A method, device, electronic equipment, and storage medium for sensing low-voltage tripping in distribution transformers.

Abstract

This application provides a method, device, electronic equipment, and storage medium for sensing low-voltage tripping of distribution transformers. The method first calculates the load drop of the distribution network based on the distribution network load data before and after the main grid fault. When the load drop reaches a set condition, it is considered that there is a low-voltage tripping in the distribution network. Then, it monitors all the sudden load drop alarm signals of the distribution area within a certain period of time. For the distribution area with alarm signals, it detects the three-phase current of the distribution area after the sudden load drop. When the three-phase current is low to a certain level, it is considered that the distribution area has experienced low-voltage tripping, that is, the distribution transformer corresponding to the distribution area is the distribution transformer that has experienced low-voltage tripping.

Description

Technical Field

[0001] This invention relates to distribution network dispatching technology, specifically to a method, device, electronic equipment, and storage medium for sensing low-voltage tripping of distribution transformers. Background Technology

[0002] "Low-voltage tripping" is a protection mechanism used in power systems and electrical equipment. It automatically disconnects the circuit when the voltage is lower than a set safety value to prevent damage to electrical equipment due to low voltage. Typically, a low-voltage trip unit is used to monitor the voltage. When the voltage is lower than a preset threshold, the tripping mechanism is triggered to disconnect the circuit.

[0003] In power systems, distribution network operation and dispatch control is a crucial link. Especially after a main grid fault is repaired, medium-voltage distribution transformers may experience low-voltage tripping, resulting in the transformers not restoring normal power supply. Consequently, low-voltage users may not have their power restored, while high-voltage power supply has already resumed. However, in such situations, main grid dispatchers and customer service personnel may mistakenly believe that all users have had their power restored after the main grid fault is repaired, when in reality some low-voltage users still haven't had their power restored. Therefore, it is urgent to promptly inspect distribution transformers that haven't had their power restored after a main grid fault to ensure that all low-voltage users can have their power restored as quickly as possible. Summary of the Invention

[0004] Based on this, the present invention aims to propose a method, device, electronic equipment and storage medium for sensing low-voltage tripping of distribution transformers, to monitor load changes and metering automation low-voltage switch faults when main grid faults occur, so as to promptly detect low-voltage tripping faults of medium and low voltage distribution transformers and issue alarms.

[0005] In a first aspect, the present invention proposes a method for sensing low-voltage tripping in distribution transformers, comprising:

[0006] Obtain distribution network load data within the immediate timeframe before and after a main network failure;

[0007] The load drop of the distribution network before and after the main network fault is calculated based on the distribution network load data. When the load drop meets the first set condition, it is determined that there is a low voltage tripping phenomenon in the distribution network, and the low voltage tripping analysis process is initiated.

[0008] The low-voltage trip analysis process includes:

[0009] Obtain load drop alarm signals from all transformer substations in the distribution network that have low-voltage tripping faults within the second time range before and after a main grid failure.

[0010] For transformer substations with load drop alarm signals, the three-phase current after the load drop occurs is measured. When the three-phase current of the substation meets the second set condition, the transformer corresponding to that substation is identified as the transformer that has experienced low-voltage tripping.

[0011] Furthermore, obtaining distribution network load data within the immediate timeframe before and after a main network failure includes:

[0012] The distribution network load data were obtained 1 minute before the main network failure, 2 minutes after the failure, 5 minutes after the failure, and 10 minutes after the failure.

[0013] Furthermore, the load drop in the distribution network before and after the main grid failure is calculated based on the distribution network load data, including:

[0014] The distribution network load data 2 minutes, 5 minutes, and 10 minutes after the fault are subtracted from the distribution network load data 1 minute before the fault to obtain three distribution network load drop values.

[0015] Furthermore, the first set condition includes at least two of the three distribution network load drop values ​​being higher than the load drop threshold.

[0016] Furthermore, the acquisition of load drop alarm signals for all distribution transformer areas within the second time frame before and after the main network failure includes:

[0017] Obtain load drop alarm signals from all transformer areas between 5 minutes before and 50 minutes after the main network failure.

[0018] Furthermore, the second set condition includes that the three-phase current of the transformer area where the load drop occurs is lower than the current threshold.

