Power distribution area voltage out-of-limit cause analysis method and device

Abstract

The invention relates to the technical field of power system analysis, and particularly provides a power distribution area voltage out-of-limit cause analysis method and device, and the method comprises the steps: extracting corresponding feature data when a voltage out-of-limit event occurs in a power distribution area; analyzing a voltage out-of-limit cause of the power distribution area based on the characteristic data; wherein the characteristic data comprises a load three-phase unbalance degree, a distribution transformer load rate, a power factor, a load fluctuation rate, a measured voltage value, a maximum phase and minimum phase voltage difference, voltage out-of-limit event occurrence time, a reactive power, a measured voltage value out-of-limit frequency and a measured voltage value out-of-limit duration time. According to the technical scheme provided by the invention, the distribution transformer side voltage cause is identified, and a foundation is laid for comprehensively improving the electric energy quality level of a distribution transformer area.

Description

Technical Field

[0001] The present invention relates to the technical field of power system analysis, and in particular to a method and device for analyzing causes of voltage over-limit in a distribution station area. Background Art

[0002] Currently, distribution networks are facing severe power quality issues. High penetration rates of renewable energy generation, widespread coverage of electric vehicle charging facilities, and the massive access of various new loads have exacerbated the nonlinear and random fluctuations in the source and load within distribution substations, leading to increasingly prominent power quality issues such as voltage and three-phase imbalance. Furthermore, the high cyclicality of load fluctuations within substations, and the significant variations in these issues between substations within the same power supply area, further complicate the management of voltage over-limit issues within these substations.

[0003] Currently, many locations serving as pilot sites for smart terminals in substations have deployed tens of thousands of monitoring points, providing a preliminary understanding of voltage levels across distribution substations. Building on the existing achievements in substation terminal development, the advantages of edge computing in substation smart terminals are being leveraged to analyze the causes of voltage over-limit issues, effectively improving substation power quality and meeting the grid's economical operation and high-quality electricity needs of users.

[0004] For diverse substations, it is necessary to extract key features for voltage over-limit issues from massive amounts of data and identify their causes. There are numerous distribution substations, the power supply environment is complex, and the equipment levels and operating conditions vary significantly across substations. Furthermore, the nonlinear and random nature of distributed power sources and the large-scale access of new loads further contribute to the diversity of substation characteristics and power quality issues. Furthermore, there are strong correlations between different types of monitoring data, and the correlations between different data and power quality issues in different substations are complex and difficult to directly characterize, further exacerbating the difficulty of identifying the causes. Summary of the Invention

[0005] In order to overcome the above-mentioned defects, the present invention proposes a method and device for analyzing the causes of voltage over-limit in a distribution station area.

[0006] In a first aspect, a method for analyzing causes of voltage over-limit in a distribution station area is provided, the method comprising:

[0007] Extract the characteristic data corresponding to the voltage over-limit event in the distribution station area;

[0008] Analyze the cause of voltage exceeding the limit in the distribution station area based on the characteristic data;

[0009] Among them, the characteristic data includes: three-phase load imbalance, distribution transformer load rate, power factor, load fluctuation rate, measured voltage value, maximum phase and minimum phase voltage difference, voltage limit event occurrence time, reactive power, measured voltage value limit number of times, and measured voltage value limit duration.

[0010] Preferably, the criterion for determining whether a voltage over-limit event occurs in the distribution station area is as follows:

[0011]

[0012] In the above formula, U a ,U b ,U c are the three-phase voltage measurement values ​​measured by the intelligent distribution transformer terminal on the busbar of the distribution station area, V is the voltage unit, t is the duration of a single voltage limit-exceeding event, and h is the time unit.

[0013] Preferably, after obtaining the three-phase voltage measurement value data measured by the intelligent distribution transformer terminal on the distribution substation bus, the data availability is verified.

[0014] Furthermore, the verification data availability includes:

[0015] Take the day as the data verification cycle, compare the three-phase voltage measurement values ​​of the intelligent distribution transformer terminal installed on the same busbar and other types of instruments. If the difference between the three-phase voltage measurement values ​​of the intelligent distribution transformer terminal installed on the same busbar and other types of instruments meets the following requirements: min{a a ,a b ,a c}>x%, then the data of this verification period is unavailable, otherwise, the data of this verification period is available, where a a ,a b ,a c These are the differences between the a, b, and c phase voltage measurements made by the intelligent distribution transformer terminal and other types of instruments installed on the same busbar, respectively. x is the preset difference coefficient.

