A comprehensive monitoring method for distribution network operation status

Abstract

The present invention discloses a method and system for comprehensive monitoring of the operating status of a distribution network, the method comprising: dividing the distribution network into multiple line segments based on the location information of the monitoring node, obtaining the line loss data of each line segment; determining the operating characteristics of the corresponding line segment according to the line loss data; determining the operating status analysis method of the line segment based on the operating characteristics of each line segment; and using the corresponding operating status analysis method to perform comprehensive monitoring of the operating status of each line segment of the distribution network. This method analyzes the operating characteristics of the distribution network from a global dimension based on the power transmission quality of the line loss data, considers the correlation between the monitoring indicators and the local characteristic differences between the monitoring point and the surrounding neighborhood under different operating characteristics, and adopts different strategies to obtain the comprehensive monitoring results of the operating status of the distribution network. The use of targeted monitoring strategies and multi-dimensional features effectively improves the accuracy and efficiency of distribution network monitoring and reduces the false alarm rate.

Description

Technical Field

[0001] The present invention relates to the technical field of power data processing, and in particular to a method for comprehensively monitoring the operating status of a distribution network. Background Art

[0002] The distribution network operation status monitoring can grasp the evolution process of potential faults of power equipment in the power grid and guide operation and maintenance personnel to arrange preventive maintenance before failure, so as to extend the operation cycle and reduce the operation risk of the distribution network.

[0003] The means of abnormal monitoring in the existing technology are almost all achieved through abnormal thresholds and data fluctuations. They are too dependent on the algorithm itself and are limited to the waveform anomalies shown by the electrical parameters themselves. Since the weights are allocated based on experience, the comprehensive evaluation index obtained by fusion depends on the experience level of the detection personnel. At the same time, the operating status of the distribution network units is complex and changeable during service, and there are usually large differences in operating parameters under different operating conditions. The simple threshold division method does not consider the operating conditions of the unit to set the alarm threshold, resulting in wide upper and lower limits of the threshold. It is difficult to accurately judge whether the operating status of the distribution network is normal or not using this threshold. The system has a high false alarm rate and is not very practical in actual fault prediction. Summary of the invention

[0004] In view of the problems existing in the above-mentioned prior art, the present invention provides a method and system for comprehensively monitoring the operating status of a distribution network. The method uses line loss data to analyze the real-time transmission quality of the distribution network as an operating condition feature, and selects different monitoring methods according to different operating condition features to perform comprehensive monitoring of the operating status of the distribution network.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] In a first aspect, the present invention provides a method for comprehensive monitoring of the operation status of a distribution network, comprising:

[0007] The distribution network is divided into multiple line segments based on the location information of the monitoring nodes, and the line loss data of each line segment is obtained;

[0008] Determining the operating characteristics of the corresponding line section according to the line loss data;

[0009] Determining an operation status analysis method of each line segment based on the operating characteristics of the line segment, wherein the operation status analysis method includes a threshold warning method and an outlier detection method;

[0010] The corresponding operating status analysis method is used to perform comprehensive monitoring of the operating status of each line section of the distribution network.

[0011] Preferably, the line loss data includes a line loss rate, a line loss change rate, and a line loss offset, and the acquiring of the line loss data of each line segment includes:

[0012] Acquiring electrical parameters of the line section based on a monitoring period;

[0013] According to the electrical parameters of each line section, the supplied electric energy at the starting point of the line section and the output electric energy at the end point of the line section are calculated to obtain the line loss rate of each line section;

[0014] A line loss variation curve is drawn according to the line loss rate of different monitoring periods, wherein the slope of the line loss variation curve represents the line loss variation rate;

[0015] The line loss variation curve is overlapped and compared with a preset line loss curve and a no-load loss curve to obtain a line loss offset.

[0016] Preferably, determining the operating condition characteristics of the corresponding line section according to the line loss data includes:

[0017] Acquiring the cable status based on cable temperature monitoring, analyzing the abnormality of the line loss based on the line loss rate, analyzing the operation disturbance based on the line loss change rate, and analyzing the abnormality of the load based on the line loss offset;

[0018] The operating characteristics of the corresponding line section are determined based on the cable status, the abnormal line loss, the operation disturbance, and the abnormal load.