[0019] In a second aspect, the present invention provides a low-voltage tripping sensing device for distribution transformers, comprising:

[0020] The first data acquisition module is used to acquire distribution network load data within the first time range before and after the main network failure;

[0021] The low-voltage tripping analysis module is used to calculate the load drop of the distribution network before and after the main network fault based on the distribution network load data. When the load drop meets the first set condition, it is determined that there is a low-voltage tripping phenomenon in the distribution network and the low-voltage tripping analysis process is entered.

[0022] The low-voltage trip analysis process includes:

[0023] Obtain load drop alarm signals from all transformer substations in the distribution network that have low-voltage tripping faults within the second time range before and after a main grid failure.

[0024] For transformer substations with load drop alarm signals, the three-phase current after the load drop occurs is measured. When the three-phase current of the substation meets the second set condition, the transformer corresponding to that substation is identified as the transformer that has experienced low-voltage tripping.

[0025] Thirdly, the present invention provides an electronic device including a memory storing computer-executable instructions and a processor, wherein when the computer-executable instructions are executed by the processor, the device performs the various steps of the distribution transformer low-voltage trip sensing method provided in the first aspect.

[0026] Fourthly, the present invention provides a readable storage medium storing a computer-executable program that, when executed, can implement the various steps of the distribution transformer low-voltage trip sensing method provided in the first aspect.

[0027] As can be seen from the above technical solutions, the present invention has the following beneficial effects:

[0028] This invention provides a method, device, electronic equipment, and storage medium for detecting low-voltage tripping in distribution transformers. The detection method first calculates the load drop in the distribution network based on the load data before and after a main grid fault. When the load drop reaches a set condition, it is considered that a low-voltage trip has occurred in the distribution network. Then, it monitors all transformer area load drop alarm signals that occur within a certain time period. For transformer areas with alarm signals, it measures the three-phase current of the transformer area after the load drop. When the three-phase current drops to a certain level, it is considered that a low-voltage trip has occurred in that transformer area. Therefore, it is possible to locate the transformer area corresponding to the transformer that has experienced a low-voltage trip. The method provided by this invention automatically obtains low-voltage switch faults within a specific time period by monitoring the distribution network load changes before and after a main grid fault. It efficiently and accurately locates low-voltage tripping in distribution transformers from both the power supply side and the power consumption side. When a large-scale power outage occurs due to a main grid fault and power is restored, it can monitor whether any transformers have experienced low-voltage tripping immediately, greatly improving the work efficiency of relevant personnel. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0030] Figure 1 This is a flowchart illustrating the implementation of the low-voltage tripping sensing method for distribution transformers provided in this application embodiment;

[0031] Figure 2 This is a schematic diagram of the structure of the low-voltage tripping sensing device for distribution transformers provided in the embodiments of this application;

[0032] Figure 3 This is an electronic device architecture diagram provided for an embodiment of this application. Detailed Implementation

[0033] 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, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] Grid voltage can fluctuate due to various reasons (such as sudden load changes, line faults, and generator equipment failures). When the voltage drops below a safe threshold, it triggers low-voltage tripping. Therefore, timely detection and handling of low-voltage tripping faults to ensure a stable power supply is one of the important guarantees for the stable operation of the power system. In addition, the large-scale integration of distributed energy sources such as solar and wind power has made the operation of the distribution system more complex, placing higher demands on fault detection and management. Currently, there is no efficient means to use information technology to monitor the distribution network for low-voltage tripping when a fault occurs in the main grid.

[0035] In view of this, the following embodiments of the present invention will provide a method, device, electronic device and storage medium for sensing low-voltage tripping of distribution transformers, which can promptly and proactively sense low-voltage tripping faults in medium and low-voltage distribution transformers, more effectively improve the operating efficiency and reliability of the main distribution network system, and reduce maintenance costs and power outage time.

[0036] See Figure 1 One embodiment of this application provides a method for sensing low-voltage tripping in a distribution transformer, comprising the following steps:

[0037] Step S110. Obtain the distribution network load data within the first time range before and after the main network failure.

[0038] Specifically, electricity is generated at power plants, transmitted through the high-voltage main grid to substations, then stepped down by the substations and transmitted to end users through the distribution network. The main grid is responsible for long-distance, high-voltage transmission, while the distribution network is responsible for short-distance, low-voltage distribution. Faults in the main grid may cause fluctuations in the voltage and frequency of the distribution network, which in turn may cause load fluctuations. User equipment may malfunction due to voltage fluctuations.

