A distribution network power supply reliability assessment method, system and computer equipment

Abstract

The present invention relates to a method, system, computer equipment and readable storage medium for evaluating the reliability of power supply of a distribution network. According to the distribution of distribution automation switches, the distribution network is divided into large segments and small segments. Taking the fault segment as the origin, the line segment is divided into a large segment upstream of the fault, a large segment where the fault is located and a large segment downstream of the fault, and the large segment where the fault is located is divided into an upstream of the small segment where the fault is located, a downstream of the small segment where the fault is located and a small segment where the fault is located. The power outage time felt by users in different segments caused by different fault types occurring in different segments, the number of households during the power outage caused by the segment fault caused by each fault type, the number of households during the power outage caused by each fault type, the total number of households during the power outage of the distribution network, and the average power outage time per household are calculated in sequence, and the power supply reliability of the distribution network is evaluated according to the average power outage time per household. The demand for power supply reliability evaluation for urban distribution networks with a high level of distribution network automation coverage is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of distribution network evaluation, and in particular to a distribution network power supply reliability evaluation method, system, computer equipment and readable storage medium. Background Art

[0002] The reliability of power supply in the power system is an important indicator for judging the continuous power supply capacity of the power system. Among them, the reliability of power supply in the distribution network is directly related to the power quality of power users and is an important criterion for judging the power supply service capacity of power companies.

[0003] Prior art 1

[0004] The "Guidelines for Reliability Assessment of Medium and Low Voltage Distribution Networks" DL / T 1563 provides a method for calculating the reliability of distribution network power supply based on failure mode and consequence analysis. By analyzing all possible fault events and their consequences on the system, a failure mode and consequence analysis table is established, and the load point and system reliability indicators are calculated through the table. However, it is impossible to consider the impact of distribution automation on power supply reliability, and it is impossible to take into account the differences in power supply reliability caused by different distribution network automation configurations. With the increasing level of automation in urban distribution networks, it is necessary to take into account the impact of distribution automation and propose a distribution network power supply reliability method for urban distribution networks with a small base of fault outage time when conducting power supply reliability assessments.

[0005] Prior art 2

[0006] "A method for calculating the reliability of power supply of a distribution network considering multifunctional distribution automation" Application Publication Number: CN108564252 A provides a method for calculating the reliability of power supply of a distribution network considering multifunctional distribution automation, which comprehensively considers the different automation function configurations of the current distribution network and is divided into four functional modes: Class A (non-automatic mode), Class B (automatic positioning mode), Class C (automatic isolation mode) and Class D (automatic transfer mode). The power supply reliability of the line under different automation function modes is quantitatively analyzed, and the reliability index considering fault power outage is given.

[0007] The second prior art has the following problems:

[0008] 1) The isolation zone division method of the second prior art does not define the isolation area enclosed by different types of switches. In actual lines, it is relatively rare for the same type of switches to enclose an isolation zone. Usually, automated switches and non-automated switches are staggered. Therefore, the isolation zone is mostly enclosed by different types of switches. The second prior art cannot cope with the above actual scenarios.

[0009] 2) If the line is equipped with a Class A switch and the fault is located in the Class A isolation zone, the fault power outage time of the load point downstream of the Class A isolation zone is the transfer time in the automatic transfer mode. In actual distribution lines, even the load downstream of the automatic isolation zone may be limited by the transfer capacity and other reasons, and there may be a situation where the connection cannot be made but the power cannot be transferred. The second prior art cannot distinguish and consider this type of user, and the evaluation results are highly biased. Summary of the invention

[0010] The present invention provides a distribution network power supply reliability assessment method, system and computer-readable storage medium to solve the problem that the failure mode and effect analysis method does not take into account the impact of distribution automation, and the definition of automation isolation areas in other technical solutions is inconsistent with the actual distribution network feeder. The accuracy of the distribution network power supply reliability analysis results is improved to meet the needs of rapid and accurate assessment of urban distribution network power supply reliability.

[0011] In a first aspect, an embodiment of the present invention provides a method for evaluating the reliability of power supply in a distribution network, the method comprising:

[0012] The line segment of the distribution network is divided into sections, the line segment divided by the automatic switch is divided into several large sections, and within each large section, the line segment divided by the non-automatic switch is divided into small sections; and the line segment of the distribution network is divided into a large section upstream of the fault, a large section where the fault is located, and a large section downstream of the fault, and the large section where the fault is located is divided into a small section upstream of the fault, a small section downstream of the fault, and a small section where the fault is located;

[0013] According to the probability of occurrence of different fault types and the power outage time felt by users in different segments caused by the fault types in different segments, the number of households during the power outage caused by the segment fault caused by each fault type is calculated; according to the number of households during the power outage caused by the segment fault caused by each fault type and the collection of faults occurring in all segments of the distribution network, the number of households during the power outage caused by each fault type is calculated; the fault types include: cable system fault, overhead line system fault, large branch fault, and distribution transformer fault;

[0014] Sum the number of households during power outages caused by each fault type to obtain the total number of households during power outages in the distribution network;

[0015] Divide the total number of households during power outages in the distribution network by the total number of users in the distribution network to obtain an average power outage time per household;

[0016] The power supply reliability of the distribution network is evaluated according to the average power outage time per household to obtain an evaluation result.

