Digital twin-based power distribution network power supply reliability calculation method and system

Abstract

The present application provides a digital twin-based power distribution network power supply reliability calculation method and system. The method comprises: obtaining basic data and operation data of a power distribution line; constructing a digital twin power grid on the basis of the digital twin technology as well as the basic data and the operation data; obtaining scores in respect of power distribution network reliability indexes of the power distribution line on the basis of the digital twin power grid, wherein the power distribution network reliability indexes comprise an element reliability index, a load point reliability index, a system reliability index, a series system reliability index, and a parallel system reliability index; and on the basis of a weighted fusion result of the scores of the power distribution network reliability indexes, determining the power distribution network power supply reliability to be calculated. The present application solves the problem that current methods for analyzing the power distribution network power supply reliability relate to treating entire power distribution networks as research objects and implementing manual sorting, and thus are time-consuming and labor-intensive, are difficult to ensure the accuracy of calculation results, and fail to conduct statistical analysis for weak links in the network distribution networks.

Description

A method and system for calculating power supply reliability of distribution network based on digital twin Technical Field

[0001] The present application relates to the technical field of distribution network reliability analysis, and in particular to a distribution network power supply reliability calculation method and system based on digital twins. Background Art

[0002] The reliability of distribution network power supply is the most direct reflection of a power company's service quality. It's not only related to user trust in the company but also closely linked to the company's own economic interests and long-term development. As user demands for distribution network reliability continue to rise, power companies are placing increasing emphasis on optimizing distribution network architecture and improving power supply reliability.

[0003] Currently, research on distribution network reliability focuses on the planning and transformation of distribution networks from a global perspective. This approach uses the entire distribution network as the research object and utilizes various algorithms to develop a reasonable grid structure model and optimal operation mode. Addressing weak links in the distribution network structure typically involves strengthening data management. This requires manual review of data such as line segment connectivity, excessive overhead line direct capacity, overhead line direct switch station loops, and substation outgoing line direct supply loops.

[0004] However, manually analyzing the entire distribution network is time-consuming and labor-intensive, and the accuracy of the calculation results is difficult to guarantee. Furthermore, with economic development, the types and capacities of distribution network loads are constantly changing. It is unrealistic to modify the overall operation of the distribution network after each analysis of the entire network. Therefore, a method is urgently needed to conduct statistical analysis on the weak links in the distribution network, intuitively identify the weak links in the distribution network structure, and provide guarantees for optimizing the distribution network structure and improving power supply reliability.

[0005] Summary of the Invention

[0006] The embodiments of the present application provide a method and system for calculating the power supply reliability of a distribution network based on digital twins to solve the technical problem that the current power supply reliability analysis of the distribution network can only be carried out by manually combing the entire distribution network as a research object, which is time-consuming and labor-intensive, and it is difficult to ensure the accuracy of the calculation results, and it is impossible to perform statistical analysis on the weak links of the distribution network.

[0007] In a first aspect, the present application provides a method for calculating the power supply reliability of a distribution network based on digital twins, comprising:

[0008] Obtain basic data and operation data of distribution lines;

[0009] Building a digital twin power grid based on digital twin technology and the basic data and operation data;

[0010] Based on the digital twin power grid, obtain the scores of distribution line distribution network reliability indicators; the distribution network reliability indicators include component reliability indicators, load point reliability indicators, system reliability indicators, series system reliability indicators, and parallel system reliability indicators;

[0011] Based on the weighted fusion result of the distribution network reliability index scores, the power supply reliability of the distribution network to be calculated is determined.

[0012] In some embodiments, building a digital twin power grid based on digital twin technology and the basic data and operating data includes:

[0013] Based on basic data and operating data, daily collection data is obtained at a set period;

[0014] Calculate the index values ​​of different dimensions of the distribution network based on daily collected data and generate daily samples;

[0015] Generate multi-time scale sample sequences based on daily samples;

[0016] Inputting the multi-time scale sample sequence into the inverse cloud to generate fuzzy concepts;

[0017] Matching the fuzzy concepts with given labels, and generating images of distribution network substations and lines based on the closeness and proximity selection principle of fuzzy sets;

[0018] Based on the images of distribution network substations and lines, a digital twin power grid is constructed using digital twin technology.