[0039] In this step, the distribution network load data acquired within a certain time range before and after the main grid fault will be used to perform load drop analysis on the distribution network. Smart meters and power sensors can be installed at various nodes of the distribution network. These devices can collect load data such as voltage, current, and power in real time. Alternatively, SCADA systems or DTUs can be used for data collection. The time range of the distribution network load data to be acquired is determined based on the specific time of the main grid fault. For example, data for one hour before and after the fault.

[0040] Step S120. Calculate the load drop of the distribution network before and after the main network fault based on the distribution network load data. When the load drop meets the first set condition, it is determined that there is a low-voltage tripping phenomenon in the distribution network, and the process of low-voltage tripping analysis in step S130 is initiated.

[0041] In this step, the load drop in the distribution network can be measured by using the average load over a period of time before the fault as the baseline load, calculating the load change after the fault, and finding the maximum load drop. Alternatively, it can involve determining several load sampling times before and after a main grid fault, acquiring the distribution network load data at the specified sampling times, and then analyzing the load fluctuations of the distribution network before and after the main grid fault. Load drop can be measured using indicators such as load drop value and drop percentage. Typically, a specific load drop threshold needs to be set; exceeding this threshold is considered a low-voltage tripping fault in the distribution network.

[0042] Step S130. The low-voltage trip analysis process includes:

[0043] Obtain load drop alarm signals from all transformer substations in the distribution network that have low-voltage tripping faults within the second time range before and after a main grid failure.

[0044] For transformer substations with load drop alarm signals, the three-phase current after the load drop occurs is measured. When the three-phase current of the substation meets the second set condition, the transformer corresponding to that substation is identified as the transformer that has experienced low-voltage tripping.

[0045] Specifically, a distribution transformer area is a basic unit in a power system. A distribution transformer area typically covers a certain range of users, including residential, commercial, and small industrial users. The area supplied by a distribution transformer is a distribution transformer area. The power supply quality and reliability of a distribution transformer area directly depend on the operating condition of the distribution transformer. The distribution network has a wider coverage area, and the distribution transformer area is the basic unit of the distribution network. Therefore, when a low-voltage tripping fault is located in a certain distribution network, it is not possible to determine which specific distribution transformer has experienced the low-voltage tripping fault, and further analysis is required.

[0046] In this step, the distribution network where the low-voltage tripping fault occurred has been identified through the aforementioned steps, that is, the power supply range of the power source has been determined. The operation status of the equipment in the downstream power supply range can be analyzed based on the load fluctuations on the power supply side. When the distribution network load on the power supply side drops, it can be assumed that the downstream equipment may experience a power outage. That is, when the upstream power load fluctuation exceeds a certain threshold, the change in the three-phase current after the sudden drop in the load of the transformer area can be used to infer that a low-voltage tripping fault has occurred in the downstream transformer, thereby triggering an alarm.

[0047] In a further embodiment, step S110 includes the following steps:

[0048] The distribution network load data were obtained 1 minute before the main network failure, 2 minutes after the failure, 5 minutes after the failure, and 10 minutes after the failure.

[0049] The load fluctuation sampling times are 1 minute before the main grid failure, 2 minutes after the failure, 5 minutes after the failure, and 10 minutes after the failure, to obtain the distribution network load data corresponding to each sampling time.

[0050] In some embodiments, distribution network load data can be obtained by integrating data from multiple systems such as automation, main grid EMS system, and distribution network GIS system to establish an integrated main and distribution network model. That is, grid operation data is obtained from various power systems, and based on different types of power outage data, measurement data, equipment parameters, etc. obtained from different systems, the power supply path of "main grid-distribution network-low voltage power consumption side" is relied upon. The data types and topology are used to process and splice the data to obtain a complete structure of power supply from the main grid power supply side to the downstream of the power source. In the process of topology tracing for the main and distribution network structure, all power supply ranges under the power supply source can be traced through the upstream and downstream hierarchical structure of the grid topology relationship.

[0051] Specifically, the system integrates power grid operation data from the main grid EMS and distribution network GIS systems. Based on the data type and topology, it maps and associates the boundaries of multi-source heterogeneous data with boundary devices in the main grid model and distribution network model, connecting and splicing them together to construct a mesh topology connection relationship covering both the main grid and distribution network, forming a mesh model structure. This mesh model allows the power supply range to be located from the power source point. The power grid operation data includes main grid fault data from the integrated dispatching master station system, main grid load data, main grid model and connection relationships, distribution network model and connection relationships, and low-voltage switch data on the user side of the metering system. The boundaries of multi-source heterogeneous data include outgoing switches within the main grid and outgoing switches of the distribution network feeders. In the actual physical environment, these are devices belonging to the same equipment but with logically related models built on two different system architectures.

