A method for monitoring leakage current of an electrical device

Abstract

The present application relates to the technical field of electric variable measurement, and in particular to a leakage monitoring method of an electrical device, comprising: obtaining input current and residual current of the electrical device in a current time period and historical leakage data; analyzing leakage causes of the electrical device according to the historical leakage data to obtain historical leakage characteristics and an importance degree corresponding to each leakage cause; analyzing changes of the residual current before each leakage according to the historical leakage data to obtain residual current change characteristics corresponding to each leakage cause; determining a target leakage cause corresponding to the current time period according to the residual current change characteristics corresponding to each leakage cause, and determining a data weight corresponding to the current time period according to the importance degree corresponding to the target leakage cause; and performing leakage prediction on the electrical device according to the data weight corresponding to the current time period and the input current and the residual current in the current time period to obtain a leakage prediction result, so as to monitor the leakage of the electrical device.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electric variable measurement, and in particular to a leakage monitoring method of an electrical device. BACKGROUND

[0002] Leakage of an electrical device refers to a phenomenon that, under normal operation or fault condition, current leaks to the device shell, ground or other conductive objects through an insulation damaged part or other abnormal path, and the reasons for leakage usually include insulation aging, mechanical damage, humid environment, etc. Leakage of an electrical device is likely to cause electric shock danger, equipment damage and even fire hazards. In order to prevent electric shock accidents and ensure personal and equipment safety, it is necessary to accurately monitor the electrical device, discover leakage faults in time and take measures.

[0003] A commonly used method for monitoring leakage of an electrical device is to determine whether leakage occurs based on the size of residual current in a circuit, compare the residual current with a preset threshold, and consider that leakage occurs and trigger a protection action when the residual current exceeds the set threshold. This method can only detect problems when obvious leakage occurs, and cannot prevent potential faults such as aging and insulation performance degradation of the device that lead to leakage, so it cannot discover device hazards in time, resulting in insufficient accuracy of leakage monitoring. It cannot issue an early warning when the problem occurs early, which is not conducive to taking measures in advance to prevent leakage accidents, and thus leads to insufficient safety of the electrical device in use.

[0004] Therefore, how to improve the accuracy of leakage monitoring and the safety of the electrical device in use is a problem to be solved at present. SUMMARY

[0005] In order to solve the technical problem of how to improve the accuracy of leakage monitoring and the safety of the electrical device in use, the purpose of the present application is to provide a leakage monitoring method of an electrical device, and the technical solution adopted is as follows:

[0006] The present application provides a leakage monitoring method of an electrical device, which comprises:

[0007] Obtaining input current and residual current of the electrical device in a current time period and historical leakage data;

[0008] According to the historical leakage data, analyzing the leakage reasons of the electrical device to obtain historical leakage characteristics and an importance degree corresponding to each leakage reason;

[0009] According to the historical leakage data, analyzing the change of the residual current before each leakage to obtain a residual current change characteristic corresponding to each leakage reason;

[0010] determine a target leakage reason corresponding to the current time period according to the residual current change characteristic corresponding to each leakage reason, and determine a data weight corresponding to the current time period according to an importance degree corresponding to the target leakage reason;

[0011] According to the data weight corresponding to the current time period, and the input current and the residual current in the current time period, leakage prediction is performed on the electrical equipment to obtain a leakage prediction result, so as to realize leakage monitoring of the electrical equipment.

[0012] In some embodiments, the input current and the residual current of the electrical equipment in the current time period are obtained, including:

[0013] The input current requirement, the measurement accuracy requirement, the application scenario information and the protection requirement corresponding to the electrical equipment are obtained.

[0014] According to the input current requirement and the measurement accuracy requirement, a target current sensor is determined, and the input current of the electrical equipment in the current time period is obtained through the target current sensor, wherein the measurement probe of the target current sensor is perpendicular to the current line of the input current of the electrical equipment.

[0015] According to the application scenario information and the protection requirement, a target electronic leakage protection device is determined, the input power line of the electrical equipment is connected to the input end of the target electronic leakage protection device, and the output end of the target electronic leakage protection device is linked to the input end of the electrical equipment, so as to obtain the residual current of the electrical equipment in the current time period.

[0016] In some embodiments, the leakage reason of the electrical equipment is analyzed according to the historical leakage data to obtain the historical leakage characteristic and the importance degree corresponding to each leakage reason, including:

[0017] According to the leakage information and the leakage reason corresponding to a plurality of leakage events in the historical leakage data, the leakage intensity of the electrical equipment is analyzed, and according to the analysis result of the leakage intensity, the damage degree of the electrical equipment is determined, and the damage degree is taken as the historical leakage characteristic.

[0018] According to the leakage event corresponding to each leakage reason and the damage degree of the electrical equipment, the importance of each leakage reason is analyzed to obtain the importance degree corresponding to each leakage reason.

[0019] In some embodiments, according to the leakage information and the leakage reason corresponding to a plurality of leakage events in the historical leakage data, the leakage intensity of the electrical equipment is analyzed, and according to the analysis result of the leakage intensity, the damage degree of the electrical equipment is determined, including:

[0020] According to the historical leakage data, the number of the plurality of leakage events and the leakage residual current corresponding to each leakage event, the leakage time interval between adjacent leakage events are determined;

[0021] According to the number of the plurality of leakage events and the leakage residual current corresponding to each leakage event, a first residual current sequence is established;

[0022] According to the number of the plurality of leakage events and the leakage time interval between adjacent leakage events, a first time interval sequence is established;

[0023] The first residual current sequence and the first time interval sequence are respectively subjected to difference calculation to obtain a first residual current difference sequence and a first time interval difference sequence;

[0024] According to the mean value of the first residual current difference sequence and the mean value of the first time interval difference sequence, the leakage intensity of the electrical equipment is determined;

[0025] According to the number of the leakage causes and the leakage intensity of the electrical equipment, the damage degree of the electrical equipment is determined.

[0026] In some embodiments, the importance analysis of each leakage cause according to the leakage event corresponding to each leakage cause and the damage degree of the electrical equipment is performed to obtain the importance degree corresponding to each leakage cause, including:

[0027] According to the leakage cause, the leakage event is classified to obtain the number of times of occurrence of the leakage event corresponding to each leakage cause and the occurrence time and duration of each leakage event;

[0028] According to the occurrence time and duration of each leakage event, the time interval between the leakage events corresponding to each leakage cause is determined, and according to the time interval between the leakage events corresponding to each leakage cause, the maximum time interval between adjacent leakage events corresponding to each leakage cause is determined;

[0029] In combination with the damage degree of the electrical equipment, the number of times of occurrence of the leakage event corresponding to each leakage cause and the maximum time interval between adjacent leakage events corresponding to each leakage cause, the importance degree corresponding to each leakage cause is determined.

[0030] In some embodiments, the analysis of the change of residual current before each leakage according to the historical leakage data is performed to obtain the residual current change feature corresponding to each leakage cause, including:

[0031] determine a reference current change amplitude of each of the leakage causes according to the occurrence time and the duration of each of the leakage events;

[0032] analyze the current change over time according to a second residual current sequence before each of the leakage events, to obtain a current change rate of each of the leakage events, cluster the current change rate of each of the leakage events, and determine a reference current change rate of each of the leakage causes according to the clustering result;

[0033] correct the current change rate of each of the leakage events according to the number of leakage events of each of the leakage causes, and update the reference current change rate of each of the leakage causes according to the corrected current change rate of each of the leakage events, to obtain a new reference current change rate of each of the leakage causes;

[0034] determine the residual current change characteristic corresponding to each of the leakage causes in combination with the new reference current change rate of each of the leakage causes and the reference current change amplitude of each of the leakage causes.

[0035] In some embodiments, the determination of the reference current change amplitude of each of the leakage causes according to the occurrence time and the duration of each of the leakage events comprises:

[0036] determine a minimum time interval according to the occurrence time and the duration of each of the leakage events, and take the minimum time interval as a reference time interval;

[0037] for the leakage events of each of the leakage causes, obtain a plurality of second residual current sequences corresponding to each of the leakage causes according to a second residual current sequence within the reference time interval before each of the leakage events;

[0038] take the difference between the maximum value and the minimum value in each second residual current sequence as the current change amplitude of the leakage event;

[0039] take the maximum current change amplitude in the plurality of second residual current sequences as the reference current change amplitude of each of the leakage causes.

[0040] In some embodiments, the determination of the target leakage cause corresponding to the current time period according to the residual current change characteristic corresponding to each of the leakage causes, and the determination of the data weight corresponding to the current time period according to the importance degree corresponding to the target leakage cause, comprises:

[0041] obtain a third residual current sequence of the electrical equipment at an interval of the reference time interval before the current time period;

[0042] According to the third residual current sequence and a preset residual current threshold, a residual current difference value is determined, and a change of the residual current of the electrical equipment in the current time period is fitted, and a residual current change trend is determined according to a fitting result;

[0043] According to the third residual current sequence, a change of the current over time is analyzed to obtain a current change rate of the electrical equipment in the current time period, and in combination with a current change amplitude corresponding to the third residual current sequence, a residual current change characteristic of the current time period is obtained;

[0044] The residual current change characteristic of the current time period is compared with the residual current change characteristic corresponding to each leakage reason to obtain a plurality of characteristic differences;

[0045] The plurality of characteristic differences are compared with a preset difference threshold, and a target leakage reason corresponding to the current time period is determined according to a comparison result, and an importance degree of the target leakage reason is determined;

[0046] In combination with the residual current difference value, the residual current change trend and the importance degree of the target leakage reason, a data weight corresponding to the current time period is determined.

[0047] In some embodiments, the comparison of the plurality of characteristic differences with the preset difference threshold and the determination of the target leakage reason corresponding to the current time period and the importance degree of the target leakage reason according to the comparison result include:

[0048] When the comparison result is a plurality of target leakage reasons corresponding to the current time period, the importance degree of the target leakage reason is obtained based on the characteristic difference and the importance degree corresponding to each leakage reason.