[0019] Preferably, the determining of the operating condition characteristics of the corresponding line section based on the cable status, the line loss abnormality, the operation disturbance, and the load abnormality includes:

[0020] When the abnormal line loss condition is an increase in line loss and the operating disturbance condition is a non-periodic sudden increase, the operating condition characteristic of the line section is determined to be a transient instability condition;

[0021] When the abnormal line loss condition is an increase in line loss, the abnormal load condition is an excessive load, and the cable state condition has a continuous high temperature, the operating condition characteristic of the line section is determined to be an overload operating condition;

[0022] When the abnormal line loss condition is an increase in line loss, the abnormal load condition is an insufficient load, and the cable status condition has a local hot spot, the operating condition characteristic of the line section is determined to be a no-load operating condition;

[0023] When the cable status is abnormal and does not meet the operating characteristics of the transient instability condition, the overload operating condition, and the no-load operating condition, the operating characteristics of the line section are determined to be abnormal cable conditions.

[0024] Preferably, the method for analyzing the operating status of each line segment based on the operating characteristics of the line segment includes:

[0025] When the operating condition characteristic of the line section is the transient instability condition, an alarm is issued for the operating status of the line section based on the correlation between the electrical parameters of the line section;

[0026] When the operating condition of the line section is characterized by the overload operating condition or the no-load operating condition, a threshold warning method is used to analyze the operating state of the line section, and different threshold boundaries are set according to the importance of each monitoring indicator under different operating condition characteristics;

[0027] When the operating condition of the line segment is characterized by the abnormal cable operating condition, the operating status of the line segment is analyzed by using an outlier detection method based on the characteristics of the neighborhood points of each monitoring point on the line segment.

[0028] Preferably, when the operating condition characteristic of the line section is the transient instability condition, providing an alarm prompt for the operating status of the line section based on the correlation between the voltage and current parameters of the line section includes:

[0029] Analyze the parameter correlation between the real-time voltage and current of the line section;

[0030] If the parameter correlation is negative, a short circuit fault alarm is issued.

[0031] If the parameter correlation is positively correlated, a voltage compensation alarm is issued;

[0032] Preferably, when the operating condition characteristic of the line section is the overload operating condition or the no-load operating condition, a threshold warning method is used to analyze the operating state of the line section, and different threshold boundaries are set according to the importance of each monitoring indicator under different operating condition characteristics, including:

[0033] Calculate the correlation between each monitoring indicator and the corresponding working condition characteristic quantity and sort them from large to small;

[0034] Select the first k monitoring indicators, normalize the correlation of these monitoring indicators as importance weights to obtain comprehensive monitoring indicators, where k is a preset parameter;

[0035] The threshold boundary of the comprehensive monitoring indicator is set based on the maximum value of the historical data of the comprehensive monitoring indicator under the normal operating state of the line section.

[0036] As a preference,

[0037] When the operating condition characteristic of the line section is the overload operating condition, the operating condition characteristic quantity is selected as the cable temperature;

[0038] When the operating condition characteristic of the line section is the no-load operating condition, the operating condition characteristic quantity selects the power factor.

[0039] Preferably, when the working condition characteristic of the line segment is the abnormal working condition of the cable, analyzing the operating state of the line segment by using an outlier detection method based on the characteristics of the neighborhood points of each monitoring point on the line segment includes:

[0040] Obtain the spatial neighboring points and temporal neighboring points of the monitoring point to form a neighborhood set;

[0041] Calculate the distance between the monitoring point and each point in its neighborhood set under each monitoring indicator and sum them up;

[0042] The average value of the distance and the distance is used as the kernel function bandwidth and the kernel density estimation method is used to calculate the local density of the monitoring point to obtain the possibility that the monitoring point belongs to an outlier.

[0043] Locate the location of cable anomalies based on outliers in the line segment.

[0044] In a second aspect, the present invention provides a comprehensive monitoring system for distribution network operation status, comprising:

[0045] A data acquisition module, used to divide the distribution network into multiple line segments based on the location information of the monitoring node, and obtain the line loss data of each line segment;

[0046] A working condition analysis module, used to determine working condition characteristics of a corresponding line section according to the line loss data;

[0047] A strategy selection module, used to determine an operation status analysis mode of each line segment based on the operating characteristics of the line segment, wherein the operation status analysis mode includes a threshold warning mode and an outlier detection mode;

[0048] The operation monitoring module is used to perform comprehensive operation status monitoring on each line segment of the distribution network by adopting the corresponding operation status analysis method.

