A cable operation monitoring method based on Internet of Things

Abstract

The present invention relates to the technical field of cable operation monitoring, and discloses a cable operation monitoring method based on the Internet of Things. The present invention divides cables within a monitoring area into n sections, calculates a first insulation state coefficient of the cables in the n sections according to cable temperature data in the n sections, if an area with a first insulation state coefficient greater than or equal to a first insulation state coefficient threshold appears, it indicates that the insulation performance of the cables in this area is abnormal, divides the area with abnormal cable insulation performance into m sections, calculates a second insulation state coefficient of the m sections according to the discharge frequency of the m sections, compares the second insulation state coefficient of the m sections with a preset second insulation state coefficient threshold, determines a specific area with abnormal insulation performance of the entire cable, and finally estimates the remaining service life of the cable according to the first insulation state coefficient and the second insulation state coefficient.

Description

Technical Field

[0001] The present invention relates to the technical field of cable operation monitoring, and in particular to a cable operation monitoring method based on the Internet of Things. Background Art

[0002] With the rapid development of modern urban construction, the safe operation of power facilities has become particularly important. Cables are the main way to transmit electric energy over long distances. They are widely distributed, long distances, and have complex geographical environments, which poses a huge challenge to operation and maintenance management. The safe operation of cables is not only affected by equipment factors such as cable joint temperature, partial discharge, and circulating current, but also by external factors such as ambient temperature and humidity, harmful gases, fire, flooding, and theft of manhole covers.

[0003] The existing cable operation monitoring has the problem of insufficient comprehensiveness: when the cable is transmitted over long distances, the environment in each area is inconsistent, so the insulation performance loss of the cable is also inconsistent, and it is impossible to accurately determine the area where the cable insulation performance is abnormal. Therefore, the present invention proposes a cable operation monitoring method based on the Internet of Things. Summary of the invention

[0004] The purpose of the present invention is to provide a cable operation monitoring method based on the Internet of Things to solve the above-mentioned problems.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] A cable operation monitoring method based on the Internet of Things, the method comprising the following steps:

[0007] Step S1, divide the cables within the monitoring area into n sections, and number each section, the numbers are: 1, 2..., n;

[0008] Step S2, monitoring the cable temperature data of the n-segment area, and evaluating the insulation status according to the change of the temperature data;

[0009] Step S3, calculating the first insulation state coefficients of the cables in the n sections respectively according to the change of the cable temperature data in the n sections;

[0010] Step S4, comparing the first insulation state coefficient of the cable in the i-th section area with a preset first insulation state coefficient threshold value, if the first insulation state coefficient of the cable in the i-th section area is greater than or equal to the first insulation state coefficient threshold value, it means that the insulation performance of the cable in the i-th section area is abnormal, and proceeding to step S5, where i belongs to n;

[0011] Step S5, dividing the i-th area into m segments, and numbering each segment in the following order: 1, 2, ..., m;

[0012] Step S6, monitoring the cable discharge frequency in the m-segment area, and further evaluating the cable insulation status in the i-th segment area according to the change in the cable discharge frequency;

[0013] Step S7, calculating the second insulation state coefficients of the cables in the m-segment areas respectively according to the change of the cable discharge frequency in the m-segment areas;

[0014] Step S8, comparing the second insulation state coefficient of the cable in the j-th section area with a preset second insulation state coefficient threshold value, if the second insulation state coefficient of the cable in the j-th section area is greater than or equal to the preset second insulation state coefficient threshold value, it means that the cable insulation of the j-th section area of ​​the cable in the i-th section area is abnormal, where j belongs to m;

[0015] Step S9: Evaluate the overall life status of the cables within the monitoring area.

[0016] As a further description of the solution of the present invention, the specific working process of step S3 includes:

[0017] Every The time period is a cycle, and the cable temperature variation data of the i-th area in each cycle in the historical time period before the current moment is obtained;

[0018] Construct a coordinate system xoy, and fit the cable temperature variation curve in each cycle in the coordinate system according to the cable temperature variation data in the i-th section in each cycle;

[0019] According to the cable temperature variation curve over time in each cycle, the area enclosed by the cable temperature variation curve over time in each cycle and the x-axis is obtained;

[0020] According to the area enclosed by the cable temperature variation curve over time and the x-axis in each cycle, the area enclosed by the cable temperature variation curve over time and the x-axis is fitted. Change function ;

[0021] By formula Calculate the first insulation state coefficient of the cable in the i-th section ;

[0022] In the formula, The area enclosed by the cable temperature variation curve with time and the x-axis Variation standard function, It is the reference value of area change.