[0017] In a further embodiment, the method for calculating the power outage time felt by the user includes:

[0018] The distribution network is divided into the following stages from the occurrence of a fault to the restoration of power to the entire line: fault occurrence, fault location, fault isolation, switching operation, fault repair, and restoration of power to the entire line;

[0019] According to different operation modes, the fault location, fault isolation and switching operations are divided into: manual location, isolation and switching operations and automatic location, isolation and switching operations;

[0020] The time required for manual positioning, isolation and switching operations is the time required for manual positioning, isolation and switching operations; the time required for automatic positioning, isolation and switching operations is the time required for automatic positioning, isolation and switching operations;

[0021] The time required from the fault repair to the full line power restoration is the fault repair power restoration time;

[0022] The power outage time felt by the user is determined based on the user's segment location, user type, and the manual positioning, isolation and switching operation time, the automated positioning, isolation and switching operation time, and the fault repair and power restoration time; the user types include: transferable users and non-transferable users.

[0023] In a further embodiment, the cable system fault and the overhead line system fault both include a line body fault and a section switch fault;

[0024] Calculate the number of households that experience power outages due to line failures, specifically:

[0025] According to the probability of occurrence of the line body fault and the power outage time felt by users in different sections caused by the line body fault in different sections, the number of households during the power outage caused by the section fault caused by the line body fault is calculated; according to the number of households during the power outage caused by the section fault caused by the line body fault and the collection of all sections of the line body fault, the number of households during the power outage caused by the line body fault is calculated;

[0026] The number of households during the power outage caused by the fault of the cable line is the number of households during the first power outage, and the number of households during the power outage caused by the fault of the overhead line is the number of households during the second power outage;

[0027] Calculate the number of households that will experience power outages due to sectionalizer failures, specifically:

[0028] According to the probability of occurrence of the sectional switch failure and the power outage time felt by users in different sections caused by the sectional switch failure, the number of households during the sectional switch failure power outage is calculated; according to the number of households during the sectional switch failure power outage and the collection of all sectional switch failures, the number of households during the power outage caused by the sectional switch failure is calculated;

[0029] The number of households during the power outage caused by the failure of the cable system section switch is the number of households during the third power outage, and the number of households during the power outage caused by the failure of the overhead line system section switch is the number of households during the fourth power outage.

[0030] In a further embodiment, the method for calculating the number of households when a power outage is caused by a large branch fault includes:

[0031] According to the line type of the large branch, the large branch is delineated into a cable system type large branch and an overhead line system type large branch;

[0032] If the large branch is a cable system type large branch, the number of households during the power outage caused by the cable system type large branch fault is calculated according to the method for calculating the number of households during the power outage caused by the line body fault and the section switch fault in the cable system fault;

[0033] If the large branch is an overhead line system type large branch, the number of households during the power outage caused by the overhead line system type large branch fault is calculated according to the method for calculating the number of households during the power outage caused by the line body fault and the section switch fault in the overhead line system fault;

[0034] The number of households during the power outage caused by the large branch failure is the number of households during the fifth power outage.

[0035] In a further embodiment, the method for calculating the number of households when a power outage is caused by a distribution transformer failure includes:

[0036] According to the occurrence probability of the distribution transformer failure and the power outage time felt by users in front of the distribution transformer caused by the distribution transformer failure, the number of households during the power outage caused by the distribution transformer failure is calculated, and the number of households during the power outage caused by the distribution transformer failure is the sixth power outage number.

[0037] In a further embodiment, the number of households during the first power outage, the number of households during the second power outage, the number of households during the third power outage, the number of households during the fourth power outage, the number of households during the fifth power outage, and the number of households during the sixth power outage are summed to obtain the total number of households during power outages in the distribution network.

[0038] In a second aspect, an embodiment of the present invention provides a distribution network power supply reliability assessment system, the system comprising:

[0039] Segmentation module: used to segment the line segments of the distribution network, divide the line segments divided by the automatic switch into several large segments, and divide the line segments divided by the non-automatic switch into small segments in each large segment; and divide the line segments of the distribution network twice with the fault segment as the origin, dividing the line segments into a large segment upstream of the fault, a large segment where the fault is located, and a large segment downstream of the fault, and dividing the large segment where the fault is located into a small segment upstream of the fault, a small segment downstream of the fault, and a small segment where the fault is located;

[0040] The module for calculating the number of households during power outages caused by each fault type is used to calculate the number of households during power outages caused by segment faults of each fault type according to the probability of occurrence of different fault types and the power outage time felt by users in different segments caused by the different fault types in different segments, and calculate the number of households during power outages caused by each fault type according to the number of households during power outages caused by segment faults of each fault type and the collection of faults in all segments of the distribution network; the fault types include: cable system faults, overhead line system faults, large branch faults, and distribution transformer faults;

[0041] A total power outage household number calculation module is used to sum the number of households during power outages caused by each fault type to obtain the total number of households during power outages in the distribution network;

[0042] The module for calculating the average power outage time per household is used to divide the total number of households in the distribution network during power outages by the total number of users in the distribution network to obtain the average power outage time per household;

[0043] Evaluation module: used to evaluate the power supply reliability of the distribution network according to the average power outage time per household to obtain an evaluation result.