[0019] In some embodiments, the method for calculating power supply reliability of a distribution network based on digital twins further includes:

[0020] Analyze substation equipment information, distribution line equipment information, grid topology and equipment coordinate information to generate a real-time distribution network operation diagram;

[0021] The power supply reliability calculation result of the distribution network is sent to the distribution network operation line diagram.

[0022] In some embodiments, the basic data includes: the name of the distribution line, the type of the distribution line, the unit to which the distribution line belongs, the substation to which the distribution line belongs, and parameter information, topology information and coordinate information of the transformers, disconnectors, circuit breakers, tie switches and transmission line equipment in the distribution line.

[0023] In some embodiments, the operating data includes: outgoing switch voltage, current, active power, reactive power, power factor, electrical quantity and phase sequence data.

[0024] In some embodiments, the component reliability indicators include: failure rates and repair rates of transformers, disconnectors, circuit breakers, tie switches, and transmission lines in the distribution network;

[0025] The load point reliability indicators include: average load point failure rate, average load point downtime and average load point failure repair time;

[0026] The system reliability indicators include: system average power outage frequency, system average power supply availability, user average power outage duration, system average power outage duration, and power shortage expectation;

[0027] The reliability index of the series system includes: equivalent failure rate, equivalent repair time, and equivalent annual downtime of the system composed of multiple components in series;

[0028] The reliability indexes of the parallel system include: equivalent failure rate, equivalent failure repair time, and average power outage time of the load point of the system composed of multiple components in parallel.

[0029] In some embodiments, the daily collected data includes: electricity data, data of each substation, and data of each line;

[0030] The multi-time-scale sample sequence includes: an annual sample sequence, a quarterly sample sequence, a monthly sample sequence, and a weekly sample sequence.

[0031] A second aspect of the present application provides a distribution network power supply reliability calculation system based on digital twins, which is applied to a distribution network power supply reliability calculation method based on digital twins as described in any one of the first aspects above, comprising: a physical layer, a data acquisition layer, a model layer, a function layer, and a presentation layer;

[0032] The physical layer includes: distribution transformer equipment, distribution line equipment, and distributed photovoltaic physical equipment;

[0033] The data acquisition layer is used to collect, transmit and store data from the physical layer;

[0034] The model layer is used to convert the reliability index into a model;

[0035] The functional layer is used to analyze, diagnose, and predict the data collected by the data collection layer, and adjust the lean management and optimization of physical entities; the physical entities include: distribution transformer equipment, distribution line equipment, and distributed photovoltaic physical equipment.

[0036] In some embodiments, the system further comprises:

[0037] The presentation layer includes: power grid GIS, substation topology map, and related information system user interface, which is used to display the power supply reliability results of the distribution network to users.

[0038] In some embodiments, the data acquisition layer includes:

[0039] A collection device, used for collecting data of the physical layer;

[0040] A transmission network, the transmission network being in communication with the acquisition device and being used to transmit physical layer data;

[0041] The data middle platform is in communication with the acquisition device and is used to store data at the physical layer.

[0042] An embodiment of the present application provides a method and system for calculating the power supply reliability of a distribution network based on digital twins, including: obtaining basic data and operating data of distribution lines; constructing a digital twin power grid based on digital twin technology and the basic data and operating data; obtaining scores of distribution line and distribution network reliability indicators based on the digital twin power grid; the distribution network reliability indicators include component reliability indicators, load point reliability indicators, system reliability indicators, series system reliability indicators, and parallel system reliability indicators; based on the weighted fusion results of the distribution network reliability index scores, determining the power supply reliability of the distribution network to be calculated, so as to realize the statistical analysis of the weak links of the distribution network through the digital twin technology, without the need to manually sort out the entire distribution network as a research object, thereby improving the calculation efficiency and the accuracy of the calculation results. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0044] FIG1 is a flow chart of a method for calculating power supply reliability of a distribution network based on digital twins in this application;

[0045] FIG2 is a schematic diagram of the structure of the distribution network power supply reliability calculation system based on digital twin in this application;

[0046] FIG3 is a schematic diagram of the structure of the data acquisition layer in this application.

