CN118150949A

CN118150949A - Power cable insulation layer temperature and insulation failure evaluation method

Info

Publication number: CN118150949A
Application number: CN202410159339.XA
Authority: CN
Inventors: 马智; 何真依; 商艳敏; 王楠; 王晶
Original assignee: Inner Mongolia Power Transmission And Distribution Co ltd
Current assignee: Inner Mongolia Power Transmission And Distribution Co ltd
Priority date: 2024-02-04
Filing date: 2024-02-04
Publication date: 2024-06-07

Abstract

The application relates to the field of cable monitoring, in particular to an evaluation method for the temperature and insulation failure of an insulating layer of a power cable. The method comprises the following steps: acquiring the current cable surface temperature distribution of the whole power line, wherein the power line comprises at least two sections of power cables, and the current cable surface temperature distribution comprises the current cable surface temperature corresponding to each position of the power line; acquiring the respective corresponding historical cable internal temperature of each position of each section of power cable; judging whether an insulation abnormal position exists in a cable of the power circuit according to the current cable surface temperature distribution of the power circuit and the historical cable internal temperature corresponding to each position; and when the insulation abnormal position exists, feeding the insulation abnormal position back to the terminal equipment of the staff. The application has the effect of improving the reliability of cable insulation failure detection.

Description

Power cable insulation layer temperature and insulation failure evaluation method

Technical Field

The application relates to the field of cable monitoring, in particular to an evaluation method for the temperature and insulation failure of an insulating layer of a power cable.

Background

In an electric power system, cables are used for connecting electric devices such as a generator, a transformer, a transmission line and the like to realize transmission and distribution of electric energy, for example, in Dengkou photovoltaic engineering, the cables are required to be used for connecting devices such as a photovoltaic panel, an inverter, a transformer and the like, so that electric energy generated by utilizing photovoltaic is transmitted to the inverter, and then the electric energy is transmitted to a power grid through the transformer. Therefore, the cable is a key device for power transmission, and the safe and stable operation of the cable is critical to the reliability of the whole power system. However, during long-term operation of the cable, the insulation layer may fail due to various factors, resulting in interruption of power transmission or damage to the equipment. Therefore, timely discovery and prevention of failure problems of cable insulation is one of the key tasks of power systems.

The insulation failure of the cable at the present stage is often evaluated by finding out at the time of periodic inspection or maintenance, and at the time of periodic inspection, a worker selects a part of the cable to detect the dielectric constant or insulation resistance value of the cable, etc., to evaluate the degree of insulation failure of the cable, so that the cable can be found out and adjusted at the time of insulation layer failure.

However, the potential insulation problem cannot be found in time by a periodic inspection mode, adjustment is difficult to be performed in time when the cable insulation is abnormal, and the reliability is low.

Disclosure of Invention

In order to improve reliability of cable insulation failure detection, the application provides a power cable insulation layer temperature and insulation failure evaluation method.

In a first aspect, the present application provides a method for evaluating a temperature and an insulation failure of an insulation layer of a power cable, which adopts the following technical scheme:

a method of evaluating a power cable insulation layer temperature and insulation failure, the method comprising:

Acquiring current cable surface temperature distribution of the whole power line, wherein the power line comprises at least two sections of power cables, and the current cable surface temperature distribution comprises current cable surface temperatures corresponding to each position of the power line;

Acquiring the respective corresponding historical cable internal temperature of each position of each section of power cable;

Judging whether an insulation abnormal position exists in a cable of the power circuit according to the current cable surface temperature distribution of the power circuit and the respective corresponding historical cable internal temperature of each position;

and when the abnormal insulation position exists, feeding the abnormal insulation position back to the terminal equipment of the staff.

Through adopting above-mentioned technical scheme, through the current cable surface temperature of the cable of each position in the real-time detection power line, and the inside temperature of history cable, whether there is the position of insulating layer insulation abnormality in the cable of each position in the judgement power line, whether there is the position of insulating layer insulation failure promptly, if there is, feedback the position of insulating abnormality to staff's terminal equipment, so that the staff can look for according to the position of insulating abnormality in the terminal equipment, thereby can in time discover the position of insulating layer insulation failure in the cable, and in time adjust when insulation failure, thereby the reliability of insulation failure detection has been improved, also be favorable to improving power transmission system's reliability.