[0044] In a third aspect, an embodiment of the present invention provides a computer device, including a memory, a processor and a transceiver, which are connected via a bus; the memory is used to store a set of computer program instructions and data, and can transmit the stored data to the processor, and the processor can execute the program instructions stored in the memory to perform the steps of the above method.

[0045] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium, in which a computer program is stored. When the computer program is executed, the steps of the above method are implemented.

[0046] The present invention provides a method, system, computer equipment and storage medium for evaluating the reliability of power supply of a distribution network. According to the distribution of distribution automation switches, the distribution network is divided into large sections and small sections. Taking the fault section as the origin, the line section is divided into a large section upstream of the fault, a large section where the fault is located and a large section downstream of the fault, and the large section where the fault is located is divided into an upstream of the small section where the fault is located, a downstream of the small section where the fault is located and a small section where the fault is located. The power outage time felt by users in different sections caused by different fault types occurring in different sections, the number of households during the power outage caused by the segment fault caused by each fault type, the number of households during the power outage caused by each fault type, the number of households during the overall power outage of the distribution network, and the average power outage time per household are calculated in sequence, and the power supply reliability of the distribution network is evaluated according to the average power outage time per household. The demand for power supply reliability evaluation of urban distribution networks with a high level of distribution network automation coverage is met. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1It is a schematic diagram of the steps of a method for evaluating the reliability of power supply of a distribution network according to an embodiment of the present invention;

[0048] Figure 2 It is a schematic diagram of the steps of a method for calculating the power outage time felt by users in a method for evaluating the reliability of power supply of a distribution network in an embodiment of the present invention;

[0049] Figure 3 Schematic diagram of the steps for calculating the number of households during a power outage due to a large branch fault in an embodiment of the present invention;

[0050] Figure 4 Schematic diagram of a power supply reliability assessment system for a distribution network according to an embodiment of the present invention;

[0051] Figure 5 It is a schematic diagram of a computer device in an embodiment of the present invention. DETAILED DESCRIPTION

[0052] The following is a detailed description of the implementation of the present invention in conjunction with the accompanying drawings. The embodiments are provided only for illustrative purposes and cannot be understood as limiting the present invention. The accompanying drawings are only for reference and illustration purposes and do not constitute a limitation on the scope of patent protection of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] like Figure 1 As shown, in an embodiment of the present invention, a method for evaluating the reliability of power supply in a distribution network is provided, and the method includes:

[0054] S1. Divide the line segments of the distribution network into segments, divide the line segments divided by the automatic switches into several large segments, and divide the line segments divided by the non-automatic switches into small segments in each large segment; and divide the line segments of the distribution network into a large upstream segment of the fault, a large segment where the fault is located, and a large downstream segment of the fault, and divide the large segment where the fault is located into a small segment upstream of the fault, a small segment downstream of the fault, and a small segment where the fault is located.

[0055] There are a large number of switches distributed in the distribution network lines, which are used to control the distribution and transmission of the distribution network lines. The switch types include automatic switches and non-automatic switches. The automatic switches include substation outlet switches, automatic disconnect switches, automatic contact switches, etc. In the distribution network lines, the line sections divided by the automatic switches are divided into several large sections, and the areas within the large sections are automatic isolation areas. In each large section, the line sections divided by the non-automatic switches are divided into small sections, and the areas inside the small sections are manual isolation areas.

[0056] After the distribution network is segmented according to the distribution of automatic switches, if a fault occurs in the distribution network, the small segment where the fault is located is the fault segment. Taking the fault segment as the origin, the line segment of the distribution network is divided into a large segment upstream of the fault, a large segment where the fault is located, and a large segment downstream of the fault. Among them, the large segment upstream of the fault segment is the large segment upstream of the fault, the large segment downstream of the fault segment is the large segment downstream of the fault, and the large segment where the fault segment is located is the large segment where the fault is located. And the large segment where the fault is located is divided into the small segment upstream of the fault, the small segment downstream of the fault, and the small segment where the fault is located.

[0057] S2. Calculate the number of households at the time of power outage caused by segment faults of each fault type based on the probability of occurrence of different fault types and the power outage time felt by users in different segments caused by the fault types occurring in different segments. Calculate the number of households at the time of power outage caused by segment faults of each fault type based on the number of households at the time of power outage caused by segment faults of each fault type and the collection of faults occurring in all segments of the distribution network. The fault types include: cable system fault, overhead line system fault, large branch fault, and distribution transformer fault.

[0058] In the distribution network, fault types are divided into cable system faults, overhead line system faults, large branch faults, and distribution transformer faults. Different fault types cause different numbers of households to experience power outages. Different fault segments cause different power outage times for users in different segments, such as Figure 2 As shown, the power outage time felt by the user is calculated according to the following method:

[0059] S10, dividing the distribution network from fault occurrence to full-line repair into: fault occurrence, fault location, fault isolation, switching operation, fault repair, and full-line power restoration.