[0016] Furthermore, the differences between the a, b, and c phase voltage measurements measured by the intelligent distribution transformer terminal and other types of instruments installed on the same bus are as follows:

[0017] make The intelligent distribution transformer terminal and other instruments installed on the same busbar measure Differences between phase voltage measurements as follows:

[0018]

[0019] In the above formula, The data measured by the intelligent distribution transformer terminal and other instruments installed on the same bus Phase-to-phase voltage measurements.

[0020] Furthermore, the verification data availability includes:

[0021] The data verification cycle is daily. If the three-phase voltage measurement value measured by the intelligent distribution transformer terminal is zero and lasts for more than 2 hours, the data of this verification cycle is unavailable. Otherwise, the data of this verification cycle is available.

[0022] Preferably, the load three-phase imbalance γ is as follows:

[0023]

[0024] The distribution transformer load factor ρ is as follows:

[0025]

[0026] The power factor cosλ is as follows:

[0027]

[0028] In the above formula, I max , I min are the maximum and minimum phase currents, P aj ,P bj ,P cj are the actual operating power of phases a, b, and c at node j, respectively, P N is the rated power of the transformer, N is the set of nodes in the line, P and Q are the total active and total reactive power of the three-phase load respectively.

[0029] Preferably, the analyzing the cause of voltage exceeding a limit in the distribution station area based on the characteristic data includes:

[0030] When the three-phase unbalance degree of the load is less than the first threshold, the voltage in the distribution area exceeds the limit because the distribution transformer gear is unreasonable or the power supply facilities and capacity configuration cannot meet the needs of the existing load;

[0031] When the power factor is less than the second threshold, the voltage in the distribution area exceeds the limit because the voltage at the transformer winding distribution junction is unbalanced;

[0032] When the load fluctuation rate is higher than the third threshold, the voltage over-limit in the distribution station area is caused by the power factor not meeting the standard;

[0033] When the load factor of the distribution transformer is greater than the fourth threshold, the voltage in the distribution area exceeds the limit because of poor neutral grounding contact;

[0034] When the measured voltage value is lower than the fifth threshold, the voltage in the distribution area exceeds the limit because the distribution transformer is overloaded;

[0035] When the measured voltage value exceeds the lower limit a large number of times and the duration of the exceeding limit exceeds the sixth threshold, the voltage exceeding the limit in the distribution station area is caused by a gateway meter failure;

[0036] When the load is not zero and the voltage is discontinuously above the lower limit, the voltage in the distribution area exceeds the limit because of poor contact of the distribution transformer pile head;

[0037] When the three-phase unbalance degree of the load is lower than the seventh threshold and the voltage difference between the maximum phase and the minimum phase is greater than the eighth threshold, the voltage over-limit in the distribution station area is caused by a transient fault of the distribution transformer;

[0038] When the voltage over-limit event occurs at a holiday time, the voltage over-limit event in the distribution station area is caused by the unbalanced three-phase load;

[0039] When the reactive power is lower than the ninth threshold, the voltage in the distribution station area exceeds the limit because the power load surges during holidays.

[0040] In a second aspect, a device for analyzing causes of voltage exceeding a limit in a distribution station area is provided, the device comprising:

[0041] An extraction module is used to extract characteristic data corresponding to voltage over-limit events occurring in distribution station areas;

[0042] An analysis module, configured to analyze causes of voltage exceeding a limit in a distribution station area based on the characteristic data;

[0043] Among them, the characteristic data includes: three-phase load imbalance, distribution transformer load rate, power factor, load fluctuation rate, measured voltage value, maximum phase and minimum phase voltage difference, voltage limit event occurrence time, reactive power, measured voltage value limit number of times, and measured voltage value limit duration.