In one possible implementation manner, preset positions are corresponding to the power lines, and each preset position is provided with a cable internal temperature detection device, and the cable internal temperature detection device is used for detecting the cable internal temperature of the preset position;

Wherein, according to the current cable surface temperature distribution of the power circuit and the historical cable internal temperature corresponding to each position, judging whether there is an abnormal insulation position in the cable of the power circuit, including:

Judging whether surface abnormal positions exist in each section of power cable according to the current cable surface temperature corresponding to each position of each section of power cable, wherein the surface temperature of each surface abnormal position is higher than a preset temperature threshold value compared with the surface temperature of other positions in each section of power cable;

determining the normal position of the surface in each section of power cable, wherein the normal position of the surface is a position which does not belong to the abnormal position of the surface in each section of power cable;

acquiring the current internal temperature of the cable at each preset position;

Determining the current cable internal temperature corresponding to each surface normal position according to the current cable internal temperature of each preset position and the surface normal position in each section of power cable;

determining whether abnormal temperature change positions exist in the normal positions of the surfaces according to the current cable internal temperatures corresponding to the normal positions of the surfaces and the historical cable internal temperatures corresponding to the normal positions of the surfaces;

Judging whether the cable has an insulation abnormal position according to whether each position of the cable belongs to a surface abnormal position or a temperature change abnormal position.

In another possible implementation manner, the determining whether the surface abnormal position exists in each section of the power cable according to the current cable surface temperature corresponding to each position of each section of the power cable includes:

acquiring the ambient temperature of each section of power cable;

Dividing each section of power cable according to the environmental temperature, and dividing the power cable with the environmental temperature belonging to the same preset temperature interval into a power cable interval;

For each power cable section, comparing the current cable surface temperature of each position of each power cable section, and judging whether positions with the current cable surface temperature higher than other current cable surface temperatures by a preset threshold value exist or not;

And judging whether the surface abnormal position exists in each section of power cable according to the judging result corresponding to each power cable section.

In another possible implementation manner, the determining, according to the current cable internal temperature of each preset position and the surface normal position in each section of power cable, the current cable internal temperature corresponding to each surface normal position includes:

Acquiring the power transmission quantity of each section of power cable and the power transmission quantity corresponding to each preset position;

determining the preset positions corresponding to the normal positions of the surfaces of the power cables;

Determining conversion proportion corresponding to each preset position according to the current cable internal temperature corresponding to each preset position and the current cable surface temperature corresponding to each preset position;

And determining the current cable internal temperature corresponding to each surface normal position according to the current cable surface temperature corresponding to each surface normal position and the conversion proportion of the preset position corresponding to each surface normal position.

In another possible implementation manner, determining the preset position corresponding to the surface normal position of each section of the power cable includes:

determining a preset position which is the same as the power transmission amount of the normal position of the surface according to the power transmission amount;

And selecting a preset position nearest to the surface normal position from the preset positions with the same power transmission quantity as the surface normal position, and determining the preset position as the preset position corresponding to the surface normal position.

In another possible implementation manner, the determining whether the abnormal position of the temperature change exists in the normal positions of the surfaces according to the respective corresponding current cable internal temperature and the respective corresponding historical cable internal temperature of the normal positions of the surfaces includes:

Determining the high-temperature duration time corresponding to each normal position of each surface according to the current cable internal temperature and the historical cable internal temperature, wherein the high-temperature duration time is the sum of time durations of the temperature exceeding a preset temperature threshold value;

Determining the temperature change amplitude corresponding to the normal position of each surface, wherein the temperature change amplitude is used for representing the difference between the highest temperature and the lowest temperature;

Judging whether the high-temperature duration time corresponding to each normal position of each surface exceeds a preset duration time;

judging whether the temperature change amplitude corresponding to each normal position of each surface exceeds a preset amplitude;

If the high-temperature duration corresponding to the normal position of any surface exceeds the preset duration and/or the corresponding temperature change amplitude exceeds the preset threshold, determining that the abnormal position of the temperature change exists in the normal position of the surface, wherein the normal position of any surface is the abnormal position of the temperature change.

In a second aspect, the application provides an evaluation device for temperature and insulation failure of an insulating layer of a power cable, which adopts the following technical scheme:

an apparatus for evaluating temperature and insulation failure of an insulation layer of a power cable, the apparatus comprising:

the surface temperature acquisition module is used for acquiring the current cable surface temperature distribution of the whole power line, wherein the power line comprises at least two sections of power cables, and the current cable surface temperature distribution comprises the current cable surface temperature corresponding to each position of the power line;

The internal temperature acquisition module is used for acquiring the internal temperatures of the historical cables corresponding to the positions of each section of power cable;

The insulation abnormality determining module is used for judging whether an insulation abnormality position exists in a cable of the power circuit according to the current cable surface temperature distribution of the power circuit and the respective corresponding historical cable internal temperatures of all the positions;

and the abnormal feedback module is used for feeding back the abnormal insulation position to the terminal equipment of the staff when the abnormal insulation position exists.