[0060] S20. According to different operation modes, the fault location, fault isolation and switching operation are divided into: manual location, isolation and switching operation and automatic location, isolation and switching operation.

[0061] S30. The time required for the manual positioning, isolation and switching operations is the manual positioning, isolation and switching operation time; the time required for the automatic positioning, isolation and switching operations is the automatic positioning, isolation and switching operation time.

[0062] S40. The time required from the fault repair to the full line power restoration is the fault repair and power restoration time.

[0063] S50. Determine the power outage time felt by the user based on the user's segment location, user type, and the manual positioning, isolation and switching operation time, automated positioning, isolation and switching operation time, and fault repair and power restoration time; the user types include: dedicated users and non-transferable users.

[0064] During the emergency repair of the distribution network, the whole process from the occurrence of the fault to the restoration of power to the whole line can be divided into several key nodes: fault occurrence, fault location, fault isolation, switching operation, fault repair, and restoration of power to the whole line. Among them, the nodes of fault location, fault isolation, and switching operation are greatly affected by the automation of the distribution network. Therefore, the nodes of fault location, fault isolation, and switching operation are combined. According to the operation mode adopted, the fault location, fault isolation, and switching operation are divided into manual location, isolation and switching operation and automatic location, isolation and switching operation. The time required for manual location, isolation, and switching operation is the manual location, isolation, and switching operation time t dfm The time required for automatic positioning, isolation and switching operations is the automatic positioning, isolation and switching operation time t dfa The time required to repair the fault and restore power to the entire line is the fault repair and power restoration time t f .

[0065] After the fault type is determined, the power outage time felt by the user is determined based on the user's segment location, user type, and the differences in manual positioning, isolation and switching operation time, automated positioning, isolation and switching operation time, and fault repair and power restoration time.

[0066] Among them, user types include transferable users and non-transferable users. Users who can transfer power through contact points during a fault are defined as transferable users, and users who cannot transfer power through contact points are defined as non-transferable users.

[0067] This can fully consider the impact of automation during the distribution network emergency repair process, and can fully consider the situation where the downstream load of the automatic isolation area is restricted by the power transfer situation.

[0068] According to the above method, the power outage time felt by users in different sections caused by cable system faults in different sections is calculated. Cable system faults can be divided into cable line faults and cable line section switch faults. The corresponding table of power outage time felt by users in different sections caused by cable line faults in different sections is shown in Table 1:

[0069]

[0070]

[0071] The corresponding table of power outage time felt by users in different sections caused by cable system section switch failure in different sections is shown in Table 2:

[0072]

[0073] Calculate the power outage time felt by users in different sections caused by overhead line system faults in different sections. Overhead line system faults can be divided into overhead line faults and overhead line section switch faults. The corresponding table of power outage time felt by users in different sections caused by overhead line faults in different sections is shown in Table 3:

[0074]

[0075] The corresponding table of power outage time felt by users in different sections caused by overhead line system section switch failure in different sections is shown in Table 4:

[0076]

[0077]

[0078] Cable system faults and overhead line system faults both include line faults and section switch faults. The number of households affected by power outages due to line faults can be calculated using the following method:

[0079] According to the probability of occurrence of line faults and the power outage time felt by users in different sections caused by line faults in different sections, the number of households during the power outage caused by section faults due to line faults is calculated. According to the number of households during the power outage caused by section faults due to line faults and the sum of the number of faults in all sections of the line body, the number of households during the power outage caused by line faults is calculated.

[0080] Among them, the number of households during the power outage caused by the failure of the cable line body is the number of households during the first power outage. Specifically, the number of households during the section fault power outage caused by the failure of the cable line body TS(f1) is calculated using the formula:

[0081] TS(f1)=P(f1)∑t i N i ,

[0082] Among them, f1 represents the fault of the cable line itself, F CC represents the set of all cable line faults, f1∈F CC , P(f1) is the average annual probability of occurrence of f1, S i Indicates the cable line segment, i = 1, 2, ..., n, N i Indicates segment S i The corresponding number of users, t i For S i The relative position of the fault segment is S according to Table 1. i The power outage time felt by users in the area.

[0083] Then the number of households that experience power outages due to cable line failure is

[0084] Among them, the number of households during the power outage caused by the fault of the overhead line body is the number of households during the second power outage. Specifically, the number of households during the section fault power outage caused by the fault of the overhead line body TS(f2) is calculated using the formula:

[0085] TS(f2)=P(f2)∑t i N i ,

[0086] Among them, f2 represents the fault of the overhead line itself, F AA represents the set of all overhead line faults, f2∈F AA , P(f2) is the average annual probability of occurrence of f2, S i Indicates segmentation, i = 1, 2, ..., n, N i Indicates segment S i The corresponding number of users, t i For S i The relative position of the fault segment is S according to Table 3. i The power outage time felt by users in the area.

