined, and then a strategy table is formed for different risk values of each substation, so that the risk value can be calculated online when facing the corresponding situation, and the corresponding strategy can be taken in time to reduce the risk value of the related substation.

[0073] II. Based on the brainstorming algorithm, determine the fault solution corresponding to the maximum impact on the system under the condition of the current primary interval fault state

[0074] First of all, it is worth mentioning that when one of the intervals is under maintenance, the power department will often have taken various measures in advance, determined the switch opening and closing process and various operating measures during the maintenance period, i.e. the system is in N-1 state, so there is no need to further evaluate the risk under this state. However, during this period, many different fault events may occur in the remaining intervals, which may have a great impact on the stable operation of the system when these faults are superimposed on the maintenance interval. Therefore, the fault with the greatest impact needs to be found, and the overall risk of the related substations is evaluated under the condition of this fault, so that the power department can take measures in advance or develop a corresponding strategy table for the substations with high risk under this condition to avoid being unable to solve the high-risk situation that the substations may face when the fault actually occurs.

[0075] To know which fault event, i.e. the system is in which N-1-n state, is the most affected, the simplest method is to exhaust n, and then calculate each case using the above-mentioned relay protection safety risk assessment model to obtain the worst evaluation value under which N-1-n condition, but this method is extremely time-consuming and not suitable for use. If random guess sorting is used, it is easy to fall into local optimal solution and cannot find the global optimal solution. Therefore, the brainstorming algorithm is used to find the fault solution with the greatest impact on the system in this embodiment, so as to quickly and reliably jump out of the local optimal solution and find the global optimal solution.

[0076] In addition, the operation control of the current power system is quite complete, and the static and dynamic safety control of the system is relatively reliable, so N-1-1 or N-1-2 is a relatively common situation, otherwise the system may enter the splitting state, and the existing power system has corresponding control and recovery measures for the splitting state. Reference Figure 2 The embodiment is only used for example analysis of the N-1-1 state.

[0077] Specifically, the historical interval fault event set causing the integrated substation system to have a fault disturbance is acquired.

[0078] Further, the algorithm is used to determine the interval fault event with the greatest impact on the integrated substation system from the historical interval fault event set, that is, the interval fault event simulated to occur in the subsequent risk assessment application process In the embodiment, the interval is obtained by a brainstorming optimization algorithm, and the related algorithm pseudo code is as follows:

[0079] 1. Based on the historical interval fault event set, initialize the population size N and the maximum iteration number T. Wherein, N = dimension x margin, the margin represents the operation mode of the system, such as the maximum operation mode, the minimum operation mode, etc.; the dimension dim represents the number of elements that may be lost or faults that may occur; and the maximum iteration number T represents the number of times of excitation in each cycle. For example, if there are one hundred operation modes and only one element is considered to be lost, there are one hundred populations; if there are one hundred operation modes and two elements are considered to be lost, there are two hundred populations.

[0080] 2. Initialize parameters and population Xm, wherein m = 1, 2, …, N. For example, only one element is considered to be lost, at this time the dimension is equal to 1 and the margin is equal to 2, so X1 is the target value under the large operation mode and X2 is the target value under the small operation mode.

[0081] 3. While q < Q, do. Wherein, q represents the number of cycles.

[0082] 3.1, using k-means clustering algorithm to cluster N individuals into K clusters. Roughly assign different components or failures and different operating modes, such as assigning a generator failure to 100*generator rated power, and assigning the maximum operating mode to 2, then the maximum operating mode of a certain generator component loss event can be assigned to 2*100*generator rated power. Assign a quick value to each individual in this way to facilitate k-means clustering; randomly select K data points as initial cluster centers; distribute the remaining fault events to the nearest initial cluster center by calculating the distance from each initial cluster center, form the corresponding cluster; calculate the new centroid of each cluster, which is usually the mean of all points in the cluster, complete the update of the cluster center; repeat the distribution and update steps until the cluster center no longer changes significantly or the preset number of iterations is reached. For the case of a large number of populations, clustering into 3-5 categories is more appropriate.

