Method and system for calculating equivalent load moment of medium voltage distribution network section based on failure probability

Abstract

The application discloses a kind of based on fault probability's medium voltage distribution network segmentation equivalent load moment calculation method and system, method includes: collection distribution network basic data;Determine target outage household number;Based on line fault probability and automation configuration mode, calculate the actual outage household number in the process of protection action, load transfer and fault repair;With actual outage household number does not exceed target value as constraint, in combination with regional load, line length and historical failure rate, calculate equivalent load moment;Finally, based on the index identification weak link of power grid.The equivalent load moment index of the application, electrical load and fault risk depth are fused, realize the measurement leap of from static stress to dynamic risk, can accurately quantified identification distribution network in high load-high risk bottleneck section, provide scientific basis for distribution network planning reconstruction and operation optimization, effectively improve the accuracy of power supply reliability evaluation, adapt to the development demand of new type power system.

Description

Technical Field

[0001] This invention belongs to the field of power system distribution network planning and operation technology, and particularly relates to a method and system for calculating the segmented equivalent load moment of a medium-voltage distribution network based on fault probability. Background Technology

[0002] With the deepening of the construction of new power systems, the penetration rate of distributed renewable energy in distribution networks is constantly increasing, and load distribution exhibits high spatiotemporal imbalance and uncertainty, posing unprecedented challenges to power supply reliability. Traditional distribution network planning methods mainly use power supply distance as the standard for judging the rationality of the network structure. This method is effective to a certain extent in grids with simple structures and uniform load distribution. However, in today's complex distribution network environment, considering only distance while ignoring factors such as line fault probability, load dynamic characteristics, and automation level, its limitations are becoming increasingly apparent, making it difficult to accurately identify the true weak links in the grid.

[0003] Load moment (the product of load and distance) is a classic indicator in distribution network planning, traditionally widely used for quickly assessing line voltage quality, determining economical power supply radius, and making preliminary comparisons of grid structures. However, the traditional load moment is a static indicator that only reflects the electrical stress of the power grid under normal operating conditions and cannot quantify the dynamic impact of fault risk on power supply reliability. For two lines with the same load moment, if one has a higher probability of failure due to environmental factors, equipment aging, etc., its actual operational reliability risk is obviously higher, but the traditional load moment indicator cannot reflect this difference.

[0004] Therefore, there is an urgent need in this field for a new indicator and calculation method that can integrate electrical load and fault risk, so as to achieve a more scientific and accurate evaluation of the distribution network planning and provide data support for differentiated planning, precise investment and operation optimization. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a method and system for calculating the segmented equivalent load moment of a medium-voltage distribution network based on fault probability. This method aims to dynamically weight the traditional load moment by introducing fault probability, defining and calculating the new index of "equivalent load moment," thereby achieving a comprehensive measurement of the "static pressure" and "dynamic risk" of the distribution network and accurately identifying weak links in the power grid.

[0006] In a first aspect, the present invention provides a method for calculating the segmented equivalent load moment of a medium-voltage distribution network based on fault probability, comprising:

[0007] Obtain basic data of medium-voltage distribution network in a specified area. The basic data of medium-voltage distribution network includes network structure, total load in the area, total line length, historical line failure rate in the area, distribution automation configuration mode, protection action time limit, load transfer time and fault repair time.

[0008] Based on the aforementioned medium-voltage distribution network basic data and power supply reliability requirements, determine the target number of households affected by a line outage;

[0009] Based on the line fault probability and according to the power distribution automation configuration mode, the number of households experiencing power outages during protection actions, load transfer, and fault repair is calculated respectively, and the actual number of households experiencing power outages in the specified area is obtained by summarizing.

[0010] With the constraint that the actual number of households during a power outage does not exceed the target number of households during a power outage, and in combination with the total load of the area, the total length of the lines, and the historical fault rate of the lines in the area, the equivalent load moment of the designated area is calculated.

[0011] Secondly, the present invention provides a segmented equivalent load moment calculation system for medium-voltage distribution networks based on fault probability, comprising:

[0012] The acquisition module is configured to acquire basic data of medium-voltage distribution network in a specified area. The basic data of medium-voltage distribution network includes network structure, total load of the area, total line length, historical failure rate of lines in the area, distribution automation configuration mode, protection action time limit, load transfer time and fault repair time.

[0013] The determination module is configured to determine the number of households at the time of the target power outage based on the medium-voltage distribution network basic data and power supply reliability requirements.

