Method and device for evaluating reliability of power distribution network in same-station and same-bus connection mode
By acquiring and analyzing the multi-faceted reliability of the same station and same mother power supply structure, using fault tree and Bayesian network model, the problem of insufficient reliability assessment of the distribution network of the same station and same mother connection method in the existing technology is solved, and the realization of the implementation of the problem of insufficient reliability assessment of the distribution network. More accurate and comprehensive reliability assessments.
Patent Information
- Application Number
- CN202411386488.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-30
- Publication Date
- 2025-01-10
AI Technical Summary
The existing technology lacks an effective distribution network reliability evaluation method for the same station and mother connection method, and cannot fully reflect the reliability of the same station and mother transfer power supply structure.
By obtaining the first reliability of the common parts of the same station and mother transfer power supply structure, the second reliability of the target load point in the main power supply line and the third reliability of the power supply line, fault tree analysis and Bayesian The network model, combined with weighting processing, determines the reliability of the power supply structure of the same station and the same mother.
A multi-faceted reliability assessment of the power supply structure of the same station and the same mother has been achieved, which improves the accuracy and comprehensiveness of the assessment, can find potential problems and weak links, and provides a basis for optimization work.
Smart Images
Figure CN119298005A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of distribution network, and in particular to a method and device for evaluating the reliability of a distribution network in a same-station and same-mother connection mode. Background Art
[0002] The same-station same-bus connection mode refers to a distribution network connection mode in which multiple feeders or loads are connected to the same bus in the same substation.
[0003] At present, the following two methods are usually used to evaluate the reliability of distribution networks with the same station and mother connection mode: 1) Simulation method, by building a topology diagram corresponding to the system, inputting the reliability parameters of related devices and equipment, and then calculating the system reliability through simulation method; 2) Linear estimation based on the system structure.
[0004] However, there is still a lack of distribution network evaluation methods for the same-station and same-bus connection mode. Summary of the invention
[0005] Based on this, it is necessary to provide a distribution network reliability assessment method for the same-station and same-mother connection mode that can perform reliability assessment on distribution networks with the same-station and same-mother connection mode in order to address the above technical problems.
[0006] In a first aspect, the present application provides a method for evaluating the reliability of a distribution network in a same-station same-mother connection mode, comprising:
[0007] Obtaining the first reliability corresponding to the common part in the same-station and same-mother power supply structure, the second reliability corresponding to the target load point in the main power supply line in the same-station and same-mother power supply structure, and the third reliability of the target load point in the power supply transfer line;
[0008] The reliability of the same-station and same-mother power supply structure is determined based on the first reliability, the second reliability and the third reliability.
[0009] In one of the embodiments, the common parts include at least one of a transformer, a substation, a busbar system, a disconnector, a circuit breaker, a current transformer, a voltage transformer, a lightning arrester and an overvoltage protection device.
[0010] In one embodiment, obtaining the second reliability corresponding to the target load point in the main power supply line in the same-station same-mother power supply structure includes:
[0011] In the same-station and same-mother power supply structure, a fault tree is constructed for the power supply path of the target load point in the main power supply line;
[0012] Based on the fault analysis tree, various fault modes that lead to power outages at load points are analyzed;
[0013] According to the occurrence probability of each failure mode, the second reliability corresponding to the target load point in the main power supply line in the same station and same mother power supply structure is determined.
[0014] In one embodiment, obtaining the third reliability of the target load point in the power transfer line includes:
[0015] Construct a Bayesian network model of the target load point in the power supply line in the same-station and same-mother power supply structure; the Bayesian network model should include each component in the power supply line and its failure probability and the impact of the failure on the power supply of the target load point;
[0016] The third reliability of the target load point in the power supply line based on the Bayesian network model.
[0017] In one embodiment, determining the reliability of the same-station same-mother power supply structure according to the first reliability, the second reliability, and the third reliability includes:
[0018] The first reliability, the second reliability and the third reliability are weighted according to their corresponding weight coefficients to obtain the reliability of the same-station and same-mother power supply structure.
[0019] In one of the embodiments, if the common part includes a transformer and a substation, the first reliability is determined according to the failure rate and failure repair time corresponding to the common part in the same-station and same-mother power supply structure.