[0023] As a further description of the solution of the present invention, the specific working process of step S4 includes:

[0024] The first insulation state coefficient of the cable in the i-th section The first insulation state coefficient threshold value is preset Compare;

[0025] like , it means that the cable insulation performance in the i-th section area is normal;

[0026] like , it means that the cable insulation material in the i-th section area is aging too fast and the insulation performance is abnormal. The cable insulation status in the i-th section area is further evaluated to determine the specific area where the cable insulation status in the i-th section area is abnormal.

[0027] As a further description of the solution of the present invention, the specific working process of step S7 includes:

[0028] Get the data of cable discharge frequency variation over time in the j-th section of the historical time period before the current moment, and construct the function of cable discharge frequency variation over time in the j-th section of the historical time period ;

[0029] The second insulation state coefficient of the cable in section j is calculated according to the following formula:

[0030] ;

[0031] In the formula, is the initial moment of the historical period, For the current moment.

[0032] As a further description of the solution of the present invention, the specific working process of step S8 includes:

[0033] The second insulation state coefficient of the cable in the jth section The second insulation state coefficient threshold value is preset Compare;

[0034] like , it means that the insulation performance of the cables in the j-th section area is quite different from the average insulation performance of the cables in the entire i-th section area, and the insulation performance of the cables in the j-th section area is abnormal.

[0035] As a further description of the solution of the present invention, the specific working process of step S9 includes:

[0036] The first insulation state coefficients of the cables in the n-segment area are calculated in sequence, and compared with the preset first insulation state coefficient thresholds in sequence, and the number of areas with abnormal insulation performance is counted as follows: ;

[0037] The second insulation state coefficients of the cables in the m-segment area are calculated in sequence, and compared with the preset second insulation state coefficient thresholds in sequence, and the number of areas with abnormal insulation performance is counted as follows: ;

[0038] Construct a mathematical model for evaluating the overall life status of the cable, and the expression is:

[0039] ;

[0040] Where Y is the remaining service life of the cable as a whole. is the conversion factor.

[0041] Beneficial effects: 1. In order to realize comprehensive monitoring of long-distance transmission cables, the present invention divides the cables within the monitoring area into n sections, monitors the cable temperature data of the n sections, calculates the first insulation state coefficient of the cables in the n sections according to the cable temperature data of the n sections, and compares the first insulation state coefficient of the cables in the n sections with a preset first insulation state coefficient threshold. If an area with a first insulation state coefficient greater than or equal to the first insulation state coefficient threshold appears, it means that the insulation performance of the cables in this area is abnormal. The area with abnormal cable insulation performance is divided into m sections, the discharge frequency of the m sections is monitored, and the second insulation state coefficient of the m sections is calculated according to the discharge frequency of the m sections. The second insulation state coefficient of the m sections is compared with the preset second insulation state coefficient threshold to determine the specific area with abnormal insulation performance of the entire cable. Finally, the remaining life of the cable is estimated according to the first insulation state coefficient and the second insulation state coefficient.

[0042] 2. The present invention makes every The time period is a cycle. According to the cable temperature variation data of the i-th region in each cycle, the cable temperature variation curve in each cycle is fitted in the coordinate system. Then, the cable temperature variation curve in each cycle is obtained. The area enclosed by the cable temperature variation curve and the x-axis in each cycle is obtained and the area enclosed by the cable temperature variation curve and the x-axis is fitted. The change function is then substituted into the formula to calculate the first insulation state coefficient of the cable in the i-th section, and the first insulation state coefficient of the cable in the i-th section is compared with the preset first insulation state coefficient threshold; if the first insulation state coefficient is less than the preset first insulation state coefficient threshold, it means that the insulation performance of the cable in the i-th section is normal; if the first insulation state coefficient is greater than or equal to the preset first insulation state coefficient threshold, it means that the insulation material of the cable in the i-th section is aging too fast and the insulation performance is abnormal;

[0043] 3. The present invention obtains the data of the change of the discharge frequency of the cable in the j-th section area over time in the historical time period before the current moment, and constructs the function of the change of the discharge frequency of the cable in the j-th section area over time, and then substitutes it into the formula to calculate the second insulation state coefficient of the cable in the j-th section area, and then compares the second insulation state coefficient of the cable in the j-th section area with the preset second insulation state coefficient threshold; if the second insulation state coefficient of the cable in the j-th section area is greater than or equal to the preset second insulation state coefficient threshold, it means that the insulation performance of the cable in the j-th section area is greatly different from the average insulation performance of the cable in the entire i-th section area, and the insulation performance of the cable in the j-th section area is abnormal;