[0083] 3.2, based on the brainstorming algorithm, generate a random number, and determine the corresponding operation type according to the value of the random number; if the random number is less than or equal to the first threshold value 0.2, find a random individual within this cluster range, and generate a new individual by adding random disturbance; if the random number is between the first threshold value 0.2 and the second threshold value 0.8, select the center of a cluster or a random individual, and generate a new individual by adding random disturbance; if the random number is greater than or equal to the second threshold value 0.8, select two cluster centers or random individuals, fuse the two individuals or cluster centers, and generate a new individual by adding random disturbance.

[0084] Specifically, the new individual is generated by adding random disturbance to the center or ordinary individual of one or more clusters. When a new individual is generated by selecting a cluster, the formula is as follows:

[0085]

[0086] In the formula, represents the new idea generated, represents the original idea, represents the current iteration number, represents a random number between 0 and 1, represents a coefficient for weighting the contribution of the random value to the new individual;

[0087] wherein, The calculation formula of is as follows:

[0088]

[0089] In the formula, represents a transfer function, represents the maximum number of iterations, represents the control of the slope.

[0090] When two clusters are selected to generate a new individual, the formula is as follows:

[0091]

[0092]

[0093] wherein, represents the weighted sum and , represents a randomly generated coefficient between 0 and 1, and represents the ideas selected from the two clusters, respectively.

[0094] 3.3, taking the risk value as the fitness value, comparing the new individual mentioned above with the determined cluster center, and updating and replacing the new cluster center with the high fitness. The fitness value is the risk value of the system under the event corresponding to the selected individual, which is obtained by the state estimation of the target risk value model. That is, if the fitness of the new individual is higher, that is, the system risk is greater, it can be used to replace the new cluster center. In the process, the newly generated individual is compared with the existing cluster center, and the individual with greater loss value (more serious fault event) is retained until the number of times is limited, and the final solution is output. The event corresponding to the solution is the event with the greatest impact on the system found by the brainstorming algorithm. Compared with the exhaustive method, the system risk value of each event does not need to be calculated, reducing the required time. Compared with completely random enumeration, the probability of jumping out of the local optimal solution and reaching the global optimal solution is increased.

[0095] Three, the evaluation application process of the overall operation risk value of each substation and the development of the related strategy table

[0096] In the actual risk assessment application process, the relevant operation data of the integrated substation system under the secondary interval fault state is first obtained, and the secondary interval fault state mentioned here is the operation state corresponding to the interval fault event with the greatest impact on the integrated substation system when the system is in a primary interval fault state. Further, the relevant operation data is input into the relay protection safety risk assessment model with interval as the minimum consideration unit for risk assessment, and the overall operation risk value of each substation within the system management range can be obtained, and then the corresponding strategy table can be generated according to the overall operation risk value of each substation. The related implementation process is described as follows.

[0097] First, the safety risk of the operation interval is modeled to obtain The main consideration is the risk of power outages in this interval. and equipment risks The power outage risk for each interval is determined by the interval itself. The impact on the electricity price of the output electricity during this period of normal operation is calculated.

[0098] Among them, the risk of power outage in each of the remaining operating bays within each substation. This includes: the first power outage risk corresponding to the power outage of the operating bay caused by a known faulty bay or a modified bay within the substation during a power outage. And the secondary power outage risk corresponding to the failure of a circuit breaker in the operating interval to disconnect power under fault conditions, resulting in a power outage of the upstream circuit breaker interval. .