The insulation abnormality determination module is specifically configured to, when determining whether an insulation abnormality position exists in a cable of the power circuit according to a current cable surface temperature distribution of the power circuit and a historical cable internal temperature corresponding to each position, determine that the insulation abnormality position exists in the cable of the power circuit:

In another possible implementation manner, the insulation abnormality determining module is specifically configured to, when determining whether a surface abnormality position exists in each section of power cable according to a current cable surface temperature corresponding to each position of each section of power cable:

acquiring the ambient temperature of each section of power cable;

In another possible implementation manner, the insulation abnormality determining module is specifically configured to, when determining the current cable internal temperature corresponding to each surface normal position according to the current cable internal temperature of each preset position and the surface normal position in each section of power cable:

In another possible implementation manner, the insulation abnormality determining module is specifically configured to, when determining the preset positions corresponding to the normal positions of the surface of each section of the power cable:

In another possible implementation manner, the insulation anomaly determination module is specifically configured to, when determining whether there is an abnormal temperature change position in each surface normal position according to the current cable internal temperature corresponding to each surface normal position and the historical cable internal temperature corresponding to each surface normal position:

In a third aspect, the present application provides an electronic device, which adopts the following technical scheme:

An electronic device, the electronic device comprising:

At least one processor;

a memory;

At least one application program, wherein the at least one application program is stored in the memory and configured to be executed by the at least one processor, the at least one application program configured to: and executing the method for evaluating the temperature of the insulating layer and the insulation failure of the power cable.

In a fourth aspect, the present application provides a computer readable storage medium, which adopts the following technical scheme:

A computer-readable storage medium, comprising: a computer program is stored that can be loaded by a processor and that performs the above-described method of evaluating the temperature and insulation failure of a power cable insulation layer.

In summary, the application has the following beneficial technical effects:

The current cable surface temperature of the cable at each position in the power line and the historical cable internal temperature are detected in real time to judge whether the position of insulation abnormality of the insulation layer exists in the cable at each position in the power line, namely whether the position of insulation failure of the insulation layer exists, if the position exists, the insulation abnormality position is fed back to the terminal equipment of the staff, so that the staff can search according to the insulation abnormality position in the terminal equipment, the position of insulation failure of the insulation layer in the cable can be timely found, and the position can be timely adjusted when the insulation failure exists, so that the reliability of insulation failure detection is improved, and the reliability of a power transmission system is also facilitated to be improved.

Drawings

FIG. 1 is a flow chart of a method for evaluating temperature and insulation failure of an insulation layer of a power cable according to an embodiment of the application;

FIG. 2 is a schematic block diagram of an apparatus for evaluating temperature and insulation failure of an insulation layer of a power cable according to an embodiment of the application;

fig. 3 is a schematic diagram of an electronic device according to an embodiment of the application.

Detailed Description

The application is described in further detail below with reference to fig. 1-3.

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present application more apparent, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments of the present application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

The embodiment of the application provides a method for evaluating the temperature and insulation failure of an insulating layer of a power cable, which is executed by electronic equipment, wherein as shown in fig. 1, the method comprises the following steps:

Step S101, acquiring the current cable surface temperature distribution of the whole power line.

The power line comprises at least two sections of power cables, and the current cable surface temperature distribution comprises the current cable surface temperature corresponding to each position of the power line.

Specifically, among the power lines, there are often included a plurality of pieces of power cables, for example, a power cable in a connection line between each photovoltaic panel and the inverter, a power cable connected between the inverter and the transformer, and the like.

When the insulation layer of the cable at a certain position in the power line fails in insulation, the position is characterized by local overheating, so that in order to evaluate the cable insulation failure of the whole power line, the temperature of the whole cable surface can be monitored in real time by using the thermal infrared imager to obtain the surface temperature distribution of the whole cable, so that the electronic equipment can acquire the current cable surface temperature distribution of the whole power line, and then whether the cable insulation failure at a part of positions exists can be judged according to the current cable surface temperature distribution of the whole power line.

Step S102, acquiring the respective corresponding historical cable internal temperatures of each position of each section of power cable.

The cable internal temperature is the temperature of the cable internal, and the temperature of the insulating layer of the cable can be directly reflected through the cable internal temperature because the insulating layer is positioned in the cable.

Specifically, if the cable runs at a high temperature for a long period of time, the aging and failure of the cable insulation layer are accelerated, so that the running condition of the cable insulation layer can be also estimated through the change of the temperature of the cable insulation layer so as to predict the possibility of failure. Accordingly, the respective historical cable interior temperatures of the cables at the respective locations may also be obtained so as to predict the life of the insulating layer of the cable based on the historical cable interior temperatures.

Step S103, judging whether an insulation abnormal position exists in the cable of the power circuit according to the current cable surface temperature distribution of the power circuit and the historical cable internal temperature corresponding to each position.

And step S104, feeding back the insulation abnormal position to the terminal equipment of the staff when the insulation abnormal position exists.

