A method and system for risk assessment of a power grid equipment safety state

Abstract

The application relates to the technical field of power grid risk assessment, and discloses a power grid equipment safety state risk assessment method and system, which obtains attribute information and operation information of all user sides in a distribution network, constructs a weighted undirected graph according to a topological connection structure between all equipment nodes and the user sides in the distribution network, performs topological analysis on the user side with the highest importance level in the weighted undirected graph, obtains a corresponding power supply path, determines a power supply source configuration qualification rate, a relay protection correct action rate, an annual average power-off time and a voltage qualification rate of all user sides with the highest importance level, performs weighted calculation, obtains an equipment operation state safety value, compares the equipment operation state safety value with a preset state safety threshold value, determines a risk situation of the equipment safety state of the user side with the highest importance level, and improves the accuracy and reliability of the risk assessment of the power equipment safety state of important users.

Description

Technical Field

[0001] This invention relates to the field of power grid risk assessment technology, and in particular to a method and system for risk assessment of the safety status of power grid equipment. Background Technology

[0002] To achieve inherent safety in power equipment and facilities, firstly, the equipment and facilities should have high reliability, good safety characteristics, and a complete safety protection system, so that even if human error or equipment accident occurs, the safety of personnel and equipment can be ensured.

[0003] Due to the complex power environment, low level of mechanization, and high labor intensity of workers, the planning and construction of an inherently safe power grid can shift the control of safety risks to the forefront and prevent them at the source, thereby improving the quality and health of equipment and facilities connected to the grid and achieving inherent safety of things.

[0004] Meanwhile, the safety status of the power grid equipment of important users in the power grid is particularly important. However, the current risk assessment of the safety status of power equipment of important users is not accurate enough and has poor reliability, resulting in insufficient power supply capacity to important users. Summary of the Invention

[0005] This invention provides a method and system for risk assessment of the safety status of power grid equipment, which solves the technical problems of inaccurate and unreliable risk assessment of the safety status of power equipment for important users.

[0006] In view of this, the first aspect of the present invention provides a risk assessment method for the safety status of power grid equipment, comprising the following steps:

[0007] Obtain attribute information and operation information of all users in the distribution network. The attribute information includes importance level and user meter address, and the operation information includes voltage data and power outage time.

[0008] Construct a weighted undirected graph based on the topological connection structure between all equipment nodes and the user side in the distribution network;

[0009] The corresponding power supply is matched in the preset meter database based on the user's meter address;

[0010] Based on the breadth-first search algorithm, topology analysis is performed on the user side with the highest importance level in the weighted undirected graph to obtain the corresponding matching power supply, and the corresponding power supply path is obtained. The power supply path includes the power supply, line, sectionalizing switch and relay protection device.

[0011] Calculate the power ratio between the output power of the power supply and its rated power, and determine whether the power ratio is greater than the load rate threshold of the power supply path. If the power ratio is greater than the load rate threshold of the power supply path, the power supply configuration of the user side with the highest importance level is determined to be unqualified, thereby determining the qualification rate of the power supply configuration of all users with the highest importance level.

[0012] Obtain the FTU parameters of the relay protection equipment, calculate the correct operating rate of the relay protection based on the FTU parameters of the relay protection equipment, and thus determine the correct operating rate of the relay protection on the user side with the highest importance level.

[0013] The annual average outage time and voltage compliance rate of all users with the highest importance level are determined based on the operational information of the users with the highest importance level.

[0014] The power supply configuration qualification rate, relay protection correct operation rate, annual average power outage time and voltage qualification rate of all users with the highest importance level are standardized and weighted to obtain the equipment operation status safety value of all users with the highest importance level.

[0015] The device's operational status safety value is compared with a preset status safety threshold. If the device's operational status safety value is greater than the preset status safety threshold, the device on the user side with the highest importance level is determined to be in a reliable state. If the device's operational status safety value is not greater than the preset status safety threshold, the device on the user side with the highest importance level is determined to be in a risky state.

[0016] Preferably, the step of constructing a weighted undirected graph based on the topological connection structure between all equipment nodes and the user side in the distribution network specifically includes:

[0017] Construct an undirected graph based on the topological connection structure between all equipment nodes and the user side in the distribution network;

[0018] A weighted undirected graph is constructed by using the electrical distances between all device nodes as the weights of the edges in the undirected graph.