[0049] In some embodiments, the leakage prediction of the electrical equipment according to the data weight corresponding to the current time period and the input current and the residual current in the current time period to obtain a leakage prediction result, so as to realize the leakage monitoring of the electrical equipment includes:

[0050] The input current and the residual current in the current time period and the data weight corresponding to the current time period are input into a pre-trained leakage prediction model to obtain a predicted residual current value;

[0051] When the predicted residual current value is greater than a preset residual current threshold, it is determined that a leakage risk occurs.

[0052] The present application has the following beneficial effects:

[0053] First, the input current and residual current of the electrical equipment in the current time period and historical leakage data are obtained; then, the leakage causes of the electrical equipment are analyzed according to the historical leakage data, and the historical leakage characteristics and the importance degree corresponding to each leakage cause are obtained; then, the change of the residual current before each leakage is analyzed according to the historical leakage data, and the residual current change characteristics corresponding to each leakage cause are obtained; then, the target leakage cause corresponding to the current time period is determined according to the residual current change characteristics corresponding to each leakage cause, and the data weight corresponding to the current time period is determined according to the importance degree corresponding to the target leakage cause; finally, the leakage of the electrical equipment is predicted according to the data weight corresponding to the current time period and the input current and residual current in the current time period, and a leakage prediction result is obtained, so as to realize the leakage monitoring of the electrical equipment. In this application, by obtaining the current input current and residual current data, the current running current state of the electrical equipment can be mastered in real time, and instant data support is provided for subsequent analysis. At the same time, the historical leakage data is obtained, and the past leakage conditions are analyzed, and reference basis is provided for predicting future leakage from the historical experience. With comprehensive historical and current data, the analysis of the leakage condition of the equipment is more comprehensive, and the leakage monitoring accuracy is improved. The leakage information of different times recorded in the historical leakage data can help analyze the rules of leakage occurrence, and is helpful to discover potential leakage risks in advance and ensure the safety of the electrical equipment. The leakage cause analysis of the historical leakage data can deeply understand various factors leading to the leakage of the equipment. By obtaining the historical leakage characteristics, the overall characteristics of the past leakage of the equipment can be clearly grasped, such as leakage intensity and leakage frequency. Determining the importance degree corresponding to each leakage cause can help to determine which leakage causes have greater impact on the equipment, so as to focus on these key factors in the monitoring process. The residual current of different leakage causes often has different change characteristics before occurrence, and the residual current change characteristics corresponding to each leakage cause are summarized by analyzing the residual current change before each leakage in the historical leakage data. In this way, in actual monitoring, when similar change characteristics are observed in the residual current, the possible leakage cause can be more accurately judged, the leakage monitoring accuracy is improved, potential leakage risks are discovered in advance according to these characteristics, timely measures are taken, and the safety of the electrical equipment is ensured. According to the summarized residual current change characteristics corresponding to each leakage cause, the current possible target leakage cause is determined by comparing with the residual current change in the current time period.The data weight is determined according to the importance degree of the target leakage cause, so that when leakage is predicted, higher weight is given to factors that may cause serious leakage risk, and more attention is paid to the influence of these factors on leakage prediction, the accuracy of prediction is improved, and the leakage risk is more accurately judged, the leakage monitoring accuracy is improved, and the safety of the electrical equipment is improved. The data weight is combined with the current input current and the residual current to predict leakage, and the influence degree of different factors on leakage is fully considered, and the leakage prediction result obtained by this method is more scientific and accurate, and the potential leakage risk can be found in advance. When the prediction result shows that leakage may occur, the power supply can be cut off in advance or the equipment can be checked and repaired, so as to avoid leakage accidents and improve the leakage monitoring accuracy and the safety of the electrical equipment. BRIEF DESCRIPTION OF DRAWINGS

[0054] In order to more clearly illustrate the technical solutions and advantages of the embodiments of the present application or the prior art, the drawings needed in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0055] Figure 1 An implementation environment schematic diagram of a leakage monitoring method of an electrical equipment provided by an embodiment of the present application;

[0056] Figure 2 A flowchart schematic diagram of a leakage monitoring method of an electrical equipment provided by an embodiment of the present application;

[0057] Figure 3 A structure schematic diagram of a leakage monitoring device of an electrical equipment provided by an embodiment of the present application;

[0058] Figure 4 A structure schematic diagram of a computer system suitable for an electronic device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0059] In order to further illustrate the technical means and effects adopted by the present application to achieve the predetermined object, the specific implementation, structure, features and effects of the leakage monitoring method of an electrical equipment according to the present application are described in detail as follows. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures or characteristics in one or more embodiments can be combined in any suitable form.

[0060] It should be noted that the terms "first", "second", and the like in the description of the application and the above drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, device, product or apparatus including a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or apparatus.

[0061] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the application belongs.

[0062] The specific scheme of the electric equipment leakage monitoring method provided by the application will be described in detail below with reference to the accompanying drawings.

[0063] Please refer to Figure 1 , Figure 1 The implementation environment schematic diagram of the electric equipment leakage monitoring method provided by an embodiment of the application. As Figure 1 shown, the implementation environment includes a leakage monitoring terminal 101 and an electric equipment 102. The leakage monitoring terminal 101 can be a terminal device installed with a leakage monitoring platform, including but not limited to a mobile device with local computing capability, a notebook computer, a tablet computer, a palm computer, a PAD, a desktop computer, etc.; the leakage monitoring platform can be implemented in the form of a target client, which can be a video client, an instant messaging client, a browser client, etc. supporting leakage monitoring; the leakage monitoring terminal 101 can communicate with the electric equipment 102 through a network, which can include but is not limited to a wired network, a wireless network, wherein the wired network includes a local area network, a metropolitan area network and a wide area network, and the wireless network includes Bluetooth, WIFI and other wireless communication networks. The leakage monitoring terminal 101 can include but is not limited to a human-computer interaction screen, a processor and a memory. The processor can be used to respond to human-computer interaction operations, execute corresponding operations, or generate corresponding instructions.

[0064] As an optional way, the leakage monitoring terminal 101 can be a computer, through which the input current and residual current of the electric equipment 102 in the current time period and the historical leakage data can be obtained in real time.

[0065] As an optional mode, the leakage monitoring terminal 101 can be a server, which can be a single server, a server cluster composed of multiple servers, or a cloud server. The above is only an example, and the present embodiment does not make any limitation on this.

[0066] As an optional mode, the leakage monitoring terminal 101 can be a server, which can be a single server, a server cluster composed of multiple servers, or a cloud server. The above is only an example, and the present embodiment does not make any limitation on this.

[0067] As an optional mode, the leakage monitoring terminal 101 can be a server, which can be a single server, a server cluster composed of multiple servers, or a cloud server. The above is only an example, and the present embodiment does not make any limitation on this.

[0068] As an optional mode, the leakage monitoring terminal 101 can be a server, which can be a single server, a server cluster composed of multiple servers, or a cloud server. The above is only an example, and the present embodiment does not make any limitation on this.

[0069] As an optional mode, the leakage monitoring terminal 101 can be a server, which can be a single server, a server cluster composed of multiple servers, or a cloud server. The above is only an example, and the present embodiment does not make any limitation on this.

[0070] As an optional mode, the leakage monitoring terminal 101 can be a server, which can be a single server, a server cluster composed of multiple servers, or a cloud server. The above is only an example, and the present embodiment does not make any limitation on this.

[0071] As an optional mode, the leakage monitoring terminal 101 can be a server, which can be a single server, a server cluster composed of multiple servers, or a cloud server. The above is only an example, and the present embodiment does not make any limitation on this.

[0072] As an optional mode, the leakage monitoring terminal 101 can be a server, which can be a single server, a server cluster composed of multiple servers, or a cloud server. The above is only an example, and the present embodiment does not make any limitation on this.

[0073] As an optional mode, the leakage monitoring terminal 101 can be a server, which can be a single server, a server cluster composed of multiple servers, or a cloud server. The above is only an example, and the present embodiment does not make any limitation on this.

[0074] As an optional mode, the leakage monitoring terminal 101 can be a server, which can be a single server, a server cluster composed of multiple servers, or a cloud server. The above is only an example, and the present embodiment does not make any limitation on this. Figure 2 , Figure 2 As an optional mode, the leakage monitoring terminal 101 can be a server, which can be a single server, a server cluster composed of multiple servers, or a cloud server. The above is only an example, and the present embodiment does not make any limitation on this. Figure 1The illustrated implementation environment. It should be understood that the method can also be applied to other exemplary implementation environments and specifically executed by devices in other implementation environments, and the present embodiment does not limit the implementation environment to which the method is applied.

[0075] As shown in an exemplary embodiment, the leakage monitoring method of the electrical equipment at least includes steps S210 to S230, which are described in detail as follows: Figure 2

[0076] In step S210, the input current and residual current of the electrical equipment in the current time period and the historical leakage data are obtained.

[0077] Among them, the electrical equipment refers to various devices used for power generation, power transmission, power transformation, power distribution and power consumption in the power system, such as transformers, motors, etc., which can refer to transformers in industrial production, and are the objects of the present leakage monitoring method. Among them, the current time period refers to a specific time range being monitored and analyzed, which can be used to obtain the input current, residual current and other data of the transformer in this time period, so as to analyze the leakage condition in combination with the historical data. Among them, the input current refers to the current flowing into the electrical equipment, which provides energy for the operation of the equipment. The input current of the transformer can be collected by selecting a suitable current sensor, such as a Hall effect current sensor, to understand the working current state of the transformer. Among them, the residual current refers to the additional current that should be zero when the working current vector through the electrical equipment is zero, but appears when leakage occurs. The residual current of the transformer can be collected by using an electronic leakage protection device to determine whether leakage occurs and analyze the leakage condition. Among them, the historical leakage data refers to the data record generated when the electrical equipment leaks in the past, including the number of times of leakage, the size of residual current of each leakage, the cause of leakage and other information. By analyzing the historical leakage data, the leakage characteristics and reasons of the transformer in the past can be mastered to provide a basis for predicting future leakage.

[0078] In step S220, the leakage reason of the electrical equipment is analyzed according to the historical leakage data, and the historical leakage characteristics and the importance degree corresponding to each leakage reason are obtained.