[0044] In a third aspect, a computer device is provided, comprising: one or more processors;

[0045] The processor is configured to execute one or more programs;

[0046] When the one or more programs are executed by the one or more processors, the method for analyzing causes of voltage exceeding a limit in a distribution station area is implemented.

[0047] In a fourth aspect, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed, the method for analyzing the cause of voltage over-limit in a distribution station area is implemented.

[0048] The above one or more technical solutions of the present invention have at least one or more of the following beneficial effects:

[0049] The present invention provides a method and device for analyzing the causes of voltage over-limit in a distribution substation, including: extracting characteristic data corresponding to a voltage over-limit event in a distribution substation; analyzing the causes of voltage over-limit in the distribution substation based on the characteristic data; wherein the characteristic data include: three-phase load imbalance, distribution transformer load rate, power factor, load fluctuation rate, measured voltage value, maximum phase and minimum phase voltage difference, time of occurrence of voltage over-limit event, reactive power, number of times the measured voltage value exceeds the limit, and duration of time the measured voltage value exceeds the limit. The technical solution provided by the present invention accurately extracts relevant data features of voltage and power quality problems based on multi-source monitoring information, conducts research on voltage and power quality problem feature mining technology, can support lean management of power quality in the distribution network, and further assist substation managers in dealing with various power quality problems, providing a guarantee for improving power quality in the distribution substation. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a flow chart of the main steps of the method for analyzing the cause of voltage over-limit in a distribution station area according to an embodiment of the present invention. DETAILED DESCRIPTION

[0051] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0052] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0053] As disclosed in the background technology, the current distribution network faces severe power quality issues. High penetration rates of renewable energy generation, high coverage of electric vehicle charging facilities, and the massive access of various new load types have exacerbated the nonlinear and random fluctuations in the source and load of distribution stations, leading to increasingly prominent power quality issues such as voltage and three-phase imbalance. Furthermore, the high cyclicality of load variations in distribution stations, and the significant differences in these issues between different stations within the same power supply area, further complicate the management of voltage over-limit issues in these stations.

[0054] Currently, many locations serving as pilot sites for smart terminals in substations have deployed tens of thousands of monitoring points, providing a preliminary understanding of voltage levels across distribution substations. Building on the existing achievements in substation terminal development, the advantages of edge computing in substation smart terminals are being leveraged to analyze the causes of voltage over-limit issues, effectively improving substation power quality and meeting the grid's economical operation and high-quality electricity needs of users.

[0055] For diverse substations, it is necessary to extract key features for voltage over-limit issues from massive amounts of data and identify their causes. There are numerous distribution substations, the power supply environment is complex, and the equipment levels and operating conditions vary significantly across substations. Furthermore, the nonlinear and random nature of distributed power sources and the large-scale access of new loads further contribute to the diversity of substation characteristics and power quality issues. Furthermore, there are strong correlations between different types of monitoring data, and the correlations between different data and power quality issues in different substations are complex and difficult to directly characterize, further exacerbating the difficulty of identifying the causes.

[0056] In order to improve the above-mentioned problems, the present invention provides a method and device for analyzing the causes of voltage over-limit in a distribution substation, including: extracting characteristic data corresponding to a voltage over-limit event in a distribution substation; analyzing the causes of voltage over-limit in the distribution substation based on the characteristic data; wherein the characteristic data include: three-phase load imbalance, distribution transformer load rate, power factor, load fluctuation rate, measured voltage value, maximum phase and minimum phase voltage difference, time of occurrence of voltage over-limit event, reactive power, number of times the measured voltage value exceeds the limit, and duration of the measured voltage value exceeding the limit. The technical solution provided by the present invention accurately extracts relevant data features of voltage and power quality problems based on multi-source monitoring information, conducts research on voltage and power quality problem feature mining technology, can support lean management of power quality in the distribution network, and further assist substation managers in dealing with various power quality problems, and provide guarantees for improving power quality in distribution substations.

[0057] The above scheme is described in detail below.