[0020] In one of the embodiments, the second reliability corresponding to the target load point in the same-station same-mother power supply structure in the main power supply line is determined according to the failure rate and failure repair time of the target load point in the same-station same-mother power supply structure in the main power supply line;
[0021] The failure rate of the target load point in the main power supply line in the same-station same-mother power supply structure is determined according to the failure rate of the target load point in the main power supply line in the same-station same-mother power supply structure, the length of the line, the failure rate of the switch and the number of switches;
[0022] Among them, the fault repair time of the target load point in the main power supply line in the same-station same-mother power supply structure is determined according to the failure rate of the line in the main power supply line of the target load point in the same-station same-mother power supply structure, the fault repair time of the line, the length of the line, the failure rate of the switch, the fault repair time of the switch and the number of switches, as well as the failure rate of the target load point in the main power supply line in the same-station same-mother power supply structure.
[0023] In one of the embodiments, the third reliability of the target load point in the power transfer line is determined according to the failure rate and failure repair time of the target load point in the power transfer line;
[0024] The failure rate of the target load point in the transfer power supply line is determined according to the failure rate of the target load point in the transfer power supply line in the same station and same mother transfer power supply structure, the length of the line, the failure rate of the switch and the number of switches;
[0025] Among them, the fault repair time of the target load point in the transfer power supply line in the same-station and same-mother transfer power supply structure is determined according to the failure rate of the line in the transfer power supply line of the target load point in the same-station and same-mother transfer power supply structure, the fault repair time of the line, the length of the line, the failure rate of the switch, the fault repair time of the switch and the number of switches, as well as the failure rate of the target load point in the transfer power supply line in the same-station and same-mother transfer power supply structure.
[0026] In one embodiment, determining the reliability of the same-station same-mother power supply structure according to the first reliability, the second reliability, and the third reliability includes:
[0027] Determine the power transfer success rate of the target load point based on the fault repair time, the fault rate of the target load point in the power transfer line and the fault repair time;
[0028] Determine the failure rate and fault repair time of the target load point based on the transfer success rate of the target load point, the failure rate and fault repair time of the common parts, and the failure rate and fault repair time of the target load point in the main power supply line;
[0029] The reliability of the same-station and same-mother power supply structure is determined based on the failure rate and failure repair time of the target load point.
[0030] In a second aspect, the present application also provides a distribution network reliability assessment device in a same-station same-mother connection mode, comprising:
[0031] A branch acquisition module is used to obtain the first reliability corresponding to the common part in the same-station and same-mother power supply structure, the second reliability corresponding to the target load point in the main power supply line in the same-station and same-mother power supply structure, and the third reliability of the target load point in the power supply line;
[0032] The comprehensive evaluation module is used to determine the reliability of the same-station and same-mother power supply structure based on the first reliability, the second reliability and the third reliability.
[0033] The above-mentioned distribution network reliability assessment method of the same-station same-mother connection mode, this application not only considers the first reliability of the common part in the same-station same-mother power supply structure, but also evaluates the second reliability and third reliability of the target load point in the main power supply line and the power supply line respectively. This method of comprehensively considering multiple factors can more comprehensively reflect the reliability level of the same-station same-mother power supply structure. By evaluating the reliability of different parts and lines separately and considering them comprehensively, the impact of a single factor or line on the overall reliability assessment can be reduced, thereby improving the accuracy of the assessment. During the evaluation process, potential problems or weak links in the same-station same-mother power supply structure may be found. For example, the reliability of a certain line is low, the equipment failure rate is high, or the maintenance time is long. The discovery of these problems can provide an important basis for subsequent optimization work.
[0034] According to the failure rate and fault repair time of the common parts in the same-station and same-mother power supply structure, the failure rate and fault repair time of the target load point in the main power supply line in the same-station and same-mother power supply structure, and the failure rate and fault repair time of the target load point in the power supply transfer line, it is possible to implement fault assessment of each part in the same-station and same-mother power supply structure, and improve the accuracy of reliability analysis through the comprehensiveness of fault analysis. BRIEF DESCRIPTION OF THE DRAWINGS
[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the drawings required for use in the embodiments of the present application or related technical descriptions will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.