[0079] Among them, the leakage reason is the factor that causes the electrical equipment to leak, which is commonly known as insulation aging, external damage, environmental factors, etc. The leakage reason of the transformer can be analyzed to determine the importance of different reasons for targeted monitoring. Among them, the historical leakage characteristics are the overall characteristics of the electrical equipment leakage based on the analysis of the historical leakage data, such as leakage intensity and leakage frequency. The historical leakage characteristics of the transformer can be obtained by analyzing the historical leakage times and residual current changes, reflecting its past leakage condition.

[0080] ​The importance degree of each leakage cause is calculated according to the number of times of leakage caused by different leakage causes, time intervals and other factors in historical leakage data, and is used to measure the size of the influence of each leakage cause on the leakage of the equipment. The leakage cause with high importance degree needs to be focused on during monitoring.

[0081] In step S230, the change of residual current before each leakage is analyzed according to the historical leakage data, and the residual current change characteristics corresponding to each leakage cause are obtained.

[0082] The change of residual current before leakage refers to the change of residual current in terms of value, change rate and the like before each leakage event occurs. By analyzing the change, the residual current change rule corresponding to different leakage causes can be summarized. The residual current change characteristics corresponding to each leakage cause are reference characteristics obtained by analyzing the residual current change before leakage for different leakage causes, such as current change rate, amplitude change, etc., which are used to compare with the current residual current change to determine the current possible leakage cause.

[0083] In step S240, the target leakage cause corresponding to the current time period is determined according to the residual current change characteristics corresponding to each leakage cause, and the data weight corresponding to the current time period is determined according to the importance degree of the target leakage cause.

[0084] The target leakage cause corresponding to the current time period is determined according to the comparison between the residual current change characteristics of the current time period and the residual current change characteristics corresponding to each leakage cause, and is the cause most likely to cause leakage at present. After the target leakage cause is determined, measures can be taken accordingly. The data weight corresponding to the current time period is determined in combination with the difference between the current residual current and the preset threshold, the residual current change trend and the importance degree of the target leakage cause, and is used to reflect the importance of different factors in leakage prediction. The higher the data weight, the greater the influence of the corresponding factor in leakage prediction.

[0085] In step S250, the leakage of the electrical equipment is predicted according to the data weight corresponding to the current time period and the input current and residual current in the current time period, and a leakage prediction result is obtained to realize the leakage monitoring of the electrical equipment.

[0086] The leakage prediction refers to predicting whether the electrical equipment will have leakage in the future and the possibility of leakage according to the data and historical data of the current time period and other information, and the leakage prediction result is the conclusion of the leakage prediction, such as the predicted residual current value, and whether there is a leakage risk according to the value, and when the predicted residual current value exceeds the preset threshold, it indicates that the transformer has a leakage risk.

[0087] For example, taking a transformer in a factory as an example, the current time period is set to the last one hour. The input current of the transformer in this hour is collected by a suitable current sensor, and the residual current is obtained by using an electronic leakage protection device. The historical leakage data of the transformer in the past year is collected, including a total of 5 times of leakage, of which 3 times are due to insulation aging and 2 times are due to external damage. By analyzing these historical leakage data, it is concluded that the leakage intensity caused by insulation aging is high, and the historical leakage characteristics show that the number of leakage is gradually increasing. It is calculated that the importance of the leakage reason of insulation aging is high. By analyzing the change of residual current before each leakage, it is concluded that the change of residual current before insulation aging is relatively slow. By comparing the change of residual current in the current one hour with the change characteristics of the residual current corresponding to each leakage reason, it is found that it is similar to the characteristics of insulation aging, and it is determined that the target leakage reason corresponding to the current time period is insulation aging, and then the data weight corresponding to the current time period is determined. Finally, the data weight, the input current and the residual current in the current one hour are input into the model for leakage prediction to obtain the predicted residual current value and determine whether there is a leakage risk.

[0088] In an embodiment of the present application, the input current and the residual current of the electrical equipment in the current time period are obtained, including:

[0089] Obtaining the input current requirement, the measurement accuracy requirement, the application scenario information and the protection requirement corresponding to the electrical equipment;

[0090] According to the input current requirement and the measurement accuracy requirement, a target current sensor is determined, and the input current of the electrical equipment in the current time period is obtained through the target current sensor, wherein the measurement probe of the target current sensor is perpendicular to the current line of the input current of the electrical equipment;

[0091] According to the application scenario information and the protection requirement, a target electronic leakage protection device is determined, the input power line of the electrical equipment is connected to the input end of the target electronic leakage protection device, and the output end of the target electronic leakage protection device is linked to the input end of the electrical equipment, so as to obtain the residual current of the electrical equipment in the current time period.

[0092] The input current requirement refers to the relevant parameter requirements of the input current required for the normal operation of the electrical equipment, such as the size range of the current, the type of the current (AC or DC), and the like. For a transformer, the input current requirement determines the selection of a current sensor of which specification to accurately collect the input current, so as to ensure that the collected data can truly reflect the running state of the transformer.

[0093] The measurement accuracy requirement is a regulation on the error range allowed when collecting the current data of the electrical equipment. Different electrical equipment or application scenarios have different requirements for measurement accuracy, and higher measurement accuracy can make the collected data more accurate, thereby providing a reliable basis for subsequent leakage monitoring and analysis. The measurement accuracy requirement affects the selection of the current sensor, so as to meet the demand for accurate measurement of the input current of the transformer.

[0094] The application scenario information describes the environment and conditions in which the electrical equipment is actually used, such as industrial environment, home environment, and the temperature, humidity, electromagnetic interference, and the like of the equipment running. Different application scenarios will have different effects on the leakage monitoring of the electrical equipment, and will also affect the selection of the monitoring equipment. The transformer is in an industrial production scenario, which will affect the selection of the residual current collection equipment.

[0095] The protection requirement refers to the relevant requirements of the protection measures that need to be taken to ensure the safe operation of the electrical equipment in the event of leakage and the like, such as the regulations on the leakage operating current, the operating time, and the like. In the present application, the protection requirement determines how to select a suitable electronic leakage protection equipment to effectively monitor the residual current of the transformer, thereby ensuring the safety of the equipment and personnel.

[0096] The target current sensor is a device selected according to the input current requirement and the measurement accuracy requirement of the electrical equipment, and is used to collect the input current. It can convert the current signal into a signal form that is convenient for measurement and processing. In the present application, a Hall effect current sensor is selected as the target current sensor according to the input current characteristics and the measurement accuracy requirement of the transformer, and it is required that the measurement probe is perpendicular to the current line to ensure the measurement accuracy.

[0097] The target electronic leakage protection equipment is determined according to the application scenario information and the protection requirement of the electrical equipment, and is used to collect the residual current and perform a protection action when leakage is detected. It has specific parameters such as rated current, leakage operating current, and operating time, and can select an electronic leakage protection equipment with appropriate parameters to accurately collect the residual current according to the application scenario and the protection requirement of the transformer.

[0098] For example, in industrial production, transformers are mainly used to provide appropriate voltage levels for various electrical equipment in the factory, such as providing high voltage for large motors and providing low voltage for lighting equipment and small appliances. During the operation of the transformer, there are many reasons for the occurrence of leakage, such as insulation aging, external damage, environmental factors, improper maintenance, overvoltage and overload, etc. The severity of leakage caused by different reasons may also have certain differences. In order to predict future leakage in advance according to the historical leakage of the transformer during operation, the current, residual current and leakage of the transformer during historical operation and the current period of time need to be obtained. First, select a suitable current sensor, such as a Hall effect current sensor, according to the size of the transformer input current and the measurement accuracy requirement, select a sensor with appropriate range and accuracy, install it near the transformer input line, ensure that the sensor measurement probe is perpendicular to the current line to obtain accurate measurement results, and connect the sensor output signal to the measuring instrument or data acquisition system. According to the output characteristics of the sensor, select the appropriate measuring instrument or set the parameters of the data acquisition system to correctly display and record the current value; then, select an electronic leakage protection device to collect the residual current, according to the application scene and protection requirements of the transformer, select an electronic leakage protection device with appropriate rated current, leakage action current and action time, install the device near the transformer power supply side, connect the transformer input power line to the input end of the leakage protection device, ensure that the wiring is firm, correct and meets the electrical safety specifications; At the same time, connect the output end of the leakage protection device to the input terminal of the transformer. The input current and residual current of the transformer are obtained by the above method.

[0099] In this embodiment, by obtaining input current requirements, measurement accuracy requirements and other information, the appropriate monitoring device is selected, which can ensure that the collected input current and residual current data are accurate and reliable, and provide a solid data foundation for subsequent leakage monitoring analysis, thereby improving the accuracy of leakage monitoring. According to the application scene information, the appropriate device is selected, so that the monitoring device can better adapt to the actual environment of the electrical equipment, ensure stable operation of the device, improve the stability and reliability of data acquisition, and help more accurately monitor the leakage. According to the protection requirements, the target electronic leakage protection device is selected, which can not only accurately collect the residual current, but also take protective action in time when leakage occurs, protect the safety of electrical equipment and personnel, and improve the safety of electrical equipment use.

[0100] In an embodiment of the present application, the historical leakage data is analyzed to analyze the leakage reasons of the electrical equipment, and the historical leakage characteristics and the importance degree corresponding to each leakage reason are obtained, comprising:

[0101] According to the leakage information and the leakage reason corresponding to a plurality of leakage events in the historical leakage data, the leakage intensity of the electrical equipment is analyzed, and according to the analysis result of the leakage intensity, the damage degree of the electrical equipment is determined as the historical leakage feature.

[0102] According to the leakage event corresponding to each leakage reason and the damage degree of the electrical equipment, the importance of each leakage reason is analyzed to obtain the importance degree corresponding to each leakage reason.