[0058] Example 1

[0059] See attached Figure 1 , Figure 1 FIG. 1 is a flow chart showing the main steps of a method for analyzing the causes of voltage over-limit in a distribution station area according to an embodiment of the present invention. Figure 1 As shown, the method for analyzing the cause of voltage over-limit in a distribution station area in an embodiment of the present invention mainly includes the following steps:

[0060] Step S101: extracting characteristic data corresponding to a voltage over-limit event occurring in a distribution station area;

[0061] Step S102: Analyze the cause of voltage exceeding the limit in the distribution station area based on the characteristic data;

[0062] Among them, the characteristic data includes: three-phase load imbalance, distribution transformer load rate, power factor, load fluctuation rate, measured voltage value, maximum phase and minimum phase voltage difference, voltage limit event occurrence time, reactive power, measured voltage value limit number of times, and measured voltage value limit duration.

[0063] In this embodiment, the criteria for determining whether a voltage over-limit event occurs in the distribution station area are as follows:

[0064]

[0065] In the above formula, U a ,U b ,U c are the three-phase voltage measurement values ​​measured by the intelligent distribution transformer terminal on the busbar of the distribution station area, V is the voltage unit, t is the duration of a single voltage limit-exceeding event, and h is the time unit.

[0066] In this embodiment, after obtaining the three-phase voltage measurement value data measured by the intelligent distribution transformer terminal on the distribution substation bus, the data availability is verified.

[0067] In one embodiment, verifying data availability includes:

[0068] Take the day as the data verification cycle, compare the three-phase voltage measurement values ​​of the intelligent distribution transformer terminal installed on the same busbar and other types of instruments. If the difference between the three-phase voltage measurement values ​​of the intelligent distribution transformer terminal installed on the same busbar and other types of instruments meets the following requirements: min{a a ,a b ,a c}>x%, then the data of this verification period is unavailable, otherwise, the data of this verification period is available, where a a ,a b ,a c These are the differences between the a, b, and c phase voltage measurements made by the intelligent distribution transformer terminal and other types of instruments installed on the same busbar, respectively. x is the preset difference coefficient.

[0069] In one embodiment, the differences between the a, b, and c phase voltage measurement values ​​measured by the intelligent distribution transformer terminal and other types of instruments installed on the same bus are as follows:

[0070] make The intelligent distribution transformer terminal and other instruments installed on the same busbar measure Differences between phase voltage measurements as follows:

[0071]

[0072] In the above formula, The data measured by the intelligent distribution transformer terminal and other instruments installed on the same bus Phase-to-phase voltage measurements.

[0073] In one embodiment, verifying data availability includes:

[0074] The data verification cycle is daily. If the three-phase voltage measurement value measured by the intelligent distribution transformer terminal is zero and lasts for more than 2 hours, the data of this verification cycle is unavailable. Otherwise, the data of this verification cycle is available.

[0075] In this embodiment, the load three-phase imbalance γ is as follows:

[0076]

[0077] The distribution transformer load factor ρ is as follows:

[0078]

[0079] The power factor cosλ is as follows:

[0080]

[0081] In the above formula, I max , I min are the maximum and minimum phase currents, P aj ,P bj ,P cj are the actual operating power of phases a, b, and c at node j, respectively, P N is the rated power of the transformer, N is the set of nodes in the line, P and Q are the total active and total reactive power of the three-phase load respectively.

[0082] In this embodiment, analyzing the cause of voltage exceeding a limit in the distribution station area based on the characteristic data includes:

[0083] When the three-phase unbalance degree of the load is less than the first threshold, the voltage in the distribution area exceeds the limit because the distribution transformer gear is unreasonable or the power supply facilities and capacity configuration cannot meet the needs of the existing load;

[0084] When the power factor is less than the second threshold, the voltage in the distribution area exceeds the limit because the voltage at the transformer winding distribution junction is unbalanced;

[0085] When the load fluctuation rate is higher than the third threshold, the voltage over-limit in the distribution station area is caused by the power factor not meeting the standard;

[0086] When the load factor of the distribution transformer is greater than the fourth threshold, the voltage in the distribution area exceeds the limit because of poor neutral grounding contact;

[0087] When the measured voltage value is lower than the fifth threshold, the voltage in the distribution area exceeds the limit because the distribution transformer is overloaded;

[0088] When the measured voltage value exceeds the lower limit a large number of times and the duration of the exceeding limit exceeds the sixth threshold, the voltage exceeding the limit in the distribution station area is caused by a gateway meter failure;

