A low-voltage power distribution network leakage detection device, monitoring system and monitoring method

Abstract

The application relates to a low-voltage power distribution network leakage detection device, a monitoring system and a monitoring method. The low-voltage power distribution network leakage detection device comprises a controller, a communicator, a current sampler, an image collector, a GPS locator, a fault recorder, a memory and a power supply; the controller is used for receiving current data collected by the current sampler, image data collected by the image collector, recording wave data collected by the fault recorder and communication information transmitted by the communicator, and transmitting communication information through the communicator. The application provides a low-voltage power distribution network leakage detection device, a monitoring system and a monitoring method. The method is based on an edge computing low-voltage distribution network leakage monitoring system and a monitoring method, realizes rapid and accurate detection and real-time positioning of leakage, the data collection, processing and analysis are all provided by the detection device, the power grid resources are not occupied, and the demand of intelligent application is met.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of power distribution network monitoring, in particular to a low-voltage power distribution network leakage detection device, a monitoring system and a monitoring method. BACKGROUND

[0002] The power company of State Grid Corporation of China feedbacks that the phenomenon of hooking electricity stealing is very serious, which leads to high line loss of the transformer area, and the economic benefit of the enterprise is damaged. Hooking electricity stealing occurs from time to time, and it is difficult to discover and deal with it in time, resulting in loss of the benefit of the power grid enterprise. For a long time, there is a lack of effective technical means for monitoring and investigation, which brings many troubles to the power grid enterprise.

[0003] Secondly, at present, line leakage is the pain point and difficulty of safe and economic operation of low-voltage rural power distribution network. The traditional leakage current investigation mainly relies on the experience of staff, which is time-consuming and laborious, and it is difficult to find hidden and occasional leakage. For a long time, there is a lack of effective technical means for monitoring and investigation, which brings many troubles to the power grid enterprise.

[0004] The punishment of electricity stealing behavior is provided in the "Power Supply Business Rules", and the use of the device can provide scientific and strong support for the implementation of the rules.

[0005] Existing scheme one: manual line inspection. Manual line inspection is still the most commonly used way at present. Problem points: (1) Manual inspection is time-consuming and laborious, and it is difficult to find hidden and occasional electricity stealing, and the operation and maintenance personnel are under great pressure; (2) Manual line inspection has poor real-time performance and cannot quickly and accurately locate the electricity stealing point. Existing scheme two: external equipment extracts data from the electric energy meter and the metering master station for analysis. Problem points: (1) Not allowed in principle: In October 2012, the International Organization of Legal Metrology (OIML) issued the IR46 standard, and as a member state, China must also adopt and implement the IR international metrology regulation document of the organization, which requires that the electric energy metering function be independent of other functions, and the legal metrology data should be protected. (2) The metering data of the entire transformer area is large, the algorithm is complex, the data is updated slowly, and the real-time performance is poor, which cannot be processed in time. (3) The metering data is strictly controlled and cannot be easily obtained. (4) The security of the metering data is threatened.

[0006] The patent document with the patent number ZL201910708050.8 discloses an edge computing anti-electricity stealing method and device based on ubiquitous power Internet of Things, which starts from the anomaly of the magnetic field and further judges whether there is electricity stealing behavior. The data required for detection and calculation is still very complex, the data is updated slowly, the real-time performance is poor, and it cannot be processed and located in time.

[0007] Therefore, there is a deficiency in the field, and the inventors need to continue to research and innovate. SUMMARY

[0008] In view of the above deficiencies of the prior art, the purpose of the present application is to provide a low-voltage power distribution network electricity stealing and leakage detection device, a monitoring system and a monitoring method, which can collect current data of a line and image data of the surrounding environment, and quickly determine the location of electricity stealing and leakage when electricity stealing and leakage occurs.

[0009] In order to achieve the above purpose, the present application adopts the following technical solutions:

[0010] A low-voltage power distribution network electricity stealing and leakage detection device comprises a controller, a communicator, a current sampler, an image collector, a GPS locator, a fault recording device, a memory and a power supply.

[0011] The current sampler is used to detect line current data and send the current data to the controller.

[0012] The image collector is used to collect image data of the surrounding environment and send the image data to the controller.