[0049] The invention provides a comprehensive monitoring method for the operation status of a distribution network, which has the following beneficial effects:

[0050] 1. The present invention uses the changing characteristics of line loss data to represent the real-time power transmission quality of the distribution network, and uses the power transmission quality to correspond to the quality of the working condition characteristics. Since the line working condition is the result of the coupling of multiple devices and multi-dimensional attributes, the present invention analyzes the characteristics of different working conditions from a global level. Compared with the prior art that uses characteristic values ​​of different attributes to divide working conditions, it does not require attribute parameter identification of a single power device, nor does it require analysis of the correlation between different attributes, so that accurate working condition characteristics can be simply and efficiently divided.

[0051] 2. The present invention takes into account that the operating parameters of the distribution network usually vary greatly under different operating conditions. Therefore, different strategies are selected based on the operating condition characteristics to monitor the operating status of the distribution network. The threshold is set by analyzing the contribution of each monitoring indicator to the global performance of the operating condition characteristics. The anomaly is located by associating the characteristic differences between the monitoring point and the surrounding neighborhood. This solves the limitations of a single evaluation standard when monitoring the operating status of the distribution network, the difficulty in detecting outliers when the density distribution of the data set is diverse, and the adaptive sensitivity of the threshold parameters. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 It is a flow chart of a comprehensive monitoring method for the operation status of a distribution network according to the present invention;

[0053] Figure 2 The invention discloses a structural block diagram of a comprehensive monitoring system for the operation status of a distribution network. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0055] To facilitate understanding of this embodiment, a method for comprehensive monitoring of the operating status of a distribution network disclosed in an embodiment of the present invention is first introduced in detail.

[0056] The embodiment of the present invention provides a method for comprehensive monitoring of the operation status of a distribution network. Figure 1 As shown, including:

[0057] The distribution network is divided into multiple line segments based on the location information of the monitoring nodes, and the line loss data of each line segment is obtained;

[0058] The operating conditions of distribution network equipment in different sections on a line have different time patterns and spatial correlations, so the operating conditions at each point on the line may be different. However, it is too cumbersome to identify the operating conditions of each device in the distribution network. This application considers taking the line segment as the monitoring unit and analyzing all the power equipment on a line segment as a whole. Based on the line loss data of each line segment, it can better reflect the individual differences in loads on each line segment and the actual transmission quality differences, and improve the pertinence of the operation status assessment.

[0059] Among them, line loss refers to the power loss caused by the resistance and inductance of cables, transformers and other equipment during the power transmission process of the power grid. The causes include the electrical characteristics of the cable itself, aging damage, cable overload, short circuit fault, etc.

[0060] In some specific implementations, the distribution network is divided into several branches by line switches, with two monitoring points on a power branch as the starting and ending points, and several monitoring points (set according to actual monitoring needs) in between, and each power branch of the distribution network is divided into multiple line segments.

[0061] Specifically, the line loss data includes a line loss rate, a line loss change rate, and a line loss offset. The acquiring of the line loss data of each line segment includes:

[0062] Acquiring electrical parameters of the line section based on a monitoring period;

[0063] According to the electrical parameters of each line section, the supplied electric energy at the starting point of the line section and the output electric energy at the end point of the line section are calculated to obtain the line loss rate of each line section;

[0064]

[0065] in, is the line loss rate, Supplying electrical energy to the starting point of the line segment, is the output power at the end point of the line segment.

[0066] A line loss variation curve is drawn with the line loss rate as the y-axis and the monitoring time as the x-axis, wherein the slope of the line loss variation curve represents the line loss variation rate;

[0067] The line loss variation curve is overlapped and compared with a preset line loss curve and a no-load loss curve to obtain a line loss offset.

[0068] It should be noted that the preset line loss curve is the line loss curve of the line section in the same historical period, and the no-load loss curve is the line loss curve of each basic electrical component of the line section under no-load conditions, and the basic electrical components include cables, transformers, etc.

[0069] The line loss variation curve is overlapped and compared with a preset line loss curve and a no-load loss curve to obtain a relative line loss offset and an absolute line loss offset.