[0036] Figure 1 It is a flowchart of a method for evaluating the reliability of a distribution network in a same-station same-mother connection mode in one embodiment;
[0037] Figure 2 This is an application environment diagram of a distribution network reliability assessment method in a same-station same-mother connection mode in an embodiment. DETAILED DESCRIPTION
[0038] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.
[0039] In an exemplary embodiment, Figure 1As shown, a method for evaluating the reliability of a distribution network in a same-station same-mother connection mode is provided, and the method is applied to a computer device as an example for explanation, including the following S101 to S102. Among them:
[0040] S101, obtain the first reliability corresponding to the common part in the same-station and same-mother power supply transfer structure, the second reliability corresponding to the target load point in the main power supply line in the same-station and same-mother power supply transfer structure, and the third reliability of the target load point in the transfer power supply line.
[0041] Among them, the common parts are key components of the same-station and same-bus power supply structure, such as transformers, substations, busbar systems, etc. Obtaining the first reliability of these common parts usually involves collecting historical fault data, conducting equipment evaluations, or using reliability prediction models. The first reliability reflects the performance of the common parts under normal operating conditions and fault conditions, and is the basis for evaluating the reliability of the entire power supply structure.
[0042] The target load point refers to the load point that needs special attention in the same-station and same-mother power supply structure. The main power supply line is the main path to provide power to the target load point. To obtain the second reliability, it is necessary to analyze the failure mode, failure probability and the impact of the failure on the power supply of the target load point in the main power supply line.
[0043] Among them, the transfer power supply line is a backup path to provide power to the target load point when the main power supply line fails. Obtaining the third reliability also requires analyzing the failure mode, failure probability and the impact of the failure on the power supply of the target load point in the transfer power supply line. Since the transfer power supply line is usually used as a backup, its reliability requirements may be different from those of the main power supply line, but they are equally important.
[0044] S102, determining the reliability of the same-station same-mother power supply structure according to the first reliability, the second reliability and the third reliability.
[0045] Specifically, based on the first, second and third reliability data obtained, a comprehensive evaluation is conducted on the same-station and same-mother power supply structure. The evaluation process should take into account the mutual influence and dependency between the common parts, main power supply lines and power supply lines. Determine the reliability indicators of the power supply structure, such as power supply availability, mean time between failures (MTBF), fault recovery time, etc. These indicators should be able to fully reflect the reliability level of the power supply structure and be easy for decision makers and operation and maintenance personnel to understand and use.
[0046] The above-mentioned distribution network reliability assessment method of the same-station same-mother connection mode, this application not only considers the first reliability of the common part in the same-station same-mother power supply structure, but also evaluates the second reliability and third reliability of the target load point in the main power supply line and the power supply line respectively. This method of comprehensively considering multiple factors can more comprehensively reflect the reliability level of the same-station same-mother power supply structure. By evaluating the reliability of different parts and lines separately and considering them comprehensively, the impact of a single factor or line on the overall reliability assessment can be reduced, thereby improving the accuracy of the assessment. During the evaluation process, potential problems or weak links in the same-station same-mother power supply structure may be found. For example, the reliability of a certain line is low, the equipment failure rate is high, or the maintenance time is long. The discovery of these problems can provide an important basis for subsequent optimization work.
[0047] In one of the embodiments, the common parts include at least one of a transformer, a substation, a busbar system, a disconnector, a circuit breaker, a current transformer, a voltage transformer, a lightning arrester and an overvoltage protection device.
[0048] In one implementable method, the second reliability corresponding to the target load point in the same-station same-mother power supply structure in the main power supply line is obtained, including: in the same-station same-mother power supply structure, a fault tree is constructed for the power supply path of the target load point in the main power supply line; based on the fault analysis tree, various failure modes that cause power outages at the load point are analyzed; and according to the probability of occurrence of each failure mode, the second reliability corresponding to the target load point in the same-station same-mother power supply structure in the main power supply line is determined.