Specifically, according to the current cable surface temperature of the cable at each position in the power circuit, whether a local overheat phenomenon occurs can be judged, so that whether an insulation abnormal position exists in the cable of the current power circuit or not can be judged, and when the local overheat phenomenon occurs, the local overheat position is the insulation abnormal position. The loss of the insulation layer inside the cable can be predicted according to the respective corresponding historical cable inside temperature of each position in the power line, namely according to the temperature change of the insulation layer inside the cable of each position, so as to evaluate the failure condition of the insulation layer inside the cable, and when the insulation layer inside the cable possibly fails, the insulation abnormal position is characterized, namely the insulation abnormal position is the position where the insulation layer of the cable possibly fails. And then feeding back the insulation abnormal position to the terminal equipment of the staff, so that the staff can check and search according to the insulation abnormal position displayed in the terminal equipment, the internal and external temperatures of the cable can be detected in real time, and whether the cable has the insulation abnormal position or not can be timely found, so that timely adjustment can be timely found when insulation layer insulation fails, the reliability of cable insulation failure detection is improved, and the reliability of the power transmission system is also improved.

The embodiment of the application provides an evaluation method for insulation layer temperature and insulation failure of a power cable, which is characterized in that the current cable surface temperature and the historical cable internal temperature of the cable at each position in a power line are detected in real time to judge whether the position of insulation layer insulation abnormality exists in the cable at each position in the power line, namely whether the position of insulation layer insulation failure exists, if so, the insulation abnormality position is fed back to a staff terminal device, so that the staff can search according to the insulation abnormality position in the terminal device, the insulation failure position of the cable can be found in time, and the insulation failure detection reliability is improved, and the reliability of a power transmission system is also improved.

In one possible implementation manner of the embodiment of the present application, preset positions are corresponding to the power lines, and each preset position is provided with a cable internal temperature detection device, where the cable internal temperature detection device is used for detecting the cable internal temperature of the preset position. The cable internal temperature detection device can be specifically an optical fiber, and the optical fiber is installed in the cable, so that the temperature in the cable can be measured by utilizing the optical fiber to obtain the temperature in the cable at a corresponding position.

In step S103, according to the current cable surface temperature distribution of the power circuit and the respective historical cable internal temperatures corresponding to the respective positions, it is determined whether an insulation abnormality position exists in the cable of the power circuit, which may be specifically implemented by the following steps:

step S1031 (not shown in the figure) determines whether or not there is a surface abnormality position in each section of the power cable according to the current cable surface temperature corresponding to each position of each section of the power cable.

Wherein the surface temperature at the surface anomaly location is above a preset temperature threshold as compared to the surface temperature at other locations in each segment of the cable.

Specifically, when the surface temperature of the cable at a certain position in the power cable has a larger difference from the surface temperatures of the cables at other positions, and the surface temperature of the cable at the certain position is higher than the surface temperature of the cable at other positions, the surface temperature of the cable at the certain position is abnormal, and a local overheating phenomenon occurs, and at the moment, the position is the surface abnormal position. For example: when the temperature of most of the positions in the power cable is about 20 ℃, the temperature of the position A is 40 ℃, and the temperature of the characterization position A is higher than the surface temperature of other positions by a preset temperature threshold, namely the position A is a surface abnormal position.

More specifically, according to the current cable surface temperature corresponding to each position, the method for searching the surface abnormal position specifically includes: and calculating the average value of the surface temperatures of all the current cables, and then calculating the deviation between the surface temperatures of the current cables corresponding to all the positions and the average value, wherein the deviation is larger than the position of a preset deviation value, and the position is the surface abnormal position.

Step S1032 (not shown), determining the surface normal position in each section of the power cable.

The normal position of the surface is a position which does not belong to the abnormal position of the surface in each section of power cable.

Specifically, the normal surface position is a position which does not belong to an abnormal surface position in the power cable, namely, the difference value between the current cable surface temperature of the normal surface position and the current cable surface temperature of other positions is smaller than a preset temperature threshold value.

Step S1033 (not shown in the drawing) acquires the current cable internal temperature at each preset position.

Step S1034 (not shown in the figure), determining the respective current cable internal temperature corresponding to each surface normal position according to the current cable internal temperature of each preset position and the surface normal position in each section of power cable.

Specifically, when determining whether the insulation abnormal position exists in each section of the power cable, the insulation abnormal position can be determined through the change condition of the internal temperature in the power cable, specifically, the current cable internal temperature corresponding to each normal position of each surface can be calculated, and then the change condition of the internal temperature corresponding to each normal position of each surface in the power cable can be determined according to the current cable internal temperature and the historical cable internal temperature.

More specifically, in step S1034, the manner of determining the current cable internal temperature corresponding to each surface normal position according to the current cable internal temperature of each preset position and the surface normal position in each section of power cable may be specifically implemented by the following steps:

step Sa1 (not shown), acquiring the power transmission amount of each power cable and the power transmission amount corresponding to each preset position.

Step Sa2 (not shown in the figure) determines a preset position corresponding to the normal position of the surface of each power cable.

Step Sa3 (not shown in the figure) determines the conversion ratio corresponding to each preset position according to the current cable internal temperature corresponding to each preset position and the current cable surface temperature corresponding to each preset position.

Step Sa4 (not shown in the figure), determining the current cable internal temperature corresponding to each surface normal position according to the current cable surface temperature corresponding to each surface normal position and the conversion ratio of the preset position corresponding to each surface normal position.