[0044] 4. The present invention obtains the number of areas with abnormal insulation performance in the n-segment cable by repeatedly calculating the first insulation state coefficient of the cable in the n-segment area, and obtains the number of areas with abnormal insulation performance in the m-segment cable by repeatedly calculating the second insulation state coefficient of the cable in the m-segment area, and then substitutes it into the mathematical model for evaluating the overall life status of the cable to estimate the overall life status of the entire cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The present invention will be further described below in conjunction with the accompanying drawings.

[0046] Figure 1 A partial flow chart of the cable operation monitoring method based on the Internet of Things provided by the present invention. DETAILED DESCRIPTION

[0047] 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.

[0048] See also Figure 1 As shown, the present invention is a cable operation monitoring method based on the Internet of Things, and the method comprises the following steps:

[0049] Step S1, divide the cables within the monitoring area into n sections, and number each section, the numbers are: 1, 2..., n;

[0050] Step S2, monitoring the cable temperature data of the n-segment area, and evaluating the insulation status according to the change of the temperature data;

[0051] Step S3, calculating the first insulation state coefficients of the cables in the n sections according to the change of the cable temperature data in the n sections;

[0052] Step S4, comparing the first insulation state coefficient of the cable in the i-th section area with a preset first insulation state coefficient threshold value, if the first insulation state coefficient of the cable in the i-th section area is greater than or equal to the first insulation state coefficient threshold value, it means that the insulation performance of the cable in the i-th section area is abnormal, and proceeding to step S5, where i belongs to n;

[0053] Step S5, dividing the i-th area into m segments, and numbering each segment in the following order: 1, 2, ..., m;

[0054] Step S6, monitoring the cable discharge frequency in the m-segment area, and further evaluating the cable insulation status in the i-th segment area according to the change in the cable discharge frequency;

[0055] Step S7, calculating the second insulation state coefficients of the cables in the m-segment areas respectively according to the change of the cable discharge frequency in the m-segment areas;

[0056] Step S8, comparing the second insulation state coefficient of the cable in the j-th section area with a preset second insulation state coefficient threshold value, if the second insulation state coefficient of the cable in the j-th section area is greater than or equal to the preset second insulation state coefficient threshold value, it means that the cable insulation of the j-th section area of ​​the cable in the i-th section area is abnormal, where j belongs to m;

[0057] Step S9: Evaluate the overall life status of the cables within the monitoring area.

[0058] Through the above technical scheme, in order to realize comprehensive monitoring of long-distance transmission cables, the present invention divides the cables within the monitoring area into n sections, monitors the cable temperature data of the n sections, calculates the first insulation state coefficient of the cables in the n sections according to the cable temperature data of the n sections, compares the first insulation state coefficient of the cables in the n sections with a preset first insulation state coefficient threshold, and if an area with a first insulation state coefficient greater than or equal to the first insulation state coefficient threshold appears, it means that the insulation performance of the cables in this area is abnormal, divides the area with abnormal cable insulation performance into m sections, monitors the discharge frequency of the m sections, calculates the second insulation state coefficient of the m sections according to the discharge frequency of the m sections, compares the second insulation state coefficient of the m sections with a preset second insulation state coefficient threshold, determines the specific area with abnormal insulation performance of the entire cable, and finally, estimates the remaining life of the cable according to the first insulation state coefficient and the second insulation state coefficient.

[0059] As a further description of the solution of the present invention, the specific working process of step S3 includes:

[0060] Every The time period is a cycle, and the cable temperature variation data of the i-th area in each cycle in the historical time period before the current moment is obtained;

[0061] Construct a coordinate system xoy, and fit the cable temperature variation curve in each cycle in the coordinate system according to the cable temperature variation data in the i-th section in each cycle;

[0062] According to the cable temperature variation curve over time in each cycle, the area enclosed by the cable temperature variation curve over time in each cycle and the x-axis is obtained;

[0063] According to the area enclosed by the cable temperature variation curve over time and the x-axis in each cycle, the area enclosed by the cable temperature variation curve over time and the x-axis is fitted. Change function ;

[0064] By formula Calculate the first insulation state coefficient of the cable in the i-th section ;

[0065] In the formula, The area enclosed by the cable temperature variation curve with time and the x-axis Variation standard function, It is the reference value of area change.