[0014] The first calculation module is configured to calculate the number of households experiencing power outages during protection actions, load transfer, and fault repair processes based on the line fault probability and according to the power distribution automation configuration mode, and summarize the actual number of households experiencing power outages in the specified area.

[0015] The second calculation module is configured to calculate the equivalent load moment of the specified area by taking the constraint that the number of households during the actual power outage does not exceed the target number of households during the power outage, and combining the total load of the area, the total length of the line, and the historical failure rate of the line in the area.

[0016] Thirdly, an electronic device is provided, comprising: at least one processor, and a memory communicatively connected to the at least one processor, wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the steps of the method for calculating the segmented equivalent load moment of a medium-voltage distribution network based on fault probability according to any embodiment of the present invention.

[0017] Fourthly, the present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein when the program instructions are executed by a processor, the processor performs the steps of the method for calculating the segmented equivalent load moment of a medium-voltage distribution network based on fault probability according to any embodiment of the present invention.

[0018] This application presents a method and system for calculating the segmented equivalent load moment of a medium-voltage distribution network based on fault probability. It defines a novel indicator, "equivalent load moment," achieving a leap from traditional static load moment to dynamic risk load moment measurement. By deeply integrating multiple factors such as electrical load intensity, line topology, fault probability, and distribution automation level, a scientifically rigorous calculation model is constructed. This equivalent load moment can accurately and quantitatively identify "high-load-high-risk" bottleneck sections in the distribution network, providing a clear priority decision basis for power grid planning, transformation, and operation optimization, effectively avoiding investment waste or inadequacy. Furthermore, the method features a closed-loop logic and clear steps, fully considering actual operating scenarios such as protection actions, load transfer, and fault repair. The calculation results closely match engineering realities, not only improving the accuracy of power supply reliability assessment but also adapting to the development needs of new power systems with high proportions of renewable energy integration. This provides crucial technical support for building a safe, efficient, and intelligent modern distribution network. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 A flowchart of a method for calculating the segmented equivalent load moment of a medium-voltage distribution network based on fault probability, provided in an embodiment of the present invention;

[0021] Figure 2 A structural block diagram of a segmented equivalent load moment calculation system for medium-voltage distribution networks based on fault probability, provided in an embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, 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.

[0024] Please see Figure 1 The diagram shows a flowchart of a method for calculating the segmented equivalent load moment of a medium-voltage distribution network based on fault probability, as proposed in this application.

[0025] like Figure 1 As shown, the method for calculating the segmented equivalent load moment of a medium-voltage distribution network based on fault probability specifically includes the following steps:

[0026] Step S101: Obtain basic data of medium-voltage distribution network in a specified area. The basic data of medium-voltage distribution network includes network structure, total load in the area, total line length, historical line failure rate in the area, distribution automation configuration mode, protection action time limit, load transfer time and fault repair time.

[0027] Step S102: Determine the target number of households when the line is shut down, based on the medium-voltage distribution network basic data and power supply reliability requirements.

[0028] In this step, based on the distribution network planning guidelines, the number of line segments and the maximum number of allowed users per segment are determined, and the maximum number of users connected to the line is calculated, expressed as:

[0029] ,

[0030] In the formula, This represents the maximum number of users that can access the line. Number of segments for the line The maximum number of users allowed in a single segment;

[0031] The target number of households to be affected by a power outage is calculated based on the maximum number of connected users on the line, using the following expression:

[0032] ,

[0033] In the formula, The target number of households during a power outage. The average power outage time requirement for a specified area.

[0034] Step S103: Based on the line fault probability and according to the power distribution automation configuration mode, calculate the number of households experiencing power outages during protection actions, load transfer, and fault repair, and summarize the actual number of households experiencing power outages in the specified area.

[0035] In this step, the line failure probability b is independently determined based on the historical failure rate of the regional lines and the total length of the lines;

[0036] The coefficient k is determined according to the power distribution automation configuration mode, wherein k=1 is taken for the centralized automation mode with master station remote control function, and k=0 is taken otherwise.