[0049] Specifically, determine the target load point in the same-station and same-mother power supply structure, and clarify its power supply path in the main power supply line. Along the power supply path, identify all elements that may cause faults, including but not limited to switches, transformers, line sections, protection devices, etc. Use the fault tree analysis method to combine these fault elements according to logical relationships (such as AND gates, OR gates) to form a fault tree representing the fault propagation path. Through the fault tree, identify all fault modes that may cause power outages at the target load point. Each fault mode represents a specific fault combination and propagation path.
[0050] For each failure mode, analyze its specific impact on the power supply of the target load point, including the duration and scope of the power outage. Collect historical data or conduct expert evaluation to determine the probability of each failure mode. This may require consideration of multiple factors such as the aging of the equipment, the operating environment, and the maintenance strategy. Based on the structure of the fault tree and the probability of each failure mode, use reliability assessment methods (such as probability theory, Markov process, etc.) to calculate the second reliability of the target load point in the main power supply line. This usually involves complex mathematical operations and model building.
[0051] In one implementable method, obtaining the third reliability of the target load point in the power transfer line includes: constructing a Bayesian network model of the target load point in the power transfer line in the same-station and same-mother power transfer structure; wherein the Bayesian network model should include each component in the power transfer line and its failure probability and the impact of the failure on the power supply to the target load point; based on the Bayesian network model, the third reliability of the target load point in the power transfer line.
[0052] First, it is necessary to identify the various components in the power supply line, including switches, transformers, line segments, protection devices, etc., and use them as nodes in the Bayesian network. Then, determine the logical relationship between these nodes, that is, the dependency and influence direction between them. This is usually based on the physical structure and operating principle of the system.
[0053] For each node, its failure probability needs to be set. This can be obtained through historical data, expert evaluation or experimental testing. The failure probability reflects the likelihood of component failure. Determine the impact of each component failure on the power supply of the target load point. This includes the power outage time, power outage scope, and possible recovery measures. These impacts will be represented as conditional probabilities in the Bayesian network.
[0054] The set failure probability and failure impact are input into the Bayesian network model. These data will be used as input parameters of the model to calculate the reliability of the target load point. Using the Bayesian network reasoning algorithm, the third reliability of the target load point in the power transfer line is calculated based on the input data and network structure. The reasoning process will consider the dependencies between the various components and the fault propagation path. The calculation results are output as easy-to-understand reliability indicators, such as power supply availability, mean time between failures (MTBF), etc. These indicators can intuitively reflect the reliability level of the target load point in the power transfer line.
[0055] In one of the embodiments, the reliability of the same-station same-mother power supply structure is determined based on the first reliability, the second reliability and the third reliability, including: weighting the first reliability, the second reliability and the third reliability according to the weighting coefficients corresponding to the first reliability, the second reliability and the third reliability respectively, to obtain the reliability of the same-station same-mother power supply structure.
[0056] In an exemplary embodiment, Figure 2 As shown, the common parts include transformers and substations; the first reliability is determined according to the failure rate and fault repair time corresponding to the common parts in the same-station and same-mother power supply structure.
[0057] In an implementable manner, the second reliability corresponding to the target load point in the same-station same-mother power supply structure in the main power supply line is determined according to the failure rate and failure repair time of the target load point in the same-station same-mother power supply structure in the main power supply line;
[0058] The failure rate of the target load point in the main power supply line in the same-station same-mother power supply structure is determined according to the failure rate of the target load point in the main power supply line in the same-station same-mother power supply structure, the length of the line, the failure rate of the switch and the number of switches;
[0059] Among them, the fault repair time of the target load point in the main power supply line in the same-station same-mother power supply structure is determined according to the failure rate of the line in the main power supply line of the target load point in the same-station same-mother power supply structure, the fault repair time of the line, the length of the line, the failure rate of the switch, the fault repair time of the switch and the number of switches, as well as the failure rate of the target load point in the main power supply line in the same-station same-mother power supply structure.
[0060] In an implementable manner, the third reliability of the target load point in the power transfer line is determined according to the failure rate and failure repair time of the target load point in the power transfer line.
[0061] Among them, Figure 2 As shown, the same station and same mother power supply structure, the common parts of which include substations and transformers.
