Cable temperature real-time monitoring method and system considering unsteady state, terminal and medium

Abstract

The invention discloses a cable temperature real-time monitoring method and system considering an unsteady state, a terminal and a medium, and relates to the field of cable temperature monitoring, and the key points of the technical scheme are as follows: on the basis of the change trend of the surface temperature of a cable, reverse coupling decomposition is performed on the influence of the environment temperature and the cable current change on the surface temperature; the change quantity and the starting time of the environment temperature and the cable current can be determined, and the collected data does not need to cover the starting time of the environment temperature and / or the cable current change; and the surface steady-state temperature of the target cable is solved by coupling the pre-estimated linear parameter sequence and the pre-estimated discrete parameter sequence, and the pre-estimated temperature of the cable core is calculated by using the cable steady-state conductor temperature calculation model, so that advanced monitoring of the final temperature of the cable core under the non-steady-state condition is realized, and the real-time monitoring of the final temperature of the cable core under the non-steady-state condition is realized. And the reliability of cable temperature real-time monitoring is improved.

Description

Technical Field

[0001] The present invention relates to the field of cable temperature monitoring, and more specifically, to a real-time cable temperature monitoring method, system, terminal and medium taking non-steady state into consideration. Background Art

[0002] The cable core temperature is an important parameter for the safe operation of power cables. For example, the maximum long-term temperature of the cable core of cross-linked polyethylene insulated power cables is 90°C; the short-term overload operating temperature shall not exceed 130°C, and the cumulative operating time throughout the year shall not exceed 100 hours; the core short-circuit temperature shall not exceed 250°C, and the duration shall not exceed 2 seconds.

[0003] At present, the calculation methods of cable core temperature can be divided into two categories: steady-state calculation and non-steady-state calculation. (1) The steady-state calculation method is mainly based on the corresponding formula in the IEC-60287 standard and the steady-state thermal circuit of the cable. This method assumes that the external environmental conditions are constant. When a single-core cable is continuously operating at the rated current carrying capacity, the core, insulation, metal sheath, outer sheath and other parts will generate losses and emit heat to form a steady-state temperature field. The principle of this method is to calculate the cable loss and thermal resistance based on the material structure parameters and laying conditions of the cable. The temperature of the conductor is calculated layer by layer by the temperature rise of each layer of the cable. (2) The non-steady-state calculation method takes into account the temperature change of the cable under non-constant load or environmental conditions. These methods usually require the establishment of a transient thermal circuit model of the cable body and the surrounding medium, and the introduction of the concept of thermal time constant to study the calculation method of the transient conductor temperature of the cable under emergency load conditions. The non-steady-state calculation method can more accurately simulate the temperature change of the cable in actual operation, especially when the load changes are large or the environmental conditions are unstable.

[0004] However, in the actual operation of the cable, the time under steady-state conditions accounts for a relatively small proportion, so the cable temperature monitoring technology considering non-steady-state conditions has become the main research direction at present. Since the thermal time constant in the transient thermal circuit model determines the rate of change of the cable core temperature, the existing non-steady-state calculation method needs to collect the starting time of the load or environmental conditions change, which requires the monitoring equipment that collects data to run in real time, such as optical fiber sensors, thermal effect temperature sensors, etc. If the monitoring equipment randomly collects data for non-steady-state calculation, it is easy to collect the cable surface temperature after the load and / or ambient temperature has changed for a period of time. At this time, the collected cable surface temperature has already undergone a thermal effect, so it is easy to cause a large deviation in the calculated cable core temperature. Therefore, how to study and design a real-time cable temperature monitoring method, system, terminal and medium that can overcome the above-mentioned defects and consider non-steady states is a problem that we urgently need to solve. Summary of the invention

[0005] In order to address the deficiencies in the prior art, the purpose of the present invention is to provide a real-time cable temperature monitoring method, system, terminal and medium taking non-steady state into consideration, which can determine the amount and starting time of changes in ambient temperature and cable current, without requiring the collected data to cover the starting time of changes in ambient temperature and / or cable current, and realizes early monitoring of the final temperature of the cable core under non-steady state conditions, thereby improving the reliability of real-time cable temperature monitoring.