[0047] Description of reference numerals:

[0048] 1-Physical layer; 2-Data acquisition layer; 21-Acquisition device; 22-Transmission network; 23-Data middle platform; 3-Model layer; 4-Functional layer; 5-Presentation layer. DETAILED DESCRIPTION

[0049] In order to enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of this application.

[0050] In some technologies, the reliability of distribution network power supply can only be analyzed by manually combing the entire distribution network as the research object, which is time-consuming and labor-intensive, and it is difficult to ensure the accuracy of the calculation results. It is also impossible to perform statistical analysis on the weak links of the distribution network. In order to solve this technical problem, this application provides a distribution network power supply reliability calculation method and system based on digital twins. The following describes the distribution network power supply reliability calculation method and system based on digital twins:

[0051] As shown in Figure 1, this application provides a method for calculating the power supply reliability of a distribution network based on digital twins, including:

[0052] Obtain basic data and operating data of the distribution line; the basic data includes: the name of the distribution line, the type of distribution line, the unit to which the distribution line belongs, the substation to which the distribution line belongs, and the parameter information, topology information and coordinate information of the transformer, disconnector, circuit breaker, tie switch and transmission line equipment in the distribution line; the operating data includes: the voltage, current, active power, reactive power, power factor, electricity and phase sequence data of the outgoing line switch.

[0053] Based on digital twin technology and the basic data and operating data, a digital twin power grid is constructed; the digital twin power grid constructed based on digital twin technology and the basic data and operating data includes: based on the basic data and operating data, daily collected data is obtained at a set period; the daily collected data includes: electricity data, data of each substation, and data of each line; the index values ​​of different dimensions of the distribution network are calculated according to the daily collected data to generate daily samples; based on the daily samples, a multi-time scale sample sequence is generated; the multi-time scale sample sequence includes: annual sample sequence, quarterly sample sequence, monthly sample sequence, and weekly sample sequence; the multi-time scale sample sequence is input into the reverse cloud to generate fuzzy concepts; the fuzzy concepts are matched with given labels, and based on the closeness and proximity selection principle of fuzzy sets, images of distribution network substations and lines are generated; based on the images of distribution network substations and lines, a digital twin power grid is constructed using digital twin technology.

[0054] Based on the digital twin grid, the distribution network reliability index scores of the distribution lines are obtained. The distribution network reliability index includes the component reliability index, the load point reliability index, the system reliability index, the series system reliability index, and the parallel system reliability index. The component reliability index includes the failure rate and repair rate of transformers, disconnectors, circuit breakers, tie switches, and transmission lines in the distribution network. The component failure rate is expressed as the number of times a component fails and fails within a statistical period, usually represented by λ.

[0055] The component repair rate is expressed as the time it takes to repair components that need to be evaluated, and records the actual time used for repair, mainly including the time for fault inspection, location, and correction;

[0056] The load point reliability index includes: average load point failure rate, average load point outage time and average load point fault repair time; its calculation method is: assuming that J is the set of components in the distribution system that cause load point outage failure; λ j is the average failure rate of each component between a load point and the power supply point in the distribution system; μ j is the average fault repair time of each component between a load point and the power supply point in the distribution system. The definition and calculation formula of the load power reliability index are as follows:

[0057] The load point average failure rate refers to the number of times the power supply to a load point is interrupted due to component failure in the system during a statistical period of a load point in the power distribution system. In general, it is expressed as λ i It is expressed in times / year. The calculation formula is as follows:

[0058] The average outage time of the load point refers to the time when the users in the system are out of power during the statistical period, usually expressed as U i Indicates, unit: hours / year; its calculation formula is as follows: U i =∑λ j r j ;

[0059] The load point mean fault repair time refers to the average value of the time from the start of a power outage to the restoration of normal power supply at a load point in the system, usually expressed in μ i Indicated in hours / year; the calculation formula is as follows:

[0060] The system reliability indicators include: system average power outage frequency, system average power supply availability, user average power outage duration, system average power outage duration, and power shortage expectation; the calculation method is: assuming U iis the annual average outage time of load point i in the distribution system; i is the user outage rate at load point i in the distribution system; N i is the number of users at load point i in the distribution system; L a(i) is the load level connected to the load point i in the distribution system; the definition and calculation formula of the system reliability index are as follows:

[0061] The system average power outage frequency refers to the average number of power outages that occur to each user in the power distribution system during a statistical period, in units of times / (user-year). The calculation formula is as follows:

[0062] The system average power outage duration refers to the duration of a power outage for each user in the power distribution system during the statistical period, in hours (user-year). The calculation formula is as follows:

[0063] The average power outage duration for users refers to the average duration of power outages for users who experienced power outages in the power distribution system during the statistical period, in hours (power outage users per year). The calculation formula is as follows:

[0064] The average power supply availability refers to the ratio of the total number of normal power supply hours obtained by users during the statistical period of the power distribution system to the total power supply hours required by users. The calculation formula is as follows:

[0065] The expected power shortage refers to the power shortage on the user side caused by the outage of components in the system during the entire statistical period, in megawatt-hours / year; its calculation formula is as follows: EENS=∑U i L a(i) .

[0066] The series system reliability index includes: the equivalent failure rate, equivalent repair time, and equivalent annual downtime of a system composed of multiple components in series; the series system reliability index includes the equivalent failure rate λ, equivalent repair time γ, and equivalent annual downtime U of a system composed of two or more components in series, and the calculation method is:

[0067] The equivalent failure rate λ is:

[0068] The equivalent repair time γ is:

[0069] The equivalent annual outage time U is:

[0070] The parallel system reliability index includes: the equivalent failure rate of the load point of the system composed of multiple components in parallel, the equivalent failure repair time, and the average power outage time. The parallel system reliability index includes the equivalent failure rate λ of the load point of the system composed of two or more components in parallel. P , equivalent fault repair time γ P , average power outage time U P , assuming that the failure rate of the components in the system is λ and the failure repair time is μ. The reliability index calculation formula of the two-component parallel system is as follows:

[0071] The equivalent failure rate λ P is: P =λ1λ2(μ1+μ2)(times / year);

[0072] The equivalent fault repair time γ P is: γ P =μ1μ2 / (μ1+μ2)(hours / time);

[0073] The average power outage time U P For: U P =λ P γ P (hours / year);

[0074] The reliability index calculation formula of the three-component parallel system is as follows:

[0075] The equivalent failure rate λ P is: P =λ1λ2λ3(μ1μ2+μ2μ3+μ3μ1)(times / year);

[0076] The equivalent fault repair time γ P is: γ P =μ1μ2μ3 / (μ1μ2+μ2μ3+μ3μ1)(hour / time);

[0077] The average power outage time U P For: U P =λ P γ P =λ1λ2λ3μ1μ2μ3(hours / year).

[0078] Based on the weighted fusion result of the distribution network reliability index scores, the power supply reliability of the distribution network to be calculated is determined.

[0079] The distribution network reliability index is, for example, evaluated by the equivalent failure rate λ = 100 times / year and the average fault repair time γ = 24 hours / time. Thus, if the equivalent failure rate of the distribution network is 100 times / year, the score of the index is 60 points, if the component failure rate is 0 times / year, the score of the index is 100 points, and if the failure rate is 1000 times / year, the score of the index is 0 points. If the equivalent failure rate of the distribution network in a certain sampling period is λ t =50 times / year, then the reliability index score of this distribution network is D λt = 80 points; if the fault repair time is set to 24 hours / time, the score of this indicator is 60 points; if the fault repair time is 1 hour / time, the score of this indicator is 100 points; if the fault repair time is 120 hours / time, the score of this indicator is 0 points; if the fault repair time of a distribution network with a cycle is γ t1 =48 hours / time, γ t2 =12 hours / time, then the scores of this distribution network on this reliability index are D γt1 =40 points and D γt2 = 80 points; the weighted fusion result of the reliability score of the distribution network is calculated by weighted average method of multiple reliability index scores, such as the reliability score of the sampling period is:

[0080] As shown in Figure 1, the method further includes: parsing substation equipment information, distribution line equipment information, grid topology, and equipment coordinate information to generate a real-time distribution network operation diagram; and sending the distribution network power supply reliability calculation results to the distribution network operation diagram. By parsing the substation equipment information, distribution line equipment information, grid topology, and equipment coordinate information, a real-time distribution network operation diagram is automatically generated, and the distribution network reliability calculation results obtained by the distribution network reliability index calculation module are visualized in the distribution network operation diagram.