[0103] Wherein, when the transformer is in normal operation, the three-phase current is balanced, and the value of the residual current is usually in a low range. When the transformer leaks, a part of the current will flow to the ground or other unintended loops through the leakage path, and the residual current transformer will detect an additional current, that is, the residual current. The more serious the leakage is, the larger the residual current is, which will generally be significantly higher than the threshold during normal operation. There can be many reasons for transformer leakage. Each time leakage occurs, the length of time is different. It may be continuous leakage or intermittent leakage, and the leakage current caused by different leakage reasons is different, that is, the leakage intensity is different. In order to predict the possibility of future leakage in advance and give an early warning, it is necessary to analyze the historical leakage situation first.

[0104] Wherein, the leakage event refers to the specific case of actual leakage of the electrical equipment. Each leakage occurrence constitutes a leakage event, and these events contain various information related to leakage and are the basic unit for analyzing leakage.

[0105] Wherein, the leakage information refers to the relevant data and situation description accompanied by the leakage event, such as the time of leakage, the size of the residual current during leakage, the duration of leakage, etc. These information is crucial for a comprehensive understanding of the leakage event and further analysis of the leakage reason and characteristics. Leakage information can be obtained from historical leakage data for in-depth analysis of transformer leakage.

[0106] Wherein, the leakage intensity is a comprehensive indicator for measuring the severity of electrical equipment leakage, which is calculated by analyzing some key parameters in the leakage event, such as the change of residual current, the frequency of leakage occurrence, etc. Leakage intensity reflects the severity of the impact of leakage on electrical equipment. In this embodiment, leakage intensity is used to evaluate the severity of transformer leakage, which is an important basis for determining the damage degree of the transformer.

[0107] The damage degree of the electrical equipment is a quantitative description of the degree of damage of the electrical equipment due to the electric leakage based on the electric leakage intensity and other factors. The higher the damage degree is, the greater the damage of the electrical equipment due to the electric leakage is, and the higher the risk of failure in subsequent operation is. In the present application, the damage degree of the transformer is taken as an embodiment of the historical electric leakage feature, which provides an important reference for judging the operation condition of the transformer and predicting future electric leakage.

[0108] In the present embodiment, the electric leakage intensity is obtained through the analysis of the electric leakage events and the electric leakage information, and the damage degree of the electrical equipment is determined, which can quantify the damage of the electrical equipment due to the electric leakage, make the understanding of the equipment condition more clear and accurate, and provide more targeted data support for the electric leakage monitoring, thereby improving the accuracy of the electric leakage monitoring. The importance of each electric leakage cause can be analyzed based on the damage degree of the electrical equipment and the electric leakage events corresponding to each electric leakage cause, which can determine the influence of different electric leakage causes on the equipment, and the important electric leakage causes can be focused on in subsequent electric leakage monitoring, thereby improving the pertinence and effectiveness of the electric leakage monitoring, and further improving the accuracy of the electric leakage monitoring. The damage degree is taken as a historical electric leakage feature, which provides an intuitive and key reference index for evaluating the historical electric leakage condition of the electrical equipment, and helps to better predict the future electric leakage trend, take preventive measures in advance, and ensure the safe use of the electrical equipment, thereby improving the safety of the use of the electrical equipment.

[0109] In an embodiment of the present application, the electric leakage intensity of the electrical equipment is analyzed according to the electric leakage information and the electric leakage causes corresponding to a plurality of electric leakage events in the historical electric leakage data, and the damage degree of the electrical equipment is determined according to the analysis result of the electric leakage intensity, which comprises:

[0110] According to the historical electric leakage data, the number of the plurality of electric leakage events, the electric leakage residual current corresponding to each electric leakage event, and the electric leakage time interval between adjacent electric leakage events are determined;

[0111] According to the number of the plurality of electric leakage events and the electric leakage residual current corresponding to each electric leakage event, a first residual current sequence is established;

[0112] According to the number of the plurality of electric leakage events and the electric leakage time interval between adjacent electric leakage events, a first time interval sequence is established;

[0113] The first residual current sequence and the first time interval sequence are respectively subjected to difference calculation to obtain a first residual current difference sequence and a first time interval difference sequence;

[0114] The electric leakage intensity of the electrical equipment is determined according to the mean value of the first residual current difference sequence and the mean value of the first time interval difference sequence;

[0115] According to the number of the leakage causes and the leakage intensity of the electrical equipment, a damage degree of the electrical equipment is determined.

[0116] The leakage residual current corresponding to each leakage event refers to a residual current value measured by a relevant detection device when the electrical equipment leaks each time. This value can intuitively reflect the degree of current leakage each time, and is one of important data for analyzing the leakage intensity. In the transformer leakage monitoring scenario, the residual current detected each time the transformer leaks is the content referred to by this feature.

[0117] The leakage time interval between adjacent leakage events refers to the time span of adjacent two leakage events of the electrical equipment. It reflects the frequency of leakage occurrence, and is of great significance for evaluating the running stability and leakage development trend of the electrical equipment. In the example of the transformer, it is the time length between two consecutive leakage events.

[0118] According to the number of the plurality of leakage events and the leakage residual current corresponding to each leakage event, a first residual current sequence is established. The first residual current sequence is a sequence formed by arranging the leakage residual current corresponding to each leakage event in the plurality of leakage events in a certain order. By constructing this sequence, the change rule of the residual current with the leakage event can be observed as a whole, and a data basis is provided for subsequent analysis of the leakage intensity. For example, arranging the residual current value corresponding to each leakage event in chronological order into a sequence is the first residual current sequence.

[0119] According to the number of the plurality of leakage events and the leakage time interval between adjacent leakage events, a first time interval sequence is established. The first time interval sequence is a sequence formed by arranging the time interval between adjacent leakage events in order according to the occurrence of the plurality of leakage events. The sequence is used to analyze the time interval change trend of the leakage event, and assist in judging the frequency and development trend of the leakage. For example, arranging the time interval between adjacent two leakage events in order forms the first time interval sequence.

[0120] The difference calculation is a mathematical calculation method for analyzing the difference between adjacent data in a sequence. In this application, by performing difference calculation on the first residual current sequence and the first time interval sequence, the change amount of adjacent data can be obtained, and the change trend of the residual current and the leakage time interval with the leakage event can be analyzed, which is helpful to more accurately determine the leakage intensity.

[0121] Wherein, the difference sequence is a new sequence obtained by difference calculation on the original sequence. In the present application, the first residual current sequence is subjected to difference calculation to obtain the first residual current difference sequence, and the first time interval sequence is subjected to difference calculation to obtain the first time interval difference sequence. These difference sequences reflect the change of adjacent data in the original sequence, and are the key data for further determining the leakage intensity.

[0122] For example, the number of leakage of the transformer in the historical time is counted, and the size of the residual current at each leakage is obtained to obtain a residual current sequence. The residual current sequence is subjected to first-order difference to obtain a corresponding first-order difference sequence. The mean value of all values in the first-order difference sequence is calculated and denoted as q1. The greater the value of q1, the greater the residual current at each leakage increases with time. The time interval between adjacent leakage events is counted to obtain a time interval sequence. Similarly, the first-order difference sequence of the time interval sequence is obtained, and the mean value of all values in the first-order difference sequence is calculated and denoted as q2. The smaller the value of q2, the smaller the time interval between leakage events, and the more frequent the leakage. The leakage intensity of the transformer in the historical time can be represented as:

[0123]

[0124] Wherein, m represents all the leakage times in the history.

[0125] Among all the different leakage events in the history, there may be multiple different reasons, and the reasons for each leakage event are not completely the same. Therefore, the damage degree of the transformer can be represented as:

[0126]

[0127] Wherein, Q represents the leakage intensity in the historical time, and y represents the number of leakage reasons. The more reasons leading to leakage, the greater the leakage intensity, and the greater the damage degree L of the transformer. Thus, the damage degree of the transformer is obtained. The more serious the damage, the more attention needs to be paid to the safety hazards of the transformer caused by leakage in subsequent operation. It should be noted that, in order to ensure that the calculation result is meaningful, when performing fractional operation, the present application adds a parameter adjustment factor greater than 0 to the denominator to prevent the denominator from being 0. The value of the parameter adjustment factor is set by the implementer according to the actual situation, and the present application is set to 0.1.

[0128] In this embodiment, by determining the leakage residual current corresponding to each leakage event and the leakage time interval between adjacent leakage events, the first residual current sequence and the first time interval sequence are established, which can systematically organize the leakage-related data, provide an ordered data set for subsequent in-depth analysis of the leakage intensity, and make the analysis process more logical and accurate. The difference sequence obtained by difference calculation of the two sequences can highlight the change trend of the leakage residual current and the leakage time interval, which helps to accurately capture the dynamic changes of the leakage situation, thereby more accurately determining the leakage intensity and improving the accuracy of the leakage situation analysis, providing a reliable basis for evaluating the damage degree of the electrical equipment. According to the leakage intensity and the number of leakage causes, the damage degree of the electrical equipment is determined, which realizes the quantitative evaluation of the damage of the electrical equipment due to leakage, provides key indicators for a comprehensive understanding of the operation status of the electrical equipment, helps to discover potential risks in advance, and takes timely measures to ensure the safe operation of the electrical equipment, thereby improving the safety of the electrical equipment.

[0129] In an embodiment of the present application, the importance analysis of each leakage cause is performed according to the leakage event corresponding to each leakage cause and the damage degree of the electrical equipment, and the importance degree corresponding to each leakage cause is obtained, including:

[0130] According to the leakage cause, the leakage events are classified to obtain the number of leakage events corresponding to each leakage cause, and the occurrence time and duration of each leakage event;

[0131] According to the occurrence time and duration of each leakage event, the time interval between the leakage events corresponding to each leakage cause is determined, and the maximum time interval between adjacent leakage events corresponding to each leakage cause is determined according to the time interval between the leakage events corresponding to each leakage cause;

[0132] The importance degree corresponding to each leakage cause is determined in combination with the damage degree of the electrical equipment, the number of leakage events corresponding to each leakage cause, and the maximum time interval between adjacent leakage events corresponding to each leakage cause.