[0087] The number of households that will experience power outages due to overhead line faults is

[0088] The number of households affected by power outages due to section switch failures can be calculated using the following method:

[0089] According to the occurrence probability of the section switch failure and the power outage time felt by users in different sections caused by the section switch failure, the number of households during the section failure power outage caused by the section switch failure is calculated. According to the number of households during the section failure power outage caused by the section switch failure and the collection of all section switch failures, the number of households during the power outage caused by the section switch failure is calculated.

[0090] Among them, the number of households during the power outage caused by the failure of the cable system section switch is the number of households during the third power outage. Specifically, the number of households during the section fault power outage caused by the cable system section switch failure TS(f3) is calculated using the formula:

[0091] TS(f3)=P(f3)∑t i N i ,

[0092] Among them, f3 represents the cable system section switch failure, F CS represents the set of all cable system section switch faults, f3∈F CS , P(f3) is the annual average probability of occurrence of f3, S i Indicates segmentation, i = 1, 2, ..., n, N i Indicates segment S i The corresponding number of users, ti For S i The relative position of the fault segment is S according to Table 2. i The power outage time felt by users in the area.

[0093] Then the number of households that will experience power outages due to cable system section switch failure is

[0094] Among them, the number of households during the power outage caused by the overhead line system section switch failure is the number of households during the fourth power outage. Specifically, the number of households during the section fault power outage caused by the overhead line system section switch failure TS(f4) is calculated using the formula:

[0095] TS(f4)=P(f4)∑t i N i ,

[0096] Among them, f4 represents the overhead line system section switch failure, F AC represents the set of all overhead line system section switch faults, f4∈F AC , P(f4) is the average annual probability of occurrence of f4, S i Indicates segmentation, i = 1, 2, ..., n, N i Indicates segment S i The corresponding number of users, t i For S i The relative position of the fault segment is S according to Table 4. i The power outage time felt by users in the area.

[0097] Then the number of households that will experience power outages due to overhead line system section switch failure is

[0098] The above method can be used to obtain the number of households experiencing power outages caused by cable system failures and overhead line system failures.

[0099] The impact of a large branch fault will not be transmitted to the main line, and the large branch can be regarded as an independent line, such as Figure 3 As shown in the figure, the method for calculating the number of households when a power outage is caused by a large branch fault is as follows:

[0100] S100. According to the line type of the large branch, the large branch is demarcated into a cable system type large branch and an overhead line system type large branch.

[0101] S200. If the large branch is a cable system type large branch, the number of households caused by the power outage due to the cable system type large branch fault is calculated according to the method for calculating the number of households caused by the power outage due to the line body fault and the section switch fault in the cable system fault.

[0102] S300. If the large branch is an overhead line system type large branch, the number of households caused by the power outage due to the overhead line system type large branch fault is calculated according to the method for calculating the number of households caused by the power outage due to the line body fault and the section switch fault in the overhead line system fault.

[0103] S400. The number of households during the power outage caused by the large branch failure is the number of households during the fifth power outage.

[0104] According to the line type of the large branch, the large branch line is classified into types. If the large branch is a cable system line, it is a cable system type large branch. If the large branch is an overhead line system line, it is an overhead line system type large branch. Select the corresponding calculation method according to the type of the large branch system. If the large branch is a cable system type large branch, the number of households during the power outage caused by the cable system type large branch fault is calculated according to the calculation method for calculating the number of households during the power outage caused by the line body fault and the section switch fault in the cable system fault; if the large branch is an overhead line system type large branch, the number of households during the power outage caused by the overhead line system type large branch fault is calculated according to the calculation method for calculating the number of households during the power outage caused by the line body fault and the section switch fault in the overhead line system fault. The number of households during the power outage caused by the large branch fault is the fifth number of households during the power outage, expressed as: Among them, f5 represents a large branch fault, F B represents the set of all large branch faults, f5∈F B .

[0105] The front end of the distribution transformer is equipped with protection equipment, such as fuses. Its failure and outage will affect the users it carries. According to the probability of distribution transformer failure and the power outage time felt by all users in front of the distribution transformer caused by the distribution transformer failure, the number of households during the power outage caused by the distribution transformer failure is calculated as P(f6)Nt t , where f6 represents the distribution transformer failure, P(f6) is the annual average probability of distribution transformer failure, N is the total number of distribution lines, and t t The power outage time felt by users in front of the distribution transformer due to the distribution transformer failure is the time required for the entire process from the distribution transformer failure to the full line power restoration. The number of households at the time of power outage caused by the distribution transformer failure is the number of households at the sixth power outage.

[0106] S3. Sum the number of households during power outages caused by each fault type to obtain the total number of households during power outages in the distribution network. In this embodiment, the number of households during the first power outage, the number of households during the second power outage, the number of households during the third power outage, the number of households during the fourth power outage, the number of households during the fifth power outage, and the number of households during the sixth power outage are summed to obtain the total number of households during power outages in the distribution network:

[0107]

[0108] S4. Divide the total number of households in the distribution network during power outages by the total number of users in the distribution network to obtain the average power outage time per household. SAIDI is used to represent the average power outage time per household, that is, the average number of power outage hours per user in a unit year, and the calculation formula is: Where N is the total number of households connected to the distribution line.