[0070] In a specific implementation, the step of obtaining the line loss offset by overlap comparison is:

[0071] Obtaining a closed area S1 enclosed by a line loss variation curve and a coordinate axis, and a closed area S2 enclosed by a preset line loss curve and a coordinate axis;

[0072] Calculate the union area and the intersection area of ​​S1 and S2, and record the difference between the union area and the intersection area as the relative line loss offset;

[0073] The area of ​​the closed region below the line loss variation curve and above the no-load loss curve is obtained and recorded as the absolute line loss offset.

[0074] Determining the operating characteristics of the corresponding line section according to the line loss data;

[0075] It should be understood that the generation of line loss is closely related to the various load devices and cable status in the circuit, and is an important indicator for measuring the power transmission capacity of the power grid and the quality of power supply. Therefore, this application uses line loss data to characterize the power transmission quality on the line segment, that is, the larger the line loss data, the more abnormal the working condition.

[0076] Determining an operation status analysis method of each line segment based on the operating characteristics of the line segment, wherein the operation status analysis method includes a threshold warning method and an outlier detection method;

[0077] It should be noted that the operating characteristics based on transmission quality are the macroscopic manifestations of the line segment, and the numerical monitoring of the operating status is the microscopic analysis of the line segment. Threshold warning and / or outlier detection can accurately capture abnormal points in the distribution network.

[0078] The corresponding operating status analysis method is used to perform comprehensive monitoring of the operating status of each line section of the distribution network.

[0079] The operating status of distribution network units is complex and changeable. Usually, there are large differences in operating parameters under different working conditions. Therefore, the range definition of abnormal parameters under different working conditions is also different. This application determines the working condition characteristics through line loss data, uses different monitoring standards for monitoring indicators under different working condition characteristics, and realizes comprehensive monitoring of distribution network operating status based on working condition identification.

[0080] Preferably, determining the operating condition characteristics of the corresponding line section according to the line loss data includes:

[0081] Acquiring the cable status based on cable temperature monitoring, analyzing the abnormality of the line loss based on the line loss rate, analyzing the operation disturbance based on the line loss change rate, and analyzing the abnormality of the load based on the line loss offset;

[0082] The operating characteristics of the corresponding line section are determined based on the cable status, the abnormal line loss, the operation disturbance, and the abnormal load.

[0083] It should be noted that the abnormal cable status includes cable overheating, damage, and aging, which is manifested as abnormal temperature rise of the cable. The temperature of the cable is obtained through a pre-set temperature sensor to determine whether the cable status is abnormal. Among them, cable overheating can be divided into local hot spots and continuous high temperature.

[0084] It should be noted that the abnormal line loss conditions include increased line loss and negative line loss.

[0085] When the line loss rate is positive and greater than the preset line loss rate, that is, the line loss increases compared to the standard line loss rate threshold, it means that the line has abnormal operating conditions.

[0086] When the line loss rate is negative, that is, the output electric energy obtained is greater than the supplied electric energy, it is an abnormality of the total meter. It may be caused by total meter measurement errors or wiring errors, etc. It has little correlation with the operating conditions of the line itself and is not considered in this application.

[0087] It should be noted that the operating disturbance conditions include periodic changes, non-periodic micro-motions and non-periodic sudden increases in line loss.

[0088] Specifically, the periodic fluctuations in line loss are caused by the periodic fluctuations in power consumption of users, and the non-periodic micro-movements in line loss are caused by the natural deviations in the operation of power equipment. When the non-periodic sudden increase in line loss occurs, the transmission line has an operational disturbance, which may be caused by a line short circuit fault or a voltage drop.

[0089] It should be noted that the abnormal load condition includes excessive load and insufficient load.

[0090] When the load of the line section increases, the load power will increase, and the current flowing in the line will increase; at the same time, the resistance loss and inductance voltage drop in the cable will increase, and the line loss will increase significantly compared with the same period in history, that is, the relative line loss offset is large;

[0091] When the line loss of a line section is close to the no-load loss curve, that is, when the absolute line loss offset is very small, it indicates that the line section is underloaded and the energy generated by the line is wasted.