[0013] The communicator is used to receive and send communication information according to the instructions of the controller.

[0014] The GPS locator transmits positioning information to the controller.

[0015] The fault recording device is used to perform fault recording according to the instructions of the controller and feed back fault recording data to the controller.

[0016] The memory is used to store a feature database and is connected to the controller.

[0017] The controller is used to receive the current data collected by the current sampler, the image data collected by the image collector, the recording data collected by the fault recording device and the communication information transmitted by the communicator, and transmit communication information through the communicator.

[0018] The power supply is used to supply power to the controller, the communicator, the image collector and the fault recording device, respectively.

[0019] Preferably, the low-voltage power distribution network electricity stealing and leakage detection device further comprises a temperature and humidity sensor, which is used to detect temperature and humidity data of the surrounding environment and transmit the temperature and humidity data to the controller.

[0020] Preferably, the communicator of the low-voltage power distribution network electricity stealing and leakage detection device is a 4G module.

[0021] Preferably, the power supply of the low-voltage power distribution network electricity stealing and leakage detection device is a solar power supply or a power supply or electricity supply of a power clip.

[0022] A low-voltage power distribution network leakage monitoring system, comprising a monitoring master station, a total measuring device, a plurality of branch measuring devices and a plurality of execution devices;

[0023] The total measuring device and the branch measuring device both adopt the detection device;

[0024] The branch measuring device is installed in each branch line and is used for collecting and sending current data and image data of the line to the total measuring device;

[0025] The total measuring device is installed in the total bus of a transformer area and is used for detecting current data and recording fault wave of the total bus of the transformer area, receiving current data and image data measured by the branch measuring devices and communicating with the monitoring master station;

[0026] The execution device is used for indicating leakage information according to an instruction of the monitoring master station;

[0027] The monitoring master station is used for communicating with the total measuring device and sending a control instruction to the execution device.

[0028] Preferably, the low-voltage power distribution network leakage monitoring system comprises a plurality of branch measuring devices, which are installed in switch cabinet lines, branch box lines and household lines according to installation positions and are arranged according to a tree topology structure;

[0029] The branch measuring device installed in the household line is used for collecting and sending current data and image data of the household line to the branch measuring device installed in the branch box line connected with the household line;

[0030] The branch measuring device installed in the branch box line is used for collecting current data and image data of the branch box line, receiving detection data of the branch measuring device of the household line connected with the branch box line and sending the detection data to the branch measuring device installed in the switch cabinet line connected with the branch box;

[0031] The branch measuring device installed in the switch cabinet line is used for detecting current data and image data of the switch cabinet line, receiving detection data of the branch measuring device of the branch box line connected with the switch cabinet and sending the detection data to the total measuring device on the total bus of the transformer area connected with the switch cabinet.

[0032] A low-voltage power distribution network leakage monitoring method for the monitoring system, comprising the following steps:

[0033] S1, data collection: a plurality of branch measuring devices detect branch measuring current data of electricity consumption of a household line at a predetermined frequency and send the branch measuring current data to a total measuring device; the total measuring device detects total measuring current data of electricity consumption of a transformer area at a predetermined frequency and simultaneously collects the branch measuring current data transmitted by a plurality of branch measuring devices in the transformer area;

[0034] S2. The total measurement device performs current synthesis calculation and determines whether the calculated current value is greater than a first preset value. If yes, proceed to step S4; otherwise, proceed to step S3.

[0035] S3. The total measuring device detects whether there is an abnormal current in the circuit. If yes, proceed to step S4; otherwise, proceed to step S1.

[0036] S4. The total measuring device determines whether the difference between the total measured current data and the sum of several individual measured current data is greater than a second preset value. If yes, then step S5 is executed; if no, then step S1 is executed.

[0037] S5. Feature Judgment: The total measurement device starts current recording and compares it with the load feature data to determine whether the total measurement current data is electricity theft feature data or leakage feature data. If it is electricity theft feature data, then proceed to step S6; if it is leakage feature data, then proceed to step S7.