[0006] The above technical objectives of the present invention are achieved through the following technical solutions: In a first aspect, a real-time cable temperature monitoring method considering non-steady state is provided, comprising the following steps: Collect the real-time current value of the target cable and the surface temperature data and ambient temperature data within a preset time period; Correcting the surface temperature data according to the ambient temperature data to obtain surface temperature correction data; Taking the surface temperature correction data as the coupling result, a set of optimal linear parameter sequences and discrete parameter sequences are screened out from the pre-constructed linear parameter matrix and discrete parameter matrix; According to the linear parameter sequence, an estimated linear parameter sequence is intercepted from the linear parameter matrix, wherein the starting estimated linear parameter in the estimated linear parameter sequence is adjacent to the terminating linear parameter in the linear parameter sequence, and the terminating estimated linear parameter in the estimated linear parameter sequence represents that the influence of the ambient temperature change on the surface temperature is in a steady state; According to the discrete parameter sequence, an estimated discrete parameter sequence is intercepted from the discrete parameter matrix, the estimated discrete parameter at the beginning of the estimated discrete parameter sequence is adjacent to the discrete parameter at the end of the discrete parameter sequence, and the estimated discrete parameter at the end of the estimated discrete parameter sequence represents that the influence of the cable current change on the surface temperature is in a steady state; The estimated linear parameter sequence and the estimated discrete parameter sequence are coupled to solve the surface steady-state temperature of the target cable; The surface steady-state temperature, real-time ambient temperature and real-time current value are input into the cable steady-state conductor temperature calculation model to calculate the estimated temperature of the cable core.

[0007] Furthermore, the calculation formula of the surface temperature correction data is specifically: ; in, Indicates surface temperature correction data Temperature value at the moment; Indicates surface temperature data Temperature value at the moment; Indicates the ambient temperature data Temperature value at the moment; Indicates the ambient temperature data Temperature value at the moment; Or, the calculation formula of the surface temperature correction data is specifically: ; in, Indicates the temperature value at the start time in the ambient temperature data.

[0008] Furthermore, the linear parameters in the linear parameter matrix represent a first temperature change ratio of the cable surface temperature change caused by the corresponding change temperature within the corresponding continuous change time; The first temperature change ratio is: the ratio of the final temperature of the cable surface to the initial temperature of the cable surface after the ambient temperature changes at a corresponding change temperature and a corresponding continuous change time has passed; And / or, the discrete parameters in the discrete parameter matrix represent a second temperature transformation ratio of the cable surface temperature change caused by the corresponding changing current within the corresponding continuous change time; The second temperature change ratio is: the ratio of the final temperature of the cable surface to the initial temperature of the cable surface after the cable current changes with a corresponding change current and after a corresponding continuous change time.

[0009] Furthermore, the expression of the linear parameter matrix is: ; in, Indicates the change in ambient temperature In the continuous change time The first temperature ratio causing the cable surface temperature change; Indicates the sampling time interval; Indicates the number of time sampling; Indicates the sampling temperature interval; Indicates the number of temperature sampling times; Indicates the ambient temperature as a function of the temperature change Changes, and after a period of continuous change Final temperature of the rear cable surface; Indicates the starting temperature of the cable surface.

[0010] Furthermore, the expression of the discrete parameter matrix is ​​specifically: ; in, Indicates the changing current of the cable current In the continuous change time The second temperature ratio causing the cable surface temperature change; Indicates the sampling time interval; Indicates the number of time sampling; Indicates the sampling current interval; Indicates the number of current sampling times; Indicates cable current as variable current Changes, and after a period of continuous change Final temperature of the rear cable surface; Indicates the starting temperature of the cable surface.