[0092] Preferably, the determining of the operating condition characteristics of the corresponding line section based on the cable status, the line loss abnormality, the operation disturbance, and the load abnormality includes:

[0093] When the abnormal line loss condition is an increase in line loss and the operating disturbance condition is a non-periodic sudden increase, the operating condition characteristic of the line section is determined to be a transient instability condition;

[0094] When the abnormal line loss condition is an increase in line loss, the abnormal load condition is an excessive load, and the cable state condition has a continuous high temperature, the operating condition characteristic of the line section is determined to be an overload operating condition;

[0095] When the abnormal line loss condition is an increase in line loss, the abnormal load condition is an insufficient load, and the cable status condition has a local hot spot, the operating condition characteristic of the line section is determined to be a no-load operating condition;

[0096] When the cable status is abnormal and does not meet the operating characteristics of the transient instability condition, the overload operating condition, and the no-load operating condition, the operating characteristics of the line section are determined to be abnormal cable conditions.

[0097] Preferably, the method for analyzing the operating status of each line segment based on the operating characteristics of the line segment includes:

[0098] When the operating condition characteristic of the line section is the transient instability condition, an alarm is issued for the operating status of the line section based on the correlation between the electrical parameters of the line section;

[0099] Transient instability conditions and cable abnormal conditions are line faults that require timely alarm processing, and in cable abnormal conditions, the abnormal location needs to be located in time. Load-related conditions require early warning judgments based on the values ​​of monitoring indicators according to different conditions.

[0100] When the operating condition of the line section is characterized by the overload operating condition or the no-load operating condition, a threshold warning method is used to analyze the operating state of the line section, and different threshold boundaries are set according to the importance of each monitoring indicator under different operating condition characteristics;

[0101] When the line section is overloaded or empty, the characteristics of the monitoring points on the entire line section are similar, that is, they are outliers compared to the normal operating data, but they are normal points compared to the neighboring point data, which is not suitable for outlier detection. The indicator threshold warning can intuitively observe the degree to which the current monitoring indicator deviates from the normal value, and setting a dynamic threshold boundary according to the load size can effectively reduce the false alarm rate.

[0102] When the operating condition of the line segment is characterized by the abnormal cable operating condition, the operating status of the line segment is analyzed by using an outlier detection method based on the characteristics of the neighborhood points of each monitoring point on the line segment.

[0103] When an abnormality occurs in a cable, most points on the cable have exceeded the abnormal threshold. It is necessary to locate the abnormal position in time, that is, to find the outliers on the line segment. At this time, it is more inclined to analyze the local characteristic differences of the cable.

[0104] It should be understood that the threshold warning is based on the comparison of the numerical characteristics of the overall monitoring indicators of the line section with historical data, while the outlier detection is based on the inspection of the monitoring point with other surrounding points to measure the abnormality of the monitoring point and then determine the abnormal location.

[0105] Preferably, when the operating condition characteristic of the line section is the transient instability condition, providing an alarm prompt for the operating status of the line section based on the correlation between the voltage and current parameters of the line section includes:

[0106] Analyze the parameter correlation between the real-time voltage and current of the line section;

[0107] If the parameter correlation is negative, a short circuit fault alarm is issued.

[0108] If the parameter correlation is positively correlated, a voltage compensation alarm is issued;

[0109] From circuit knowledge, we know that the operation disturbance may be caused by a line short circuit fault or a voltage drop. When a line short circuit fault occurs, the current on the electrical equipment and transmission line between the fault point and the power supply will increase from the load current to much more than the load current; the voltage at each point of the line drops, and the closer to the short circuit point, the lower the voltage. That is, when a line short circuit fault occurs, the changes in current and voltage are negatively correlated, and when the voltage drops, the current and voltage drop simultaneously.

[0110] Preferably, when the operating condition characteristic of the line section is the overload operating condition or the no-load operating condition, a threshold warning method is used to analyze the operating state of the line section, and different threshold boundaries are set according to the importance of each monitoring indicator under different operating condition characteristics, including:

[0111] Calculate the correlation between each monitoring indicator and the corresponding working condition characteristic quantity and sort them from large to small;

[0112] The monitoring index refers to the characteristic quantity used to measure the operating status of the distribution network.

[0113] In a specific implementation, the maximum mutual information coefficient may be used to calculate the correlation between each monitoring indicator and the cable temperature. The maximum mutual information coefficient is an existing technology and will not be described in detail in this embodiment.