[0081] The beneficial effects of a distribution network power supply reliability calculation method and system based on digital twins provided in the present application are: the present application can obtain distribution network equipment parameter information, grid topology information and equipment coordinate information in real time, obtain distribution network equipment operation data in real time, obtain distribution network equipment fault information in real time and update equipment reliability indicators, and perform power supply reliability calculation and evaluation in real time based on distribution network reliability indicator calculation; based on the current equipment parameters, grid topology and equipment coordinate information of the distribution network, generate the actual operation diagram of the distribution network according to the actual proportion, combine the actual operation data of the distribution network with the equipment reliability index data, and perform power supply reliability calculation and evaluation, with high accuracy of the calculation results.

[0082] As can be seen from Figure 2, the second aspect of the present application provides a distribution network power supply reliability calculation system based on digital twins, which is applied to a distribution network power supply reliability calculation method based on digital twins described in any of the above embodiments, including: physical layer 1, data acquisition layer 2, model layer 3, function layer 4, presentation layer 5; the physical layer 1 includes: distribution transformer equipment, distribution line equipment, distributed photovoltaic physical equipment; the data acquisition layer 2 is used to collect, transmit and store data of the physical layer 1; as can be seen from Figure 3, the data acquisition layer 2 includes: an acquisition device 21 for collecting data of the physical layer 1; a transmission network 22, the transmission network 22 is communicated with the acquisition device 21 for transmitting data of the physical layer 1; a data middle platform 23, the data middle platform 23 is communicated with the acquisition device 21 for storing physical The data of the physical layer 1; the model layer 3 is used to convert the reliability index into a model; the model layer 3 includes various calculation and analysis models, which are used for evaluation and analysis by converting the reliability index into a model; the functional layer 4 is used to analyze, diagnose and predict the data collected by the data acquisition layer 2, and adjust the lean management and optimization of the physical entity; the functional layer 4 includes a calculation and analysis module to realize the analysis, diagnosis and prediction of the data collected by the data acquisition layer, and can realize the lean management and optimization adjustment of the physical entity; the physical entity, that is, the physical layer entity equipment, includes: distribution transformer equipment, distribution line equipment, distributed photovoltaic physical equipment; the system also includes: presentation layer 5, the presentation layer 5 includes: power grid GIS, substation topology map, related information system user interface, which is used to display the distribution network power supply reliability results to the user. The effects of each part of the above system when executing the above method can be found in the above method embodiment, which will not be repeated here.

[0083] The above specific implementation methods further explain in detail the purpose, technical solutions and beneficial effects of the embodiments of the present application. It should be understood that the above are only specific implementation methods of the embodiments of the present application and are not intended to limit the scope of protection of the embodiments of the present application. Any modifications, equivalent replacements, improvements, etc. made on the basis of the technical solutions of the embodiments of the present application should be included in the scope of protection of the embodiments of the present application.

Claims

1. A method for calculating power supply reliability of distribution network based on digital twin, characterized in that: include: Obtain basic data and operation data of distribution lines; Building a digital twin power grid based on the digital twin technology and the basic data and operation data; Based on the digital twin power grid, the scores of the distribution network reliability indicators of the distribution lines are obtained; the distribution network reliability indicators include component reliability indicators, load point reliability indicators, system reliability indicators, series system reliability indicators, and parallel system reliability indicators; Based on the weighted fusion result of the distribution network reliability index scores, the power supply reliability of the distribution network to be calculated is determined.