[0066] As a further description of the solution of the present invention, the specific working process of step S4 includes:

[0067] The first insulation state coefficient of the cable in the i-th section The first insulation state coefficient threshold value is preset Compare;

[0068] like , it means that the cable insulation performance in the i-th section area is normal;

[0069] like , it means that the cable insulation material in the i-th section area is aging too fast and the insulation performance is abnormal. The cable insulation status in the i-th section area is further evaluated to determine the specific area where the cable insulation status in the i-th section area is abnormal.

[0070] Through the above calculation scheme, this embodiment makes every The time period is a cycle. According to the cable temperature variation data of the i-th region in each cycle, the cable temperature variation curve in each cycle is fitted in the coordinate system. Then, the cable temperature variation curve in each cycle is obtained. The area enclosed by the cable temperature variation curve and the x-axis in each cycle is obtained and the area enclosed by the cable temperature variation curve and the x-axis is fitted. The change function is then substituted into the formula to calculate the first insulation state coefficient of the cable in the i-th section, and the first insulation state coefficient of the cable in the i-th section is compared with the preset first insulation state coefficient threshold; if the first insulation state coefficient is less than the preset first insulation state coefficient threshold, it means that the insulation performance of the cable in the i-th section is normal; if the first insulation state coefficient is greater than or equal to the preset first insulation state coefficient threshold, it means that the insulation material of the cable in the i-th section is aging too fast and the insulation performance is abnormal.

[0071] As a further description of the solution of the present invention, the specific working process of step S7 includes:

[0072] Get the data of cable discharge frequency variation over time in the j-th section of the historical time period before the current moment, and construct the function of cable discharge frequency variation over time in the j-th section of the historical time period ;

[0073] The second insulation state coefficient of the cable in section j is calculated according to the following formula:

[0074] ;

[0075] In the formula, is the initial moment of the historical period, For the current moment.

[0076] As a further description of the solution of the present invention, the specific working process of step S8 includes:

[0077] The second insulation state coefficient of the cable in the jth section The second insulation state coefficient threshold value is preset Compare;

[0078] like , it means that the insulation performance of the cables in the j-th section area is quite different from the average insulation performance of the cables in the entire i-th section area, and the insulation performance of the cables in the j-th section area is abnormal.

[0079] Through the above calculation scheme, this embodiment obtains the time-varying data of the cable discharge frequency in the j-th section area in the historical time period before the current moment, and constructs the time-varying function of the cable discharge frequency in the j-th section area, and then substitutes it into the formula to calculate the second insulation state coefficient of the cable in the j-th section area, where, It indicates the change of average discharge frequency of cable in segment m over time. It represents the change of the discharge frequency of the cable in the j-th section area over time, and then compares the second insulation state coefficient of the cable in the j-th section area with the preset second insulation state coefficient threshold; if the second insulation state coefficient of the cable in the j-th section area is greater than or equal to the preset second insulation state coefficient threshold, it means that the insulation performance of the cable in the j-th section area is greatly different from the average insulation performance of the cable in the entire i-th section area, and the insulation performance of the cable in the j-th section area is abnormal.

[0080] As a further description of the solution of the present invention, the specific working process of step S9 includes:

[0081] The first insulation state coefficients of the cables in the n-segment area are calculated in sequence, and compared with the preset first insulation state coefficient thresholds in sequence, and the number of areas with abnormal insulation performance is counted as follows: ;

[0082] The second insulation state coefficients of the cables in the m-segment area are calculated in sequence, and compared with the preset second insulation state coefficient thresholds in sequence, and the number of areas with abnormal insulation performance is counted as follows: ;

[0083] Construct a mathematical model for evaluating the overall life status of the cable, and the expression is:

[0084] ;

[0085] Where Y is the remaining service life of the cable as a whole and is the conversion coefficient.

[0086] Through the above technical scheme, the present invention obtains the number of areas with abnormal insulation performance in the n-segment cable by repeatedly calculating the first insulation state coefficient of the cable in the n-segment area, obtains the number of areas with abnormal insulation performance in the m-segment cable by repeatedly calculating the second insulation state coefficient of the cable in the m-segment area, and then substitutes it into the mathematical model for evaluating the overall life status of the cable to estimate the overall life status of the entire cable.

[0087] It should be noted that the thresholds and coefficients involved in this application are all empirical data.