[0133] According to the leakage cause, the leakage events are classified, which means that according to different leakage causes, numerous leakage events are classified. The purpose of this is to analyze each leakage cause respectively, so as to clearly understand the specific situation of each cause causing leakage. For example, in the electrical equipment leakage monitoring, the leakage causes may include insulation aging, external damage, environmental factors, etc. Grouping all leakage events according to these causes makes the leakage events in the same group have the same inducing factors, which facilitates subsequent statistics and analysis of the number of leakage events corresponding to each leakage cause, the occurrence time, etc.

[0134] According to the occurrence time and duration of each electric leakage event, the time interval between the electric leakage events corresponding to each electric leakage cause is determined, which is calculated by using the specific time point of the occurrence of each electric leakage event and the duration of the event, to calculate the time span between adjacent electric leakage events corresponding to the same electric leakage cause. Through this calculation, the density of electric leakage events caused by the same electric leakage cause in time distribution can be understood, which is of great significance for judging the frequency of the electric leakage cause and whether it is effectively solved. For example, if the time interval between the electric leakage events corresponding to a certain electric leakage cause is short and occurs frequently, it means that the cause may not be completely solved and needs to be focused on.

[0135] For example, the cause of each electric leakage in the historical time is explicitly known, and the electric leakage cause can be various, such as insulation aging, external damage, environmental factors, improper maintenance, overvoltage and overload, etc. First, according to the cause of each electric leakage, all historical electric leakage events are classified, and the same induced cause is classified into a category, the number of electric leakage events of each classification is counted, and the time of each electric leakage and the duration are counted; the time interval between all electric leakage events in each classification is not necessarily long or short, if the fault factor is not completely eliminated, the equipment may appear again after a short time after the electric leakage is restored to normal, if the electric leakage is caused by external environmental intermittent changes, it may appear again after a long time; count the time interval between all electric leakage events in each classification, the shorter the interval, the more the number of times the cause appears and is not completely eliminated, the possibility of appearing later will be larger, which should be considered as a key reason.

[0136] The importance of each electric leakage cause can be represented as:

[0137]

[0138] Among them, represents the importance of the i-th electric leakage cause; represents the number of times of the occurrence of the electric leakage event corresponding to the i-th electric leakage cause; represents the total number of historical electric leakage events; represents the proportion of the electric leakage of the i-th electric leakage cause in the total electric leakage, The larger the value of, the more common the electric leakage of the i-th electric leakage cause is; represents the maximum time interval between adjacent electric leakage events in all electric leakage times of the i-th electric leakage cause, The smaller the value is, the more intensive the leakage of this reason occurs; the larger the leakage feature of the transformer in the historical time is, the more common the leakage of this reason is, and the smaller the maximum time interval between adjacent leakage events is, which means that the leakage event of this reason should be given higher importance, that is The larger the value is, the more common the leakage of this reason occurs.

[0139] In this embodiment, by classifying the leakage events according to the leakage reasons, the leakage situations caused by different leakage reasons can be clearly sorted out, which facilitates the targeted analysis of the influence of each reason on the electrical equipment and improves the orderliness and accuracy of the leakage reason analysis, thereby laying a foundation for accurately evaluating the importance of each leakage reason. The time interval between the leakage events corresponding to each leakage reason is determined according to the occurrence time and duration of each leakage event, which can analyze the action law of the leakage reason from the time dimension and understand its frequency and potential development trend. For example, a shorter time interval may mean that the leakage reason persists and has not been effectively handled, which needs to be focused on. This helps to more comprehensively and deeply evaluate the importance of each leakage reason and improves the pertinence and effectiveness of leakage monitoring. The importance of each leakage reason is determined by comprehensively considering the damage degree of the electrical equipment, the number of leakage events corresponding to each leakage reason, and the maximum time interval between adjacent leakage events, which makes the evaluation of the importance of the leakage reason more comprehensive and scientific. The key leakage reasons that have a greater impact on the electrical equipment can be accurately identified, so as to focus resources on these key reasons in the leakage monitoring and prevention work, effectively improve the accuracy of leakage monitoring, ensure the safe operation of the electrical equipment, and improve the safety of the electrical equipment.

[0140] In an embodiment of the present application, the change of the residual current before each leakage is analyzed according to the historical leakage data to obtain the residual current change feature corresponding to each leakage reason, including:

[0141] The reference current change amplitude of each leakage reason is determined according to the occurrence time and duration of each leakage event;

[0142] The change of the current with time is analyzed according to the second residual current sequence before each leakage event occurs to obtain the current change rate of each leakage event, the current change rate of each leakage event is clustered, and the reference current change rate of each leakage reason is determined according to the clustering result;

[0143] The current change rate of each leakage event is corrected according to the number of each leakage event belonging to the leakage reason, and the reference current change rate of each leakage reason is updated according to the corrected current change rate of each leakage event to obtain a new reference current change rate of each leakage reason;

[0144] The reference current change rate of each leakage cause is determined in combination with the reference current change amplitude of each leakage cause and the corresponding residual current change characteristic of each leakage cause.

[0145] The change of current over time refers to the change in the value of residual current on the time axis before the occurrence of a leakage event. Analyzing this change can help understand the dynamic trend of residual current before leakage occurs, which is important for predicting the occurrence of leakage. In the context of leakage monitoring of electrical equipment, observing whether the residual current gradually increases, suddenly changes, or remains stable over time can help determine the likelihood and type of leakage.

[0146] The current change rate is a physical quantity that measures the speed of change of residual current in a unit of time. It is obtained by calculating the ratio of the difference in residual current at adjacent times to the time interval, and it reflects the degree of change in residual current before leakage occurs. For example, the greater the current change rate, the more significant the change in residual current in a short period of time, which may indicate a more urgent leakage situation.

[0147] Clustering is a data analysis method that groups data points with similar characteristics into a class. In this context, clustering the current change rate of each leakage event means grouping leakage events with similar change rates into a group to identify the reference current change rate characteristics from numerous leakage events, providing a basis for determining the reference current change rate of each leakage cause.

[0148] The reference current change rate is a typical rate value that represents the speed of current change before leakage for a specific leakage cause, determined based on clustering analysis of the current change rates of multiple leakage events corresponding to each leakage cause. It is used to represent the general speed of residual current change under a specific leakage cause, which helps to determine whether this type of leakage is likely to occur by comparing the current change rate in subsequent monitoring.

[0149] The correction is a process of adjusting the obtained current change rate according to specific factors. In this application, it is to make the reference current change rate more accurately reflect the characteristics of each leakage cause, in order to improve the accuracy of leakage prediction.

[0150] According to the number of reasons for each leakage event, the current change rate of each leakage event is corrected. Since some leakage events may be caused by multiple reasons, the number of reasons for each leakage event is different. This feature refers to adjusting the current change rate according to the number, so that in the case of multiple reasons acting together, the current change rate can more accurately reflect the characteristics of the main leakage reason. For example, if a leakage event is caused by three reasons, and another is caused by only one reason, then when considering the reference of the current change rate to the leakage reason, the current change rate of the former is given a relatively small weight to highlight the current change rate characteristics of the leakage event dominated by a single reason, so as to more accurately determine the reference current change rate of each leakage reason.

[0151] In an embodiment of the present application, the reference current change amplitude of each leakage reason is determined according to the occurrence time and duration of each leakage event, comprising:

[0152] According to the occurrence time and duration of each leakage event, a minimum time interval is determined, and the minimum time interval is taken as a reference time interval;

[0153] For the leakage events of each leakage reason, a plurality of second residual current sequences corresponding to each leakage reason are obtained according to the second residual current sequence within the reference time interval before each leakage event occurs;

[0154] The difference between the maximum value and the minimum value in each second residual current sequence is taken as the current change amplitude of the leakage event;

[0155] The maximum current change amplitude in the plurality of second residual current sequences is taken as the reference current change amplitude of each leakage reason.

[0156] According to the occurrence time and duration of each leakage event, the minimum time interval can be determined by comparing and analyzing the occurrence time and duration of each leakage event to find the minimum value in the time interval between adjacent two leakage events or the time interval of different stages in a single leakage event. This minimum value reflects the minimum comparable interval of leakage events in the time dimension, and provides a benchmark time scale for subsequent unified analysis of residual current change. For example, in a series of leakage events, by calculating the interval between adjacent leakage events and different time points in a single leakage event, the shortest time interval is found.

[0157] Wherein, the reference time interval is to take the minimum time interval determined in the front as a standard time length. In the analysis of the residual current change characteristics, the residual current data sequence before each leakage event occurs is intercepted according to the time length, so that the residual current changes of different leakage events can be compared and analyzed in the same time scale, and the consistency and comparability of the analysis are guaranteed. For example, if the minimum time interval is determined to be 5 minutes, then the residual current change within 5 minutes before each leakage event is analyzed.

[0158] Wherein, the current change amplitude refers to the difference between the maximum value and the minimum value of the residual current in a specific time sequence (here, the second residual current sequence within the reference time interval before each leakage event occurs). It directly reflects the range of residual current fluctuation in this specific time period, and is an important indicator for measuring the degree of residual current change. For example, in a certain 5-minute reference time interval, the residual current changes from 10 mA to 20 mA, so the current change amplitude is 20 mA-10 mA=10 mA.

[0159] For example, the input current of the transformer will also change before the leakage event caused by different leakage reasons, and the leakage caused by different reasons will also make the input current of the transformer present different change characteristics, including the change rate of the current, the size of the change amplitude, the balance degree of the three-phase current, etc. In order to more accurately predict the leakage, the change characteristics of the current of the transformer when different leakage events occur also need to be understood. The current characteristics of different types of leakage are mainly determined from the current change rate and the change amplitude in this embodiment;

[0160] For example, when the insulation is aging or damaged, the current change is relatively slow, which is a gradual process, the change rate is small, and the current amplitude will gradually increase with the increase of the insulation damage degree, but there will be no instant large increase. The winding short circuit is a sudden fault, so the current of the short circuit phase will increase rapidly when the fault occurs, the current change rate is fast, and the current amplitude will increase greatly. The insulation resistance decreases after being wet, and the current change rate is also large, but compared with the change rate when the winding is short-circuited, the change rate will be slower, and the current amplitude will be smaller compared with the winding short circuit.