[0038] S6. Image positioning: Several of the sub-measurement devices respectively collect image data of their respective environments and send the collected image data to the overall measurement device. The overall measurement device summarizes the image data and determines the location of the electricity theft, and then executes step S8.

[0039] S7. Data location: The total measurement device performs multi-level data comparison operations to determine the location of leakage current and executes step S8.

[0040] S8. The location of the electricity theft or the location of the leakage is transmitted to the monitoring master station, and the monitoring master station pushes the information of the location of the electricity theft or the location of the leakage to the execution device.

[0041] In the preferred method for detecting theft and leakage in low-voltage distribution networks, the multi-level data comparison operation is as follows:

[0042] The main measuring device collects all the detection data sent by the sub-measuring devices installed in the switch cabinet circuit, compares the current data of each level of the circuit, compares the current data of each branch of the tree topology, and locates the leakage location.

[0043] In the preferred method for monitoring leakage current in low-voltage distribution networks, the abnormal current is defined as follows: the average current value of the current detected within 10-50ms is calculated, and the current value detected in this instance exceeding the average current value by 12A or more is considered the abnormal current.

[0044] In the preferred method for monitoring electricity theft and leakage in low-voltage distribution networks, the first preset value and the second preset value are adjusted upwards and downwards as the ambient temperature and humidity increase and decrease, respectively; the data tables of the first preset value and the second preset value changing with the temperature and humidity are stored in the memory of the main measuring device and the memory of the sub-measuring device, respectively.

[0045] Compared with existing technologies, the present invention provides a low-voltage distribution network theft and leakage detection device, monitoring system and monitoring method. The low-voltage distribution network theft and leakage monitoring system and monitoring method based on edge computing can realize rapid and accurate detection and real-time location of theft and leakage. The data acquisition, processing and analysis are all done by the detection device provided by the present invention, and do not occupy power grid resources, thus meeting the needs of intelligent applications. Attached Figure Description

[0046] Figure 1 This is a structural block diagram of the leakage current detection device provided by the present invention;

[0047] Figure 2 This is a structural block diagram of the electricity theft and leakage monitoring system provided by the present invention;

[0048] Figure 3 This is a schematic diagram of an embodiment of the tree topology of the electricity theft and leakage monitoring system provided by the present invention;

[0049] Figure 4 This is a flowchart of the low-voltage power distribution network theft and leakage monitoring method provided by the present invention.

[0050] GPS (Global Positioning System), flash (Flash Memory) Detailed Implementation

[0051] To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0052] Example 1

[0053] Please see Figure 1 The present invention provides a low-voltage power distribution network leakage detection device, comprising: a controller 51, a communicator 52, a current sampler 53, an image acquisition device 54, a GPS locator 55, a fault recorder 56, a memory 57, and a power supply 58.

[0054] The current sampler 53 is used to detect line current data and send the current data to the controller 51; the preferred embodiment of the current sampler 53 is a current transformer, and more preferably a bushing-type current transformer.

[0055] The image acquisition device 54 is used to acquire image data of the surrounding environment and send the image data to the controller 51. The image acquisition device 54 is mainly used to acquire images of the surrounding environment. The preferred embodiment is a digital camera, which can convert the image data into digital data and transmit it to the controller 51 for further processing.

[0056] The communicator 52 is used to receive and send communication information according to the instructions of the controller 51. The communicator 52 can be a wired communicator or a wireless communicator. As a preferred option, the communicator 52 in this embodiment is a wireless communicator. At the same time, an independent communication protocol needs to be matched during communication. The communication protocol is not limited in this embodiment, as long as it can ensure that data is not mistransmitted or cannot be transmitted.

[0057] The GPS locator 55 transmits the location information to the controller 51. Because some of the leakage detection devices are installed on the inbound line, but the inbound line is not completely determined, a positioning device is needed to locate the device and transmit the location information to the controller 51.

[0058] The fault recorder 56 is used to record fault waveforms according to the instructions of the controller 51 and feed the fault waveform data back to the controller 51; the fault recorder 56 is not limited in this embodiment.

[0059] The memory 57 is used to store the feature database and is connected to the controller 51; the memory 57 is preferably a flash memory.