[0011] Furthermore, the surface temperature correction data is used as the coupling result, and the expression for selecting a set of optimal linear parameter sequences and discrete parameter sequences from the pre-constructed linear parameter matrix and discrete parameter matrix is ​​specifically: ; in, Respectively represent the starting time 0 and time in the surface temperature correction data , the end time Temperature value; The initial ambient temperature at the beginning of the ambient temperature change is an unknown quantity, which is eliminated by the ratio of different temperature values ​​in the surface temperature correction data; Respectively represent the change of ambient temperature In the continuous change time The first temperature ratio causing the cable surface temperature change; Represents the change of cable current In the continuous change time The second temperature ratio causing the cable surface temperature change; Respectively represent the starting time 0 and time in the surface temperature correction data , the end time Coupling parameters for coupling the temperature value; represents the optimal linear parameter sequence; represents the optimal discrete parameter sequence.

[0012] Furthermore, the surface steady-state temperature solution process of the target cable is specifically as follows: Fitting analysis is performed on each coupling parameter in the process of selecting the optimal linear parameter sequence and discrete parameter sequence, and the coupling parameters are predicted in the prediction stage when the influence of ambient temperature change and cable current change on surface temperature tends to be steady state; The predicted coupled parameters, estimated linear parameter sequence and estimated discrete parameter sequence are coupled to analyze the predicted surface temperature value in the prediction stage, and the surface steady-state temperature is screened out from the predicted surface temperature value.

[0013] In a second aspect, a real-time cable temperature monitoring system considering non-steady state is provided, the system is used to implement the real-time cable temperature monitoring method considering non-steady state as described in any one of the first aspects, including: A data acquisition module is used to collect the real-time current value of the target cable and the surface temperature data and ambient temperature data within a preset time period; A data correction module is used to correct the surface temperature data according to the ambient temperature data to obtain surface temperature correction data; A parameter screening module is used to screen out a set of optimal linear parameter sequences and discrete parameter sequences from pre-built linear parameter matrices and discrete parameter matrices using surface temperature correction data as coupling results; A linear interception module is used to intercept an estimated linear parameter sequence from a linear parameter matrix according to a linear parameter sequence, wherein the starting estimated linear parameter in the estimated linear parameter sequence is adjacent to the terminating linear parameter in the linear parameter sequence, and the terminating estimated linear parameter in the estimated linear parameter sequence represents that the influence of the ambient temperature change on the surface temperature is in a steady state; A discrete interception module intercepts an estimated discrete parameter sequence from a discrete parameter matrix according to a discrete parameter sequence, wherein the estimated discrete parameter at the beginning of the estimated discrete parameter sequence is adjacent to the discrete parameter at the end of the estimated discrete parameter sequence, and the estimated discrete parameter at the end of the estimated discrete parameter sequence represents that the influence of the cable current change on the surface temperature is in a steady state; The temperature coupling module is used to couple the estimated linear parameter sequence and the estimated discrete parameter sequence to solve the surface steady-state temperature of the target cable; The temperature estimation module is used to input the surface steady-state temperature, real-time ambient temperature and real-time current value into the cable steady-state conductor temperature calculation model to calculate the estimated temperature of the cable core.

[0014] In a third aspect, a computer terminal is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, a real-time cable temperature monitoring method taking non-steady state into consideration as described in any one of the first aspects is implemented.