2. According to a method for calculating power supply reliability of a distribution network based on digital twins according to claim 1, it is characterized in that: The construction of a digital twin power grid based on the digital twin technology and the basic data and operation data includes: Based on basic data and operation data, daily collection data is obtained at a set period; Calculate the index values ​​of different dimensions of the distribution network based on the daily collected data and generate daily samples; Generate multi-time scale sample sequences based on daily samples; Inputting the multi-time scale sample sequence into the reverse cloud to generate fuzzy concepts; Matching the fuzzy concept with a given label, and generating images of distribution network substations and lines based on the closeness and proximity selection principle of the fuzzy set; Based on the images of distribution network substations and lines, a digital twin power grid is constructed using digital twin technology.

3. According to a method for calculating power supply reliability of a distribution network based on digital twinning according to claim 1, it is characterized in that: The method further comprises: Analyze substation equipment information, distribution line equipment information, grid topology and equipment coordinate information to generate a real-time distribution network operation line diagram; The power supply reliability calculation result of the distribution network is sent to the distribution network operation line diagram.

4. The method for calculating power supply reliability of a distribution network based on digital twin according to claim 1, characterized in that: The basic data include: the name of the distribution line, the type of distribution line, the unit to which the distribution line belongs, the substation to which the distribution line belongs, and parameter information, topology information and coordinate information of the transformer, disconnector, circuit breaker, tie switch and transmission line equipment in the distribution line.

5. The method for calculating power supply reliability of a distribution network based on digital twin according to claim 1, characterized in that: The operating data include: outgoing line switch voltage, current, active power, reactive power, power factor, electrical quantity and phase sequence data.

6. The method for calculating power supply reliability of a distribution network based on digital twin according to claim 1, characterized in that: The component reliability indicators include: failure rate and repair rate of transformers, disconnectors, circuit breakers, tie switches and transmission lines in the distribution network; The load point reliability index includes: average load point failure rate, average load point downtime and average load point failure repair time; The system reliability indicators include: average power outage frequency of the system, average power supply availability of the system, average power outage duration of users, average power outage duration of the system, and power shortage expectation; The reliability index of the series system includes: equivalent failure rate, equivalent repair time, and equivalent annual downtime of the system composed of multiple components in series; The reliability indexes of the parallel system include: equivalent failure rate, equivalent failure repair time and average power outage time of the load point of the system composed of multiple components in parallel.

7. The method for calculating power supply reliability of a distribution network based on digital twin according to claim 2 is characterized in that: The daily collected data includes: electricity data, data of each substation, and data of each line; The multi-time scale sample sequence includes: annual sample sequence, quarterly sample sequence, monthly sample sequence, and weekly sample sequence.

8. A distribution network power supply reliability calculation system based on digital twin, applied to a distribution network power supply reliability calculation method based on digital twin as described in any one of claims 1 to 7, characterized in that: include: Physical layer (1), data collection layer (2), model layer (3), functional layer (4), presentation layer (5); The physical layer (1) includes: distribution transformer equipment, distribution line equipment, and distributed photovoltaic physical equipment; The data acquisition layer (2) is used to collect, transmit and store data from the physical layer (1); The model layer (3) is used to convert the reliability index into a model; The functional layer (4) is used to analyze, diagnose and predict the data collected by the data collection layer (2) to adjust the lean management and optimization of physical entities; the physical entities include: distribution transformer equipment, distribution line equipment, and distributed photovoltaic physical equipment.

9. A distribution network power supply reliability calculation system based on digital twin according to claim 8, characterized in that: The system further comprises: The presentation layer (5) includes: a power grid GIS, a substation topology map, and a related information system user interface, and is used to present the power supply reliability results of the distribution network to users.

10. A distribution network power supply reliability calculation system based on digital twin according to claim 8, characterized in that: The data collection layer (2) comprises: A collection device (21) for collecting data of the physical layer (1); A transmission network (22), the transmission network (22) being communicatively connected to the collection device (21) and being used for transmitting data of the physical layer (1); A data middle platform (23), the data middle platform (23) is communicatively connected to the acquisition device (21) and is used to store data of the physical layer (1).

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