A method and device for calculating power supply reliability considering low voltage transfer

Abstract

The present invention relates to a method and device for calculating power supply reliability considering low-voltage transfer, the method comprising the following steps: obtaining real-time low-voltage area basic data and operation data, obtaining fault information of each low-voltage area equipment; calculating power supply reliability parameters according to equipment type; performing topological analysis based on actual operation grid topology data and ledger data of low-voltage area equipment, finding low-voltage contact switches and their positions in low-voltage areas; determining feasible load transfer paths in combination with ledger data and operation data; and calculating power supply reliability based on the positions of feasible load transfer paths. Compared with the prior art, the present invention has the advantages of being able to accurately reflect the power supply reliability rate.

Description

Technical Field

[0001] The present invention relates to the field of power supply reliability evaluation and analysis of power grids, and in particular to a power supply reliability calculation method and device taking low-voltage transfer into consideration. Background Art

[0002] The power grid is an important part of the power system. Its power supply reliability has an important impact on the stability of the power industry development, and is also directly related to the reliability, safety, and stability of users' electricity use. With the continuous increase in social electricity consumption, the load on the power grid is getting bigger and bigger, which greatly increases the probability of overload operation of the power grid, resulting in an increase in regional power outages caused by power grid failures, affecting the reliability of power grid power supply. Therefore, the effectiveness and accuracy of power grid power supply reliability calculation and evaluation have become issues of concern to power companies.

[0003] Low-voltage substations are an important part of the power grid and are also the place where power supply reliability is directly reflected. As power companies pay more attention to power supply reliability, more and more low-voltage connections are being used to ensure power supply to users. Currently, the power supply reliability assessment process is mostly from the substation outlet to the distribution transformer at the end of the distribution line. The influencing factors considered are not comprehensive and cannot accurately reflect the power supply reliability rate of the actual operating power grid. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and to provide a power supply reliability calculation method and device that can accurately reflect the power supply reliability rate and take low-voltage transfer into consideration.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] A method for calculating power supply reliability considering low-voltage power transfer includes the following steps:

[0007] Obtain real-time low-voltage area basic data and operation data, the basic data including actual operation grid topology data and ledger data of low-voltage area equipment;

[0008] Obtain fault information of each low-voltage area equipment;

[0009] Based on the ledger data and fault information, power supply reliability parameters are calculated according to equipment type;

[0010] Perform topological analysis based on the actual operation grid topology data and ledger data of the low-voltage area equipment to find the low-voltage contact switch and its location in the low-voltage area;

[0011] Based on the position of the low-voltage contact switch in the low-voltage area, a feasible load transfer path is determined in combination with the account data and operation data;

[0012] Based on the location of the feasible load transfer path, the power supply reliability is calculated. Specifically: if the feasible load transfer path is located at the head end of the substation, the low-voltage transfer equipment is equivalent to the opposite distribution transformer, and the reliability parameters use the parameters of the opposite distribution transformer to calculate the power supply reliability; if the low-voltage transfer path is located at the end of the substation, the connecting switch is equivalent to the low-voltage substation terminal equipment, and the reliability parameters use the parameters of the opposite low-voltage substation terminal equipment to calculate the power supply reliability.

[0013] Furthermore, the low-voltage substation equipment includes distribution transformers, pole-mounted transformers, overhead lines, cable segments, circuit breakers, disconnectors, load switches and low-voltage users.

[0014] Furthermore, the operating data includes active power, reactive power and power factor at the head end of the substation area and power consumption data of users at the end of the substation area.

[0015] Furthermore, the fault information includes the name of the faulty device, the ID of the faulty device, the time of occurrence of the fault, the duration of the fault, and the number of users affected by the fault.

[0016] Furthermore, the power supply reliability parameters include equipment failure rate and equipment failure repair time.

[0017] Further, the step of finding the low-voltage contact switch is as follows:

[0018] Analyze switch information based on actual grid topology data, decompose each switch into a common switch, analyze the normally open switch as a suspected tie switch based on whether the switch is normally open, and analyze the open switch as a suspected tie switch based on the actual open and closed state of the switch;

[0019] The suspected connecting switch is analyzed. If the same switch belongs to different low-voltage areas, then the switch is a connecting switch, otherwise it is an ordinary switch.

[0020] Furthermore, the feasible load transfer path meets the following conditions: during the load transfer process, the line load of the tie switch is not too high or the user's electricity demand cannot be met.

[0021] Furthermore, when calculating the power supply reliability, the low-voltage substation equipment parameters, grid topology and equipment coordinate information are integrated to construct the actual operation diagram of the low-voltage substation. The final power supply reliability is calculated by combining the real-time operation data of the low-voltage substation and the power supply reliability parameters of the low-voltage substation equipment.

[0022] Furthermore, the method further comprises:

[0023] The result of the power supply reliability calculation is displayed.