[0015] In a fourth aspect, a computer-readable medium is provided, on which a computer program is stored, and the computer program is executed by a processor to implement the real-time cable temperature monitoring method considering non-steady state as described in any one of the first aspects.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The real-time cable temperature monitoring method considering non-steady state provided by the present invention is based on the change trend of the cable surface temperature. By reverse coupling and decomposing the influence of the ambient temperature and cable current changes on the surface temperature, the amount and starting time of the ambient temperature and cable current changes can be determined, without requiring the collected data to cover the starting time of the ambient temperature and / or cable current changes; and by coupling the estimated linear parameter sequence and the estimated discrete parameter sequence, the surface steady-state temperature of the target cable is solved, and the cable steady-state conductor temperature calculation model is used to calculate the estimated temperature of the cable core, thereby realizing the early monitoring of the final temperature of the cable core under non-steady-state conditions and improving the reliability of real-time monitoring of the cable temperature; 2. The present invention corrects the surface temperature data according to the ambient temperature data, which can eliminate the influence of local changes in the ambient temperature data on the coupling analysis, and effectively improves the accuracy of determining the amount and starting time of the ambient temperature and cable current changes; 3. When solving the surface steady-state temperature of the target cable, the present invention not only considers the continuous influence of the single ambient temperature and cable current changes on the surface temperature, but also considers the subsequent changes of the coupling parameters, so that the calculation result of the surface steady-state temperature is more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings: Figure 1 is a flow chart of Embodiment 1 of the present invention; Figure 2 It is a system block diagram in Example 2 of the present invention. DETAILED DESCRIPTION

[0018] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0019] Embodiment 1: Considering the real-time monitoring method of cable temperature in a non-steady state, such as Figure 1 As shown, the following steps are included: S1: Collect the real-time current value of the target cable and the surface temperature data and ambient temperature data within a preset time period; S2: Correcting the surface temperature data according to the ambient temperature data to obtain surface temperature correction data; S3: Taking the surface temperature correction data as the coupling result, a set of optimal linear parameter sequences and discrete parameter sequences are screened out from the pre-constructed linear parameter matrix and discrete parameter matrix; S4: extracting an estimated linear parameter sequence from the linear parameter matrix according to the linear parameter sequence, wherein the starting estimated linear parameter in the estimated linear parameter sequence is adjacent to the terminating linear parameter in the linear parameter sequence, and the terminating estimated linear parameter in the estimated linear parameter sequence represents that the influence of the ambient temperature change on the surface temperature is in a steady state; S5: extracting an estimated discrete parameter sequence from the discrete parameter matrix according to the discrete parameter sequence, wherein the estimated discrete parameter at the beginning of the estimated discrete parameter sequence is adjacent to the discrete parameter at the end of the estimated discrete parameter sequence, and the estimated discrete parameter at the end of the estimated discrete parameter sequence represents that the influence of the cable current change on the surface temperature is in a steady state; S6: coupling the estimated linear parameter sequence and the estimated discrete parameter sequence to solve the surface steady-state temperature of the target cable; S7: The surface steady-state temperature, the real-time ambient temperature and the real-time current value are input into the cable steady-state conductor temperature calculation model to calculate the estimated temperature of the cable core.

[0020] In step S1, the preset time period may be 30 minutes, 60 minutes, or 90 minutes, and may be flexibly set according to the load and the frequency of ambient temperature changes.

[0021] For example, the collection time range of surface temperature data and ambient temperature data on October 10, 2022 is [16:00, 17:00], and the real-time current value should be collected at 17:00 on October 10, 2022.

[0022] In step S2, considering that the change of ambient temperature has a linear effect on the surface temperature, in order to eliminate the interference of the local change of ambient temperature on the subsequent coupling, the surface temperature data needs to be corrected.

[0023] As an optional implementation, the calculation formula of the surface temperature correction data is specifically: ; in, Indicates surface temperature correction data Temperature value at the moment; Indicates surface temperature data Temperature value at the moment; Indicates the ambient temperature data Temperature value at the moment; Indicates the ambient temperature data The temperature value at the moment.

[0024] As another optional implementation, the calculation formula of the surface temperature correction data is specifically: ; in, Indicates the temperature value at the start time in the ambient temperature data.

[0025] In step S3, the linear parameters in the linear parameter matrix represent the first temperature ratio of the cable surface temperature caused by the corresponding change temperature within the corresponding continuous change time; wherein the first temperature ratio is: the ratio of the final temperature of the cable surface to the starting temperature of the cable surface after the ambient temperature changes with the corresponding change temperature and after the corresponding continuous change time.