[0019] Preferably, the method further includes:

[0020] The power supply path is divided into multiple sections according to the segmented switch, and the maximum current value and rated current value corresponding to each section are obtained.

[0021] Calculate the ratio between the maximum current value and the rated current value of each section as the load rate of the corresponding section, and select the minimum load rate among all sections as the load rate threshold of the power supply path.

[0022] Preferably, based on the breadth-first search algorithm, the step of performing topology analysis on the user side with the highest importance level in the weighted undirected graph to obtain the corresponding power supply path, wherein the power supply path includes the power supply, line, sectionalizing switch and relay protection equipment, specifically includes:

[0023] Taking the user side with the highest importance level as the topology starting point and the power supply corresponding to the user side with the highest importance level as the topology ending point, based on the breadth-first search algorithm, topology analysis is performed from the topology starting point upwards in the weighted undirected graph to determine the nodes associated with the power supply of the topology starting point until the topology ending point, thus obtaining the power supply path. The power supply path includes the power supply, line, sectionalizing switch and relay protection equipment.

[0024] Preferably, the step of determining the annual average outage time and voltage compliance rate for all users with the highest importance level based on their operational information specifically includes:

[0025] The average outage time per year is calculated based on the ratio of the outage time of the user with the highest importance level to the total operating time per year.

[0026] Voltage data from the user side with the highest importance level will be collected at a preset frequency.

[0027] Perform a fast Fourier transform on the voltage data to obtain frequency domain voltage information;

[0028] The number of voltage loss times, overvoltage times, and voltage imbalance times within a preset time period are determined based on the frequency domain voltage information.

[0029] By statistically analyzing the number of voltage loss, the number of overvoltage, and the number of voltage imbalances, the total number of voltage failures is obtained, and the proportion of the total number of voltage failures in all sample points within the frequency domain voltage information is calculated.

[0030] The voltage pass rate is calculated by averaging the percentage of the total number of voltage failures on the user side with the highest importance level.

[0031] Secondly, the present invention also provides a risk assessment system for the safety status of power grid equipment, comprising:

[0032] The information acquisition module is used to acquire attribute information and operation information of all users in the distribution network. The attribute information includes importance level and user meter address, and the operation information includes voltage data and power outage time.

[0033] A weighted undirected graph construction module is used to construct a weighted undirected graph based on the topological connection structure between all equipment nodes and the user side in the distribution network.

[0034] The power matching module is used to match the corresponding power supply in a preset meter database based on the user's meter address.

[0035] The topology analysis module is used to perform topology analysis on the user side with the highest importance level in the weighted undirected graph based on the breadth-first search algorithm, to obtain the corresponding matching power supply, and the corresponding power supply path includes the power supply, line, sectionalizing switch and relay protection device.

[0036] The power configuration evaluation module is used to calculate the power ratio between the output power of the power supply and its rated power, and to determine whether the power ratio is greater than the load rate threshold of the power supply path. If the power ratio is greater than the load rate threshold of the power supply path, the power supply configuration of the user side with the highest importance level is determined to be unqualified, thereby determining the qualification rate of the power supply configuration of all users with the highest importance level.

[0037] The relay protection assessment module is used to obtain the FTU parameters of the relay protection equipment, calculate the correct operation rate of the relay protection based on the FTU parameters of the relay protection equipment, and thus determine the correct operation rate of the relay protection on the user side with the highest importance level.

[0038] The voltage assessment module is used to determine the annual average outage time and voltage compliance rate for all users with the highest importance level based on their operational information.

[0039] The operation status calculation module is used to standardize the power supply configuration qualification rate, relay protection correct operation rate, annual average power outage time and voltage qualification rate of all users with the highest importance level, and perform weighted calculations to obtain the equipment operation status safety value of all users with the highest importance level.

[0040] The operation status assessment module is used to compare the device operation status safety value with a preset status safety threshold. If the device operation status safety value is greater than the preset status safety threshold, the device on the user side with the highest importance level is determined to be in a reliable state. If the device operation status safety value is not greater than the preset status safety threshold, the device on the user side with the highest importance level is determined to be in a risky state.