[0060] The controller 51 is used to receive the current data collected by the current sampler 53, the image data collected by the image collector 54, the waveform data collected by the fault waveform recorder 56, and the communication information transmitted by the communicator 52, and to transmit the communication information through the communicator 52; the controller 51 is preferably a logic controller 51; the logic controller 51 is preferably a PLC (Programmable Logic Controller) controller 51;

[0061] The power supply 58 is used to supply power to the controller 51, the communicator 52, the image acquisition unit 54, and the fault recorder 56, respectively. Specifically, the power supply 58 can be an independent power supply or a mains power supply; the independent power supply is a rechargeable lithium battery or solar power, and the mains power supply is connected to the power grid. In this embodiment,

[0062] Specifically, the leakage current detection device is mainly used to detect the current in the line and to record fault waveforms when leakage current occurs. During use, part of the leakage current detection device is used in the main testing device, and another part is used in the sub-testing devices. The main testing device is used to summarize the detection data from the sub-testing devices and perform corresponding processing. Therefore, the controller 51 of the leakage current detection device needs to have certain logic processing functions. Of course, the leakage current detection device can also be used independently; this invention does not impose any limitations.

[0063] During operation, the current sampler 53 detects the current value data of the line in real time and transmits it to the controller 51. The controller 51 then determines whether there is abnormal current data. If so, it activates the fault recorder 56 to record the fault waveform and feeds the recorded waveform data back to the controller 51. The controller 51 determines whether there is any leakage current based on the feature database. If leakage current is found, the controller 51 drives the image acquisition device 54 to collect image data of the surrounding environment. The controller 51 then determines whether there is any leakage current in the environment of this section of the line and reports the analysis results. Alternatively, the leakage current detection device of this section can not make a judgment, and the detection data can be uploaded for the host computer to determine whether there is any leakage current. The host computer can be a server or a higher-level leakage current detection device, i.e., the overall measurement device.

[0064] As a preferred embodiment, this invention also includes a temperature and humidity sensor for detecting the temperature and humidity data of the surrounding environment and transmitting the temperature and humidity data to the controller 51. Specifically, because changes in ambient temperature and humidity can affect the leakage current of the circuit, the controller 51 will determine whether leakage current theft has occurred based on the ambient temperature and humidity.

[0065] As a preferred embodiment, the communicator 52 is a 4G module. Specifically, for ease of deployment, the communicator 52 uses wireless communication, preferably 4G module communication. Furthermore, it can select or set connection targets, which helps in building a communication network. The specific 4G module is not limited, as long as it performs the above functions.

[0066] As a preferred embodiment, in this embodiment, the power source 58 is either solar-powered or powered by a power-collecting clip. The solar power supply uses a solar power generation device to supply power to the device, while the power-collecting clip uses a device to obtain power from the power grid. In a further embodiment, the power-collecting clip uses a puncture pin to collect power.

[0067] Example 2

[0068] Please refer to the following: Figures 2-4The present invention also provides a low-voltage power distribution network theft and leakage monitoring system, comprising: a monitoring master station 1, a main measuring device 2, several sub-measuring devices 3 and several execution devices 4;

[0069] Both the total measuring device 2 and the sub-measuring device 3 employ the aforementioned detection device;

[0070] The sub-measurement device 3 is installed in each branch line and is used to collect and send the current data and image data of this line to the main measurement device 2.

[0071] The main measurement device 2 is installed in the bus of the transformer area and is used to detect current data and record fault waveforms of the bus of the transformer area. At the same time, it receives current data and image data measured by several sub-measurement devices 3 and communicates with the monitoring master station 1.

[0072] The execution device 4 is used to indicate electricity theft information according to the instructions of the detection master station. The execution device 4 is a manually operated device. The monitoring master station sends corresponding instructions to the execution device 4 to indicate electricity theft information. The electricity theft information includes information such as whether the line is normal, whether electricity theft has occurred, and the location of electricity theft.

[0073] The monitoring master station 1 is used to communicate with the overall measuring device 2 and send control commands to the execution device 4. The monitoring master station can be a server with a display and host, or other devices with similar functions.