[0026] The discrete parameters in the discrete parameter matrix represent the second temperature ratio of the cable surface temperature change caused by the corresponding changing current within the corresponding continuous changing time; wherein the second temperature ratio is: the ratio of the final temperature of the cable surface to the starting temperature of the cable surface after the cable current changes with the corresponding changing current and after the corresponding continuous changing time.

[0027] It should be noted that the first temperature ratio can be obtained by experimental measurement with ambient temperature as a single variable, and other conditions in the experimental process can be taken as the average value of the actual working conditions within a certain period of time. Similarly, the second temperature ratio can be obtained by experimental measurement with cable current as a single variable, and other conditions in the experimental process can be taken as the average value of the actual working conditions within a certain period of time. In addition, the first temperature ratio and the second temperature ratio can also be obtained by simulation, which is not limited here.

[0028] In this embodiment, the linear parameters and the discrete parameters can be sampled at equal intervals, and the sampling numbers of the linear parameter matrix and the discrete parameter matrix can be kept consistent.

[0029] For example, the linear parameter matrix is ​​expressed as: ; in, Indicates the change in ambient temperature In the continuous change time The first temperature ratio causing the cable surface temperature change; Indicates the sampling time interval; Indicates the number of time sampling; Indicates the sampling temperature interval; Indicates the number of temperature sampling times; Indicates the ambient temperature as a function of the temperature change Changes, and after a period of continuous change Final temperature of the rear cable surface; Indicates the starting temperature of the cable surface.

[0030] It should be noted that when the influence of the change in ambient temperature on the cable surface temperature is in a steady state, the first temperature change ratio takes a value of 1.

[0031] For example, the expression of the discrete parameter matrix is ​​as follows: ; in, Indicates the changing current of the cable current In the continuous change time The second temperature ratio causing the cable surface temperature change; Indicates the sampling time interval; Indicates the number of time sampling; Indicates the sampling current interval; Indicates the number of current sampling times; Indicates cable current as variable current Changes, and after a period of continuous change Final temperature of the rear cable surface; Indicates the starting temperature of the cable surface.

[0032] It should be noted that when the effect of the change in cable current on the cable surface temperature is in a steady state, the second temperature change ratio takes a value of 1.

[0033] In this embodiment, the surface temperature correction data is used as the coupling result, and a set of optimal linear parameter sequences and discrete parameter sequences corresponding to the minimum sum of coupling parameters are screened out from the pre-constructed linear parameter matrix and discrete parameter matrix. The specific expression is: ; in, Respectively represent the starting time 0 and time in the surface temperature correction data , the end time Temperature value; The initial ambient temperature at the beginning of the ambient temperature change is an unknown quantity, which is eliminated by the ratio of different temperature values ​​in the surface temperature correction data; Respectively represent the change of ambient temperature In the continuous change time The first temperature ratio causing the cable surface temperature change; Represents the change of cable current In the continuous change time The second temperature ratio causing the cable surface temperature change; Respectively represent the starting time 0 and time in the surface temperature correction data , the end time Coupling parameters for coupling the temperature value; represents the optimal linear parameter sequence; represents the optimal discrete parameter sequence.

[0034] In step S4, if a row of data in the linear parameter matrix is ,in The value is not 1. The value is 1; when the selected linear parameter sequence is When , the estimated linear parameter sequence is .

[0035] In step S5, if a row of data in the discrete parameter matrix is ,in The value is not 1. The value is 1; when the selected discrete parameter sequence is When , the estimated discrete parameter sequence is .

[0036] From the above linear parameter sequence and discrete parameter sequence, it can be seen that in this working condition, the current and ambient temperature change simultaneously. From the estimated linear parameter sequence and estimated discrete parameter sequence, it can be seen that the impact of current change on surface temperature is first in a steady state.