[0037] The expression for calculating the number of households affected by a power outage due to a protection device action is:

[0038] ;

[0039] In the formula, To determine the number of households affected by a power outage caused by a protective action, This represents the maximum number of users that can access the line. Configure operating time limits for line protection;

[0040] The expression for calculating the number of households affected by power outages during load transfer is as follows:

[0041] ,

[0042] In the formula, This refers to the number of households experiencing power outages during the load transfer process. The maximum number of users allowed in a single segment. The time required for line transfer;

[0043] The expression for calculating the number of households affected by power outages during fault repair is as follows:

[0044]

[0045] In the formula, This represents the number of households experiencing power outages during fault repair. The time required to restore power to the faulty section of the line;

[0046] The total number of households affected by actual power outages is calculated using the following expression:

[0047] .

[0048] Step S104: Taking the constraint that the actual number of households during a power outage does not exceed the target number of households during a power outage, and combining the total load of the area, the total length of the line, and the historical fault rate of the line in the area, calculate the equivalent load moment of the designated area.

[0049] In this step, the expression for calculating the equivalent load moment of the specified area is:

[0050] ,

[0051] In the formula, The equivalent load moment for a specified area, For regional load, The target number of households during a power outage. This represents the total length of the regional lines. For regional line failure rate, Configure operating time limits for line protection. The time required for line transfer. The time required to restore power to the faulty section of the line.

[0052] In summary, the method presented in this application defines a novel indicator, "equivalent load moment," achieving a leap from traditional static load moment measurement to dynamic risk load moment. By deeply integrating multiple factors such as electrical load intensity, line topology and fault probability, and distribution automation level, a scientifically rigorous calculation model is constructed. This equivalent load moment can accurately and quantitatively identify "high load-high risk" bottleneck sections in the distribution network, providing a clear priority decision basis for power grid planning, transformation, and operation optimization, effectively avoiding investment waste or inadequacy. Furthermore, the method features a closed-loop logic and clear steps, fully considering actual operating scenarios such as protection actions, load transfer, and fault repair. The calculation results closely align with engineering realities, not only improving the accuracy of power supply reliability assessment but also adapting to the development needs of new power systems with high proportions of renewable energy integration, providing crucial technical support for building a safe, efficient, and intelligent modern distribution network.

[0053] Please see Figure 2 The diagram shows a structural block diagram of a segmented equivalent load moment calculation system for a medium-voltage distribution network based on fault probability, as proposed in this application.

[0054] like Figure 2 As shown, the medium-voltage distribution network segmented equivalent load moment calculation system 200 includes an acquisition module 210, a determination module 220, a first calculation module 230, and a second calculation module 240.

[0055] The acquisition module 210 is configured to acquire basic data of the medium-voltage distribution network in a specified area. The basic data includes the network structure, total load of the area, total line length, historical line failure rate of the area, distribution automation configuration mode, protection action time limit, load transfer time, and fault repair time. The determination module 220 is configured to determine the target number of households affected by line outages based on the basic data of the medium-voltage distribution network and power supply reliability requirements. The first calculation module 230 is configured to calculate the number of households affected by outages during protection actions, load transfers, and fault repairs based on the line fault probability and the distribution automation configuration mode, and summarize the results to obtain the actual number of households affected by outages in the specified area. The second calculation module 240 is configured to calculate the equivalent load moment of the specified area, taking the constraint that the actual number of households affected by outages does not exceed the target number of households affected by outages, and combining the total load of the area, the total line length, and the historical line failure rate of the area.

[0056] It should be understood that Figure 2 The modules and references described in the document Figure 1 The steps described in the text correspond to those in the method described above. Therefore, the operations, features, and corresponding technical effects described above also apply to the method described in the text. Figure 2 The various modules in the document will not be described in detail here.

[0057] In other embodiments, the present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein when the program instructions are executed by a processor, the processor performs the method for calculating the segmented equivalent load moment of a medium-voltage distribution network based on fault probability in any of the above method embodiments.

[0058] In one embodiment, the computer-readable storage medium of the present invention stores computer-executable instructions, which are configured as follows:

[0059] Obtain basic data of medium-voltage distribution network in a specified area. The basic data of medium-voltage distribution network includes network structure, total load in the area, total line length, historical line failure rate in the area, distribution automation configuration mode, protection action time limit, load transfer time and fault repair time.

[0060] Based on the aforementioned medium-voltage distribution network basic data and power supply reliability requirements, determine the target number of households affected by a line outage;

[0061] Based on the line fault probability and according to the power distribution automation configuration mode, the number of households experiencing power outages during protection actions, load transfer, and fault repair is calculated respectively, and the actual number of households experiencing power outages in the specified area is obtained by summarizing.