Specifically, in order to calculate the current cable internal temperature corresponding to each surface normal position, a conversion ratio of the internal temperature to the external temperature can be calculated according to the current cable internal temperature and the current cable external temperature at the preset position, and then the current cable internal temperature corresponding to each surface normal position can be determined by combining the current cable surface temperature corresponding to each surface normal position according to the conversion ratio. However, the internal and external temperatures of the cables corresponding to different power transmission amounts are different, so that the respective corresponding preset positions of the normal positions of the surfaces can be determined, and then when the current internal temperature of the cable is determined according to the conversion ratio, the current internal temperature of the cable can be calculated according to the conversion ratio of the respective corresponding preset positions.

More specifically, the power transmission amount per preset position, which may be specifically electric energy transmitted per unit time, and the power transmission amount per normal position of the surface are acquired. And then determining the preset position with the same power transmission quantity as the normal position of the surface as the preset position corresponding to the normal position of the surface.

Further, since the surface temperature of the cable is also in a certain relationship with the environment, for example, when the internal temperature of the cable is the same, the surface temperature of the cable in the outdoor environment at 20 degrees celsius is not the same as the surface temperature of the cable in the outdoor environment at 0 degrees celsius, that is, the conversion ratio of the internal temperature of the cable to the surface temperature of the cable is also related to the outdoor environment, when determining the preset position corresponding to the normal position of the surface, the method specifically may include: determining a preset position which is the same as the power transmission amount of the normal position of the surface according to the power transmission amount; from among the preset positions having the same power transmission amount as the surface normal position, the preset position closest to the surface normal position is selected, and is determined as the preset position corresponding to the surface normal position.

Specifically, from among preset positions having the same power transmission amount, a preset position closest to the normal position of the surface is selected, and the outdoor environments where the two positions are located are the same the closer to the normal position of the surface, so that the preset position closest to the normal position of the surface is selected as the preset position corresponding to the normal position of the surface, and the power transmission amount of the preset position is the same as that of the normal position of the surface, so that the current cable internal temperature of the normal position of the surface can be determined more accurately according to the conversion ratio of the preset position.

It should be noted that, since the surface abnormal position may have failed in insulation, there may be a large error in calculating the current cable internal temperature by the conversion ratio of the internal temperature and the surface temperature at the preset position, because the insulation layer fails, the conversion ratio of the internal temperature and the external temperature may be different from the conversion ratio at the preset position, and the cable internal temperature at the position where the insulation layer fails is calculated according to the conversion ratio at the preset position, which may have a large error, and there is no need to recalculate the current cable internal temperature for the surface abnormal position.

It should be noted that, when the current cable internal temperature of each location is determined, the current cable internal temperature of each location is stored in the history database and is stored as the history cable internal temperature, so that when the history cable internal temperature is obtained in step S102, the current cable internal temperature of each location can be obtained from the history database.

Step S1035 (not shown in the drawing) determines whether or not there is an abnormal position of temperature change in each surface normal position based on the current cable internal temperature corresponding to each surface normal position and the historical cable internal temperature corresponding to each surface normal position.

Step S1036 (not shown in the figure) determines whether or not there is an insulation abnormality position of the cable according to whether or not each position of the cable belongs to a surface abnormality position or belongs to a position of a temperature change abnormality.

Specifically, for a position where there is no local overheat, that is, for a surface normal position, the insulation of the insulation layer thereof may also approach failure, and therefore, for the surface normal position, it is predicted whether there is a variation abnormality in the temperature of the cable corresponding to the surface normal position, that is, whether the insulation of the cable at the surface normal position fails, that is, whether there is a temperature variation abnormality in each surface normal position, based on the current cable internal temperature and the historical cable internal temperature of the surface normal position. And when the surface abnormal position exists in each position and/or when the temperature change abnormal position exists in the surface normal position, the cable is characterized to exist in an insulation abnormal position, and the surface abnormal position and/or the temperature change abnormal position is the insulation abnormal position.

More specifically, in step S1035, determining whether there is an abnormal position of temperature change in each surface normal position according to the current cable internal temperature corresponding to each surface normal position and the historical cable internal temperature corresponding to each surface normal position may specifically include:

According to the current cable internal temperature and the historical cable internal temperature, determining the high-temperature duration time corresponding to each normal position of each surface, wherein the high-temperature duration time is the sum of time durations of the temperature exceeding a preset temperature threshold, for example: in the history of the surface normal position B1, the total duration of time when the internal temperature of the cable exceeds a preset temperature threshold value is 1h, and the duration of high temperature corresponding to the surface normal position B1 is 1h; determining a temperature change amplitude corresponding to each surface normal position, wherein the temperature change amplitude is used for representing a difference value between the highest temperature and the lowest temperature, for example, the temperature in a cable at the surface normal position B1 is 15 ℃ at the minimum and 80 ℃ at the maximum, and the temperature change amplitude is 65 ℃; judging whether the high-temperature duration time corresponding to each normal position of each surface exceeds a preset duration time; judging whether the temperature change amplitude corresponding to each normal position of each surface exceeds a preset amplitude; if the high-temperature duration corresponding to the normal position of any surface exceeds the preset duration and/or the corresponding temperature change amplitude exceeds the preset threshold, determining that the abnormal position of the temperature change exists in the normal position of the surface, and the normal position of any surface is the abnormal position of the temperature change.