[0109] S5. Evaluate the power supply reliability of the distribution network according to the average power outage time per household to obtain an evaluation result.

[0110] The power supply reliability of the distribution network is evaluated based on the size of SAIDI. The larger the SAIDI, the longer the power outage time users may experience each year and the less reliable the system is. Conversely, the smaller the SAIDI, the more reliable the system is.

[0111] A distribution network power supply reliability assessment method provided by an embodiment of the present invention divides the distribution line into large segments and small segments according to the distribution of distribution automation switches by demarcating distribution automation zones. The line segment of the distribution network is divided twice with the fault segment as the origin, and the line segment is divided into a large segment upstream of the fault, a large segment where the fault is located, and a large segment downstream of the fault, and the large segment where the fault is located is divided into an upstream of the small segment where the fault is located, a downstream of the small segment where the fault is located, and a small segment where the fault is located. According to the probability of occurrence of different fault types and the power outage time felt by users in different segments caused by the occurrence of the fault type in different segments, the number of households during the power outage caused by the segment fault caused by each fault type is calculated, and the number of households during the power outage caused by each fault type is calculated according to the number of households during the power outage caused by the segment fault caused by each fault type and the collection of faults in all segments of the distribution network. The number of households during the power outage caused by each fault type is summed, and then divided by the total number of users in the distribution network to calculate the average power outage time per household, and the power supply reliability of the distribution network is evaluated according to the average power outage time per household. The present invention solves the problem that the existing technical solution 1 cannot take into account the impact of distribution network automation, and the existing technical solution 2 cannot take into account the staggered distribution of automated switches and non-automated switches and the possibility that the downstream load of the automatic isolation area may not be able to transfer power. This realizes the demand for power supply reliability assessment for urban distribution networks with a high level of distribution network automation coverage.

[0112] like Figure 4 As shown, based on a distribution network power supply reliability assessment method, an embodiment of the present invention further proposes a distribution network power supply reliability assessment system, the system comprising:

[0113] Segmentation module 1: used to segment the line segments of the distribution network, divide the line segments divided by the automatic switches into several large segments, and in each large segment, divide the line segments divided by the non-automatic switches into small segments; and take the fault segment as the origin to perform secondary division on the line segments of the distribution network, divide the line segments into a large upstream segment of the fault, a large segment where the fault is located, and a large downstream segment of the fault, and divide the large segment where the fault is located into a small segment upstream of the fault, a small segment downstream of the fault, and a small segment where the fault is located.

[0114] Module 2 for calculating the number of households during power outages due to different fault types: used to calculate the number of households during power outages caused by segment faults according to the probability of occurrence of different fault types and the power outage time felt by users in different segments caused by the different fault types occurring in different segments, and to calculate the number of households during power outages caused by each fault type according to the number of households during power outages caused by segment faults due to each fault type and the collection of faults occurring in all segments of the distribution network; the fault types include: cable system fault, overhead line system fault, large branch fault, and distribution transformer fault.

[0115] The total number of households during power outage calculation module 3 is used to sum the number of households during power outage caused by each fault type to obtain the total number of households during power outage of the distribution network.

[0116] The module 4 for calculating the average power outage time per household is used to divide the total number of households experiencing power outages in the distribution network by the total number of users in the distribution network to obtain the average power outage time per household.

[0117] Evaluation module 5: used to evaluate the power supply reliability of the distribution network according to the average power outage time per household to obtain an evaluation result.

[0118] For the specific definition of a distribution network power supply reliability assessment system, please refer to the above-mentioned definition of a distribution network power supply reliability assessment method, which will not be repeated here. A person of ordinary skill in the art will appreciate that the various modules and steps described in conjunction with the embodiments disclosed in this application can be implemented in hardware, software, or a combination of both. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0119] like Figure 5 As shown, a computer device provided by an embodiment of the present invention includes a memory, a processor and a transceiver, which are connected via a bus; the memory is used to store a set of computer program instructions and data, and can transmit the stored data to the processor, and the processor can execute the program instructions stored in the memory to execute the steps of the above-mentioned distribution network power supply reliability assessment method.

[0120] The memory may include a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories; the processor may be a central processing unit, a microprocessor, an application-specific integrated circuit, a programmable logic device, or a combination thereof. By way of example but not limitation, the programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic, or any combination thereof.

[0121] Additionally, the memory may be a physically separate unit or may be integrated with the processor.

[0122] It can be understood by those skilled in the art that Figure 5 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have the same component arrangement.

[0123] In one embodiment, a computer-readable storage medium is provided, wherein the storage medium is used to store one or more computer programs, wherein the one or more computer programs include program codes, and when the computer programs are run on a computer, the program codes are used to execute the above-mentioned distribution network power supply reliability assessment method.

[0124] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented by software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present invention is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., an SSD), etc.