[0062] With the constraint that the actual number of households during a power outage does not exceed the target number of households during a power outage, and in combination with the total load of the area, the total length of the lines, and the historical fault rate of the lines in the area, the equivalent load moment of the designated area is calculated.

[0063] Computer-readable storage media may include a stored program area and a stored data area, wherein the stored program area may store an operating system and an application program required for at least one function; the stored data area may store data created based on the use of a fault probability-based medium-voltage distribution network segmented equivalent load moment calculation system, etc. Furthermore, the computer-readable storage medium may include high-speed random access memory, and may also include memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state storage device. In some embodiments, the computer-readable storage medium may optionally include memory remotely located relative to a processor, which can be connected via a network to the fault probability-based medium-voltage distribution network segmented equivalent load moment calculation system. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0064] Figure 3 This is a schematic diagram of the structure of the electronic device provided in the embodiment of the present invention, such as... Figure 3 As shown, the device includes a processor 310 and a memory 320. The electronic device may also include an input device 330 and an output device 340. The processor 310, memory 320, input device 330, and output device 340 can be connected via a bus or other means. Figure 3 Taking a bus connection as an example, the memory 320 is the computer-readable storage medium described above. The processor 310 executes various server functions and data processing by running non-volatile software programs, instructions, and modules stored in the memory 320, thereby implementing the fault probability-based medium-voltage distribution network segmented equivalent load moment calculation method described in the above embodiment. The input device 330 can receive input digital or character information and generate key signal inputs related to user settings and function control of the fault probability-based medium-voltage distribution network segmented equivalent load moment calculation system. The output device 340 may include a display screen or other display device.

[0065] The aforementioned electronic device can execute the method provided in the embodiments of the present invention, and has the corresponding functional modules and beneficial effects for executing the method. Technical details not described in detail in this embodiment can be found in the method provided in the embodiments of the present invention.

[0066] In one implementation, the above-described electronic device is applied in a fault probability-based segmented equivalent load moment calculation system for medium-voltage distribution networks, serving as a client, and includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, which, when executed by the at least one processor, enable the at least one processor to:

[0067] Obtain basic data of medium-voltage distribution network in a specified area. The basic data of medium-voltage distribution network includes network structure, total load in the area, total line length, historical line failure rate in the area, distribution automation configuration mode, protection action time limit, load transfer time and fault repair time.

[0068] Based on the aforementioned medium-voltage distribution network basic data and power supply reliability requirements, determine the target number of households affected by a line outage;

[0069] Based on the line fault probability and according to the power distribution automation configuration mode, the number of households experiencing power outages during protection actions, load transfer, and fault repair is calculated respectively, and the actual number of households experiencing power outages in the specified area is obtained by summarizing.

[0070] With the constraint that the actual number of households during a power outage does not exceed the target number of households during a power outage, and in combination with the total load of the area, the total length of the lines, and the historical fault rate of the lines in the area, the equivalent load moment of the designated area is calculated.

[0071] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods of various embodiments or some parts of embodiments.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; 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; and these 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 method for calculating the segmented equivalent load moment of a medium-voltage distribution network based on fault probability, characterized in that, include: Obtain basic data of medium-voltage distribution network in a specified area. The basic data of medium-voltage distribution network includes network structure, total load in the area, total line length, historical line failure rate in the area, distribution automation configuration mode, protection action time limit, load transfer time and fault repair time. Based on the aforementioned medium-voltage distribution network basic data and power supply reliability requirements, determine the target number of households affected by a line outage; Based on the line fault probability and according to the distribution automation configuration mode, the number of households experiencing power outages during protection actions, load transfer, and fault repair is calculated separately, and the actual number of households experiencing power outages in the specified area is obtained by summing them up. The calculation of the number of households experiencing power outages during protection actions, load transfer, and fault repair, based on the line fault probability and according to the distribution automation configuration mode, and the summation of the actual number of households experiencing power outages in the specified area, includes: The line failure probability b is determined independently based on the historical failure rate and total length of the line in the region. The coefficient k is determined according to the power distribution automation configuration mode, wherein k=1 is taken for the centralized automation mode with master station remote control function, and k=0 is taken otherwise. The expression for calculating the number of households affected by a power outage due to a protection device action is: ； In the formula, To determine the number of households affected by a power outage caused by a protective action, This represents the maximum number of users that can access the line. Configure operating time limits for line protection; The expression for calculating the number of households affected by power outages during load transfer is as follows: ， In the formula, This refers to the number of households experiencing power outages during the load transfer process. The maximum number of users allowed in a single segment. The time required for line transfer; The expression for calculating the number of households affected by power outages during fault repair is as follows: In the formula, This represents the number of households experiencing power outages during fault repair. The time required to restore power to the faulty section of the line; The total number of households affected by actual power outages is calculated using the following expression: ； With the constraint that the actual number of households during a power outage does not exceed the target number of households during a power outage, and considering the total load of the area, the total length of the lines, and the historical fault rate of the lines in the area, the equivalent load moment of the specified area is calculated. The expression for calculating the equivalent load moment of the specified area is as follows: ， In the formula, The equivalent load moment for the specified area, For regional load, The target number of households during a power outage. This represents the total length of the regional lines. For regional line failure rate, Configure operating time limits for line protection. The time required for line transfer. The time required to restore power to the faulty section of the line.