Specifically, the operation temperature of the cable is one of the important factors influencing the service life of the insulating layer, and if the temperature of the cable is higher or fluctuates greatly for a long time, the ageing and failure risks of the insulating layer are increased, namely the risk of insulating failure is high, and detection is needed. Therefore, the high-temperature duration time corresponding to each normal position of each surface is calculated, when the high-temperature duration time exceeds the preset duration time, the risk of insulation failure of the normal position of the surface is high, and at the moment, the normal position of the surface with the high-temperature duration time exceeding the preset duration time is determined to be the abnormal position of temperature change. And calculating the temperature change amplitude value corresponding to each normal position of each surface, if the temperature change amplitude value exceeds the preset amplitude value, representing that the temperature fluctuation of the cable is large, representing that the risk of insulation failure of the normal position of the surface with the temperature change amplitude value exceeding the preset amplitude value is large, and determining the normal position of the surface as an abnormal position of the temperature change.

More specifically, when, among the respective surface normal positions, there is any surface normal position for which the high temperature duration exceeds the preset duration, and/or there is any surface normal position for which the temperature change amplitude exceeds the preset amplitude, that is, it is indicated that there is a temperature change abnormal position, for example: the high-temperature duration of the surface normal position B2 exceeds the preset duration, the temperature change amplitude of the surface normal position B2 does not exceed the preset amplitude, the high-temperature duration of the surface normal position B3 exceeds the preset duration, the temperature change amplitude of the surface normal position B3 exceeds the preset amplitude, the existence of the temperature change abnormal position is indicated, and the surface normal position B2 and the surface normal position B3 are both temperature change abnormal positions.

In a possible implementation manner of the embodiment of the present application, in the step S1031, when determining whether a surface abnormality position exists in each section of power cable according to the current cable surface temperature corresponding to each position of each section of power cable, in one implementation manner, a position where the current cable surface temperature is higher than the preset threshold value of the surface temperatures of other current cables in each section of power cable may be directly searched according to each section of power cable, where the position is the surface abnormality position. In another implementation, since the power cables are longer, the different power cables are at different environmental temperatures, for example, part of the power cables are at a temperature of 5 degrees celsius, part of the power cables are at an environmental temperature of-2 degrees celsius, and the temperature of the outer surface of the power cables is also affected by the environmental temperature, in order to improve accuracy when determining the abnormal position of the surface, it is also possible to implement the following method: acquiring the ambient temperature of each section of power cable; dividing each section of power cable according to the ambient temperature, and dividing the power cable with the ambient temperature in the same preset temperature interval into a power cable interval; for each power cable section, comparing the current cable surface temperature of each position of each power cable section, and judging whether positions with the current cable surface temperature higher than other current cable surface temperatures by a preset threshold value exist or not; and judging whether the surface abnormal position exists in each section of power cable according to the judging result corresponding to each power cable section.

Specifically, each section of power cable is divided according to the ambient temperature, and the power cables with the ambient temperature in the same preset temperature interval are divided into one power cable interval, wherein the ambient temperature can be obtained from a weather bureau or obtained by measuring by using an ambient temperature measuring device, and the embodiment of the application is not limited. In addition, the preset temperature interval is preset, for example, the temperature range from-10 ℃ to-7 ℃ is divided into a preset temperature interval. After the power cables are divided according to the environment temperature, the environment temperature of the power cables in one power cable section is the same, so that the current cable surface temperatures of all the positions in the same power cable section can be directly compared at the moment to judge whether the current cable surface temperature is higher than the surface temperatures of other current cables and higher than a preset threshold value, and the position is the surface abnormal position.

More specifically, when dividing the power cable sections, for example, for a section of power cable from the photovoltaic panel to the inverter, if the distance from the photovoltaic panel is taken as the horizontal axis, the power cable corresponds to a line section, the power cable sections are divided from the photovoltaic panel, and if the environmental temperature in the range of 10m from the photovoltaic panel is 8-10 ℃ and is in the same preset temperature section, the power cable in the range of 10m from the photovoltaic panel is divided into one power cable section.

The foregoing embodiments describe a method for evaluating a temperature and an insulation failure of an insulation layer of a power cable from a method flow, and the following embodiments describe an apparatus for evaluating a temperature and an insulation failure of an insulation layer of a power cable from a virtual module or a virtual unit, which are described in detail in the following embodiments.