[0037] In step S6, the surface steady-state temperature solution process of the target cable is specifically as follows: fitting and analyzing the various coupling parameters in the optimal linear parameter sequence and discrete parameter sequence screening process, predicting the predicted coupling parameters in the prediction stage when the influence of ambient temperature changes and cable current changes on the surface temperature tends to a steady state; combining the predicted coupling parameters, the estimated linear parameter sequence and the estimated discrete parameter sequence to couple and analyze the predicted value of the surface temperature in the prediction stage, and screening out the surface steady-state temperature from the surface temperature prediction value.

[0038] Taking the estimated linear parameter sequence and the estimated discrete parameter sequence intercepted in steps S4 and S5 as an example, the estimated linear parameter sequence still needs three data to reach a steady state, and the estimated discrete parameter sequence still needs two data to reach a steady state. Three data are required for all to reach a steady state. Therefore, it is also necessary to fit and predict the coupling parameters corresponding to the previous four data to obtain the subsequent three predicted coupling parameters.

[0039] In step S7, the cable steady-state conductor temperature calculation model described in the present invention takes into account the surface temperature, ambient temperature and current. The cable steady-state conductor temperature calculation model can also be replaced by a model that does not require ambient temperature, which is not limited here.

[0040] Embodiment 2: A real-time cable temperature monitoring system considering non-steady state, the system is used to implement the real-time cable temperature monitoring method considering non-steady state as described in Embodiment 1, such as Figure 2 As shown, it includes a data acquisition module, a data correction module, a parameter screening module, a linear interception module, a discrete interception module, a temperature coupling module and a temperature estimation module.

[0041] Among them, the data acquisition module is used to collect the real-time current value of the target cable and the surface temperature data and ambient temperature data within a preset time period; the data correction module is used to correct the surface temperature data according to the ambient temperature data to obtain the surface temperature correction data; the parameter screening module is used to use the surface temperature correction data as the coupling result to screen out a set of optimal linear parameter sequences and discrete parameter sequences from the pre-constructed linear parameter matrix and discrete parameter matrix; the linear interception module is used to intercept the estimated linear parameter sequence from the linear parameter matrix according to the linear parameter sequence, the estimated linear parameter starting from the estimated linear parameter sequence is adjacent to the linear parameter ending in the linear parameter sequence, and the estimated linear parameter ending in the estimated linear parameter sequence is adjacent to the linear parameter ending in the linear parameter sequence. The linear parameter characterization effect of ambient temperature change on surface temperature is in steady state; the discrete interception module, according to the discrete parameter sequence, intercepts the estimated discrete parameter sequence from the discrete parameter matrix, the estimated discrete parameter starting in the estimated discrete parameter sequence is adjacent to the discrete parameter terminating in the discrete parameter sequence, and the estimated discrete parameter terminating in the estimated discrete parameter sequence characterizes that the effect of cable current change on surface temperature is in steady state; the temperature coupling module, used to couple the estimated linear parameter sequence and the estimated discrete parameter sequence, and solve the surface steady-state temperature of the target cable; the temperature estimation module, used to input the surface steady-state temperature, real-time ambient temperature and real-time current value into the cable steady-state conductor temperature calculation model, and calculate the estimated temperature of the cable core.

[0042] The present invention also records a computer terminal, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the real-time cable temperature monitoring method taking non-steady state into consideration as described in Example 1 is implemented.

[0043] The present invention also describes a computer-readable medium on which a computer program is stored. The computer program is executed by a processor to implement the real-time cable temperature monitoring method taking non-steady state into consideration as described in Example 1.

[0044] Working principle: The present invention is based on the changing trend of the cable surface temperature. By reversely coupling and decomposing the effects of ambient temperature and cable current changes on the surface temperature, the amount and starting time of the changes in ambient temperature and cable current can be determined, without requiring the collected data to cover the starting time of the changes in ambient temperature and / or cable current; and by coupling the estimated linear parameter sequence and the estimated discrete parameter sequence, the surface steady-state temperature of the target cable is solved, and the cable steady-state conductor temperature calculation model is used to calculate the estimated temperature of the cable core, thereby realizing the early monitoring of the final temperature of the cable core under non-steady-state conditions and improving the reliability of real-time monitoring of the cable temperature.