[0161] For all historical leakage events, the time interval between all adjacent two leakages is determined, the minimum time interval is recorded as the reference time interval, and is recorded as g.

[0162] For each leakage event of each leakage reason, the residual current sequence in the time before each event occurs for g is obtained, thereby obtaining a plurality of second residual current sequences corresponding to each leakage reason; the difference between the maximum value and the minimum value in each second residual current sequence is obtained, which is used to represent the current change amplitude of the leakage event, the maximum current change amplitude in all second residual current sequences is selected, which is denoted as , which is used to represent the reference current change amplitude of a certain leakage reason.

[0163] According to the second residual current sequence before each leakage event occurs, the current change rate between adjacent time points is obtained, and the representation of the current change rate between adjacent time points can be:

[0164]

[0165] wherein, represents the current change rate between adjacent time points; represents the current at the i th time point; represents the current at the i-1 th time point, represents the time interval between the i th and i-1 th time points (the time interval between all adjacent time points in the current sequence should be the same).

[0166] Thereby, the current change speed between all adjacent time points is obtained, and the mean value of all v is obtained, which is used to represent the current change rate before the leakage event occurs, denoted as v1.

[0167] Each leakage reason may contain multiple leakage events, so multiple v1 will be obtained, and all v1 are clustered to obtain the most numerous cluster, which is denoted as the reference cluster, and the mean value of all current change rates in the reference cluster is obtained, which is denoted as v2, and v2 can also be used to represent the reference current change rate of the leakage reason.

[0168] During the operation of the transformer, some leakage events may be caused by multiple reasons, so some leakage events may occur in different types of reasons, therefore, the number of leakage reasons to which each leakage event belongs is counted, which is denoted as w1, the greater the value of w1, the more reasons that cause the leakage, and the current change sequence before the leakage is less reliable, w1 is used as the initial weight to correct the current change rate before each leakage event occurs, and the weight can be used to weight the change rate of all leakage events to obtain the mean value, the reference current change rate v2 is updated to obtain a new reference current change rate of each leakage reason .

[0169] The residual current change characteristics corresponding to the leakage reason can be represented as:

[0170]

[0171] wherein, represents the residual current change characteristic corresponding to the lth leakage cause; represents the residual current change rate before the leakage event of the lth leakage cause occurs; represents the reference current change amplitude of the lth type of leakage event; the greater the reference current change rate and the greater the reference current change amplitude, the more obvious the residual current change before the occurrence of the leakage of this type, the greater the value of.

[0172] According to the above steps, the residual current change characteristic before the occurrence of each type of leakage is obtained.

[0173] In this embodiment, the change of current with time is analyzed and the current change rate is obtained, which can capture the dynamic information of the residual current change before leakage, provide a key basis for judging the leakage type and severity, and help improve the accuracy of leakage monitoring. By quantifying the current change rate, the analysis of the leakage situation is more accurate. The clustering method is used to determine the reference current change rate, which extracts the current change characteristics with reference from complex leakage event data, simplifies the data analysis process, and highlights the typical characteristics of current change under different leakage causes, which is convenient for subsequent comparison with real-time monitoring data and improves the pertinence and accuracy of leakage prediction. According to the number of each leakage event belonging to the leakage cause, the current change rate is corrected, which takes into account the situation that leakage in practice may be caused by multiple reasons, so that the reference current change rate more accurately reflects the real influence of each leakage cause, further optimizes the determination process of the residual current change characteristic, thereby improving the accuracy of leakage monitoring and prediction, ensuring the safe operation of electrical equipment, and improving the safety of electrical equipment use.

[0174] In an embodiment of the present application, the target leakage cause corresponding to the current time period is determined according to the residual current change characteristic corresponding to each leakage cause, and the data weight corresponding to the current time period is determined according to the importance of the target leakage cause, comprising:

[0175] obtaining a third residual current sequence of the electrical equipment at an interval of the reference time interval before the current time period;

[0176] determining the residual current difference according to the third residual current sequence and the preset residual current threshold, and fitting the change of the residual current of the electrical equipment in the current time period, and determining the residual current change trend according to the fitting result;

[0177] According to the third residual current sequence, the change of current over time is analyzed to obtain the current change rate of the electrical equipment in the current time period, and in combination with the current change amplitude corresponding to the third residual current sequence, the residual current change characteristic of the current time period is obtained;

[0178] The residual current change characteristic of the current time period is compared with the residual current change characteristic corresponding to each leakage reason to obtain a plurality of characteristic differences;

[0179] The plurality of characteristic differences are compared with a preset difference threshold, and the target leakage reason corresponding to the current time period is determined according to the comparison result, and the importance of the target leakage reason is determined;

[0180] In combination with the residual current difference, the residual current change trend, and the importance of the target leakage reason, the data weight corresponding to the current time period is determined.

[0181] Wherein, the third residual current sequence of the electrical equipment is obtained at an interval of the reference time interval before the current time period. It means that a sequence of residual current data is intercepted as a standard before the current monitoring time period with the previously determined reference time interval. This sequence contains the numerical information of the residual current of the electrical equipment in a specific time window, which is used to analyze the change of the residual current before the current time period, and provides historical data support for judging the current leakage possibility and reason. For example, if the reference time interval is 10 minutes, and the current time period is 10:00-10:30 am, then the residual current data from 9:50 am to 10:00 am is obtained to form the third residual current sequence.

[0182] Wherein, when fitting the change of the residual current of the electrical equipment in the current time period, fitting is a mathematical method that uses a specific function (such as a linear function, a polynomial function, etc.) to approximately describe the relationship between the residual current and time in the current time period. In this way, the change pattern of the residual current can be more clearly seen, and some random fluctuations in the data can be removed, so as to more accurately analyze the change trend of the residual current. For example, the linear regression method is used to fit the residual current data recorded every 1 minute in the current time period to obtain a linear equation to represent the change of the residual current over time.

[0183] Wherein, the residual current change trend is the change trend of the residual current over time reflected by the fitting result of the residual current change in the current time period, such as gradually rising, gradually falling, or remaining stable, etc. This trend is of great significance to determine whether the electrical equipment is likely to leak and the size of the leakage possibility. For example, the fitting result shows that the residual current increases linearly over time, indicating that there may be a gradually increasing risk of leakage.

[0184] In the comparison, the residual current variation feature calculated in the current time period is compared with the residual current variation feature corresponding to each leakage cause obtained in the previous analysis, and a difference value between them is obtained. Then the difference values are compared with the preset difference threshold. If the feature difference corresponding to a leakage cause is less than the preset threshold, it is indicated that the current residual current variation feature is similar to the feature corresponding to the leakage cause, and thus it can be determined that the target leakage cause corresponding to the current time period is possibly the leakage cause. For example, the preset difference threshold is 0.5, and the difference between the residual current variation feature in the current time period and the residual current variation feature corresponding to insulation aging is 0.4, which is less than the threshold, and thus it can be determined that the target leakage cause is insulation aging.

[0185] For example, after the historical leakage features of the transformer and the current variation features before the occurrence of different types of leakage events are determined, the measured transformer input current and residual current in a current time period are obtained, and the possibility of leakage of the transformer in a future time is predicted. The specific operation is as follows:

[0186] A third residual current sequence of the transformer in a time period of g before the current time is obtained.

[0187] An absolute value of a difference between the residual current at each time in the third residual current sequence and the preset residual current threshold is obtained, to obtain a residual current difference, denoted as j. The smaller the value of j is, the closer the residual current at the current time is to the residual current action threshold, and the more likely the leakage occurs.

[0188] A residual current variation straight line in the current time period is obtained by using the least square method, and a slope of the straight line is obtained as a residual current variation trend, denoted as k. The larger the value of k is, the more obvious the trend that the residual current gradually increases with time is, and the more likely the leakage accident occurs in the future.

[0189] A current variation amplitude corresponding to the third residual current sequence is obtained, denoted as .

[0190] A residual current variation speed between adjacent times in the current time period is obtained, denoted as v0, to obtain residual current variation speeds between all adjacent times, that is, a plurality of v0. An average value of all v0 is obtained, to represent a current variation rate of the electrical equipment in the current time period, denoted as Therefore, the residual current variation feature in the current time period can be represented as: .

[0191] In the above embodiments, the residual current change characteristics corresponding to the leakage causes have been determined according to historical leakage data, a plurality of B values are obtained, B0 is compared with each B value, and a feature difference is obtained. The representation of the feature difference can be:

[0192]

[0193] wherein, represents the feature difference between the residual current change characteristic of the current time period and the residual current change characteristic corresponding to the lth leakage cause, The smaller the value of is, the more similar the residual current change characteristic of the current time period is to the residual current change characteristic corresponding to the lth leakage cause, and the more likely the current time period is the lth leakage cause.

[0194] The value of is normalized to the range of 0-1 using a normalization function, and the current current change characteristic is compared with the residual current change characteristic corresponding to each leakage cause to obtain a plurality of The preset difference threshold is 0.3. When the values of a plurality of are all less than 0.3, it indicates that there may be multiple causes of leakage. The causes corresponding to all the leakage events whose values are less than 0.3 are determined as target leakage causes. The importance of the target leakage cause can be represented as:

[0195]

[0196] wherein, represents the importance of the target leakage cause; m represents the number of target leakage causes.

[0197] The data weight of each time point in the current time period can be represented as:

[0198]

[0199] wherein, represents the data weight of the s th time point in the current time period; represents the residual current difference value of the s th time point in the current time period; represents the residual current change trend in the current time period; represents the importance of the target leakage cause; is used to adjust the difference between the current residual current and the threshold according to the comprehensive characteristics in the entire time period; the closer the residual current is to the threshold, and the more gradually the residual current increases over time, the more important the matching leakage type is, and the greater the weight of this time point is.