[0052] In a further embodiment, step S120, which calculates the load drop of the distribution network before and after the main network fault based on the distribution network load data, includes the following process:

[0053] The distribution network load drops are calculated by subtracting the distribution network load data 2 minutes, 5 minutes, and 10 minutes after the fault from the distribution network load data 1 minute before the fault.

[0054] Specifically, the distribution network load data one minute before the fault is used as the baseline load. The load difference between the distribution network load data two minutes, five minutes, and ten minutes after the fault and the baseline load is calculated. This yields three load difference values: the distribution load drop one minute before the fault and two minutes after, the distribution load drop one minute before the fault and five minutes after, and the distribution load drop one minute before the fault and ten minutes after. This reflects the load drop in the distribution network before and after the main grid fault, i.e., the amount of distribution network load tripping. When the distribution load fluctuation exceeds a certain threshold, it is considered that the distribution transformers within the distribution network's power supply range may experience low-voltage tripping.

[0055] In a further embodiment, when the distribution network load drop is represented by the above three load differences, the first setting condition in step S120 includes at least two of the three distribution network load drop values ​​being higher than the load drop threshold. In this embodiment, the load drop threshold is set to 50MW. That is, when there are two or more distribution network load drop values ​​higher than 50MW, it is determined that there is a low-voltage tripping phenomenon in the distribution network. If there is only one or no distribution network load drop value higher than the set load drop threshold, it is considered that there is no low-voltage tripping phenomenon in the distribution network, and the low-voltage tripping detection ends.

[0056] After determining that there is a low-voltage trip in the distribution network, an alarm can be pushed to the operation and maintenance personnel, and the load drop alarm signals of all transformer areas in the distribution network with low-voltage trip fault can be obtained.

[0057] In a further embodiment, the load drop alarm signals that occur in all transformer areas within a certain time range are searched within the distribution network coverage area. In the embodiments of this application, the sampling period is taken as 5 minutes before the main network failure and 50 minutes after the failure.

[0058] In some embodiments, if the sum of the three-phase currents before the load of the transformer area decreases is greater than 0.6A, or the single-phase current is greater than 0.2A, it is considered that a load drop has occurred in the transformer area, and the metering system will send an alarm signal. For transformer areas where a load drop occurs, if all three-phase currents are lower than the set current threshold, the embodiment of this application takes the set current threshold as 0.06A, which can determine that a low-voltage tripping phenomenon has occurred in the downstream distribution transformer, and push a low-voltage tripping alarm to the operation and maintenance personnel.

[0059] In a further embodiment, if the dispatcher sets a phased power restoration time in the low-voltage trip alarm information, the dispatcher monitors whether the phased power restoration time is consistent with the main grid fault recovery time corresponding to the low-voltage trip fault. If they are inconsistent, the dispatcher uses the set phased power restoration time as the dividing point to obtain the distribution network load data before and after the set power restoration time and repeats the analysis of the aforementioned steps S120~S130. Conversely, if the phased power restoration time is consistent with the main grid fault time, the low-voltage trip sensing analysis is not performed.

[0060] The above embodiments provide a method for detecting low-voltage tripping of distribution transformers. By monitoring the changes in distribution network load before and after a main grid fault, the method automatically obtains low-voltage switch faults within a specific time period. It can efficiently and accurately locate low-voltage tripping of distribution transformers from both the power supply side and the power consumption side. When a large-scale power outage occurs due to a main grid fault and power supply is restored, it can monitor whether there is low-voltage tripping of distribution transformers as soon as possible, which greatly improves the work efficiency of relevant personnel.

[0061] The methods and related apparatuses mentioned in the above embodiments are described with reference to the method flowcharts and / or structural diagrams provided in the embodiments of this application. Specifically, each block of the method flowchart and / or structural diagram, as well as combinations of blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing device, generate instructions for implementing the process. Figure 1 A schematic diagram of one or more processes and / or structures. Figure 1 The computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 A schematic diagram of one or more processes and / or structures. Figure 1 The functions specified in one or more boxes. These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable apparatus for implementing the process. Figure 1 A process or multiple processes and / or structures illustrate the steps of the functions specified in one or more boxes.