[0041] Preferably, the weighted undirected graph construction module specifically includes:

[0042] The undirected graph construction module is used to construct an undirected graph based on the topological connection structure between all equipment nodes and the user side in the power distribution network.

[0043] The weight module is used to construct a weighted undirected graph by using the electrical distance between all device nodes as the weight of the edges of the undirected graph.

[0044] Preferably, the system further includes:

[0045] The segmentation module is used to divide the power supply path into multiple segments according to the segmentation switch, and obtain the maximum current value and rated current value corresponding to each segment.

[0046] The load rate filtering module is used to calculate the current ratio between the maximum current value and the rated current value of each segment as the load rate of the corresponding segment, and to filter out the minimum load rate among all segments as the load rate threshold of the power supply path.

[0047] Preferably, the topology analysis module is specifically used to perform topology analysis from the topology starting point upwards in the weighted undirected graph, based on the breadth-first search algorithm, with the user side with the highest importance level as the topology starting point and the power supply corresponding to the user side with the highest importance level as the topology ending point, to determine the nodes associated with the power supply of the topology starting point up to the topology ending point, and obtain the power supply path, which includes the power supply, line, sectionalizing switch and relay protection equipment.

[0048] Preferably, the voltage evaluation module specifically includes:

[0049] The power outage time calculation module is used to calculate the average power outage time within the year based on the ratio of the power outage time of the user with the highest importance level to the total operating time within the year.

[0050] The voltage acquisition module is used to acquire voltage data from the user side with the highest importance level at a preset frequency.

[0051] The conversion module is used to perform a fast Fourier transform on the voltage data to obtain frequency domain voltage information;

[0052] The voltage failure determination module is used to determine the number of voltage loss times, overvoltage times, and voltage imbalance times within a preset time period based on the frequency domain voltage information.

[0053] The voltage failure calculation module is used to obtain the total number of voltage failures by statistically analyzing the number of voltage loss, the number of overvoltage, and the number of voltage imbalances, and to calculate the proportion of the total number of voltage failures in all sample points within the frequency domain voltage information.

[0054] The voltage pass rate calculation module is used to calculate the average percentage of the total number of voltage failures on all user sides with the highest importance level, and thus obtain the voltage pass rate.

[0055] As can be seen from the above technical solutions, the present invention has the following advantages:

[0056] This invention acquires attribute and operational information of all user-side components in a power distribution network. Based on the topological connections between all equipment nodes and user-side components, a weighted undirected graph is constructed. Using a breadth-first search algorithm, topological analysis is performed on the user-side component with the highest importance level within the weighted undirected graph to obtain the corresponding power supply path. Furthermore, by determining the power supply configuration qualification rate, relay protection correct operation rate, average annual outage time, and voltage qualification rate of all user-side components with the highest importance level and performing weighted calculations, a safety value for the equipment's operating status is obtained. Based on the comparison between this safety value and a preset safety threshold, the risk of the equipment's safety status on the user-side component with the highest importance level is determined, thereby improving the accuracy and reliability of risk assessment for the power equipment safety status of important users. Attached Figure Description

[0057] Figure 1 A flowchart illustrating a risk assessment method for the safety status of power grid equipment provided in an embodiment of the present invention;

[0058] Figure 2 This is a schematic diagram of the structure of a risk assessment system for the safety status of power grid equipment provided in an embodiment of the present invention. Detailed Implementation

[0059] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0060] For easier understanding, please refer to Figure 1 The present invention provides a risk assessment method for the safety status of power grid equipment, comprising the following steps:

[0061] 101. Obtain attribute information and operation information for all user sides in the distribution network. Attribute information includes importance level and user meter address, and operation information includes voltage data and power outage time.

[0062] The importance level is a pre-defined importance level for the user side, used to evaluate the importance of the user side, and can be divided into high, medium and low.

[0063] 102. Construct a weighted undirected graph based on the topological connection structure between all equipment nodes and the user side in the distribution network.