[0114] Select the first k monitoring indicators, normalize the correlation of these monitoring indicators as importance weights to obtain comprehensive monitoring indicators, where k is a preset parameter;

[0115] Too much monitoring data is redundant, so only the monitoring indicators with greater contributions are selected for analysis in this embodiment. At the same time, since the influence of each monitoring indicator on the line operation status is different, directly integrating the monitoring indicator information and ignoring its importance will lead to an inaccurate description of the operation status.

[0116] The threshold boundary of the comprehensive monitoring indicator is set based on the maximum value of the historical data of the comprehensive monitoring indicator under the normal operating state of the line section.

[0117] As a preference,

[0118] When the operating condition characteristic of the line section is the overload operating condition, the operating condition characteristic quantity is selected as the cable temperature;

[0119] When the operating condition characteristic of the line section is the no-load operating condition, the operating condition characteristic quantity selects the power factor.

[0120] When overloaded, line abnormalities are mainly manifested as overheating. When some of these monitoring indicators make a greater contribution to the temperature rise, these monitoring indicators should be paid attention to first and have a higher importance for operating status monitoring.

[0121] When running at no-load, the load current of the line is very small, mainly composed of magnetizing current and loss current. The reactive component of the no-load current is large, while the active component is very small. Therefore, the line abnormality is mainly manifested as a low power factor, which is used as the performance indicator of the operating status at this time.

[0122] Preferably, when the working condition characteristic of the line segment is the abnormal working condition of the cable, analyzing the operating state of the line segment by using an outlier detection method based on the characteristics of the neighborhood points of each monitoring point on the line segment includes:

[0123] Obtain the spatial neighboring points and temporal neighboring points of the monitoring point to form a neighborhood set;

[0124] The neighborhood points are determined according to the size of the space and time monitoring period in actual application.

[0125] Calculate the distance between the monitoring point and each point in its neighborhood set under each monitoring indicator and sum them up;

[0126] The average value of the distance and the distance is used as the kernel function bandwidth and the kernel density estimation method is used to calculate the local density of the monitoring point to obtain the possibility that the monitoring point belongs to an outlier.

[0127]

[0128] in, is the kernel function bandwidth, For the Monitoring indicators, Represents the set of all monitoring indicators. is the number of monitoring indicators, represents the Euclidean distance between two points, Indicates monitoring point The neighborhood set of Indicates monitoring point A neighborhood point of Indicates monitoring point The number of neighboring points of Indicates monitoring point No. The value of the monitoring indicator, Indicate point No. The value of a monitoring indicator.

[0129]

[0130] in, represents a kernel function, and this embodiment adopts a Gaussian kernel function. Other kernel functions may be selected in actual implementation, and this application does not limit this. Other symbols are the same as above and will not be repeated.

[0131] Locate the location of cable anomalies based on outliers in the line segment.

[0132] When an abnormality occurs in a cable, it is necessary to pay more attention to changes in local or neighborhood features. At this time, the outlier detection bandwidth should be as small as possible so that the location of the cable abnormality can be accurately found.

[0133] It should be understood that, although the various steps in the flowcharts involved in the above-mentioned embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments can include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0134] Based on the same inventive concept, the embodiment of the present application also provides a system for implementing the above-mentioned method for comprehensive monitoring of the operation status of the distribution network. The implementation scheme for solving the problem provided by the system is similar to the implementation scheme recorded in the above-mentioned method, so the specific limitations of one or more distribution network operation status comprehensive monitoring systems provided below can refer to the limitations of the distribution network operation status comprehensive monitoring method above, and will not be repeated here.

[0135] like Figure 2 As shown, the present invention also provides a comprehensive monitoring system for distribution network operation status, including:

[0136] A data acquisition module, used to divide the distribution network into multiple line segments based on the location information of the monitoring node, and obtain the line loss data of each line segment;

[0137] A working condition analysis module, used to determine working condition characteristics of a corresponding line section according to the line loss data;

[0138] A strategy selection module, used to determine an operation status analysis mode of each line segment based on the operating characteristics of the line segment, wherein the operation status analysis mode includes a threshold warning mode and an outlier detection mode;

[0139] The operation monitoring module is used to perform comprehensive operation status monitoring on each line segment of the distribution network by adopting the corresponding operation status analysis method.