[0062] The above-disclosed embodiments describe in detail a method for sensing low-voltage tripping of a distribution transformer. The above-disclosed method can be implemented using various types of devices. Therefore, the present invention also discloses an apparatus corresponding to the above method. Specific embodiments are given below for detailed description.

[0063] See Figure 2 One embodiment of the present invention provides a low-voltage trip sensing device for a distribution transformer, comprising:

[0064] The first data acquisition module 210 is used to acquire distribution network load data within the first time range before and after the main network failure;

[0065] The low-voltage tripping analysis module 220 is used to calculate the load drop of the distribution network before and after the main network fault based on the distribution network load data. When the load drop meets the first set condition, it is determined that there is a low-voltage tripping phenomenon in the distribution network and the low-voltage tripping analysis process is entered.

[0066] The low-voltage trip analysis process includes:

[0067] Obtain load drop alarm signals from all transformer substations in the distribution network that have low-voltage tripping faults within the second time range before and after a main grid failure.

[0068] For transformer substations with load drop alarm signals, the three-phase current after the load drop occurs is measured. When the three-phase current of the substation meets the second set condition, the transformer corresponding to that substation is identified as the transformer that has experienced low-voltage tripping.

[0069] The device provided in this application embodiment has the same implementation principle and technical effect as the aforementioned method embodiment. For the sake of brevity, any parts not mentioned in the device embodiment can be referred to the corresponding content in the aforementioned method embodiment.

[0070] The following embodiments illustrate the application of this method to a computer device. It is understood that the computer device can be any device with computing and processing capabilities, including but not limited to servers or personal laptops. In one embodiment, the computer device can be an application server, which can be a server used to run the application under test.

[0071] See Figure 3 This document illustrates a hardware block diagram of an electronic device intended to represent various forms of digital computers, such as laptops, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframes, and other suitable computers. The electronic device may also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the present application described and / or claimed herein.

[0072] like Figure 3 As shown, the electronic device includes: at least one processor 1, at least one communication interface 2, at least one memory 3, and at least one communication bus 4;

[0073] In this embodiment of the application, the number of processor 1, communication interface 2, memory 3, and communication bus 4 is at least one, and processor 1, communication interface 2, and memory 3 communicate with each other through communication bus 4;

[0074] Processor 1 may be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement embodiments of the present invention.

[0075] Memory 3 may include high-speed RAM, and may also include non-volatile memory, such as at least one disk storage device;

[0076] The memory stores a program, which the processor can call. The program is used to implement the various processing steps of the aforementioned distribution transformer low-voltage trip sensing scheme.

[0077] This invention also provides a readable storage medium storing a computer program thereon. When the computer program is executed by a processor, it implements various processing flows of the distribution transformer low-voltage tripping sensing scheme provided in any possible implementation of the above embodiments and / or in combination with the embodiments.

[0078] The invention has been described in particular detail above with respect to possible scenarios, and those skilled in the art will recognize that the invention can be practiced through other embodiments. Specific naming of components, capitalization of terms, attributes, data structures, or any other programming or structural aspects are not mandatory or important, and the mechanisms or features of implementing the invention may have different names, forms, or procedures. The system can be implemented through a combination of hardware and software (as described), entirely through hardware elements, or entirely through software elements. The specific division of functions among the various system components described herein is merely exemplary and not mandatory; rather, the functions performed by a single system component can be performed by multiple components, or the functions performed by multiple components can be performed by a single component.

[0079] Those skilled in the art should understand that the various steps of the disclosed methods can be implemented using general-purpose computing devices. They can be centralized on a single computing device or distributed across a network of multiple computing devices. Optionally, they can be implemented using device-executable program code, which can then be stored in a storage device for execution by the computing device. Alternatively, they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Therefore, the embodiments disclosed in this invention are not limited to any specific hardware and software combination.

[0080] The programs (also referred to as programs, software, software applications, or code) executable by these computing devices include machine instructions of a programmable processor and can be implemented using high-level procedural and / or object-oriented programming languages, and / or assembly / machine languages. As used herein, the terms “machine-readable medium” and “computer-readable medium” refer to any computer program product, device, and / or apparatus (e.g., disk, optical disk, memory, programmable logic device (PLD)) used to provide machine instructions and / or data to a programmable processor, including machine-readable media that receive machine instructions as machine-readable signals. The term “machine-readable signal” refers to any signal used to provide machine instructions and / or data to a programmable processor.