[0089] When the load is not zero and the voltage is discontinuously above the lower limit, the voltage in the distribution area exceeds the limit because of poor contact of the distribution transformer pile head;

[0090] When the three-phase unbalance degree of the load is lower than the seventh threshold and the voltage difference between the maximum phase and the minimum phase is greater than the eighth threshold, the voltage over-limit in the distribution station area is caused by a transient fault of the distribution transformer;

[0091] When the voltage over-limit event occurs at a holiday time, the voltage over-limit event in the distribution station area is caused by the unbalanced three-phase load;

[0092] When the reactive power is lower than the ninth threshold, the voltage in the distribution station area exceeds the limit because the power load surges during holidays.

[0093] Example 2

[0094] Based on the same inventive concept, the present invention further provides a device for analyzing causes of voltage over-limit in a distribution station area, the device comprising:

[0095] An extraction module is used to extract characteristic data corresponding to voltage over-limit events occurring in distribution station areas;

[0096] An analysis module, configured to analyze causes of voltage exceeding a limit in a distribution station area based on the characteristic data;

[0097] Among them, the characteristic data includes: three-phase load imbalance, distribution transformer load rate, power factor, load fluctuation rate, measured voltage value, maximum phase and minimum phase voltage difference, voltage limit event occurrence time, reactive power, measured voltage value limit number of times, and measured voltage value limit duration.

[0098] Preferably, the criterion for determining whether a voltage over-limit event occurs in the distribution station area is as follows:

[0099]

[0100] In the above formula, U a ,U b ,U c are the three-phase voltage measurement values ​​measured by the intelligent distribution transformer terminal on the busbar of the distribution station area, V is the voltage unit, t is the duration of a single voltage limit-exceeding event, and h is the time unit.

[0101] Preferably, after obtaining the three-phase voltage measurement value data measured by the intelligent distribution transformer terminal on the distribution substation bus, the data availability is verified.

[0102] Furthermore, the verification data availability includes:

[0103] Take the day as the data verification cycle, compare the three-phase voltage measurement values ​​of the intelligent distribution transformer terminal installed on the same busbar and other types of instruments. If the difference between the three-phase voltage measurement values ​​of the intelligent distribution transformer terminal installed on the same busbar and other types of instruments meets the following requirements: min{a a ,a b ,a c}>x%, then the data of this verification period is unavailable, otherwise, the data of this verification period is available, where a a ,a b ,a c These are the differences between the a, b, and c phase voltage measurements made by the intelligent distribution transformer terminal and other types of instruments installed on the same busbar, respectively. x is the preset difference coefficient.

[0104] Furthermore, the differences between the a, b, and c phase voltage measurements measured by the intelligent distribution transformer terminal and other types of instruments installed on the same bus are as follows:

[0105] make The intelligent distribution transformer terminal and other instruments installed on the same busbar measure Differences between phase voltage measurements as follows:

[0106]

[0107] In the above formula, The data measured by the intelligent distribution transformer terminal and other instruments installed on the same bus Phase-to-phase voltage measurements.

[0108] Furthermore, the verification data availability includes:

[0109] The data verification cycle is daily. If the three-phase voltage measurement value measured by the intelligent distribution transformer terminal is zero and lasts for more than 2 hours, the data of this verification cycle is unavailable. Otherwise, the data of this verification cycle is available.

[0110] Preferably, the load three-phase imbalance γ is as follows:

[0111]

[0112] The distribution transformer load rate ρ is as follows:

[0113]

[0114] The power factor cosλ is as follows:

[0115]

[0116] In the above formula, I max , I minare the maximum and minimum phase currents, P aj ,P bj ,P cj are the actual operating power of phases a, b, and c at node j, respectively, P N is the rated power of the transformer, N is the set of nodes in the line, P and Q are the total active and total reactive power of the three-phase load respectively.