[0099] Set interval These are the intervals that have already been shut down for maintenance. To simulate the intervals in which a fault occurs, the interval This is the interval for calculating the current risk value. Then, the first power outage risk corresponding to the power outage of the operating interval caused by a known fault interval or modification interval during a power outage is calculated using the following formula. That is, after the system experiences another fault in a state of interval fault N-1, the operating interval... The risk of power outage due to faults is represented as:

[0100]

[0101] In the formula, Indicates the running interval The outgoing line load factor, where if the outgoing line load is only supplied by the operating interval. Power supply, then operating interval The outgoing line load factor is 1. If the load on the outgoing line is supplied by multiple bays, then the operating bay... The outgoing line load factor is 0; This indicates the price per kilowatt-hour of electricity; Indicates the interval during which power has been cut off for maintenance. Intervals of planned power outages and simulated secondary faults After a malfunction occurs, the operating interval The probability of a power outage can be obtained from engineering experience; however, since the timing of a fault is uncontrollable and unpredictable, for ease of calculation, The value of is made The point in time when it reaches its maximum; Indicates the running interval Experience with power outage recovery time; Indicates the running interval exist arrive the transmission power in the time period.

[0102] In addition, when the circuit breaker of the operating interval fails, it may not be able to reliably disconnect, so the possibility of the upper-level circuit breaker interval not being able to reliably remove the fault needs to be considered. At this time, the power outage range expands, causing a power outage risk, i.e., a second power outage risk that the upper-level circuit breaker interval is powered off due to the failure of the operating interval circuit breaker to disconnect under fault.

[0103]

[0104] In the formula, is the failure rate of the circuit breaker transformer with working time according to engineering experience, take the maximum value when operating normally, the interval power outage recovery expected time, the operating interval the power predicted by the power curve in the power outage time period of the upper-level power outage range, the operating interval the working time of the circuit breaker. According to the first power outage risk

[0105] that the operating interval is powered off during the power outage period due to the known fault interval or the modification interval in the substation, and the second power outage risk that the upper-level circuit breaker interval is powered off due to the failure of the operating interval circuit breaker to disconnect under fault, the power outage risk of each operating interval can be finally calculated, which is unitized to money and expressed as:

[0106]

[0107] In the formula, and respectively represent the total incoming line power of the substation as a whole in the corresponding time period.

[0108] When the operating interval fails, various situations such as overcurrent and overvoltage may occur, especially the circuit breaker, transformer and other equipment will be subjected to a relatively high impact, and the possibility of damage is relatively high, and the failure of these two devices will cause a greater risk to the system operation. Therefore, according to the failure rate of the circuit breaker transformer with working time and whether there is backup protection, the equipment risk of the operating interval is calculated​ , the corresponding calculation formula is represented as:

[0109]

[0110] In the formula, represents the risk of the equipment in the operation interval , and represents the risk of the operation interval The overall primary equipment cost.

[0111] According to the power failure risk and the equipment risk of each operation interval, the overall operation risk value of each operation interval is calculated, which is represented as:

[0112] In the formula, represents the corresponding overall risk value of the operation interval , and and respectively represent the coefficients, and satisfy .

[0113] Further, by comprehensively considering the overall operation risk value of each operation interval of the current substation and the overall operation risk value of the directly connected interval of the adjacent station of the substation, the initial overall operation risk value of the current substation is calculated, and then the initial overall operation risk value of each substation in the system is added to obtain the corresponding risk value of the entire system , which can be used as the state estimation of the system in the secondary interval fault state N-1-n. The calculation formula of the initial overall operation risk value of the current substation is represented as:

[0114]

[0115] In the formula, represents the initial overall operation risk value of the current substation, represents the number of operation intervals in the substation, represents the overall operation risk value of the directly connected interval of the adjacent station.

[0116] It is worth noting that the data obtained above is a named value, but the power and equipment cost of different level substations are not the same, so the It is inconvenient to directly determine the risk of all substations on one chart. Therefore, an expert can select a risk value of a substation with moderate risk in the same level of substations in the management range as a reference value, and then calculate a corresponding risk degree unit value according to the initial risk value of the overall operation of the current substation and the risk reference value, and take the risk degree unit value as the overall operation risk value of the current substation. Specifically, the calculation formula of the risk degree unit value of the overall operation of the current substation is represented as:

[0117]

[0118] In the formula, the risk degree unit value of the overall operation of the current substation, the risk reference value selected by the expert in the same level of substations.