[0062] It is understandable that the failure rate of a substation depends on many factors, including but not limited to equipment aging, maintenance status, environmental factors, etc. Usually, the failure rate can be obtained by statistical historical data, such as the ratio of the number of failures per year to the total operating time. Fault repair time: The fault repair time of a substation varies depending on the type and severity of the fault. Generally speaking, for simple faults, such as switch failure or small-scale leakage, the repair time may be short and can be completed within a few hours to a day. For more complex faults, such as internal transformer faults or large-scale power outages, the repair time may be longer, even taking days or more.
[0063] The failure rate of transformers is also affected by many factors, such as equipment quality, operating environment, load conditions, etc. Similar to substations, the failure rate of transformers can also be estimated by analyzing historical failure data.
[0064] Fault repair time: The time it takes to repair a transformer also depends on the nature and severity of the fault. A small fault may only take a few hours to repair, while a large fault may take days or even longer to repair, especially if it requires the replacement of important components or extensive repairs.
[0065] Optionally, in order to obtain accurate failure rate and fault repair time data, it is recommended to consult relevant historical records, maintenance logs or contact the equipment manufacturer for more specific information.
[0066] Obtaining the common fault rate and fault repair of the same station and mother power supply structure, including:
[0067] First, according to the obtained substation failure rate, transformer failure rate and bus failure rate in the common part of the same-station different-bus power supply structure, the failure rate λ of the common part of the same-station same-bus power supply structure is determined. res (n).
[0068] Specifically, the following formula (1) is used:
[0069] λ res (n) = λ s +λ m +λ t (1)
[0070] Among them, λs is the failure rate of the substation on the main power supply line, λm is the failure rate of the transformer on the main power supply line; λt is the failure rate of the busbar.
[0071] Secondly, according to the fault repair time of the substation in the common part of the same-station different-bus power supply structure, the fault rate of the substation, the fault repair time of the transformer, the fault rate of the transformer, the fault rate of the bus and the fault repair time of the bus, the fault time t of the common part of the same-station same-bus power supply structure is determined. res (n).
[0072] Specifically, the following formula (2) is used:
[0073]
[0074] Where t is the fault repair time of the substation, t m is the fault repair time of the transformer; t t is the fault repair time of the busbar;
[0075] Among them, the failure rate of the target load point in the power transfer line is determined according to the failure rate of the target load point in the power transfer line in the same station and the same mother power transfer structure, the length of the line, the failure rate of the switch and the number of switches.
[0076] Among them, the failure rate of the target load point in the main power supply line refers to the frequency of failure of the load point on the main line. This failure rate may be affected by many factors such as line aging, weather conditions, overload, external force damage, etc. In order to obtain accurate failure rate data, it is necessary to consult historical failure records, inspection reports and related operation data. Fault repair time: When a main power supply line fails, the time required from the discovery of the fault to the restoration of power supply is the fault repair time. The length of this time depends on the nature and severity of the fault and the response speed and efficiency of the maintenance team. In order to obtain this data, past maintenance records and work reports can be analyzed.
[0077] Obtain the failure rate and fault repair time of the target load point in the main power supply line in the same station and same mother-to-mother power supply structure, including:
[0078] According to the failure rate of the target load point in the main power supply line in the same station and same mother power supply structure, the line length, the failure rate of the switch and the number of switches, the failure rate λ of the target load point in the main power supply line in the same station and same mother power supply structure is determined. re1 (n).
[0079] Specifically, the following formula (3) is used:
[0080] λ re1 (n) = l l1 λ l +n b1 λ b (3)
[0081] Among them, λ l is the failure rate of the power supply line, b is the failure rate of the switch on the power supply line, l l1 is the line length of the target load point n-turn power supply line, n b1 The number of switches on the power supply line for the target load point n turns.
[0082] Further, according to the failure rate of the target load point in the main power supply line in the same-station same-mother transfer power supply structure, the line failure repair time, the line length, the switch failure rate, the switch failure repair time and the number of switches, and the failure rate of the target load point in the main power supply line in the same-station same-mother transfer power supply structure, the failure repair time t of the target load point in the main power supply line in the same-station same-mother transfer power supply structure is determined. re1 (n).