[0117] Preferably, the analyzing the cause of voltage exceeding a limit in the distribution station area based on the characteristic data includes:

[0118] When the three-phase unbalance degree of the load is less than the first threshold, the voltage in the distribution area exceeds the limit because the distribution transformer gear is unreasonable or the power supply facilities and capacity configuration cannot meet the needs of the existing load;

[0119] When the power factor is less than the second threshold, the voltage in the distribution area exceeds the limit because the voltage at the transformer winding distribution junction is unbalanced;

[0120] When the load fluctuation rate is higher than the third threshold, the voltage over-limit in the distribution station area is caused by the power factor not meeting the standard;

[0121] When the load factor of the distribution transformer is greater than the fourth threshold, the voltage in the distribution area exceeds the limit because of poor neutral grounding contact;

[0122] When the measured voltage value is lower than the fifth threshold, the voltage in the distribution area exceeds the limit because the distribution transformer is overloaded;

[0123] When the measured voltage value exceeds the lower limit a large number of times and the duration of the exceeding limit exceeds the sixth threshold, the voltage exceeding the limit in the distribution station area is caused by a gateway meter failure;

[0124] When the load is not zero and the voltage is discontinuously above the lower limit, the voltage in the distribution area exceeds the limit because of poor contact of the distribution transformer pile head;

[0125] When the three-phase unbalance degree of the load is lower than the seventh threshold and the voltage difference between the maximum phase and the minimum phase is greater than the eighth threshold, the voltage over-limit in the distribution station area is caused by a transient fault of the distribution transformer;

[0126] When the voltage over-limit event occurs at a holiday time, the voltage over-limit event in the distribution station area is caused by the unbalanced three-phase load;

[0127] When the reactive power is lower than the ninth threshold, the voltage in the distribution station area exceeds the limit because the power load surges during holidays.

[0128] Example 3

[0129] Based on the same inventive concept, the present invention also provides a computer device, which includes a processor and a memory, wherein the memory is used to store a computer program, the computer program includes program instructions, and the processor is used to execute the program instructions stored in the computer storage medium. The processor may be a central processing unit (CPU), or may be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, which is suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions in the computer storage medium to implement the corresponding method flow or corresponding function, so as to implement the steps of the method for analyzing the cause of voltage over-limit in a distribution station area in the above embodiment.

[0130] Example 4

[0131] Based on the same inventive concept, the present invention also provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device for storing programs and data. It can be understood that the computer-readable storage medium here can include both built-in storage media in the computer device and, of course, extended storage media supported by the computer device. The computer-readable storage medium provides a storage space, which stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by the processor are also stored in the storage space. These instructions can be one or more computer programs (including program codes). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk memory. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the steps of a method for analyzing the cause of voltage over-limit in a distribution station area in the above embodiment.

[0132] It will be understood by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0133] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0134] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0135] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0136] 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 it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the scope of protection of the claims of the present invention.

Claims

1. A method for analyzing causes of voltage over-limit in a distribution station area, characterized in that: The method comprises: Extract the characteristic data corresponding to the voltage over-limit event in the distribution station area; Analyze the cause of voltage exceeding the limit in the distribution station area based on the characteristic data; Among them, the characteristic data includes: three-phase load imbalance, distribution transformer load rate, power factor, load fluctuation rate, measured voltage value, maximum phase and minimum phase voltage difference, voltage limit event occurrence time, reactive power, measured voltage value limit number of times, and measured voltage value limit duration.

2. The method according to claim 1, wherein The criteria for determining voltage over-limit events in the distribution station area are as follows: In the above formula, U a ,U b ,U c are the three-phase voltage measurement values ​​measured by the intelligent distribution transformer terminal on the busbar of the distribution station area, V is the voltage unit, t is the duration of a single voltage limit-exceeding event, and h is the time unit.

3. The method according to claim 1, wherein After obtaining the three-phase voltage measurement value data measured by the intelligent distribution transformer terminal on the distribution substation bus, the data availability is verified.

4. The method according to claim 3, wherein The verification data availability includes: Take the day as the data verification cycle, compare the three-phase voltage measurement values ​​of the intelligent distribution transformer terminal installed on the same busbar and other types of instruments. If the difference between the three-phase voltage measurement values ​​of the intelligent distribution transformer terminal installed on the same busbar and other types of instruments meets the following requirements: min{a a ,a b ,a c }>x%, then the data of this verification period is unavailable, otherwise, the data of this verification period is available, where a a ,a b ,a c These are the differences between the a, b, and c phase voltage measurements made by the intelligent distribution transformer terminal and other types of instruments installed on the same busbar, respectively. x is the preset difference coefficient.