[0074] The differences between the main testing device 2 and the sub-testing devices 3 are as follows: First, in terms of communication, the main testing device 2 communicates with several sub-testing devices 3, while the sub-testing devices 3 only communicate with the main testing device 2. Second, regarding line monitoring, the main testing device 2 typically monitors the lines of the entire transformer substation, which generally uses a three-phase four-wire (three live and one neutral) line. The sub-testing devices 3 monitor the lines entering the residential area, which generally use a two-phase two-wire (one live and one neutral) line. Therefore, the current sampler 53 in the main testing device 2 needs to simultaneously monitor the current of four lines, while the current sampler in the sub-testing device 3 needs to monitor the current of two lines. Furthermore, the controller 51 in the sub-testing device 3 does not perform logical data analysis; the logical analysis is handled by the controller 51 in the main testing device 2.

[0075] Accordingly, please refer to the following: Figure 4 The present invention also provides a method for monitoring electricity theft and leakage in a low-voltage distribution network for the aforementioned monitoring system, comprising the following steps:

[0076] S1. Data acquisition: Several sub-testing devices 3 detect the sub-testing current data of the electricity consumption of the household's line at a predetermined frequency and send it to the main testing device 2; the main testing device 2 detects the main testing current data of the electricity consumption of the transformer area at a predetermined frequency, and at the same time summarizes the sub-testing current data transmitted by several sub-testing devices 3 in the transformer area.

[0077] S2. The total measuring device 2 performs current synthesis calculation and determines whether the calculated current value is greater than a first preset value. If yes, proceed to step S4; otherwise, proceed to step S3. This step is used to determine whether there is a possibility of leakage. The final determination of whether there is leakage will be made qualitatively in step S5. The formula for the synthesis calculation is:

[0078] I A +I B +I C +I N =I0;

[0079] Among them, I A I B I C I N These are the current values ​​for phases A, B, C, and N. Phases A, B, and C are the current values ​​of the live wires, and phase N is the current value of the neutral wire. Because the currents flow in different directions, if the detected I... A I B I C When I is positive, N The result is a negative value, and the sum of these values ​​is I0, which is the calculated current value obtained by the combined calculation. However, under normal circumstances, there may be some leakage. Therefore, it is necessary to set the first preset value. Only when the calculated value is greater than the first preset value can it be determined that leakage may have occurred.

[0080] S3. The total measuring device 2 detects whether there is an abnormal current in the line. If yes, proceed to step S4; if no, proceed to step S1. The abnormal current is a rapidly changing current. The rapidly changing current is defined as the measured current value exceeding the average current value over a certain period of time before the current measurement by a certain amount. The certain period of time and the certain amount of data are specifically set according to the actual situation. It should be noted that the electricity theft judgment in this step is a preliminary judgment, and the final determination is based on the identification in step S5.

[0081] S4. The total measuring device 2 determines whether the current difference between the total measured current data and the sum of several individual measured current data is greater than a second preset value. If yes, then step S5 is executed; if no, then step S1 is executed. Specifically, the formula for calculating the current difference is:

[0082]

[0083] Among them, I z The total current value measured by the total measuring device 2; I n The measured current value is the nth current value among N branch lines (the order of the nth position is not limited, as long as the current of all branch lines is finally added together, and the current data of each branch line is only included in the calculation once); I j The current difference value;

[0084] S5. Feature Judgment: The total measurement device 2 starts recording the current waveform and compares it with the load feature data to determine whether the total measured current data is electricity theft feature data or leakage feature data. If it is electricity theft feature data, proceed to step S6; if it is leakage feature data, proceed to step S7. The electricity theft feature is a short-term abnormal current caused by the start-up of the electricity theft device, which stabilizes at a certain current value after a certain period of time. The electricity theft feature data is a set of different types of electricity theft feature data. The leakage feature data includes continuous leakage feature data, short-term leakage feature data, and electric shock leakage feature data.

[0085] S6. Image positioning: Several of the sub-measurement devices 3 respectively collect image data of their respective environments and send the collected image data to the total measurement device 2. The total measurement device 2 summarizes the image data and determines the location of the electricity theft, and executes step S8.

[0086] S7. Data positioning: The total measurement device 2 performs multi-level data comparison operation to determine the leakage location and executes step S8; specifically, the multi-level data comparison is to summarize and analyze the data of devices installed in different locations.