[0024] The present invention also provides an electronic device, comprising:

[0025] one or more processors;

[0026] Memory; and

[0027] One or more programs stored in the memory, the one or more programs including instructions for executing the power supply reliability calculation method as described above.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. Based on virtual modeling technology, the present invention utilizes the grid topology data, equipment inventory data and real-time operation data of the actual operation of the low-voltage substation in the power grid to construct a low-voltage substation power supply reliability assessment model, and performs power supply reliability calculation considering low-voltage transfer, which can more effectively reflect the power supply reliability rate of the actual operating power grid.

[0030] 2. The present invention considers the feasibility of the low-voltage transfer path and its different locations, performs low-voltage connection equivalence, and can obtain more reliable power supply reliability calculation results. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the process of the present invention. DETAILED DESCRIPTION

[0032] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0033] like Figure 1 As shown, this embodiment provides a method for calculating power supply reliability considering low-voltage transfer, including the following steps:

[0034] S101, access low voltage area data.

[0035] The basic data and operation data of low-voltage substation equipment are accessed in real time through the middle platform interface. Among them, low-voltage substation equipment includes distribution transformers, pole-mounted transformers, overhead lines, cable segments, circuit breakers, disconnectors, load switches, low-voltage users, etc. The basic data includes the actual operation of the access equipment network topology data and equipment ledger data, and the operation data includes the active power, reactive power, power factor, etc. at the head end of the substation and the power data of the end users in the substation.

[0036] S102. Access device failure data.

[0037] Access the low-voltage equipment fault data through the distribution network terminal fault system interface. The fault data includes the fault equipment name, fault equipment ID, fault occurrence time, fault duration, number of users affected by the fault, etc., which are divided into real-time fault information and historical fault information.

[0038] S103, calculating equipment reliability parameters.

[0039] Combining the low-voltage substation equipment inventory data with equipment failure information, the power supply reliability parameters are calculated according to the equipment type, and the equipment failure rate and equipment failure repair time of each type of equipment are calculated.

[0040] The specific calculation formula is: Overhead line failure rate = total number of overhead line failures * 100km / total length of overhead lines, in units of (times / 100km * year); Cable section failure rate = total number of cable section failures * 100km / total length of cable section, in units of (times / 100km * year); Transformer failure rate = total number of transformer failures / total number of transformers, in units of (times / year); Circuit breaker failure rate = total number of circuit breaker failures / total number of circuit breakers, in units of (times / year); Load switch failure rate = total number of load switch failures / total number of load switches, in units of (times / year); Disconnector failure rate = total number of disconnector failures / total number of disconnectors, in units of (times / year); Equipment failure repair time Fault repair time is the average annual repair time for each type of equipment.

[0041] S104. Identify the low-voltage area interconnecting switches through topological analysis.

[0042] Relying on the access equipment grid topology data and equipment ledger data, topology analysis is performed to identify the interconnection switch by judging whether the same switch belongs to different areas, and to determine whether the low-voltage area switch is an interconnection switch or an ordinary switch. Specifically:

[0043] Analyze the switch information and divide the switches into ordinary switches (circuit breakers, load switches, etc.), T-type switches, V-type switches and three-position load switches according to the different switch types. Among them, T-type switches, V-type switches and three-position load switches are separated according to the components of the switches through data analysis, and the separated components are analyzed as ordinary switches. Determine whether it is a normally open switch based on the switch information, and parse the normally open switch as a suspected contact switch, otherwise it is analyzed as a disconnect switch. According to the actual opening and closing state of the switch, the open switch is analyzed as a suspected contact switch, and the closed switch is analyzed as a disconnect switch. Then analyze the suspected contact switch. If the same switch belongs to different low-voltage areas, then the switch is a contact switch, otherwise it is an ordinary switch.

[0044] Through the above logic, the interconnecting switches in the low-voltage area are analyzed.

[0045] S105. Analysis of contact switch position.

[0046] Relying on the access equipment grid topology data and equipment inventory data, combined with the low-voltage interconnection switch identification data analyzed in the previous step, the location of the low-voltage interconnection switch in the substation is determined through topological analysis.

[0047] S106. Perform load transfer analysis.

[0048] According to the position of the low-voltage interconnecting switch in the substation determined in the previous step, the load transfer path analysis is performed in combination with the equipment inventory data and real-time operation data to determine whether there is a situation where the line load is too high or the user's electricity demand cannot be met during the load transfer process of the interconnecting switch. If so, it means that the transfer conditions of the interconnecting switch are not met, and the transfer path through the interconnecting switch is not a feasible path, so as to ensure the reliability of the load transfer process.

[0049] S107. Selection of low-voltage transfer path.

[0050] Based on the load transfer path analysis, the low-voltage transfer path selection and low-voltage connection equivalence are performed. If the low-voltage transfer path is located at the head end of the substation, step S108 is executed, and if the low-voltage transfer path is located at the end of the substation, step S109 is executed.

[0051] S108, the low voltage power supply equipment is equivalent to the opposite side distribution transformer, the reliability parameters use the opposite side distribution transformer parameters, and then execute step S110.

[0052] S109, the tie switch is equivalent to the low-voltage area terminal equipment, the reliability parameters use the parameters of the low-voltage area terminal equipment on the opposite side, and then execute step S110.