[0064] The topology connection structure between all equipment nodes and the user side in the distribution network can be obtained based on the power grid GIS system. The topology connection structure includes the topology connection structure between each equipment node and the topology connection structure between the equipment node and the user side.

[0065] 103. Match the corresponding power supply to the user's meter address in the preset meter database. The preset meter database contains the mapping relationship between user meter addresses and power supplies, which can be substations or transformers.

[0066] 104. Based on the breadth-first search algorithm, perform topology analysis on the user side with the highest importance level in the weighted undirected graph to find the corresponding matching power supply, and obtain the corresponding power supply path. The power supply path includes the power supply, line, sectionalizing switch and relay protection equipment.

[0067] Breadth-first search (BFS) systematically expands and examines all nodes in a weighted undirected graph to find the result. The BFS process is as follows: before the search begins, all nodes in the weighted undirected graph are white. As the search progresses, the nodes gradually turn gray, and then black. When a node is encountered for the first time during the search, we say that the node has been found, and at this point, the node becomes a non-white node. Therefore, both gray and black nodes have been found, but the BFS distinguishes between them to ensure that the search is performed in a breadth-first manner.

[0068] Meanwhile, by using a breadth-first search algorithm to perform topology analysis on the user side with the highest importance level in the weighted undirected graph to the corresponding matching power supply, the resulting power supply path is the power supply path from the power supply to the corresponding user side.

[0069] 105. Calculate the power ratio between the output power of the power supply and its rated power, and determine whether the power ratio is greater than the load rate threshold of the power supply path. If the power ratio is greater than the load rate threshold of the power supply path, the power supply configuration of the user side with the highest importance level is deemed unqualified, thereby determining the qualification rate of the power supply configuration of all users with the highest importance level.

[0070] If the power ratio is greater than the load rate threshold of the power supply path, it indicates that there is overload behavior and the power supply configuration is unqualified. If the power ratio is not greater than the load rate threshold of the power supply path, it indicates that the power supply configuration is qualified.

[0071] 106. Obtain the FTU parameters of the relay protection equipment, calculate the correct operating rate of the relay protection based on the FTU parameters, and thus determine the correct operating rate of the relay protection on the user side with the highest importance level.

[0072] The FTU parameters include the relay protection operation status and the relay protection correct operation rate. By statistically analyzing the relay protection correct operation rate of the user-side relay protection equipment with the highest importance level, the correct operation rate of all user-side relay protection with the highest importance level can be determined.

[0073] 107. Determine the annual average outage time and voltage qualification rate for all users with the highest importance level based on their operational information.

[0074] Among them, the average outage time per year can be used to calculate the average outage time for low-voltage and medium-voltage users, and the voltage qualification rate can be used to calculate the overall voltage qualification rate.

[0075] 108. Standardize the power supply configuration qualification rate, relay protection correct operation rate, annual average power outage time and voltage qualification rate of all users with the highest importance level, and perform weighted calculations to obtain the equipment operating status safety value of all users with the highest importance level.

[0076] The weights corresponding to the power supply configuration qualification rate, relay protection correct operation rate, average annual power outage time and voltage qualification rate on the user side can be set by empirical values ​​or determined by the analytic hierarchy process.

[0077] 109. Compare the equipment operating status safety value with the preset status safety threshold. If the equipment operating status safety value is greater than the preset status safety threshold, the equipment on the user side with the highest importance level is determined to be in a reliable state. If the equipment operating status safety value is not greater than the preset status safety threshold, the equipment on the user side with the highest importance level is determined to be in a risky state.

[0078] The system can also set risk levels as low, medium, and high, and set corresponding risk level thresholds for multiple risk levels. By comparing multiple risk level thresholds with the safety values ​​of the equipment's operating status, the risk level of the equipment's safety status on the user side can be determined.

[0079] It should be noted that this invention provides a risk assessment method for the safety status of power grid equipment. By acquiring the attribute and operational information of all user-side components in the distribution network, a weighted undirected graph is constructed based on the topological connection structure between all equipment nodes and user-side components in the distribution network. Based on a breadth-first search algorithm, topological analysis is performed on the user-side component with the highest importance level in the weighted undirected graph to obtain the corresponding power supply path. Furthermore, by determining the power supply configuration qualification rate, relay protection correct operation rate, average annual power outage time, and voltage qualification rate of all user-side components with the highest importance level and performing weighted calculations, a safety value for the equipment operating status is obtained. Based on the comparison result between the equipment operating status safety value and a preset safety threshold, the risk situation of the equipment safety status of the user-side component with the highest importance level is determined, thereby improving the accuracy and reliability of the risk assessment of the safety status of power equipment for important users.