[0140] It should be noted that: the distribution network operation status comprehensive monitoring method system provided in this embodiment only uses the division of the above-mentioned functional modules as an example to illustrate the distribution network monitoring problem. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the system can be divided into different functional modules. Each functional module can be composed of a single execution unit, or it can be integrated into a functional module by two or more execution units to realize all the functions of the functional module.

[0141] It can be understood by those skilled in the art that each module in the above-mentioned distribution network operation status comprehensive monitoring system can be implemented in whole or in part by software, hardware and a combination thereof. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory in the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.

[0142] The present invention is not limited to the above-mentioned specific implementation modes. Various changes made by ordinary technicians in this field based on the above-mentioned concepts without creative work are all within the protection scope of the present invention.

Claims

1. A method for comprehensive monitoring of the operation status of a distribution network, characterized in that: include: The distribution network is divided into multiple line segments based on the location information of the monitoring nodes, and the line loss data of each line segment is obtained; Determining the operating characteristics of the corresponding line section according to the line loss data; Determining an operation status analysis method of each line segment based on the operating characteristics of the line segment, wherein the operation status analysis method includes a threshold warning method and an outlier detection method; Using the corresponding operating status analysis method to conduct comprehensive operating status monitoring on each line section of the distribution network; The line loss data includes a line loss rate, a line loss change rate, and a line loss offset; and obtaining the line loss data of each line segment includes: Acquiring electrical parameters of the line section based on a monitoring period; According to the electrical parameters of each line section, the supplied electric energy at the starting point of the line section and the output electric energy at the end point of the line section are calculated to obtain the line loss rate of each line section; A line loss variation curve is drawn according to the line loss rate of different monitoring periods, wherein the slope of the line loss variation curve represents the line loss variation rate; The line loss variation curve is overlapped and compared with a preset line loss curve and a no-load loss curve to obtain a line loss offset; Determining the operating condition characteristics of the corresponding line section according to the line loss data includes: Acquiring the cable status based on cable temperature monitoring, analyzing the abnormality of the line loss based on the line loss rate, analyzing the operation disturbance based on the line loss change rate, and analyzing the abnormality of the load based on the line loss offset; Determining the operating characteristics of the corresponding line section based on the cable status, the abnormal line loss, the operation disturbance, and the abnormal load; including: When the abnormal line loss condition is an increase in line loss and the operating disturbance condition is a non-periodic sudden increase, the operating condition characteristic of the line section is determined to be a transient instability condition; When the abnormal line loss condition is an increase in line loss, the abnormal load condition is an excessive load, and the cable state condition has a continuous high temperature, the operating condition characteristic of the line section is determined to be an overload operating condition; When the abnormal line loss condition is an increase in line loss, the abnormal load condition is an insufficient load, and the cable status condition has a local hot spot, the operating condition characteristic of the line section is determined to be a no-load operating condition; When the cable status is abnormal and does not meet the operating characteristics of the transient instability condition, the overload operating condition, and the no-load operating condition, the operating characteristics of the line section are determined to be abnormal cable conditions.

2. The method for comprehensive monitoring of the operation status of a distribution network according to claim 1, characterized in that: The method for analyzing the operating status of each line segment based on the operating characteristics of the line segment includes: When the operating condition characteristic of the line section is the transient instability condition, an alarm is issued for the operating status of the line section based on the correlation between the electrical parameters of the line section; When the operating condition of the line section is characterized by the overload operating condition or the no-load operating condition, a threshold warning method is used to analyze the operating state of the line section, and different threshold boundaries are set according to the importance of each monitoring indicator under different operating condition characteristics; When the operating condition of the line segment is characterized by the abnormal cable operating condition, the operating status of the line segment is analyzed by using an outlier detection method based on the characteristics of the neighborhood points of each monitoring point on the line segment.

3. The method for comprehensive monitoring of the operation status of a distribution network according to claim 2, characterized in that: When the operating condition characteristic of the line section is the transient instability operating condition, providing an alarm prompt for the operating status of the line section based on the correlation between the electrical parameters of the line section includes: Analyze the parameter correlation between the real-time voltage and current of the line section; If the parameter correlation is negative, a short circuit fault alarm is issued. If the parameter correlation is positive, a voltage compensation alarm is issued.