[0119] Similarly, the overall operation risk values of each substation can be determined in succession. In the actual application process, the main station can display the risk degree unit values of each substation under the current working condition. That is, whenever a substation has an interval for maintenance or other work, the main station can scan and calculate the risk values of each substation in the management range through the above method.

[0120] Further, after determining the risk degree unit values of each substation in the management range, the operation strategy and mode of each substation can be determined according to the risk degree unit value of each substation, and a strategy table can be formed to facilitate the comparison of the strategy table and the online measures. For example, if the risk value of a substation under the current maintenance state is too high, the maintenance can be stopped directly to restore power supply or the operation mode can be changed. Through the advance discussion of experts, different pre-set measures can be taken for different risk values of different substations to be placed in the system, so that the system can quickly take correct measures to solve the problem. If the risk degree unit value of a substation is less than 1, the dispatcher can be reminded to arrange single-interval maintenance and modification projects at any time. If the risk degree unit value of a substation is not less than 1, the dispatcher is reminded to take certain measures to reduce the risk value before performing modification, maintenance, etc. If the risk degree unit value during modification is greater than 1.5, the dispatcher needs to be reminded to pay attention and take certain measures to reduce the risk value, such as stopping modification as soon as possible or using other power sources to reduce the load of the substation. If the risk degree unit value of a substation during normal operation is greater than 2, the dispatcher needs to pay close attention and take corresponding measures to reduce the risk value as soon as possible.

[0121] Embodiment 3

[0122] With reference to Figure 4 On the basis of Embodiment 2, the present embodiment has the following design.

[0123] Although the time for calculating the risk value in Embodiment 2 is greatly shortened compared with the exhaustive method, if the site requires all to be in a 5-minute cycle, the above algorithm may not meet the requirement of online evaluation when there are more substations, more intervals and more possible faults, because the calculation content is too much and the time is too long.

[0124] Therefore, in the present embodiment, each substation is processed by stratification and classification according to the risk degree unit value of each substation after state estimation. For the substation with a lower risk value, i.e. the risk degree unit value of the substation is within the preset first-level risk range, the data thereof can be scanned and calculated once per hour, and the original data can be kept unchanged during the rest of the time; for the substation with a moderate risk value, i.e. the risk degree unit value of the substation is within the preset second-level risk range, the data thereof can be scanned and calculated once per half hour; for the substation with a larger risk value, i.e. the risk degree unit value of the substation is within the preset third-level risk range, the data thereof can be scanned and calculated once per ten minutes; for the substation with a larger risk value, i.e. the risk degree unit value of the substation is within the preset third-level risk range, the data thereof can be scanned and calculated once per five minutes.

[0125] When the system operating condition changes, the brainstorming algorithm is immediately performed again to find the fault that has the greatest impact under the current operating condition, and all sites and intervals are re-assigned, the new risk value is updated, and it is determined whether it needs to be focused on.

[0126] In addition, in the actual application process, the scanning times of the above several types of substations corresponding to different risk values should be staggered to ensure that the system has enough computing power at all times to perform online risk evaluation at a faster speed, so that the data can be circulated online, the data source is reliable and simple, and the result is clear.