[0125] Similarly, the contents of the above method embodiments are all applicable to the present storage medium embodiments. The functions specifically implemented by the present storage medium embodiments are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0126] In this embodiment, a distribution network power supply reliability assessment method, system, computer equipment and computer storage medium are provided. The existing failure mode consequence analysis method does not take into account the impact of distribution automation, and other technical solutions have the problem that the definition of the automation isolation zone is inconsistent with the actual distribution network feeder. According to the distribution of distribution automation switches, the distribution network is divided into large segments and small segments. And taking the fault segment as the origin, the line segment of the distribution network is divided into a large upstream segment of the fault, a large segment where the fault is located and a large downstream segment of the fault, and the large segment where the fault is located is divided into the upstream of the small segment where the fault is located, the downstream of the small segment where the fault is located and the small segment where the fault is located. For different fault types, the power outage time felt by users in different segments caused by the occurrence of the fault type in different segments, the number of households during the power outage caused by each fault type, and the number of households during the power outage caused by each fault type are calculated in turn, the number of households during the power outage caused by each fault type is summed, and then divided by the total number of users in the distribution network, the average power outage time per household is calculated, and the power supply reliability of the distribution network is evaluated according to the average power outage time per household. Improve the accuracy of distribution network power supply reliability analysis results and meet the needs of conducting power supply reliability assessments for urban distribution networks with a high level of distribution network automation coverage.

[0127] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing related hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods.

[0128] The above-mentioned embodiments only express several preferred implementation modes of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in the technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be regarded as the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be based on the protection scope of the claims.

Claims

1. A method for evaluating the reliability of power supply in a distribution network, characterized in that: The method comprises: The line section of the distribution network is divided into sections, the line section between two adjacent automatic switches is divided into large sections, and within each large section, the line section separated by the non-automatic switch is divided into small sections; and the line section of the distribution network is divided into a large section upstream of the fault, a large section where the fault is located, and a large section downstream of the fault, with the fault point as the origin, and the large section where the fault is located is divided into a small section upstream of the fault, a small section downstream of the fault, and a small section where the fault is located; According to the probability of occurrence of different fault types and the power outage time felt by users in different segments caused by the fault types in different segments, the number of households during the power outage caused by the segment fault caused by each fault type is calculated; according to the number of households during the power outage caused by the segment fault caused by each fault type and the collection of faults occurring in all segments of the distribution network, the number of households during the power outage caused by each fault type is calculated; the fault types include: cable system fault, overhead line system fault, large branch fault and distribution transformer fault; Sum the number of households during power outages caused by each fault type to obtain the total number of households during power outages in the distribution network; Divide the total number of households during power outages in the distribution network by the total number of users in the distribution network to obtain an average power outage time per household; Evaluate the power supply reliability of the distribution network according to the average power outage time per household to obtain an evaluation result; The cable system fault and overhead line system fault both include line body fault and section switch fault; Calculate the number of households that experience power outages due to line faults, specifically: According to the probability of occurrence of the line body fault and the power outage time felt by users in different sections caused by the line body fault in different sections, the number of households during the power outage caused by the section fault caused by the line body fault is calculated; according to the number of households during the power outage caused by the section fault caused by the line body fault and the collection of all sections of the line body fault, the number of households during the power outage caused by the line body fault is calculated; The number of households during the power outage caused by the fault of the cable line is the number of households during the first power outage, and the number of households during the power outage caused by the fault of the overhead line is the number of households during the second power outage; Calculate the number of households that experience power outages due to sectionalizer failures, specifically: According to the probability of occurrence of the sectional switch failure and the power outage time felt by users in different sections caused by the sectional switch failure, the number of households during the sectional switch failure power outage is calculated; according to the number of households during the sectional switch failure power outage and the collection of all sectional switch failures, the number of households during the power outage caused by the sectional switch failure is calculated; The number of households during the power outage caused by the failure of the cable system section switch is the number of households during the third power outage, and the number of households during the power outage caused by the failure of the overhead line system section switch is the number of households during the fourth power outage; The method for calculating the number of households when a power outage is caused by a large branch fault includes: According to the line type of the large branch, the large branch is delineated into a cable system type large branch and an overhead line system type large branch; If the large branch is a cable system type large branch, the number of households during the power outage caused by the cable system type large branch fault is calculated according to the method for calculating the number of households during the power outage caused by the line body fault and the section switch fault in the cable system fault; If the large branch is an overhead line system type large branch, the number of households during the power outage caused by the overhead line system type large branch fault is calculated according to the method for calculating the number of households during the power outage caused by the line body fault and the section switch fault in the overhead line system fault; The number of households during the power outage caused by the large branch failure is the number of households during the fifth power outage; The method for calculating the number of households when a power outage is caused by a distribution transformer failure includes: According to the occurrence probability of the distribution transformer failure and the power outage time felt by users in front of the distribution transformer caused by the distribution transformer failure, the number of households during the power outage caused by the distribution transformer failure is calculated, and the number of households during the power outage caused by the distribution transformer failure is the sixth power outage number.