5. The method according to claim 4, wherein The differences between the a, b, and c phase voltage measurements of the intelligent distribution transformer terminal and other types of instruments installed on the same bus are as follows: make The intelligent distribution transformer terminal and other instruments installed on the same busbar measure Differences between phase voltage measurements as follows: In the above formula, The data measured by the intelligent distribution transformer terminal and other instruments installed on the same bus Phase-to-phase voltage measurements.

6. The method according to claim 3, wherein The verification data availability includes: The data verification cycle is daily. If the three-phase voltage measurement value measured by the intelligent distribution transformer terminal is zero and lasts for more than 2 hours, the data of this verification cycle is unavailable. Otherwise, the data of this verification cycle is available.

7. The method according to claim 1, wherein The load three-phase imbalance γ is as follows: The distribution transformer load factor ρ is as follows: The power factor cosλ is as follows: In the above formula, I max , I min are the maximum and minimum phase currents, P aj ,P bj ,P cj are the actual operating power of phases a, b, and c at node j, respectively, P N is the rated power of the transformer, N is the set of nodes in the line, P and Q are the total active and total reactive power of the three-phase load respectively.

8. The method according to claim 1, wherein Analyzing the cause of voltage exceeding a limit in the distribution station area based on the characteristic data includes: When the three-phase unbalance degree of the load is less than the first threshold, the voltage in the distribution area exceeds the limit because the distribution transformer gear is unreasonable or the power supply facilities and capacity configuration cannot meet the needs of the existing load; When the power factor is less than the second threshold, the voltage in the distribution area exceeds the limit because the voltage at the transformer winding distribution junction is unbalanced; When the load fluctuation rate is higher than the third threshold, the voltage over-limit in the distribution station area is caused by the power factor not meeting the standard; When the load factor of the distribution transformer is greater than the fourth threshold, the voltage in the distribution area exceeds the limit because of poor neutral grounding contact; When the measured voltage value is lower than the fifth threshold, the voltage in the distribution area exceeds the limit because the distribution transformer is overloaded; When the measured voltage value exceeds the lower limit a large number of times and the duration of the exceeding limit exceeds the sixth threshold, the voltage exceeding the limit in the distribution station area is caused by a gateway meter failure; When the load is not zero and the voltage is discontinuously above the lower limit, the voltage in the distribution area exceeds the limit because of poor contact of the distribution transformer pile head; When the three-phase unbalance degree of the load is lower than the seventh threshold and the voltage difference between the maximum phase and the minimum phase is greater than the eighth threshold, the voltage over-limit in the distribution station area is caused by a transient fault of the distribution transformer; When the voltage over-limit event occurs at a holiday time, the voltage over-limit event in the distribution station area is caused by the unbalanced three-phase load; When the reactive power is lower than the ninth threshold, the voltage in the distribution station area exceeds the limit because the power load surges during holidays.

9. A device based on the method for analyzing causes of voltage over-limit in a distribution station area according to any one of claims 1 to 8, characterized in that: The device comprises: An extraction module is used to extract characteristic data corresponding to voltage over-limit events occurring in distribution station areas; An analysis module, configured to analyze causes of voltage exceeding a limit in a distribution station area based on the characteristic data; Among them, the characteristic data includes: three-phase load imbalance, distribution transformer load rate, power factor, load fluctuation rate, measured voltage value, maximum phase and minimum phase voltage difference, voltage limit event occurrence time, reactive power, measured voltage value limit number of times, and measured voltage value limit duration.

10. A computer device, characterized in that: include: one or more processors; The processor is configured to store one or more programs; When the one or more programs are executed by the one or more processors, the method for analyzing causes of voltage over-limit in a distribution station area according to any one of claims 1 to 8 is implemented.

11. A computer-readable storage medium, characterized in that A computer program is stored thereon, and when the computer program is executed, the method for analyzing causes of voltage over-limit in a distribution station area according to any one of claims 1 to 8 is implemented.

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