[0087] S8. The location of the electricity theft or the location of the leakage is transmitted to the monitoring master station 1, and the monitoring master station 1 pushes the information of the location of the electricity theft or the location of the leakage to the execution device 4.

[0088] As a preferred embodiment, in this case, the abnormal current is defined as follows: the average current value detected within 10-50ms is calculated, and the current value detected in this instance exceeds the average current value by 12A or more, thus constituting an abnormal current. Specifically, the predetermined frequency is preferably 4000Hz, meaning 4000 current values ​​are detected within 1 second, the average current value is calculated within 10-50ms, and the current value detected in this instance is considered abnormal if it exceeds the average current value by 12A. Generally, the current of electricity theft is quite obvious, varying by several amperes or tens of amperes. However, leakage current is more complex, typically involving mA-level data. Therefore, the method provided by this invention first performs a combined calculation of the current of each branch line within the distribution area to determine if leakage current has occurred, and then judges whether electricity theft has occurred. If neither occurs, no action is taken; if one of the conditions is met, location determination begins.

[0089] Specifically, the collection of electricity theft characteristic data includes:

[0090] When the air conditioner is turned on: the abnormal current is 44A, the sudden current lasts for 280ms, and the current is 6A after steady state.

[0091] When starting a single-phase motor: the abnormal current is 26A, the sudden current duration is 240ms, and the current after steady state is 9A.

[0092] When the aerator in the fishpond is turned on: the abnormal current is 40A, the sudden current lasts for 30ms, and the current is 5A after the steady state.

[0093] When turning on the kettle: the abnormal current is 12A, the sudden current lasts for 30ms, and the current is 12A after the steady state.

[0094] The above four types are only some of the electricity theft characteristic data listed in this invention, and are not limited thereto. In specific implementation, the collection of electricity theft characteristic data may include electricity theft characteristic data of multiple devices.

[0095] In general, the abnormal current value generated by electricity theft is above 12A. Therefore, as long as the current value detected this time exceeds 12A or more compared with the average current value, it can be preliminarily identified. However, for a more refined identification, a two-step identification can be used. The first step is to determine whether the current value detected this time exceeds 12A or more compared with the average current value. The second step is to determine whether the current value detected this time exceeds 5A or more compared with the average current value under steady-state conditions.

[0096] As a preferred embodiment, in this case, the first preset value and the second preset value are adjusted upwards as the ambient temperature and humidity increase and downwards as the ambient temperature and humidity decrease; the data tables of the first preset value and the second preset value changing with the temperature and humidity are stored in the memory 57 of the total measuring device 2 and the memory 57 of the sub-measuring device 3, respectively. The data tables are obtained based on big data statistics or scientific research, and are not limited here. Generally, it is sufficient to store the corresponding data tables of the first preset value and the second preset value changing with the temperature and humidity in the total measuring device 2 and the sub-measuring device 3. It should be noted that the data tables can be linear tables or numerical tables, and are not limited here.

[0097] Please refer to this carefully. Figure 3 As a preferred embodiment, in this embodiment, several of the aforementioned sub-measurement devices 3 are installed according to their installation locations as switch cabinet lines, branch box lines, and inlet lines, and are arranged according to a tree topology; specifically, the installation here refers to installation between the upper-level position and the current-level position of the corresponding installation location in the figure, or installation in... Figure 3 The location indicated by the middle arrow;

[0098] The measuring device 3 installed on the inlet line is used to collect and send the current data and image data of the household line to the measuring device 3 installed on the branch box line connected to the household line.

[0099] The measuring device 3 installed in the branch box line is used to collect current data and image data of the branch box line, receive the detection data of the measuring device 3 of the incoming line connected to the branch box line, and send it to the measuring device 3 of the switch cabinet line connected to the branch box.

[0100] The sub-testing device 3 installed on the switch cabinet line is used to detect the current data and image data of the switch cabinet line, and to receive the detection data of the sub-testing device 3 of the branch box line connected to the switch cabinet, and send it to the main testing device 2 on the substation bus connected to the switch cabinet.