2. A method for evaluating the reliability of power supply in a distribution network according to claim 1, characterized in that: The method for calculating the power outage time felt by users comprises: The distribution network is divided into the following stages from the occurrence of a fault to the restoration of power to the entire line: fault occurrence, fault location, fault isolation, switching operation, fault repair, and restoration of power to the entire line; According to different operation modes, the fault location, fault isolation and switching operations are divided into: manual location, isolation and switching operations and automatic location, isolation and switching operations; The time required for manual positioning, isolation and switching operations is the time required for manual positioning, isolation and switching operations; the time required for automatic positioning, isolation and switching operations is the time required for automatic positioning, isolation and switching operations; The time required from the fault repair to the full line power restoration is the fault repair power restoration time; The power outage time felt by the user is determined based on the user's segment location, user type, and the manual positioning, isolation and switching operation time, the automated positioning, isolation and switching operation time, and the fault repair and power restoration time; the user types include: transferable users and non-transferable users.

3. A method for evaluating the reliability of power supply in a distribution network according to claim 1, characterized in that: The total number of households during power outages in the distribution network is obtained by summing the number of households during the first power outage, the second power outage, the third power outage, the fourth power outage, the fifth power outage and the sixth power outage to obtain the total number of households during power outages in the distribution network.

4. A distribution network power supply reliability assessment system, characterized in that: The system comprises: Segmentation module: used to segment the line segment of the distribution network, divide the line segment between two adjacent automatic switches into large segments, and in each large segment, divide the line segment separated by the non-automatic switch into small segments; and divide the line segment of the distribution network into a large upstream segment of the fault, a large segment where the fault is located, and a large downstream segment of the fault with the fault point as the origin, and divide the large segment where the fault is located into a small segment upstream of the fault, a small segment downstream of the fault, and a small segment where the fault is located; The module for calculating the number of households during power outages caused by each fault type is used to calculate the number of households during power outages caused by segment faults of each fault type according to the probability of occurrence of different fault types and the power outage time felt by users in different segments caused by the different fault types in different segments, and calculate the number of households during power outages caused by each fault type according to the number of households during power outages caused by segment faults of each fault type and the collection of faults in all segments of the distribution network; the fault types include: cable system faults, overhead line system faults, large branch faults, and distribution transformer faults; Total power outage duration calculation module: used to sum the power outage duration caused by each fault type to obtain the total power outage duration of the distribution network; Average power outage time calculation module for each household: used to divide the total power outage time of the distribution network by the total number of users of the distribution network to obtain the average power outage time for each household; Evaluation module: used to evaluate the power supply reliability of the distribution network according to the average power outage time per household, and obtain an evaluation result; The cable system fault and overhead line system fault both include line body fault and section switch fault; Calculate the number of households that experience power outages due to line faults, specifically: According to the probability of occurrence of the line body fault and the power outage time felt by users in different sections caused by the line body fault in different sections, the number of households during the power outage caused by the section fault caused by the line body fault is calculated; according to the number of households during the power outage caused by the section fault caused by the line body fault and the collection of all sections of the line body fault, the number of households during the power outage caused by the line body fault is calculated; The number of households during the power outage caused by the fault of the cable line is the number of households during the first power outage, and the number of households during the power outage caused by the fault of the overhead line is the number of households during the second power outage; Calculate the number of households that experience power outages due to sectionalizer failures, specifically: According to the probability of occurrence of the sectional switch failure and the power outage time felt by users in different sections caused by the sectional switch failure, the number of households during the sectional switch failure power outage is calculated; according to the number of households during the sectional switch failure power outage and the collection of all sectional switch failures, the number of households during the power outage caused by the sectional switch failure is calculated; The number of households during the power outage caused by the failure of the cable system section switch is the number of households during the third power outage, and the number of households during the power outage caused by the failure of the overhead line system section switch is the number of households during the fourth power outage; The method for calculating the number of households when a power outage is caused by a large branch fault includes: According to the line type of the large branch, the large branch is delineated into a cable system type large branch and an overhead line system type large branch; If the large branch is a cable system type large branch, the number of households during the power outage caused by the cable system type large branch fault is calculated according to the method for calculating the number of households during the power outage caused by the line body fault and the section switch fault in the cable system fault; If the large branch is an overhead line system type large branch, the number of households during the power outage caused by the overhead line system type large branch fault is calculated according to the method for calculating the number of households during the power outage caused by the line body fault and the section switch fault in the overhead line system fault; The number of households during the power outage caused by the large branch failure is the number of households during the fifth power outage; The method for calculating the number of households when a power outage is caused by a distribution transformer failure includes: According to the occurrence probability of the distribution transformer failure and the power outage time felt by users in front of the distribution transformer caused by the distribution transformer failure, the number of households during the power outage caused by the distribution transformer failure is calculated, and the number of households during the power outage caused by the distribution transformer failure is the sixth power outage number.

5. A computer device, characterized in that: It includes a memory, a processor and a transceiver, which are connected via a bus; the memory is used to store a set of computer program instructions and data, and transmit the stored data to the processor, and the processor executes the program instructions stored in the memory to execute the distribution network power supply reliability assessment method as described in any one of claims 1 to 3.

6. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed, the method for evaluating the reliability of power supply in a distribution network as claimed in any one of claims 1 to 3 is implemented.

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