[0080] In one specific embodiment, step 102 specifically includes:

[0081] 1021. Construct an undirected graph based on the topological connection structure between all equipment nodes and the user side in the distribution network.

[0082] 1022. Construct a weighted undirected graph by using the electrical distance between all device nodes as the weight of the edges in the undirected graph.

[0083] The electrical distance between device nodes should be between different device nodes.

[0084] In one specific embodiment, the method further includes:

[0085] 111. Divide the power supply path into multiple sections according to the sectionalizing switch, and obtain the maximum current value and rated current value corresponding to each section.

[0086] The maximum current value of the section can be determined by the maximum current value that has flowed through it in history, and the rated current value is the overcurrent protection current of the relay protection equipment in the section.

[0087] 112. Calculate the current ratio between the maximum current value and the rated current value of each section as the load rate of the corresponding section, and select the minimum load rate among all sections as the load rate threshold of the power supply path.

[0088] It is understandable that the minimum load rate in all sections is used as the load rate threshold for the power supply path. If the power supply exceeds this load rate threshold, it is determined that there is an overload, thereby improving sensitivity.

[0089] In one specific embodiment, step 104 specifically includes:

[0090] Taking the user side with the highest importance level as the topology starting point and the power supply corresponding to the user side with the highest importance level as the topology ending point, based on the breadth-first search algorithm, topology analysis is performed from the topology starting point upwards in the weighted undirected graph to determine the nodes associated with the power supply of the topology starting point until the topology ending point, thus obtaining the power supply path. The power supply path includes the power supply, line, sectionalizing switch and relay protection equipment.

[0091] In one specific embodiment, step 107 specifically includes:

[0092] 1071. Calculate the average outage time per year based on the ratio of the outage time of the user with the highest importance level to the total operating time per year.

[0093] 1072. Collect voltage data from the user side with the highest importance level at a preset frequency.

[0094] 1073. Perform a fast Fourier transform on the voltage data to obtain frequency domain voltage information.

[0095] Among them, frequency domain voltage information can be characterized as the relationship between voltage value and frequency, and each frequency point is a corresponding sampling point.

[0096] 1074. Determine the number of voltage loss, overvoltage, and voltage imbalance times within a preset time period based on the frequency domain voltage information.

[0097] Among them, the three situations of undervoltage, overvoltage, and voltage imbalance can be easily identified by observing the changes in voltage values.

[0098] 1075. By statistically analyzing the number of voltage failures, overvoltages, and voltage imbalances, the total number of voltage failures is obtained, and the proportion of the total number of voltage failures in all sample points within the frequency domain voltage information is calculated.

[0099] 1076. The voltage pass rate is obtained by averaging the percentage of the total number of voltage failures on the user side with the highest importance level.

[0100] The above is a detailed description of an embodiment of a risk assessment method for the safety status of power grid equipment provided by the present invention. The following is a detailed description of an embodiment of a risk assessment system for the safety status of power grid equipment provided by the present invention.

[0101] For easier understanding, please refer to Figure 2 The present invention also provides a risk assessment system for the safety status of power grid equipment, comprising:

[0102] The information acquisition module 100 is used to acquire attribute information and operation information of all users in the distribution network. The attribute information includes importance level and user meter address, and the operation information includes voltage data and power outage time.

[0103] The weighted undirected graph construction module 200 is used to construct a weighted undirected graph based on the topological connection structure between all equipment nodes and the user side in the distribution network.

[0104] The power matching module 300 is used to match the corresponding power supply in a preset electricity meter database based on the user's electricity meter address.

[0105] The topology analysis module 400 is used to perform topology analysis on the user side with the highest importance level in the weighted undirected graph based on the breadth-first search algorithm, to obtain the corresponding power supply path, which includes the power supply, line, sectionalizing switch and relay protection equipment.