[0053] S110, performing power supply reliability calculation to obtain reliability calculation results.

[0054] In this embodiment, relying on the existing reliability analysis and evaluation software, the low-voltage substation equipment parameters, grid topology and equipment coordinate information are integrated to construct the actual operation diagram of the low-voltage substation. Combined with the real-time operation data information of the low-voltage substation and the reliability parameters of the low-voltage substation equipment, the power supply reliability calculation is performed.

[0055] S111. Calculation result display. By analyzing the equipment information, grid topology and equipment coordinate information, a real-time low-voltage area operation diagram is automatically generated.

[0056] Based on virtual modeling technology, the grid topology data, equipment inventory data and real-time operation data of the actual operation of the low-voltage substation in the power grid are used to construct a low-voltage substation power supply reliability assessment model, and the power supply reliability calculation considering the low-voltage transfer is carried out to improve the existing power supply reliability calculation method and more effectively reflect the power supply reliability rate of the actual operating power grid.

[0057] The above method is based on virtual modeling technology. It uses the grid topology data, equipment inventory data and real-time operation data of the actual operation of the low-voltage substation in the power grid to construct a low-voltage substation power supply reliability assessment model, and perform power supply reliability calculation considering low-voltage transfer, so as to improve the existing power supply reliability calculation method and more effectively reflect the power supply reliability rate of the actual operating power grid.

[0058] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A method for calculating power supply reliability considering low-voltage transfer, characterized in that: The following steps are involved: Obtain real-time low-voltage area basic data and operation data, the basic data including actual operation grid topology data and ledger data of low-voltage area equipment; Obtain fault information of each low-voltage area equipment; Based on the ledger data and fault information, power supply reliability parameters are calculated according to equipment type; Perform topological analysis based on the actual operation grid topology data and ledger data of the low-voltage area equipment to find the low-voltage contact switch and its location in the low-voltage area; Based on the position of the low-voltage contact switch in the low-voltage area, a feasible load transfer path is determined in combination with the account data and operation data; Based on the location of the feasible load transfer path, the power supply reliability is calculated. Specifically: if the feasible load transfer path is located at the head end of the substation, the low-voltage transfer equipment is equivalent to the opposite distribution transformer, and the reliability parameters use the parameters of the opposite distribution transformer to calculate the power supply reliability; if the low-voltage transfer path is located at the end of the substation, the connecting switch is equivalent to the low-voltage substation terminal equipment, and the reliability parameters use the parameters of the opposite low-voltage substation terminal equipment to calculate the power supply reliability.

2. The power supply reliability calculation method considering low-voltage transfer according to claim 1 is characterized in that: The low-voltage substation equipment includes distribution transformers, pole-mounted transformers, overhead lines, cable sections, circuit breakers, disconnectors, load switches and low-voltage users.

3. The power supply reliability calculation method considering low voltage transfer according to claim 1 is characterized in that: The operation data include active power, reactive power and power factor at the head end of the substation area and power data of users at the end of the substation area.

4. The power supply reliability calculation method considering low-voltage transfer according to claim 1 is characterized in that: The fault information includes the faulty device name, faulty device ID, fault occurrence time, fault duration, and the number of users affected by the fault.

5. The power supply reliability calculation method considering low-voltage transfer according to claim 1 is characterized in that: The power supply reliability parameters include equipment failure rate and equipment failure repair time.

6. The power supply reliability calculation method considering low voltage transfer according to claim 1 is characterized in that: The specific steps of finding the low voltage contact switch are: The switch information is analyzed based on the actual operation grid topology data. According to the different switch types, the switches are divided into ordinary switches, T-type switches, V-type switches and three-position load switches. The T-type switches, V-type switches and three-position load switches are separated according to the switch components through data analysis, and the separated components are analyzed as ordinary switches. According to whether the switch is normally open, the normally open switch is analyzed as a suspected contact switch. According to the actual opening and closing state of the switch, the open switch is analyzed as a suspected contact switch. The suspected connecting switch is analyzed. If the same switch belongs to different low-voltage areas, then the switch is a connecting switch, otherwise it is an ordinary switch.

7. The power supply reliability calculation method considering low-voltage transfer according to claim 1 is characterized in that: The feasible load transfer path meets the following conditions: during the load transfer process, the line load of the tie switch is not too high or the user's electricity demand cannot be met.

8. The power supply reliability calculation method considering low-voltage transfer according to claim 1 is characterized in that: When calculating power supply reliability, the low-voltage substation equipment parameters, grid topology and equipment coordinate information are integrated to construct the actual operation diagram of the low-voltage substation. The final power supply reliability is calculated by combining the real-time operation data of the low-voltage substation and the power supply reliability parameters of the low-voltage substation equipment.

9. The power supply reliability calculation method considering low voltage transfer according to claim 1 is characterized in that: The method further includes: The result of the power supply reliability calculation is displayed.

10. An electronic device, characterized in that: include: one or more processors; Memory; and One or more programs stored in a memory, wherein the one or more programs include instructions for executing the power supply reliability calculation method according to any one of claims 1-9.

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