Referring to fig. 2, an apparatus 200 for evaluating a temperature and insulation failure of an insulation layer of a power cable, the apparatus comprising:

A surface temperature acquisition module 201, configured to acquire a current cable surface temperature distribution of an entire power line, where the power line includes at least two sections of power cables, and the current cable surface temperature distribution includes a current cable surface temperature corresponding to each position of the power line;

An internal temperature obtaining module 202, configured to obtain an internal temperature of the historical cable corresponding to each position of each section of the power cable;

An insulation abnormality determining module 203, configured to determine whether an insulation abnormality position exists in a cable of the power circuit according to a current cable surface temperature distribution of the power circuit and a historical cable internal temperature corresponding to each position;

and the abnormality feedback module 204 is used for feeding back the insulation abnormal position to the staff terminal equipment when the insulation abnormal position exists.

In one possible implementation manner of the embodiment of the application, preset positions are corresponding to the power lines, and each preset position is provided with a cable internal temperature detection device which is used for detecting the cable internal temperature of the preset position;

The insulation abnormality determination module 203 is specifically configured to, when determining whether an insulation abnormality position exists in a cable of the power circuit according to a current cable surface temperature distribution of the power circuit and a historical cable internal temperature corresponding to each position,:

Judging whether surface abnormal positions exist in each section of power cable according to the current cable surface temperature corresponding to each position of each section of power cable, wherein the surface temperature of the surface abnormal positions is higher than a preset temperature threshold value compared with the surface temperature of other positions in each section of power cable;

And judging whether the cable has an insulation abnormal position according to whether each position of the cable belongs to a surface abnormal position or a temperature change abnormal position.

In one possible implementation manner of the embodiment of the present application, when the insulation anomaly determination module 203 determines, according to the current cable surface temperature corresponding to each position of each section of power cable, whether there is a surface anomaly position in each section of power cable, the insulation anomaly determination module is specifically configured to:

Acquiring the ambient temperature of each section of power cable;

Dividing each section of power cable according to the ambient temperature, and dividing the power cable with the ambient temperature belonging to the same preset temperature interval into a power cable interval;

In one possible implementation manner of the embodiment of the present application, when the insulation anomaly determination module 203 determines the current cable internal temperature corresponding to each surface normal position according to the current cable internal temperature of each preset position and the surface normal position in each section of power cable, the insulation anomaly determination module is specifically configured to:

Determining the corresponding preset positions of the normal positions of the surfaces of each section of power cable;

And determining the current cable internal temperature corresponding to the normal position of each surface according to the current cable surface temperature corresponding to the normal position of each surface and the conversion proportion of the preset position corresponding to the normal position of each surface.

In one possible implementation manner of the embodiment of the present application, when determining the preset positions corresponding to the normal positions of the surface of each section of the power cable, the insulation abnormality determining module 203 is specifically configured to:

from among the preset positions having the same power transmission amount as the surface normal position, the preset position closest to the surface normal position is selected, and is determined as the preset position corresponding to the surface normal position.

In one possible implementation manner of the embodiment of the present application, when determining whether there is an abnormal temperature change position in each normal surface position according to the current cable internal temperature corresponding to each normal surface position and the historical cable internal temperature corresponding to each normal surface position, the insulation abnormality determining module 203 is specifically configured to:

determining the high-temperature duration time corresponding to each normal position of each surface according to the current cable internal temperature and the historical cable internal temperature, wherein the high-temperature duration time is the sum of time durations of the temperatures exceeding a preset temperature threshold;

If the high-temperature duration corresponding to the normal position of any surface exceeds the preset duration and/or the corresponding temperature change amplitude exceeds the preset threshold, determining that the abnormal position of the temperature change exists in the normal position of the surface, and the normal position of any surface is the abnormal position of the temperature change.

It will be clear to those skilled in the art that, for convenience and brevity of description, specific working procedures of the above-described systems, apparatuses and units may refer to corresponding procedures in the foregoing method embodiments, and are not repeated herein.

The embodiment of the application also describes an electronic device from the perspective of the entity apparatus, as shown in fig. 3, the electronic device 300 shown in fig. 3 includes: a processor 301 and a memory 303. Wherein the processor 301 is coupled to the memory 303, such as via a bus 302. Optionally, the electronic device 300 may also include a transceiver 304. It should be noted that, in practical applications, the transceiver 304 is not limited to one, and the structure of the electronic device 300 is not limited to the embodiment of the present application.

The Processor 301 may be a CPU (Central Processing Unit ), general purpose Processor, DSP (DIGITAL SIGNAL Processor, data signal Processor), ASIC (Application SPECIFIC INTEGRATED Circuit), FPGA (Field Programmable GATE ARRAY ) or other programmable logic device, transistor logic device, hardware component, or any combination thereof. Which may implement or perform the various exemplary logic blocks, modules and circuits described in connection with this disclosure. Processor 301 may also be a combination that implements computing functionality, e.g., comprising one or more microprocessor combinations, a combination of a DSP and a microprocessor, etc.