[0106] The power configuration evaluation module 500 is used to calculate the power ratio between the output power of the power supply and its rated power, and to determine whether the power ratio is greater than the load rate threshold of the power supply path. If the power ratio is greater than the load rate threshold of the power supply path, the power supply configuration of the user side with the highest importance level is determined to be unqualified, thereby determining the qualification rate of the power supply configuration of all users with the highest importance level.

[0107] The relay protection assessment module 600 is used to obtain the FTU parameters of the relay protection equipment, calculate the correct operating rate of the relay protection based on the FTU parameters of the relay protection equipment, and thus determine the correct operating rate of the relay protection on the user side with the highest importance level.

[0108] Voltage assessment module 700 is used to determine the annual average outage time and voltage compliance rate of all users with the highest importance level based on the operation information of the users with the highest importance level.

[0109] The operation status calculation module 800 is used to standardize the power supply configuration qualification rate, relay protection correct operation rate, annual average power outage time and voltage qualification rate of all users with the highest importance level, and perform weighted calculations to obtain the equipment operation status safety value of all users with the highest importance level.

[0110] The operation status assessment module 900 is used to compare the device operation status safety value with the preset status safety threshold. If the device operation status safety value is greater than the preset status safety threshold, the device on the user side with the highest importance level is determined to be in a reliable state. If the device operation status safety value is not greater than the preset status safety threshold, the device on the user side with the highest importance level is determined to be in a risky state.

[0111] In one specific embodiment, the weighted undirected graph construction module specifically includes:

[0112] The undirected graph construction module is used to construct an undirected graph based on the topological connection structure between all equipment nodes and the user side in the power distribution network.

[0113] The weight module is used to construct a weighted undirected graph by using the electrical distance between all device nodes as the weight of the edges of the undirected graph.

[0114] In one specific embodiment, the system further includes:

[0115] The segmentation module is used to divide the power supply path into multiple segments according to the segment switch, and obtain the maximum current value and rated current value corresponding to each segment.

[0116] The load rate filtering module is used to calculate the current ratio between the maximum current value and the rated current value of each segment as the load rate of the corresponding segment, and to filter out the minimum load rate among all segments as the load rate threshold of the power supply path.

[0117] In one specific embodiment, the topology analysis module is specifically used to perform topology analysis from the topology starting point upwards in a weighted undirected graph, based on a breadth-first search algorithm, with the user side with the highest importance level as the topology starting point and the power supply corresponding to the user side with the highest importance level as the topology ending point, to determine the nodes associated with the power supply of the topology starting point up to the topology ending point, and obtain the power supply path. The power supply path includes the power supply, line, sectionalizing switch and relay protection equipment.

[0118] In one specific embodiment, the voltage evaluation module specifically includes:

[0119] The power outage time calculation module is used to calculate the average power outage time within the year based on the ratio of the power outage time of the user with the highest importance level to the total operating time within the year.

[0120] The voltage acquisition module is used to acquire voltage data from the user side with the highest importance level at a preset frequency.

[0121] The conversion module is used to perform fast Fourier transform on voltage data to obtain frequency domain voltage information;

[0122] The voltage failure determination module is used to determine the number of voltage loss, overvoltage, and voltage imbalance times within a preset time period based on frequency domain voltage information.

[0123] The voltage failure calculation module is used to obtain the total number of voltage failures by statistically analyzing the number of voltage loss, overvoltage, and voltage imbalance, and to calculate the proportion of the total number of voltage failures in all sample points within the frequency domain voltage information.

[0124] The voltage pass rate calculation module is used to calculate the average percentage of the total number of voltage failures on all user sides with the highest importance level, and thus obtain the voltage pass rate.