[0083] Specifically, the following formula (4) is used:
[0084] t re1 (n)=(l l1 λ l t l +n b1 λ b t b ) / λ re1 (n) (4)
[0085] Among them, t b is the failure rate of the power supply line;
[0086] Among them, the fault repair time of the target load point in the transfer power supply line in the same-station and same-mother transfer power supply structure is determined according to the failure rate of the line in the transfer power supply line of the target load point in the same-station and same-mother transfer power supply structure, the fault repair time of the line, the length of the line, the failure rate of the switch, the fault repair time of the switch and the number of switches, as well as the failure rate of the target load point in the transfer power supply line in the same-station and same-mother transfer power supply structure.
[0087] Furthermore, similar to the main power supply line, the failure rate of the target load point in the transfer power supply line also refers to the frequency of failures of the load point on the transfer power supply line. This failure rate may be affected by factors different from the main line, such as the maintenance status of the backup line, the frequency of use, etc. Similarly, it is necessary to estimate this failure rate through historical data and operation records. Fault repair time: When a fault occurs in the transfer power supply line, the time from detecting the fault to completing the repair and restoring power supply is the fault repair time of the transfer power supply line. This time may vary depending on the availability of the backup line, the allocation of maintenance resources, and the complexity of the fault. In order to obtain accurate data, it is necessary to review and analyze past fault repair cases.
[0088] Optionally, it may be necessary to comprehensively use historical data, operation records and maintenance reports to estimate the failure rate and failure repair time of the target load point in the main power supply line and the transfer power supply line.
[0089] Obtain the failure rate and fault repair time of the target load point in the power supply line, including:
[0090] According to the failure rate of the target load point in the transfer power supply line in the same-station and same-mother transfer power supply structure, the line length, the failure rate of the switch and the number of switches, the failure rate λ of the target load point in the transfer power supply line in the same-station and same-mother transfer power supply structure is determined. re2 (n).
[0091] Specifically, the following formula (5) is used:
[0092] λ re2 (n) = l l2 λ l +n b2 λ b (5)
[0093] Among them, l 12 is the line length of the target load point n on the power supply line 12, n b2 is the number of switches on the target load point n-turn power supply line 12; l is the failure rate of the line on the transfer power supply line; λb is the failure rate of the switch on the transfer power supply line.
[0094] In one implementable manner, the reliability of the same-station and same-mother power supply transfer structure is determined based on the first reliability, the second reliability and the third reliability, including: determining the power transfer success rate of the target load point based on the fault repair time and the failure rate and fault repair time of the target load point in the power transfer line; determining the failure rate and fault repair time of the target load point based on the power transfer success rate of the target load point, the failure rate and fault repair time of the common parts, and the failure rate and fault repair time of the target load point in the main power supply line; determining the reliability of the same-station and same-mother power supply transfer structure based on the failure rate and fault repair time of the target load point.
[0095] Optionally, the system failure rate can be obtained by combining the failure rates of each component. Since the components of the same mother-to-mother power supply structure at the same station are connected in series, the overall failure rate of the system will be the sum of the failure rates of each component. The average fault repair time of the system can be obtained by weighted averaging the fault repair time of each component, where the weight can be the probability of failure of each component.
[0096] Furthermore, using the system failure rate and mean time to repair, some key reliability indicators can be calculated, such as the mean time between failures (MTBF) and the mean time to repair (MTTR). These indicators will help to fully understand the reliability of the system.
[0097] The above-mentioned distribution network reliability assessment method for the same-station same-mother connection mode can realize fault assessment of each part in the same-station same-mother transfer power supply structure according to the failure rate and fault repair time of the common parts in the same-station same-mother transfer power supply structure, the failure rate and fault repair time of the target load point in the main power supply line in the same-station same-mother transfer power supply structure, and the failure rate and fault repair time of the target load point in the transfer power supply line. The comprehensiveness of the fault analysis improves the accuracy of the reliability analysis.
[0098] Further, according to the failure rate of the target load point in the transfer power supply line in the same-station same-mother transfer power supply structure, the line fault repair time, the line length, the switch failure rate, the switch failure repair time and the number of switches, and the failure rate of the target load point in the transfer power supply line in the same-station same-mother transfer power supply structure, the fault repair time t of the target load point in the transfer power supply line in the same-station same-mother transfer power supply structure is determined. re2 (n).