[0127] In actual application, when the status of some interval of some substation changes due to fault, maintenance, etc., the substation is regarded as N-1 status (i.e. the initial one-interval fault status) regardless of how many intervals are actually shut down; then the brainstorming algorithm is used to find out the fault that has the greatest impact on the system after comprehensively considering the possibility and harmfulness of the fault under the current condition, and the fault is regarded as N-1-n status (n can be 1 or 2, and n is preferably set to 1 in this embodiment), and the risk values of the substations under the status are calculated, so as to find out several substations with high risk values under the status, and the strategy table of the substations and corresponding intervals is formulated in advance. Finally, the online function is considered, and the update time of the data is reasonably allocated, so as to ensure that the online safety evaluation can be realized. By combining the above processes, the online safety risk evaluation of the power system within the jurisdiction can be performed, which not only effectively improves the efficiency of system construction and operation, but also greatly enhances the applicability of the system.

[0128] Embodiment 4

[0129] Based on the same inventive concept as Embodiment 1 or 2 or 3, this embodiment introduces a substation safety risk assessment device considering interval outage, which comprises:

[0130] A historical interval fault acquisition module configured to acquire a set of historical interval fault events causing a fault disturbance of the integrated substation system;

[0131] A secondary fault interval determination module configured to determine, based on a brainstorming optimization algorithm, a historical interval fault event having the greatest impact on the integrated substation system from the set of historical interval fault events;

[0132] An operation data acquisition module configured to acquire system operation data corresponding to the historical interval fault event having the greatest impact on the integrated substation system when the known fault interval or the modified interval occurs in parallel during the outage period;

[0133] And a substation risk assessment module configured to calculate the outage risk and equipment risk of each remaining operating interval in each substation according to the system operation data, and further determine the overall operating risk value of each substation within the system management range based on the outage risk and equipment risk of each remaining operating interval in each substation.

[0134] In combination Figures 1 to 4 The substation safety risk assessment device considering interval outage can perform the substation safety risk assessment method considering interval outage introduced in Embodiment 1 or 2 or 3, and the specific function implementation of each functional module is not described herein.

[0135] Embodiment 5

[0136] The embodiment introduces a computer readable storage medium, which stores a computer program. The computer program is executed by a processor to implement the steps of the substation safety risk assessment method considering interval power outage as described in embodiment 1 or 2 or 3.

[0137] 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 an entirely hardware embodiment, an entirely 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-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0138] The present application is described with reference to flowcharts and / or block diagrams of the method, device (system) and computer program product according to the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of the flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate a means for implementing the functions specified in the flowcharts and / or block diagrams. Figure 1 one or more flows and / or blocks Figure 1 means for carrying out the functions specified in one or more blocks.

[0139] These computer program instructions can also be stored in a computer readable memory capable of directing the computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce a product including instruction means, which implements the functions specified in the flowcharts and / or block diagrams. Figure 1 one or more flows and / or blocks Figure 1 one or more blocks.

[0140] These computer program instructions can also be loaded into a computer or other programmable data processing device, so that a series of operation steps are performed on the computer or other programmable device to produce a computer implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in the flowcharts and / or block diagrams. Figure 1 one or more flows and / or blocks Figure 1 one or more blocks.

[0141] The above merely describes the preferred embodiments of the present application, and it should be pointed out that, for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present application, and these improvements and modifications should also be considered as the protection scope of the present application.