[0101] As a preferred embodiment, the multi-level data comparison operation is as follows:

[0102] The main measuring device 2 aggregates the detection data sent by all the sub-measuring devices 3 installed in the switchgear circuits, compares the current data of each level of the circuit, and compares the current data of each branch of the tree topology to locate the leakage point. This multi-level data comparison is mainly aimed at determining the specific location of the leakage, enabling a clear understanding of the current situation of each branch of the circuit. The comparison is performed level by level, or level by level using the composite calculation, or level by level initiating current recording and then judging based on load characteristic data, or simply the main measuring device 2 performs level by level composite calculation for each branch to ultimately determine the leakage point.

[0103] As a preferred embodiment, the execution device 4 is a mobile phone, which is convenient to use and responds quickly.

[0104] It is understood that those skilled in the art can make equivalent substitutions or modifications to the technical solution and inventive concept of the present invention, and all such substitutions or modifications should fall within the protection scope of the appended claims.

Claims

1. A low-voltage power distribution network theft and leakage monitoring system, characterized in that, include: The system consists of a main monitoring station, a central measuring device, several sub-measuring devices, and several execution devices. Both the main testing device and the sub-testing device adopt a low-voltage power distribution network leakage detection device, which includes a controller, a communicator, a current sampler, an image acquisition device, a GPS locator, a fault recorder, a memory, and a power supply. The current sampler is used to detect line current data and send the current data to the controller; The image acquisition device is used to acquire surrounding image data and send the image data to the controller; The communicator is used to receive and send communication information according to the instructions of the controller; The GPS locator is used to transmit positioning information to the controller; The fault recorder is used to record fault waveforms according to the instructions of the controller and feed back the fault waveform data to the controller. The memory is used to store the feature database and is connected to the controller; The controller is configured to receive current data collected by the current sampler, image data collected by the image acquisition unit, waveform data collected by the fault recorder, and communication information transmitted by the communicator, and to transmit the communication information through the communicator; the controller is also configured to determine whether there is abnormal current data based on the line current data, and if so, to start the fault recorder to perform fault waveform recording, and to determine whether there is leakage current based on the feature database, and if there is leakage current, to drive the image acquisition unit to collect image data of the surrounding environment, and to determine whether there is leakage current in the environment of this section of the line based on the image data of the surrounding environment; The power supply is used to supply power to the controller, the communicator, the image acquisition unit, the GPS locator, and the fault recorder, respectively. The plurality of measuring devices are installed in switch cabinet lines, branch box lines and household lines according to their installation locations, and are arranged in a tree topology. The plurality of measuring devices detect the current data of the electricity consumption of their respective household lines at a predetermined frequency and send it to the main measuring device. The measuring device installed in the household line is used to collect and send the current data and image data of the household line to the measuring device installed in the branch box line connected to the household line. The measuring device installed on the branch box line is used to collect current data and image data of the branch box line, receive detection data from the measuring device of the incoming line connected to the branch box line, and send it to the measuring device installed on the switch cabinet line connected to the branch box; the measuring device installed on the switch cabinet line is used to detect current data and image data of the switch cabinet line, and receive detection data from the measuring device of the branch box line connected to the switch cabinet, and send it to the main measuring device on the substation bus connected to the switch cabinet. The total measurement device is installed in the transformer area bus and is used to record fault waveforms on the bus of the transformer area and detect the total current data of the power consumption of the transformer area at a predetermined frequency. At the same time, it summarizes the measured current data and image data transmitted by several of the sub-measurement devices in the transformer area and communicates with the monitoring master station. The total measurement device is also used to perform current synthesis calculations. When the calculated current value is greater than a first preset value and the current difference between the total measured current data and the sum of several individual measured current data is greater than a second preset value, and when the calculated current value is not greater than the first preset value but an abnormal current exists in the line and the current difference between the total measured current data and the sum of several individual measured current data is greater than the second preset value, the total measurement device initiates current recording and compares it with load characteristic data to determine whether the total measured current data is electricity theft characteristic data or leakage characteristic data. The abnormal current is defined as a current value exceeding the average current value of 12A or more. The average current value is the average value of the current detected within 10ms-50ms. The electricity theft characteristic data includes abnormal current data, sudden current duration data, and steady-state current data. The leakage current characteristic data includes continuous leakage current characteristic data, short-time leakage current characteristic data, and electric shock leakage current characteristic data. The calculated current value is the sum of the current values ​​of the four phases A, B, C, and N. Phases A, B, and C are the current values ​​of the live wires, and phase N is the current value of the neutral wire. The overall measuring device is also used to, when the overall measured current data is electricity theft characteristic data, aggregate the image data collected by several of the sub-measuring devices from their respective environments and determine the electricity theft location; when the overall measured current data is leakage characteristic data, aggregate the detection data sent by all the sub-measuring devices installed in the switch cabinet circuit, compare the current data of each level of the circuit, compare the current data of each branch of the tree topology, and locate the leakage location; the overall measuring device transmits the electricity theft location or the leakage location to the monitoring master station, and the monitoring master station pushes the electricity theft location or the leakage location to the execution device; The execution device is used to indicate information about electricity theft and leakage according to the instructions of the monitoring master station; The monitoring master station is used to communicate with the overall measurement device and send control commands to the execution device.