[0088] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A cable operation monitoring method based on the Internet of Things, characterized in that: The method comprises the following steps: Step S1, divide the cables within the monitoring area into n sections, and number each section, the numbers are: 1, 2..., n; Step S2, monitoring the cable temperature data of the n-segment area, and evaluating the insulation status according to the change of the temperature data; Step S3, calculating the first insulation state coefficients of the cables in the n sections respectively according to the change of the cable temperature data in the n sections; Step S4, comparing the first insulation state coefficient of the cable in the i-th section area with a preset first insulation state coefficient threshold value, if the first insulation state coefficient of the cable in the i-th section area is greater than or equal to the first insulation state coefficient threshold value, it means that the insulation performance of the cable in the i-th section area is abnormal, and proceeding to step S5, where i belongs to n; Step S5, dividing the i-th area into m segments, and numbering each segment in the following order: 1, 2, ..., m; Step S6, monitoring the cable discharge frequency in the m-segment area, and further evaluating the cable insulation status in the i-th segment area according to the change in the cable discharge frequency; Step S7, calculating the second insulation state coefficients of the cables in the m-segment areas respectively according to the change of the cable discharge frequency in the m-segment areas; Step S8, comparing the second insulation state coefficient of the cable in the j-th section area with a preset second insulation state coefficient threshold value, if the second insulation state coefficient of the cable in the j-th section area is greater than or equal to the preset second insulation state coefficient threshold value, it means that the cable insulation of the j-th section area of ​​the cable in the i-th section area is abnormal, where j belongs to m; Step S9, evaluating the overall life status of the cables within the monitoring area; The specific working process of step S3 includes: Let every Δt time period be a cycle, and obtain the cable temperature variation data of the i-th area in each cycle in the historical time period before the current moment; Construct a coordinate system xoy, and fit the cable temperature variation curve in each cycle in the coordinate system according to the cable temperature variation data in the i-th section in each cycle; According to the cable temperature variation curve over time in each cycle, the area enclosed by the cable temperature variation curve over time in each cycle and the x-axis is obtained; According to the area enclosed by the cable temperature variation curve with time and the x-axis in each cycle, the area enclosed by the cable temperature variation curve with time and the x-axis is fitted with the function S of the area enclosed by the cable temperature variation curve with time and the x-axis with Δt i Δt; By formula Calculate the first insulation state coefficient ρ of the cable in the i-th section i ; In the formula, S i0 Δt is the standard function of the area enclosed by the cable temperature variation curve with time and the x-axis with Δt, S th is the reference value of area change; The specific working process of step S7 includes: Obtain the data of cable discharge frequency variation over time in the j-th section of the historical time period before the current moment, and construct the function X of cable discharge frequency variation over time in the j-th section of the historical time period before the current moment. j t; The second insulation state coefficient of the cable in section j is calculated according to the following formula: In the formula, t1 is the initial time of the historical time period, and t2 is the current time; The specific working process of step S9 includes: Calculate the first insulation state coefficient of the cable in n sections in turn, and compare it with the preset first insulation state coefficient threshold in turn, and count the number of areas with abnormal insulation performance as n δ ; The second insulation state coefficients of the cables in the m-segment area are calculated in sequence, and compared with the preset second insulation state coefficient thresholds in sequence. The number of areas with abnormal insulation performance is counted as m. δ ; Construct a mathematical model for evaluating the overall life status of the cable, and the expression is: Where Y is the remaining service life of the cable and μ is the conversion coefficient.

2. The cable operation monitoring method based on the Internet of Things according to claim 1 is characterized in that: The specific working process of step S4 includes: The first insulation state coefficient ρ of the cable in the i-th section i and the preset first insulation state coefficient threshold ρ i0 Compare; If i <ρ i0 , it means that the cable insulation performance in the i-th section area is normal; If i ≥ρ i0 , it means that the cable insulation material in the i-th section area is aging too fast and the insulation performance is abnormal. The cable insulation status in the i-th section area is further evaluated to determine the specific area where the cable insulation status in the i-th section area is abnormal.

3. A cable operation monitoring method based on the Internet of Things according to claim 2, characterized in that: The specific working process of step S8 includes: The second insulation state coefficient σ of the cable in the jth section j and the preset second insulation state coefficient threshold σ j0 Compare; If σ j ≥σ j0 , it means that the insulation performance of the cables in the j-th section area is quite different from the average insulation performance of the cables in the entire i-th section area, and the insulation performance of the cables in the j-th section area is abnormal.

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