4. The method for comprehensive monitoring of the operation status of a distribution network according to claim 2, characterized in that: When the operating condition of the line section is characterized by the overload operating condition or the no-load operating condition, the operating state of the line section is analyzed by using a threshold warning method, and different threshold boundaries are set according to the importance of each monitoring indicator under different operating condition characteristics, including: Calculate the correlation between each monitoring indicator and the corresponding working condition characteristic quantity and sort them from large to small; Select the first k monitoring indicators, normalize the correlation of these monitoring indicators as importance weights to obtain comprehensive monitoring indicators, where k is a preset parameter; The threshold boundary of the comprehensive monitoring indicator is set based on the maximum value of the historical data of the comprehensive monitoring indicator under the normal operating state of the line section.

5. The method for comprehensive monitoring of the operation status of a distribution network according to claim 4, characterized in that: When the operating condition characteristic of the line section is the overload operating condition, the operating condition characteristic quantity is selected as the cable temperature; When the operating condition characteristic of the line section is the no-load operating condition, the operating condition characteristic quantity selects the power factor.

6. The method for comprehensive monitoring of the operation status of a distribution network according to claim 2, characterized in that: When the working condition characteristic of the line segment is the abnormal working condition of the cable, analyzing the operating state of the line segment by using an outlier detection method based on the characteristics of the neighborhood points of each monitoring point on the line segment includes: Obtain the spatial neighboring points and temporal neighboring points of the monitoring point to form a neighborhood set; Calculate the distance between the monitoring point and each point in its neighborhood set under each monitoring indicator and sum them up; The average value of the distance and the distance is used as the kernel function bandwidth and the kernel density estimation method is used to calculate the local density of the monitoring point to obtain the possibility that the monitoring point belongs to an outlier. Locate the location of cable anomalies based on outliers in the line segment.

7. A comprehensive monitoring system for the operation status of a distribution network, characterized in that: include: A data acquisition module, used to divide the distribution network into multiple line segments based on the location information of the monitoring node, and obtain the line loss data of each line segment; A working condition analysis module, used to determine working condition characteristics of a corresponding line section according to the line loss data; A strategy selection module, used to determine an operation status analysis mode of each line segment based on the operating characteristics of the line segment, wherein the operation status analysis mode includes a threshold warning mode and an outlier detection mode; An operation monitoring module, used for performing comprehensive operation status monitoring on each line segment of the distribution network by using the corresponding operation status analysis method; The line loss data includes a line loss rate, a line loss change rate, and a line loss offset; and obtaining the line loss data of each line segment includes: Acquiring electrical parameters of the line section based on a monitoring period; According to the electrical parameters of each line section, the supplied electric energy at the starting point of the line section and the output electric energy at the end point of the line section are calculated to obtain the line loss rate of each line section; A line loss variation curve is drawn according to the line loss rate of different monitoring periods, wherein the slope of the line loss variation curve represents the line loss variation rate; The line loss variation curve is overlapped and compared with a preset line loss curve and a no-load loss curve to obtain a line loss offset; Determining the operating condition characteristics of the corresponding line section according to the line loss data includes: Acquiring the cable status based on cable temperature monitoring, analyzing the abnormality of the line loss based on the line loss rate, analyzing the operation disturbance based on the line loss change rate, and analyzing the abnormality of the load based on the line loss offset; Determining the operating characteristics of the corresponding line section based on the cable status, the abnormal line loss, the operation disturbance, and the abnormal load; including: When the abnormal line loss condition is an increase in line loss and the operating disturbance condition is a non-periodic sudden increase, the operating condition characteristic of the line section is determined to be a transient instability condition; When the abnormal line loss condition is an increase in line loss, the abnormal load condition is an excessive load, and the cable state condition has a continuous high temperature, the operating condition characteristic of the line section is determined to be an overload operating condition; When the abnormal line loss condition is an increase in line loss, the abnormal load condition is an insufficient load, and the cable status condition has a local hot spot, the operating condition characteristic of the line section is determined to be a no-load operating condition; When the cable status is abnormal and does not meet the operating characteristics of the transient instability condition, the overload operating condition, and the no-load operating condition, the operating characteristics of the line section are determined to be abnormal cable conditions.

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