[0125] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working process of the system described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0126] In the several embodiments provided by this invention, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0127] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0128] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0129] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A risk assessment method for the safety status of power grid equipment, characterized in that, Includes the following steps: Obtain attribute information and operation information of all users in the distribution network. The attribute information includes importance level and user meter address, and the operation information includes voltage data and power outage time. Construct a weighted undirected graph based on the topological connection structure between all equipment nodes and the user side in the distribution network; The corresponding power supply is matched in the preset meter database based on the user's meter address; Based on the breadth-first search algorithm, topology analysis is performed on the user side with the highest importance level in the weighted undirected graph to obtain the corresponding matching power supply, and the corresponding power supply path is obtained. The power supply path includes the power supply, line, sectionalizing switch and relay protection device. Calculate the power ratio between the output power of the power supply and its rated power, and determine whether the power ratio is greater than the load rate threshold of the power supply path. If the power ratio is greater than the load rate threshold of the power supply path, the power supply configuration of the user side with the highest importance level is determined to be unqualified, thereby determining the qualification rate of the power supply configuration of all users with the highest importance level. Obtain the FTU parameters of the relay protection equipment, calculate the correct operating rate of the relay protection based on the FTU parameters of the relay protection equipment, and thus determine the correct operating rate of the relay protection on the user side with the highest importance level. The annual average outage time and voltage compliance rate of all users with the highest importance level are determined based on the operational information of the users with the highest importance level. The power supply configuration qualification rate, relay protection correct operation rate, annual average power outage time and voltage qualification rate of all users with the highest importance level are standardized and weighted to obtain the equipment operation status safety value of all users with the highest importance level. The device's operational status safety value is compared with a preset status safety threshold. If the device's operational status safety value is greater than the preset status safety threshold, the device on the user side with the highest importance level is determined to be in a reliable state. If the device's operational status safety value is not greater than the preset status safety threshold, the device on the user side with the highest importance level is determined to be in a risky state.

2. The risk assessment method for the safety status of power grid equipment according to claim 1, characterized in that, The specific steps for constructing a weighted undirected graph based on the topological connection structure between all equipment nodes and the user side in the distribution network include: Construct an undirected graph based on the topological connection structure between all equipment nodes and the user side in the distribution network; A weighted undirected graph is constructed by using the electrical distances between all device nodes as the weights of the edges in the undirected graph.

3. The risk assessment method for the safety status of power grid equipment according to claim 1, characterized in that, Also includes: The power supply path is divided into multiple sections according to the segmented switch, and the maximum current value and rated current value corresponding to each section are obtained. Calculate the ratio between the maximum current value and the rated current value of each section as the load rate of the corresponding section, and select the minimum load rate among all sections as the load rate threshold of the power supply path.

4. The risk assessment method for the safety status of power grid equipment according to claim 1, characterized in that, Based on the breadth-first search algorithm, topology analysis is performed on the user side with the highest importance level in the weighted undirected graph to find the corresponding matching power supply, thereby obtaining the corresponding power supply path. The power supply path includes the power supply, line, sectionalizing switch, and relay protection equipment. The specific steps include: Taking the user side with the highest importance level as the topology starting point and the power supply corresponding to the user side with the highest importance level as the topology ending point, based on the breadth-first search algorithm, topology analysis is performed from the topology starting point upwards in the weighted undirected graph to determine the nodes associated with the power supply of the topology starting point until the topology ending point, thus obtaining the power supply path. The power supply path includes the power supply, line, sectionalizing switch and relay protection equipment.

5. The risk assessment method for the safety status of power grid equipment according to claim 1, characterized in that, The steps for determining the annual average outage time and voltage compliance rate for all users with the highest importance level based on their operational information include: The average outage time per year is calculated based on the ratio of the outage time of the user with the highest importance level to the total operating time per year. Voltage data from the user side with the highest importance level will be collected at a preset frequency. Perform a fast Fourier transform on the voltage data to obtain frequency domain voltage information; The number of voltage loss times, overvoltage times, and voltage imbalance times within a preset time period are determined based on the frequency domain voltage information. By statistically analyzing the number of voltage loss events, the number of overvoltage events, and the number of voltage imbalance events, the total number of voltage failures is obtained, and the proportion of the total number of voltage failures in all sample points within the frequency domain voltage information is calculated. The voltage pass rate is calculated by averaging the percentage of the total number of voltage failures on the user side with the highest importance level.