[0081] Certain aspects of this invention include the process steps and instructions described herein in algorithmic form. It should be noted that the process steps and instructions of this invention can be implemented in software, firmware, and / or hardware, and when implemented in software, they can be downloaded, stored on various operating systems and operated from said platforms.

[0082] Those skilled in the art will understand that the structures shown in the figures are merely block diagrams of some structures related to the present application and do not constitute a limitation on the terminal device to which the present application is applied. Specific terminal devices may include more or fewer components than those shown in the figures, or combine certain components, or have different component arrangements.

[0083] In the description of this specification, the use of terms such as "one embodiment," "some embodiments," "example," "specific example," or "possible design," etc., refers to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0084] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0085] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for sensing low-voltage tripping in distribution transformers, characterized in that, include: Obtain distribution network load data within the immediate timeframe before and after a main network failure; The load drop of the distribution network before and after the main network fault is calculated based on the distribution network load data. When the load drop meets the first set condition, it is determined that there is a low voltage tripping phenomenon in the distribution network, and the low voltage tripping analysis process is entered. The low-voltage trip analysis process includes: Obtain load drop alarm signals from all transformer substations in the distribution network that have low-voltage tripping faults within the second time range before and after a main grid failure. For transformer substations with load drop alarm signals, the three-phase current after the load drop occurs is measured. When the three-phase current of the substation meets the second set condition, the transformer corresponding to that substation is identified as the transformer that has experienced low-voltage tripping.

2. The method according to claim 1, characterized in that, The acquisition of distribution network load data within the first time range before and after the main network failure includes: The distribution network load data were obtained 1 minute before the main network failure, 2 minutes after the failure, 5 minutes after the failure, and 10 minutes after the failure.

3. The method according to claim 2, characterized in that, The calculation of the load drop in the distribution network before and after a main grid fault based on the distribution network load data includes: The distribution network load data 2 minutes, 5 minutes, and 10 minutes after the fault are subtracted from the distribution network load data 1 minute before the fault to obtain three distribution network load drop values.

4. The method according to claim 3, characterized in that, The first setting condition includes at least two of the three distribution network load drop values ​​being higher than the load drop threshold.

5. The method according to claim 1, characterized in that, The acquisition of load drop alarm signals for all transformer areas within the second time range before and after the main network failure includes: Obtain load drop alarm signals from all transformer areas between 5 minutes before and 50 minutes after the main network failure.

6. The method according to claim 1, characterized in that, The second setting condition includes that the three-phase current of the transformer area where the load drop occurs is lower than the current threshold.

7. The method according to claim 1, characterized in that, The method further includes: Obtain the phased power restoration time of the main grid fault. When the phased power restoration time is inconsistent with the main grid fault recovery time, take the phased power restoration time as the dividing point, obtain the distribution network load data within the third time range before and after the phased power restoration time, and perform the step of calculating the load drop of the distribution network before and after the main grid fault based on the distribution network load data.

8. A low-voltage trip sensing device for distribution transformers, characterized in that, include: The first data acquisition module is used to acquire distribution network load data within the first time range before and after the main network failure; The low-voltage tripping analysis module is used to calculate the load drop of the distribution network before and after the main network fault based on the distribution network load data. When the load drop meets the first set condition, it is determined that there is a low-voltage tripping phenomenon in the distribution network and the low-voltage tripping analysis process is entered. The low-voltage trip analysis process includes: Obtain load drop alarm signals from all transformer substations in the distribution network that have low-voltage tripping faults within the second time range before and after a main grid failure. For transformer substations with load drop alarm signals, the three-phase current after the load drop occurs is measured. When the three-phase current of the substation meets the second set condition, the transformer corresponding to that substation is identified as the transformer that has experienced low-voltage tripping.

9. An electronic device, characterized in that, It includes a memory storing computer-executable instructions and a processor, which, when executed by the processor, causes the device to perform the distribution transformer low-voltage trip sensing method as described in any one of claims 1 to 7.

10. A readable storage medium, characterized in that, It stores a computer-executable program that, when executed, can implement the distribution transformer low-voltage trip sensing method as described in any one of claims 1 to 7.

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