[0045] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0046] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0047] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0048] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0049] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A real-time cable temperature monitoring method considering non-steady state is characterized by: The following steps are involved: Collect the real-time current value of the target cable and the surface temperature data and ambient temperature data within a preset time period; Correcting the surface temperature data according to the ambient temperature data to obtain surface temperature correction data; Taking the surface temperature correction data as the coupling result, a set of optimal linear parameter sequences and discrete parameter sequences are screened out from the pre-constructed linear parameter matrix and discrete parameter matrix; According to the linear parameter sequence, an estimated linear parameter sequence is intercepted from the linear parameter matrix, wherein the starting estimated linear parameter in the estimated linear parameter sequence is adjacent to the terminating linear parameter in the linear parameter sequence, and the terminating estimated linear parameter in the estimated linear parameter sequence represents that the influence of the ambient temperature change on the surface temperature is in a steady state; According to the discrete parameter sequence, an estimated discrete parameter sequence is intercepted from the discrete parameter matrix, the estimated discrete parameter at the beginning of the estimated discrete parameter sequence is adjacent to the discrete parameter at the end of the discrete parameter sequence, and the estimated discrete parameter at the end of the estimated discrete parameter sequence represents that the influence of the cable current change on the surface temperature is in a steady state; The estimated linear parameter sequence and the estimated discrete parameter sequence are coupled to solve the surface steady-state temperature of the target cable; The surface steady-state temperature, real-time ambient temperature and real-time current value are input into the cable steady-state conductor temperature calculation model to calculate the estimated temperature of the cable core.

2. The real-time cable temperature monitoring method considering non-steady state according to claim 1 is characterized in that: The calculation formula of the surface temperature correction data is specifically: ； in, Indicates surface temperature correction data Temperature value at the moment; Indicates surface temperature data Temperature value at the moment; Indicates the ambient temperature data Temperature value at the moment; Indicates the ambient temperature data Temperature value at the moment; Or, the calculation formula of the surface temperature correction data is specifically: ； in, Indicates the temperature value at the start time in the ambient temperature data.

3. The real-time cable temperature monitoring method considering non-steady state according to claim 1 is characterized in that: The linear parameters in the linear parameter matrix represent the first temperature change ratio of the cable surface temperature caused by the corresponding change temperature within the corresponding continuous change time; The first temperature change ratio is: the ratio of the final temperature of the cable surface to the initial temperature of the cable surface after the ambient temperature changes at a corresponding change temperature and after a corresponding continuous change time; And / or, the discrete parameters in the discrete parameter matrix represent a second temperature transformation ratio of the cable surface temperature change caused by the corresponding changing current within the corresponding continuous change time; The second temperature change ratio is: the ratio of the final temperature of the cable surface to the initial temperature of the cable surface after the cable current changes with a corresponding change current and a corresponding continuous change time has passed.

4. The real-time cable temperature monitoring method considering non-steady state according to claim 3 is characterized in that: The expression of the linear parameter matrix is: ； in, Indicates the change in ambient temperature In the continuous change time The first temperature ratio causing the cable surface temperature change; Indicates the sampling time interval; Indicates the number of time sampling; Indicates the sampling temperature interval; Indicates the number of temperature sampling times; Indicates the ambient temperature as a function of the temperature change Changes, and after a period of continuous change Final temperature of the rear cable surface; Indicates the starting temperature of the cable surface.

5. The real-time cable temperature monitoring method considering non-steady state according to claim 3 is characterized in that: The expression of the discrete parameter matrix is ​​specifically: ； in, Indicates the changing current of the cable current In the continuous change time The second temperature ratio causing the cable surface temperature change; Indicates the sampling time interval; Indicates the number of time sampling; Indicates the sampling current interval; Indicates the number of current sampling times; Indicates cable current as variable current Changes, and after a period of continuous change Final temperature of the rear cable surface; Indicates the starting temperature of the cable surface.