[0200] ​​​In this embodiment, the third residual current sequence of a specific time interval is obtained, which provides recent historical data reference for analyzing the leakage situation of the current time period, and combined with the data of the current time period, the residual current change can be more comprehensively grasped, the accuracy of the leakage cause judgment is improved, and the accuracy of the leakage monitoring is improved. Fitting the residual current change in the current time period to determine the change trend can effectively remove data noise and clearly present the change trend of the residual current, helping to more accurately judge the development trend of the leakage risk, enhance the accuracy of the leakage possibility and severity judgment, and improve the reliability of the leakage monitoring. By comparing the current residual current change characteristics with the characteristics of each leakage cause, and comparing with the preset difference threshold to determine the target leakage cause, the current possible leakage cause can be quickly and accurately determined, and measures can be taken to prevent leakage accidents, improve the timeliness and effectiveness of leakage monitoring, and ensure the safe operation of electrical equipment, and improve the safety of electrical equipment use. The data weight is determined by comprehensively considering the residual current difference, change trend and importance of the target leakage cause, so that the influence of each factor can be more reasonably considered in subsequent leakage prediction, the accuracy of leakage prediction is improved, and the safe and stable operation of electrical equipment is better ensured.

[0201] In an embodiment of the present application, the plurality of feature differences are compared with the preset difference threshold, and the target leakage cause corresponding to the current time period is determined according to the comparison result, and the importance of the target leakage cause is determined.

[0202] When the comparison result is that the current time period corresponds to a plurality of target leakage causes, the importance of the target leakage cause is obtained based on the feature difference and the importance of each leakage cause.

[0203] For example, when the values of all are greater than 0.3, the leakage cause type corresponding to the smallest value is selected as the matching leakage type of the current time period, and at this time, the importance of the matching leakage type can be represented as:

[0204]

[0205] For example, assuming that an electrical equipment has three leakage causes of insulation aging, overvoltage and external damage, and the preset difference threshold is 0.4. The residual current change characteristics calculated in the current time period are 0.3, 0.35 and 0.25 corresponding to the feature differences of insulation aging, overvoltage and external damage respectively. Since the three feature differences are all less than the preset difference threshold 0.4, the current time period corresponds to multiple target leakage causes, i.e. insulation aging, overvoltage and external damage.

[0206] Assuming that the importance degree corresponding to the insulation aging of the leakage cause has been determined as 0.6, the importance degree corresponding to the overvoltage is 0.5, and the importance degree corresponding to the external force damage is 0.4. Based on these data, the comprehensive importance degree of the target leakage cause is re-determined. For example, a weighted average method (here is only an example method, and the calculation method can be set according to the specific situation) can be used, and the reciprocal of the feature difference is taken as the weight (because the smaller the feature difference, the more similar to the cause, the weight should be larger), the weight of insulation aging is 1 / 0.3, the weight of overvoltage is 1 / 0.35, and the weight of external force damage is 1 / 0.25. The comprehensive importance degree is calculated as: [(1 / 0.3)×0.6+(1 / 0.35)×0.5+(1 / 0.25)×0.4] ÷ [(1 / 0.3)+(1 / 0.35)+(1 / 0.25)]≈0.48. In this way, when there are multiple possible leakage causes, a value that comprehensively reflects the importance degree of each target leakage cause is obtained.

[0207] In the embodiment, when the comparison result shows that there are multiple target leakage causes, the importance degree of the target leakage cause is re-determined based on the feature difference and the original importance degree of each leakage cause, which is more comprehensive and detailed. In actual situations, the leakage of electrical equipment may be caused by multiple factors. This processing method can more accurately reflect the correlation between the current leakage situation and multiple possible causes, and improve the accuracy of leakage cause judgment. By considering multiple factors to determine the importance degree, it is helpful to more reasonably allocate resources and take measures in subsequent leakage monitoring and prevention work. For leakage cause combinations with high comprehensive importance degree, more attention and prevention are given in advance to avoid ignoring other potential risks by only considering a single cause, thereby more effectively ensuring the safe operation of electrical equipment and improving the safety of electrical equipment use. This method improves the adaptability and scientificity of the entire leakage monitoring method, can better cope with complex leakage situations, and further optimizes the leakage monitoring process, providing a more reliable basis for accurately predicting leakage risks.

[0208] In an embodiment of the present application, the leakage prediction of the electrical equipment according to the data weight corresponding to the current time period and the input current and residual current in the current time period obtains a leakage prediction result to realize the leakage monitoring of the electrical equipment, which comprises:

[0209] inputting the input current and residual current in the current time period and the data weight corresponding to the current time period into a pre-trained leakage prediction model to obtain a predicted residual current value;

[0210] when the predicted residual current value is greater than a preset residual current threshold, it is determined that there is a leakage risk.

[0211] The leakage prediction model is a model constructed based on a specific algorithm and pre-trained, which can comprehensively analyze various input data information such as input current, residual current and corresponding data weight in the current time period, and thus predict the future leakage situation of the electrical equipment. This model is usually trained using historical data to learn the correlation between different data combinations and leakage events, in order to improve the accuracy of prediction. For example, it can be a model based on machine learning algorithms such as artificial neural networks, support vector machines, etc., which is trained by a large amount of historical leakage data and corresponding input-output parameters, so as to have the ability to predict the leakage situation according to the current input data.

[0212] The predicted residual current value is a predicted value of the residual current at a certain time or time period in the future, obtained by the leakage prediction model through calculation and analysis based on the input current, residual current and data weight in the current time period. This value reflects the model's quantitative expression of the possibility of future leakage of electrical equipment, and is an important basis for determining whether there is a leakage risk. For example, if the predicted residual current value output by the model is 60mA, it means that the model predicts that the residual current of the electrical equipment may reach this value at the corresponding time or time period in the future.

[0213] When the predicted residual current value is greater than the preset residual current threshold value, it is determined that there is a leakage risk. The preset residual current threshold value is a residual current limit value pre-set according to the safety operation requirements of the electrical equipment and relevant standards. When the predicted residual current value output by the leakage prediction model exceeds this preset threshold value, it means that the electrical equipment may have a leakage situation and there is a risk of leakage. For example, if the preset residual current threshold value is 50mA and the predicted residual current value is 60mA, which is greater than the threshold value, it is determined that the electrical equipment has a leakage risk, and appropriate measures should be taken, such as further checking the equipment, cutting off the power supply in advance, etc., to ensure the safety of the equipment and personnel.

[0214] For example, the data weight of each time point in the current time period is obtained according to the above steps; the leakage prediction is performed using the ARIMA model: the residual current, the input current at each time point in the current time period, and the data weight at each time point are used as the input of the model, and the related parameters of the model are determined; after the related parameters are input, the corresponding output value can be obtained, and the output value is the prediction result of the related data of the transformer leakage in the future time or in the future period, for example, the future residual current value, which can be used to judge the possibility of future leakage; when the predicted residual current value exceeds the preset residual current action threshold, it means that the transformer has a high risk of leakage, which may cause serious safety accidents, so the power supply of the transformer can be cut off in advance, and the problem can be checked in time to avoid safety accidents such as electric shock and fire caused by leakage in the future, and prevent unnecessary harm and loss to production, personnel and equipment.

[0215] In this embodiment, by using the pre-trained leakage prediction model, the internal relationship between the historical data and the current real-time data can be fully utilized to scientifically and accurately predict the leakage of electrical equipment. Compared with the traditional method of simply judging the leakage condition according to a single index, the model greatly improves the accuracy and reliability of leakage prediction, thereby improving the overall effect of leakage monitoring. The predicted residual current value is used as a quantitative basis for judging the leakage risk, which provides an intuitive and explicit standard for evaluating the leakage possibility of electrical equipment. This value can reflect the future leakage trend of electrical equipment, so that the staff can have a clearer understanding of the running condition of the equipment according to the specific value, which facilitates timely taking appropriate measures and improves the operability of leakage monitoring. By setting a preset residual current threshold and comparing the predicted residual current value with the threshold to determine the leakage risk, a simple and effective judgment mechanism is provided for leakage monitoring. Once the predicted value exceeds the threshold, the leakage risk can be quickly judged, and appropriate protection measures such as alarm and power cut-off can be triggered in time, effectively avoiding safety accidents caused by leakage, ensuring the safe operation of electrical equipment and the safety of personnel and property, and improving the safety of electrical equipment use.

[0216] Figure 3 The structure diagram of the leakage monitoring device of the electrical equipment provided by an embodiment of the present application is shown in the figure. The device can be applied to Figure 1 The device can also be applied to other example implementation environments and specifically configured in other devices, and the implementation environment to which the device is applied is not limited in this embodiment.

[0217] As Figure 3 shown, the example leakage monitoring device of the electrical equipment includes:

[0218] The data acquisition module 301 is configured to acquire input current and residual current of the electrical equipment in a current time period and historical leakage data.

[0219] The leakage cause analysis module 302 is configured to analyze leakage causes of the electrical equipment according to the historical leakage data, to obtain historical leakage characteristics and an importance degree corresponding to each leakage cause.

[0220] The residual current change analysis module 303 is configured to analyze changes in residual current before each leakage according to the historical leakage data, to obtain a residual current change characteristic corresponding to each leakage cause.

[0221] The data weight determination module 304 is configured to determine a target leakage cause corresponding to the current time period according to the residual current change characteristic corresponding to each leakage cause, and determine a data weight corresponding to the current time period according to the importance degree corresponding to the target leakage cause.

[0222] The leakage prediction module 305 is configured to perform leakage prediction on the electrical equipment according to the data weight corresponding to the current time period and the input current and residual current in the current time period, to obtain a leakage prediction result, so as to realize leakage monitoring of the electrical equipment.

[0223] It should be noted that the leakage monitoring device of the electrical equipment provided in the above embodiments and the leakage monitoring method of the electrical equipment provided in the above embodiments belong to the same concept, and the specific manner in which each module and unit performs operations has been described in detail in the method embodiments, which will not be repeated here. The leakage monitoring device of the electrical equipment provided in the above embodiments can be used in actual applications, and the above functions can be completed by different functional modules according to needs, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above, and this is not limited herein.

[0224] Embodiments of the present application also provide an electronic device, comprising: one or more processors; a storage device configured to store one or more programs, when the one or more programs are executed by the one or more processors, the electronic device implements the leakage monitoring method of the electrical equipment provided in each of the above embodiments.