Bus 302 may include a path to transfer information between the components. Bus 302 may be a PCI (PERIPHERAL COMPONENT INTERCONNECT, peripheral component interconnect standard) bus or an EISA (Extended Industry Standard Architecture ) bus, or the like. Bus 302 may be divided into an address bus, a data bus, a control bus, and the like. For ease of illustration, only one thick line is shown in fig. 3, but not only one bus or one type of bus.

The Memory 303 may be, but is not limited to, a ROM (Read Only Memory) or other type of static storage device that can store static information and instructions, a RAM (Random Access Memory ) or other type of dynamic storage device that can store information and instructions, an EEPROM (ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY ), a CD-ROM (Compact Disc Read Only Memory, compact disc Read Only Memory) or other optical disk storage, optical disk storage (including compact discs, laser discs, optical discs, digital versatile discs, blu-ray discs, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer.

The memory 303 is used for storing application program codes for executing the inventive arrangements and is controlled to be executed by the processor 301. The processor 301 is configured to execute the application code stored in the memory 303 to implement what is shown in the foregoing method embodiments.

Among them, electronic devices include, but are not limited to: mobile terminals such as mobile phones, notebook computers, digital broadcast receivers, PDAs (personal digital assistants), PADs (tablet computers), PMPs (portable multimedia players), car terminals (e.g., car navigation terminals), and stationary terminals such as digital TVs, desktop computers, and the like, and servers and the like. The electronic device shown in fig. 3 is only an example and should not be construed as limiting the functionality and scope of use of the embodiments of the application.

Embodiments of the present application provide a computer-readable storage medium having a computer program stored thereon, which when run on a computer, causes the computer to perform the corresponding method embodiments described above. In the embodiment of the application, the current cable surface temperature of the cable at each position in the power line and the historical cable internal temperature are detected in real time to judge whether the position of insulation abnormality of the insulation layer exists in the cable at each position in the power line, namely whether the position of insulation failure of the insulation layer exists, if the position of insulation abnormality exists, the position of insulation abnormality is fed back to the terminal equipment of the staff, so that the staff can search according to the position of insulation abnormality in the terminal equipment, the position of insulation failure of the insulation layer in the cable can be timely found, and the position of insulation failure can be timely adjusted when the insulation failure exists, thereby improving the reliability of insulation failure detection and being beneficial to improving the reliability of a power transmission system.

It should be understood that, although the steps in the flowcharts of the figures are shown in order as indicated by the arrows, these steps are not necessarily performed in order as indicated by the arrows. The steps are not strictly limited in order and may be performed in other orders, unless explicitly stated herein. Moreover, at least some of the steps in the flowcharts of the figures may include a plurality of sub-steps or stages that are not necessarily performed at the same time, but may be performed at different times, the order of their execution not necessarily being sequential, but may be performed in turn or alternately with other steps or at least a portion of the other steps or stages.

The foregoing is only a partial embodiment of the present application, and it should be noted that it will be apparent to those skilled in the art that modifications and adaptations can be made without departing from the principles of the present application, and such modifications and adaptations should and are intended to be comprehended within the scope of the present application.

Claims

1. A method for evaluating temperature and insulation failure of an insulating layer of a power cable, the method comprising:

2. The method according to claim 1, wherein preset positions are corresponding on the power line, each preset position being provided with a cable internal temperature detection device for detecting a cable internal temperature of the preset position;

3. The method according to claim 2, wherein the determining whether the surface abnormality exists in each section of the power cable according to the current cable surface temperature corresponding to each position of each section of the power cable, comprises:

acquiring the ambient temperature of each section of power cable;

4. The method according to claim 2, wherein determining the respective current cable internal temperature corresponding to the respective surface normal position according to the current cable internal temperature of each preset position and the surface normal position in each section of the power cable comprises:

5. The method of claim 4, wherein determining the respective predetermined position corresponding to the normal position of the surface of each section of the power cable comprises:

6. The method of claim 2, wherein determining whether there is an abnormal temperature change location in each of the surface normal locations based on the respective corresponding current cable interior temperature and the respective corresponding historical cable interior temperature for each of the surface normal locations comprises:

7. An apparatus for evaluating temperature and insulation failure of an insulating layer of a power cable, comprising:

8. The apparatus according to claim 7, wherein preset positions are corresponding on the power line, each preset position being provided with a cable internal temperature detection means for detecting a cable internal temperature of the preset position;

9. An electronic device, comprising:

At least one processor;

a memory;

At least one application program, wherein the at least one application program is stored in the memory and configured to be executed by the at least one processor, the at least one application program configured to: the method for evaluating the temperature and insulation failure of the power cable insulation layer according to any one of claims 1 to 6 is performed.

10. A computer-readable storage medium, on which a computer program is stored, characterized in that the computer program, when executed in a computer, causes the computer to carry out the method of evaluating the insulation layer temperature and insulation failure of a power cable according to any one of claims 1 to 6.