6. The real-time cable temperature monitoring method considering non-steady state according to claim 1 is characterized in that: The specific expression of selecting a set of optimal linear parameter sequences and discrete parameter sequences from the pre-constructed linear parameter matrix and discrete parameter matrix using the surface temperature correction data as the coupling result is: ； in, Respectively represent the starting time 0 and time in the surface temperature correction data , the end time Temperature value; The initial ambient temperature at the beginning of the ambient temperature change is an unknown quantity, which is eliminated by the ratio of different temperature values ​​in the surface temperature correction data; Respectively represent the change of ambient temperature In the continuous change time The first temperature ratio causing the cable surface temperature change; Represents the change of cable current In the continuous change time The second temperature ratio causing the cable surface temperature change; Respectively represent the starting time 0 and time in the surface temperature correction data , the end time Coupling parameters for coupling the temperature value; represents the optimal linear parameter sequence; represents the optimal discrete parameter sequence.

7. The real-time cable temperature monitoring method considering non-steady state according to claim 1 is characterized in that: The specific process of solving the surface steady-state temperature of the target cable is as follows: Fitting analysis is performed on each coupling parameter in the process of selecting the optimal linear parameter sequence and discrete parameter sequence, and the coupling parameters are predicted in the prediction stage when the influence of ambient temperature change and cable current change on surface temperature tends to be steady state; The predicted coupled parameters, estimated linear parameter sequence and estimated discrete parameter sequence are coupled to analyze the predicted surface temperature value in the prediction stage, and the surface steady-state temperature is screened out from the predicted surface temperature value.

8. Considering the non-steady-state cable temperature real-time monitoring system, its characteristics are: The system is used to implement the real-time cable temperature monitoring method considering non-steady state as described in any one of claims 1 to 7, comprising: A data acquisition module is used to collect the real-time current value of the target cable and the surface temperature data and ambient temperature data within a preset time period; A data correction module is used to correct the surface temperature data according to the ambient temperature data to obtain surface temperature correction data; A parameter screening module is used to screen out a set of optimal linear parameter sequences and discrete parameter sequences from pre-built linear parameter matrices and discrete parameter matrices using surface temperature correction data as coupling results; A linear interception module is used to intercept an estimated linear parameter sequence from a linear parameter matrix according to a linear parameter sequence, wherein the starting estimated linear parameter in the estimated linear parameter sequence is adjacent to the terminating linear parameter in the linear parameter sequence, and the terminating estimated linear parameter in the estimated linear parameter sequence represents that the influence of the ambient temperature change on the surface temperature is in a steady state; A discrete interception module intercepts an estimated discrete parameter sequence from a discrete parameter matrix according to a discrete parameter sequence, wherein the estimated discrete parameter at the beginning of the estimated discrete parameter sequence is adjacent to the discrete parameter at the end of the estimated discrete parameter sequence, and the estimated discrete parameter at the end of the estimated discrete parameter sequence represents that the influence of the cable current change on the surface temperature is in a steady state; The temperature coupling module is used to couple the estimated linear parameter sequence and the estimated discrete parameter sequence to solve the surface steady-state temperature of the target cable; The temperature estimation module is used to input the surface steady-state temperature, real-time ambient temperature and real-time current value into the cable steady-state conductor temperature calculation model to calculate the estimated temperature of the cable core.

9. A computer terminal comprising a memory, a processor and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the real-time cable temperature monitoring method taking non-steady state into consideration as described in any one of claims 1 to 7 is implemented.

10. A computer readable medium having a computer program stored thereon, characterized in that: The computer program is executed by a processor to implement the real-time cable temperature monitoring method taking non-steady state into consideration as described in any one of claims 1 to 7.

Images