2. The method for calculating the segmented equivalent load moment of a medium-voltage distribution network based on fault probability according to claim 1, characterized in that, The determination of the target number of households during a line outage, based on the medium-voltage distribution network basic data and power supply reliability requirements, includes: According to the distribution network planning guidelines, the number of line segments and the maximum number of allowed users per segment are determined, and the maximum number of users connected to the line is calculated using the following expression: ， In the formula, This represents the maximum number of users that can access the line. Number of segments for the line The maximum number of users allowed in a single segment; The target number of households to be affected by a power outage is calculated based on the maximum number of connected users on the line, using the following expression: ， In the formula, The target number of households during a power outage. The average power outage time requirement for a specified area.

3. A system for calculating the segmented equivalent load moment of a medium-voltage distribution network based on fault probability, characterized in that, include: The acquisition module is configured to acquire basic data of medium-voltage distribution network in a specified area. The basic data of medium-voltage distribution network includes network structure, total load of the area, total line length, historical failure rate of lines in the area, distribution automation configuration mode, protection action time limit, load transfer time and fault repair time. The determination module is configured to determine the number of households at the time of the target power outage based on the medium-voltage distribution network basic data and power supply reliability requirements. The first calculation module is configured to calculate the number of households experiencing power outages during protection actions, load transfer, and fault repair processes based on the line fault probability and according to the distribution automation configuration mode, and summarize the total number of households experiencing power outages in a specified area. The calculation of the number of households experiencing power outages during protection actions, load transfer, and fault repair processes based on the line fault probability and according to the distribution automation configuration mode, and the summation of the total number of households experiencing power outages in the specified area, includes: The line failure probability b is determined independently based on the historical failure rate and total length of the line in the region. The coefficient k is determined according to the power distribution automation configuration mode, wherein k=1 is taken for the centralized automation mode with master station remote control function, and k=0 is taken otherwise. The expression for calculating the number of households affected by a power outage due to a protection device action is: ； In the formula, To determine the number of households affected by a power outage caused by a protective action, This represents the maximum number of users that can access the line. Configure operating time limits for line protection; The expression for calculating the number of households affected by power outages during load transfer is as follows: ， In the formula, This refers to the number of households experiencing power outages during the load transfer process. The maximum number of users allowed in a single segment. The time required for line transfer; The expression for calculating the number of households affected by power outages during fault repair is as follows: In the formula, This represents the number of households experiencing power outages during fault repair. The time required to restore power to the faulty section of the line; The total number of households affected by actual power outages is calculated using the following expression: ； The second calculation module is configured to calculate the equivalent load moment of the specified area, based on the constraint that the actual number of households during a power outage does not exceed the target number of households during a power outage, and in conjunction with the total load of the area, the total length of the lines, and the historical fault rate of the lines in the area. The expression for calculating the equivalent load moment of the specified area is as follows: ， In the formula, The equivalent load moment for the specified area, For regional load, The target number of households during a power outage. This represents the total length of the regional lines. For regional line failure rate, Configure operating time limits for line protection. The time required for line transfer. The time required to restore power to the faulty section of the line.

4. An electronic device, characterized in that, include: At least one processor, and a memory communicatively connected to the at least one processor, wherein the memory stores instructions executable by the at least one processor to enable the at least one processor to perform the method according to any one of claims 1 to 2.

5. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the method described in any one of claims 1 to 2.

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