Claims

1. A substation safety risk assessment method considering interval power outage, characterized in that, The method comprises the following steps: acquiring a historical interval fault event set causing a fault disturbance of an integrated substation system; determining, based on a brainstorming optimization algorithm, a historical interval fault event with the greatest impact on the integrated substation system from the historical interval fault event set; acquiring system operation data corresponding to the historical interval fault event with the greatest impact on the integrated substation system when a known fault interval or a reconstruction interval occurs during a power outage; calculating outage risks and equipment risks of the remaining operation intervals in each substation according to the system operation data, and then determining overall operation risk values of each substation within a system management range based on the outage risks and the equipment risks of the remaining operation intervals in each substation; the outage risks of the remaining operation intervals in each substation comprise a first outage risk corresponding to an outage of an operation interval caused by a known fault interval or a reconstruction interval in a substation during a power outage, and a second outage risk corresponding to an outage of an upper-level circuit breaker interval caused by a failure of a circuit breaker in the operation interval under a fault; a calculation formula of the first outage risk is represented as: ； wherein represents the operation interval caused by the known fault interval or the modification interval in the substation during the outage the first outage risk corresponding to the outage, represents the operation interval the outgoing load factor of the operation interval, represents the electricity price per kilowatt-hour, represents the interval that has been out of service for maintenance the interval that is scheduled to be out of service and simulates a secondary fault the operation interval after a fault occurs the probability of a fault outage, represents the operation interval the time point of the outage, represents the operation interval the outage recovery experience time, represents the operation interval in the transmission power in the time period the time period a calculation formula of the second outage risk is represented as: ； In the formula, Indicates the running interval The second power outage risk corresponding to the failure of a circuit breaker to cut off power under fault conditions, resulting in the power outage of the upstream circuit breaker interval. This indicates the failure rate of the circuit breaker transformer over operating time. Indicates interval The time of the power outage Indicates interval Estimated time for power outage restoration Indicates the running interval The power predicted from the power curve during the outage period within the scope of the next higher level of power outage. Indicates the running interval The operating time of the circuit breaker; the equipment risks of the remaining operation intervals in each substation are calculated by the following formula: ； wherein the equipment risk of the operating interval the equipment risk of the operating interval the overall primary equipment cost.​ 2. The substation safety risk assessment method considering interval power outage according to claim 1, characterized in that, If the load carried by the outgoing line is only from the operating interval , then the outgoing line load factor of the operating interval is 1; If the load supplied by the outgoing line is powered by multiple bays, then the operating bay... The outgoing line load factor is 0.

3. The substation safety risk assessment method considering interval power outage according to claim 1, characterized in that, determining overall operation risk values of each substation within a system management range based on the outage risks and the equipment risks of the remaining operation intervals in each substation comprises: calculating overall operation risk values of each operation interval according to the outage risks and the equipment risks of the operation interval; considering the overall operation risk values of all operation intervals in each substation and the overall operation risk values of directly connected intervals adjacent to each substation, determining initial overall operation risk values of each substation; acquiring preset risk values corresponding to the same level of each substation within the system management range, and taking the preset risk values as risk reference values corresponding to each substation; calculating risk degree unit values corresponding to each substation according to the initial overall operation risk values of each substation and the risk reference values corresponding to each substation, and taking the risk degree unit values as the overall operation risk values of each substation.

4. The substation safety risk assessment method considering interval outages according to claim 3, characterized in that, calculating overall operation risk values of each operation interval according to the outage risks and the equipment risks of the operation interval is represented as: ； wherein represents the overall operational risk value corresponding to the operational interval, represents the outage risk of the operational interval, and respectively represent coefficients, and satisfy ; considering the overall operation risk values of all operation intervals in each substation and the overall operation risk values of directly connected intervals adjacent to each substation, determining initial overall operation risk values of each substation is represented as: ； wherein represents the initial overall operational risk value of each substation, represents the number of operational bays within a substation, represents the overall operational risk value of directly connected bays of adjacent substations; considering the substation with an interval outage, calculating risk degree unit values corresponding to each substation according to the initial overall operation risk values of each substation and the risk reference values corresponding to each substation is represented as: ； In the formula, represents the risk degree unit value corresponding to each substation, represents the risk reference value selected by the expert in the same grade substation.