6. A risk assessment system for the safety status of power grid equipment, characterized in that, include: The information acquisition module is used to acquire attribute information and operation information of all users in the distribution network. The attribute information includes importance level and user meter address, and the operation information includes voltage data and power outage time. A weighted undirected graph construction module is used to construct a weighted undirected graph based on the topological connection structure between all equipment nodes and the user side in the distribution network. The power matching module is used to match the corresponding power supply in a preset meter database based on the user's meter address. The topology analysis module is used to perform topology analysis on the user side with the highest importance level in the weighted undirected graph based on the breadth-first search algorithm, to obtain the corresponding matching power supply, and the corresponding power supply path includes the power supply, line, sectionalizing switch and relay protection device. The power configuration evaluation module is used to calculate the power ratio between the output power of the power supply and its rated power, and to determine whether the power ratio is greater than the load rate threshold of the power supply path. If the power ratio is greater than the load rate threshold of the power supply path, the power supply configuration of the user side with the highest importance level is determined to be unqualified, thereby determining the qualification rate of the power supply configuration of all users with the highest importance level. The relay protection assessment module is used to obtain the FTU parameters of the relay protection equipment, calculate the correct operation rate of the relay protection based on the FTU parameters of the relay protection equipment, and thus determine the correct operation rate of the relay protection on the user side with the highest importance level. The voltage assessment module is used to determine the annual average outage time and voltage compliance rate for all users with the highest importance level based on their operational information. The operation status calculation module is used to standardize the power supply configuration qualification rate, relay protection correct operation rate, annual average power outage time and voltage qualification rate of all users with the highest importance level, and perform weighted calculations to obtain the equipment operation status safety value of all users with the highest importance level. The operation status assessment module is used to compare the device operation status safety value with a preset status safety threshold. If the device operation status safety value is greater than the preset status safety threshold, the device on the user side with the highest importance level is determined to be in a reliable state. If the device operation status safety value is not greater than the preset status safety threshold, the device on the user side with the highest importance level is determined to be in a risky state.

7. The risk assessment system for the safety status of power grid equipment according to claim 6, characterized in that, The weighted undirected graph construction module specifically includes: The undirected graph construction module is used to construct an undirected graph based on the topological connection structure between all equipment nodes and the user side in the power distribution network. The weight module is used to construct a weighted undirected graph by using the electrical distance between all device nodes as the weight of the edges of the undirected graph.

8. The risk assessment system for the safety status of power grid equipment according to claim 6, characterized in that, Also includes: The segmentation module is used to divide the power supply path into multiple segments according to the segmentation switch, and obtain the maximum current value and rated current value corresponding to each segment. The load rate filtering module is used to calculate the current ratio between the maximum current value and the rated current value of each segment as the load rate of the corresponding segment, and to filter out the minimum load rate among all segments as the load rate threshold of the power supply path.

9. The risk assessment system for the safety status of power grid equipment according to claim 6, characterized in that, The topology analysis module is specifically used to perform topology analysis from the topology starting point upwards in the weighted undirected graph, based on the breadth-first search algorithm, with the user side with the highest importance level as the topology starting point and the power supply corresponding to the user side with the highest importance level as the topology ending point, to determine the nodes associated with the power supply of the topology starting point until the topology ending point, and obtain the power supply path. The power supply path includes the power supply, line, sectionalizing switch and relay protection equipment.

10. The risk assessment system for the safety status of power grid equipment according to claim 6, characterized in that, The voltage evaluation module specifically includes: The power outage time calculation module is used to calculate the average power outage time within the year based on the ratio of the power outage time of the user with the highest importance level to the total operating time within the year. The voltage acquisition module is used to acquire voltage data from the user side with the highest importance level at a preset frequency. The conversion module is used to perform a fast Fourier transform on the voltage data to obtain frequency domain voltage information; The voltage failure determination module is used to determine the number of voltage loss times, overvoltage times, and voltage imbalance times within a preset time period based on the frequency domain voltage information. The voltage failure calculation module is used to obtain the total number of voltage failures by statistically analyzing the number of voltage loss, the number of overvoltage, and the number of voltage imbalances, and to calculate the proportion of the total number of voltage failures in all sample points within the frequency domain voltage information. The voltage pass rate calculation module is used to calculate the average percentage of the total number of voltage failures on all user sides with the highest importance level, and thus obtain the voltage pass rate.

Images