[0225] Figure 4 The structure diagram of the computer system suitable for the electronic device provided in an embodiment of the present application. It should be noted that, Figure 4 The computer system 400 of the electronic device shown is only an example, and should not limit the functions and use range of the embodiments of the present application.

[0226] As Figure 4As shown, the computer system 400 includes a central processing unit (CPU) 401 which can perform various appropriate actions and processes in accordance with programs stored in a read-only memory (ROM) 402 or programs loaded from the storage section 408 into a random access memory (RAM) 403, such as performing the methods described in the above embodiments. In the RAM 403, various programs and data required for the operation of the system are also stored. The CPU 401, the ROM 402, and the RAM 403 are connected to each other through a bus 404. An input / output (I / O) interface 405 is also connected to the bus 404.

[0227] Connected to the I / O interface 405 are an input section 406 including a keyboard, a mouse, etc.; an output section 407 including a display such as a Cathode Ray Tube (CRT), a Liquid Crystal Display (LCD), etc., and a speaker, etc.; a storage section 408 including a hard disk, etc.; and a communication section 409 including a network interface card such as a LAN (Local Area Network) card, a modem, etc. The communication section 409 performs communication processing via a network such as the Internet. A drive 410 is also connected to the I / O interface 405 as necessary. A removable recording medium 411 such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc. is attached to the drive 410 as necessary, so that a computer program read therefrom is installed into the storage section 408 as necessary.

[0228] In particular, according to embodiments of the present application, the processes described above with reference to the flowcharts can be implemented as a computer software program. For example, embodiments of the present application include a computer program product comprising a computer program carried on a computer readable medium, the computer program containing a computer program for executing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via the communication section 409, and / or installed from the removable recording medium 411. When the computer program is executed by the central processing unit (CPU) 401, various functions defined in the apparatus of the present application are performed.

[0229] It should be noted that the above-described order of the embodiments of the present application is merely for description, and does not represent the advantages and disadvantages of the embodiments. The processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multi-task processing and parallel processing are possible or can be advantageous.

[0230] The various embodiments described in this specification are presented by way of example, and each embodiment is not inherently more important than any other embodiment.

Claims

1. A method of leakage monitoring of an electrical device, characterized by, The method comprises: obtaining input current and residual current of the electrical equipment in a current time period and historical leakage data; analyzing leakage causes of the electrical equipment according to the historical leakage data to obtain historical leakage characteristics and importance degrees corresponding to each leakage cause; analyzing changes of the residual current before each leakage according to the historical leakage data to obtain residual current change characteristics corresponding to each leakage cause; determining a target leakage cause corresponding to the current time period according to the residual current change characteristics corresponding to each leakage cause, and determining a data weight corresponding to the current time period according to the importance degree corresponding to the target leakage cause; performing leakage prediction on the electrical equipment according to the data weight corresponding to the current time period and the input current and the residual current in the current time period to obtain a leakage prediction result, so as to realize leakage monitoring of the electrical equipment; the analyzing leakage causes of the electrical equipment according to the historical leakage data to obtain historical leakage characteristics and importance degrees corresponding to each leakage cause comprises: analyzing leakage intensity of the electrical equipment according to leakage information and leakage causes corresponding to a plurality of leakage events in the historical leakage data, and determining damage degree of the electrical equipment according to an analysis result of the leakage intensity, taking the damage degree as the historical leakage characteristics; performing importance analysis on each leakage cause according to the leakage events corresponding to each leakage cause and the damage degree of the electrical equipment to obtain the importance degree corresponding to each leakage cause; the performing importance analysis on each leakage cause according to the leakage events corresponding to each leakage cause and the damage degree of the electrical equipment to obtain the importance degree corresponding to each leakage cause comprises: classifying the leakage events according to the leakage causes to obtain a number of times of occurrence of the leakage events corresponding to each leakage cause, and occurrence time and duration of each leakage event; determining time intervals between the leakage events corresponding to each leakage cause according to the occurrence time and the duration of each leakage event, and determining a maximum time interval between adjacent leakage events corresponding to each leakage cause according to the time intervals between the leakage events corresponding to each leakage cause; determining the importance degree corresponding to each leakage cause in combination with the damage degree of the electrical equipment, the number of times of occurrence of the leakage events corresponding to each leakage cause and the maximum time interval between adjacent leakage events corresponding to each leakage cause; the analyzing changes of the residual current before each leakage according to the historical leakage data to obtain residual current change characteristics corresponding to each leakage cause comprises: determining a reference current change amplitude of each leakage cause according to the occurrence time and the duration of each leakage event; According to the second residual current sequence before the occurrence of each electric leakage event, the change of current over time is analyzed to obtain a current change rate of each electric leakage event, and the current change rate of each electric leakage event is clustered to determine a reference current change rate of each electric leakage cause according to the clustering result; According to the number of electric leakage causes to which each electric leakage event belongs, the current change rate of each electric leakage event is corrected, and the reference current change rate of each electric leakage cause is updated according to the corrected current change rate of each electric leakage event to obtain a new reference current change rate of each electric leakage cause; The new reference current change rate of each electric leakage cause is combined with the reference current change amplitude of each electric leakage cause to determine the corresponding residual current change characteristic of each electric leakage cause.

2. The electric leakage monitoring method of an electric appliance according to claim 1, wherein The input current and residual current of the electrical equipment in the current time period are obtained, including: Obtaining the input current requirement, measurement accuracy requirement, application scenario information and protection requirement corresponding to the electrical equipment; According to the input current requirement and the measurement accuracy requirement, a target current sensor is determined, and the input current of the electrical equipment in the current time period is obtained through the target current sensor, wherein the measurement probe of the target current sensor is perpendicular to the current line of the input current of the electrical equipment; According to the application scenario information and the protection requirement, a target electronic leakage protection device is determined, the input power line of the electrical equipment is connected to the input end of the target electronic leakage protection device, and the output end of the target electronic leakage protection device is linked to the input end of the electrical equipment to obtain the residual current of the electrical equipment in the current time period.

3. The electric leakage monitoring method of the electric appliance according to claim 1, wherein According to the leakage information and leakage cause corresponding to the plurality of electric leakage events in the historical electric leakage data, the electric leakage intensity of the electrical equipment is analyzed, and the damage degree of the electrical equipment is determined according to the analysis result of the electric leakage intensity, including: According to the historical electric leakage data, the number of the plurality of electric leakage events and the electric leakage residual current corresponding to each electric leakage event and the electric leakage time interval between adjacent electric leakage events are determined; According to the number of the plurality of electric leakage events and the electric leakage residual current corresponding to each electric leakage event, a first residual current sequence is established; According to the number of the plurality of electric leakage events and the electric leakage time interval between adjacent electric leakage events, a first time interval sequence is established; The first residual current sequence and the first time interval sequence are respectively subjected to difference calculation to obtain a first residual current difference sequence and a first time interval difference sequence; According to the mean value of the first residual current difference sequence and the mean value of the first time interval difference sequence, the electric leakage intensity of the electrical equipment is determined; According to the number of electric leakage causes and the electric leakage intensity of the electrical equipment, the damage degree of the electrical equipment is determined.

4. The electric leakage monitoring method of the electric appliance according to claim 1, wherein The reference current change amplitude of each electric leakage cause is determined according to the occurrence time and duration of each electric leakage event, including: According to the occurrence time and duration of each electric leakage event, a minimum time interval is determined as a reference time interval; For the electric leakage event of each electric leakage cause, a plurality of second residual current sequences corresponding to each electric leakage cause are obtained according to the second residual current sequence within the reference time interval before each electric leakage event occurs; The difference between the maximum value and the minimum value in each second residual current sequence is taken as the current change amplitude of the electric leakage event; The maximum current change amplitude in the plurality of second residual current sequences is taken as the reference current change amplitude of each electric leakage cause.

5. The electric leakage monitoring method of the electric appliance according to claim 4, wherein According to the residual current change characteristics corresponding to each electric leakage cause, the target electric leakage cause corresponding to the current time period is determined, and according to the importance degree of the target electric leakage cause, the data weight corresponding to the current time period is determined, including: A third residual current sequence of the electrical equipment is obtained at an interval of the reference time interval before the current time period; According to the third residual current sequence and the preset residual current threshold, a residual current difference value is determined, and the change of the residual current of the electrical equipment in the current time period is fitted, and the residual current change trend is determined according to the fitting result; According to the third residual current sequence, the change of the current with time is analyzed to obtain the current change rate of the electrical equipment in the current time period, and the residual current change characteristics of the current time period are obtained in combination with the current change amplitude corresponding to the third residual current sequence; The residual current change characteristics of the current time period are compared with the residual current change characteristics corresponding to each electric leakage cause to obtain a plurality of feature differences; The plurality of feature differences are compared with a preset difference threshold, and the target electric leakage cause corresponding to the current time period is determined according to the comparison result, and the importance degree of the target electric leakage cause is determined; The data weight corresponding to the current time period is determined in combination with the residual current difference value, the residual current change trend, and the importance degree of the target electric leakage cause.

6. The electric leakage monitoring method of the electric appliance according to claim 5, wherein The plurality of feature differences are compared with a preset difference threshold, and the target electric leakage cause corresponding to the current time period is determined according to the comparison result, and the importance degree of the target electric leakage cause is determined, including: When the comparison result is a plurality of target electric leakage causes corresponding to the current time period, the importance degree of the target electric leakage cause is obtained based on the feature difference and the importance degree corresponding to each electric leakage cause.

7. The electric leakage monitoring method of the electric appliance according to claim 6, wherein According to the data weight corresponding to the current time period, and the input current and residual current in the current time period, the electric leakage of the electrical equipment is predicted to obtain an electric leakage prediction result, so as to realize the electric leakage monitoring of the electrical equipment, including: The input current and residual current in the current time period, and the data weight corresponding to the current time period, are input into a pre-trained electric leakage prediction model to obtain a predicted residual current value; When the predicted residual current value is greater than a preset residual current threshold, it is determined that there is an electric leakage risk.

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