5. The substation safety risk assessment method considering interval power outage according to claim 4, characterized in that, determining, based on a brainstorming optimization algorithm, a historical interval fault event with the greatest impact on the integrated substation system from the historical interval fault event set comprises: generating an initial population and setting algorithm parameters based on the historical interval fault event set; The initial population is clustered by using a k-means clustering algorithm, and then, in each class, the individuals contained therein are sorted according to the size of the fitness value, and the individual with the largest fitness value is selected as the cluster center of the class; Based on the brainstorming algorithm, a random number is generated, and the value of the random number is used to determine the corresponding operation type; if the random number is less than or equal to a first threshold value, the operation of selecting a random individual is performed, and a new individual is generated by adding random disturbance; if the random number is between the first threshold value and a second threshold value, the operation of selecting a cluster center or a random individual is performed, and a new individual is generated by adding random disturbance; if the random number is greater than or equal to the second threshold value, the operation of selecting two cluster centers or random individuals is performed, the two individuals or cluster centers are fused, and a new individual is generated by adding random disturbance; The new individual is compared with the cluster center by taking the risk degree unit value as the fitness value, and the individual with a higher fitness value is selected to enter the next generation; The clustering, individual updating, and selection operations are repeated until a preset iteration number is reached, and after the iteration ends, the optimal solution corresponding to the interval fault event that has the greatest impact on the integrated substation system is output.

6. The substation safety risk assessment method considering interval outages according to claim 5, characterized in that, According to the risk degree unit value of each substation, the scanning interval time of the corresponding operation data is arranged, including: If the risk degree unit value of the substation is within a preset first risk range, the scanning interval of the corresponding operation data is set to one hour; if the risk degree unit value of the substation is within a preset second risk range, the scanning interval of the corresponding operation data is set to half an hour; if the risk degree unit value of the substation is within a preset third risk range, the scanning interval of the corresponding operation data is set to ten minutes; and if the risk degree unit value of the substation is within a preset fourth risk range, the scanning interval of the corresponding operation data is set to five minutes.

7. A substation safety risk assessment device considering interval power outage, characterized by, It includes: A historical interval fault acquisition module configured to acquire a set of historical interval fault events that cause a fault disturbance of an integrated substation system; A secondary fault interval determination module configured to determine, based on a brainstorming optimization algorithm, a historical interval fault event that has the greatest impact on the integrated substation system from the set of historical interval fault events; An operation data acquisition module configured to acquire system operation data corresponding to a historical interval fault event that has the greatest impact on the integrated substation system when a known fault interval or a reconstruction interval occurs in parallel during a power outage; And a substation risk assessment module configured to calculate, based on the system operation data, outage risks and equipment risks of the remaining operation intervals in each substation, and then determine overall operation risk values of each substation in the system management range based on the outage risks and equipment risks of the remaining operation intervals in each substation; The outage risks of the remaining operation intervals in each substation include: a first outage risk corresponding to an outage of an operation interval caused by a known fault interval or a reconstruction interval in a substation during a power outage, and a second outage risk corresponding to an outage of an upper-level circuit breaker interval caused by a failure of a circuit breaker of an operation interval to be de-energized under a fault; The calculation formula of the first power failure risk is represented as: ； wherein represents the operation interval caused by the known fault interval or the modification interval in the substation during the outage the first outage risk corresponding to the outage, represents the operation interval the outgoing load factor of the operation interval, represents the electricity price per kilowatt-hour, represents the interval that has been out of service for maintenance the interval that is scheduled to be out of service and simulates a secondary fault the operation interval after the fault the probability of the fault outage, represents the operation interval the time point of the outage, represents the operation interval the outage recovery experience time, represents the operation interval in to the transmission power in the time period; The calculation formula of the second power failure risk is represented as: ； wherein a second outage risk corresponding to the fact that the breaker of the operating interval fails to interrupt under fault resulting in the outage of the upper level breaker interval, a failure rate of the breaker transformer as a function of the operating time, a time point of the outage of the interval , an outage recovery prediction time of the interval , a power predicted by the power curve for the operating interval for the upper level outage range outage time period, an operating time of the breaker of the operating interval . The device risk of each remaining operating interval in the substation is calculated by the following formula: ； wherein the equipment risk of the operating interval the equipment risk of the operating interval the equipment risk of the operating interval the overall primary equipment cost.

8. A computer readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the steps of the substation safety risk assessment method considering interval power failure according to any one of claims 1-6.

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