[0099] Specifically, the following formula (6) is used:
[0100] t re2 (n)=(l l2 λ l t l +n b2 λ b t b ) / λre2 (n) (6)
[0101] Among them, t1 is the failure rate of the substation on the power supply line, t b is the failure rate of the power supply line.
[0102] In one embodiment, the reliability of the same-station same-mother power supply structure is determined based on the failure rate and fault repair time of the common part, the failure rate and fault repair time of the target load point in the main power supply line, and the failure rate and fault repair time of the target load point in the power supply transfer line, including:
[0103] First, according to the fault repair time, the failure rate of the target load point in the power transfer line and the fault repair time, the transfer success rate p of the target load point is determined. t .
[0104] Specifically, the following formula (7) is used:
[0105]
[0106] Secondly, according to the transfer success rate of the target load point, the failure rate and fault repair time of the common parts, the failure rate and fault repair time of the target load point in the main power supply line, the failure rate λ(n) and fault repair time t(n) of the target load point are determined.
[0107] Specifically, the failure rate λ(n) of the target load point is calculated using the following formula (8):
[0108] λ(n)=λ res +λ re1 (8)
[0109] The failure rate λ(n) of the target load point is calculated using the following formula (9):
[0110] t(n)=(λ res t res +λ re1 (p t t zg +(1-p t )t re1 )) / λ(n) (9)
[0111] Furthermore, if the reliability of the same-station same-mother power supply structure is determined based on the failure rate and failure repair time of the target load point, it includes:
[0112] According to the failure rate of each target load point, determine the average failure rate in the same station and the same mother power supply structure
[0113] Determine the average failure time of the same station and the same mother-to-mother power supply structure based on the average failure time of each target load point
[0114] According to the average failure rate and average failure time of the same-station same-mother power supply structure, the reliability R of the same-station same-mother power supply structure is determined. sys .
[0115] Specifically, calculate the average failure rate in the same station and the same mother power supply structure The following formula (10) is used:
[0116]
[0117] Specifically, calculate the average failure rate in the same station and the same mother power supply structure The following formula (11) is used:
[0118]
[0119] Specifically, calculate the average failure rate R in the same station and same mother power supply structure sys , using the following formula (12):
[0120]
[0121] It should be understood that, although the steps in the flowcharts involved in the above embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above embodiments may include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.
[0122] Based on the same inventive concept, the embodiment of the present application also provides a distribution network reliability assessment device for the same-station same-mother connection mode for implementing the distribution network reliability assessment method for the same-station same-mother connection mode involved above. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme recorded in the above method, so the specific limitations in one or more embodiments of the distribution network reliability assessment device for the same-station same-mother connection mode provided below can refer to the limitations of the distribution network reliability assessment method for the same-station same-mother connection mode above, and will not be repeated here.
[0123] In an exemplary embodiment, a distribution network reliability assessment device in a same-station same-mother connection mode is provided, comprising:
[0124] A branch acquisition module is used to obtain the first reliability corresponding to the common part in the same-station and same-mother power supply structure, the second reliability corresponding to the target load point in the main power supply line in the same-station and same-mother power supply structure, and the third reliability of the target load point in the power supply line;
[0125] The comprehensive evaluation module is used to determine the reliability of the same-station and same-mother power supply structure based on the first reliability, the second reliability and the third reliability.
[0126] Each module in the above-mentioned distribution network reliability assessment device with the same station and same mother connection mode can be implemented in whole or in part by software, hardware and their combination. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.
[0127] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, an artificial intelligence (AI) processor, etc., but are not limited to this.
[0128] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.
[0129] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.
Claims
1. A method for evaluating the reliability of a distribution network with a same-station and same-mother connection, characterized in that: The method comprises: Obtaining a first reliability corresponding to a common part in a same-station same-mother power supply structure, a second reliability corresponding to a target load point in the same-station same-mother power supply structure in a main power supply line, and a third reliability of the target load point in a power supply transfer line; The reliability of the same-station same-mother power supply structure is determined based on the first reliability, the second reliability and the third reliability.
2. The method according to claim 1, characterized in that The common parts include at least one of a transformer, a substation, a busbar system, a disconnector, a circuit breaker, a current transformer, a voltage transformer, a lightning arrester and an overvoltage protection device.