2. The low-voltage distribution network theft and leakage monitoring system according to claim 1, characterized in that, The detection device also includes a temperature and humidity sensor for detecting the temperature and humidity data of the surrounding environment and transmitting the temperature and humidity data to the controller.

3. The low-voltage distribution network theft and leakage monitoring system according to claim 1, characterized in that, The communicator is a 4G module.

4. The low-voltage distribution network theft and leakage monitoring system according to claim 1, characterized in that, The power source is solar power or power supplied by a power clip.

5. A method for monitoring leakage current in a low-voltage distribution network using the monitoring system according to any one of claims 1-4, characterized in that, Including the following steps: S1. Data Acquisition: Several sub-testing devices detect the sub-testing current data of the electricity consumption of the household's line at a predetermined frequency and send it to the main testing device; the main testing device detects the main testing current data of the electricity consumption of the transformer area at a predetermined frequency, and at the same time summarizes the sub-testing current data transmitted by several sub-testing devices in the transformer area. S2. The total measurement device performs current synthesis calculation and determines whether the calculated current value is greater than a first preset value. If yes, proceed to step S4; otherwise, proceed to step S3. S3. The total measuring device detects whether there is an abnormal current in the circuit. If yes, then proceed to step S4; if no, then proceed to step S1. The abnormal current is a current whose value exceeds the average current value of 12A or more. The average current value is the average value of the current detected within 10ms-50ms. S4. The total measurement device determines whether the current difference between the total measured current data and the sum of several individual measured current data is greater than a second preset value. If yes, then step S5 is executed; if no, then step S1 is executed. S5. Feature Judgment: The total measurement device starts current recording and compares it with the load feature data to determine whether the total measured current data is electricity theft feature data or leakage feature data. If it is electricity theft feature data, then proceed to step S6; if it is leakage feature data, then proceed to step S7. The electricity theft feature data includes abnormal current data, sudden current duration data, and steady-state current data. S6. Image positioning: Several of the sub-measurement devices respectively collect image data of their respective environments and send the collected image data to the overall measurement device. The overall measurement device summarizes the image data and determines the location of the electricity theft, and then executes step S8. S7. Data location: The total measurement device performs multi-level data comparison operations to determine the location of leakage current and executes step S8. S8. The location of the electricity theft or the location of the leakage is transmitted to the monitoring master station, and the monitoring master station pushes the information of the location of the electricity theft or the location of the leakage to the execution device; The multi-level data comparison operation is as follows: The main measuring device collects all the detection data sent by the sub-measuring devices installed in the switch cabinet circuit, compares the current data of each level of the circuit, compares the current data of each branch of the tree topology, and locates the leakage location.

6. The method for monitoring theft and leakage in low-voltage distribution networks according to claim 5, characterized in that, The first preset value and the second preset value are adjusted upwards as the ambient temperature and humidity rise and downwards as the ambient temperature and humidity fall; the data tables of the first preset value and the second preset value changing with the temperature and humidity are stored in the memory of the total measuring device and the memory of the sub-measuring device, respectively.

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