3. The method according to claim 1, characterized in that The obtaining of the second reliability corresponding to the target load point in the same-station same-mother power supply structure in the main power supply line includes: In the same-station and same-mother power supply structure, a fault tree is constructed for the power supply path of the target load point in the main power supply line; Based on the fault analysis tree, various fault modes that lead to power outage at the load point are analyzed; According to the occurrence probability of each failure mode, the second reliability corresponding to the target load point in the same-station and same-mother power supply structure in the main power supply line is determined.
4. The method according to claim 1, characterized in that: The obtaining of the third reliability of the target load point in the power transfer line includes: Construct a Bayesian network model of the target load point in the power transfer line in the same-station and same-mother power transfer structure; wherein the Bayesian network model should include each component in the power transfer line and its failure probability and the impact of the failure on the power supply of the target load point; Based on the Bayesian network model, the third reliability of the target load point in the power supply line.
5. The method according to claim 1, characterized in that: The determining, according to the first reliability, the second reliability and the third reliability, the reliability of the same-station same-mother power supply structure includes: The first reliability, the second reliability and the third reliability are weighted according to the weight coefficients corresponding to the first reliability, the second reliability and the third reliability respectively, so as to obtain the reliability of the same-station same-mother power supply structure.
6. The method according to claim 2, characterized in that If the common part includes a transformer and a substation, the first reliability is determined according to the failure rate and fault repair time corresponding to the common part in the same-station and same-mother power supply structure.
7. The method according to claim 6, characterized in that The second reliability corresponding to the target load point in the same-station same-mother power supply structure in the main power supply line is determined according to the failure rate and failure repair time of the target load point in the same-station same-mother power supply structure in the main power supply line; The failure rate of the target load point in the main power supply line in the same-station same-mother power supply structure is determined according to the failure rate of the target load point in the main power supply line in the same-station same-mother power supply structure, the length of the line, the failure rate of the switch and the number of switches; Among them, the fault repair time of the target load point in the main power supply line in the same-station same-mother power supply structure is determined according to the failure rate of the target load point in the main power supply line in the same-station same-mother power supply structure, the fault repair time of the line, the length of the line, the failure rate of the switch, the fault repair time of the switch and the number of switches, as well as the failure rate of the target load point in the main power supply line in the same-station same-mother power supply structure.
8. The method according to claim 7, characterized in that The third reliability of the target load point in the power transfer line is determined according to the failure rate and failure repair time of the target load point in the power transfer line; The failure rate of the target load point in the power transfer line is determined according to the failure rate of the target load point in the power transfer line in the same-station and same-mother power transfer structure, the length of the line, the failure rate of the switch and the number of switches; Among them, the fault repair time of the target load point in the transfer power supply line in the same-station same-mother transfer power supply structure is determined according to the failure rate of the line in the transfer power supply line of the target load point in the same-station same-mother transfer power supply structure, the fault repair time of the line, the length of the line, the failure rate of the switch, the fault repair time of the switch and the number of switches, as well as the failure rate of the target load point in the transfer power supply line in the same-station same-mother transfer power supply structure.
9. The method according to claim 8, characterized in that The determining, according to the first reliability, the second reliability and the third reliability, the reliability of the same-station same-mother power supply structure includes: Determine the power transfer success rate of the target load point according to the fault repair time and the fault rate and fault repair time of the target load point in the power transfer line; Determine the failure rate and fault repair time of the target load point according to the transfer success rate of the target load point, the failure rate and fault repair time of the common part, and the failure rate and fault repair time of the target load point in the main power supply line; The reliability of the same-station same-mother power supply structure is determined based on the failure rate and failure repair time of the target load point.
10. A distribution network reliability assessment device with same-station and same-mother connection, characterized in that: The device comprises: A branch acquisition module, used to obtain a first reliability corresponding to a common part in a same-station same-mother transfer power supply structure, a second reliability corresponding to a target load point in the same-station same-mother transfer power supply structure in a main power supply line, and a third reliability of the target load point in a transfer power supply line; A comprehensive evaluation module is used to determine the reliability of the same-station same-mother power supply structure based on the first reliability, the second reliability and the third reliability.