Power cable temperature field evaluation method, system, equipment, medium and procedure

Abstract

The present invention relates to the field of temperature assessment technology, and provides a method, system, device, medium and program for assessing the temperature field of a power cable. The method comprises: acquiring the temperature measurement data of the temperature measuring unit; calculating the temperature error based on the temperature measurement data and the theoretical temperature of at least two thermal parameter sets, determining the thermal parameter set with the smallest temperature error as the target thermal parameter set; and obtaining the temperature field of the power cable according to the target thermal parameter set. On the one hand, the present invention solves the problems of high difficulty in measuring the core temperature and limited temperature measurement points in the prior art through theoretical calculation or simulation, thereby improving the comprehensiveness of the temperature field assessment results; on the other hand, the physical parameters of the power cable that are more in line with the actual situation are obtained through the determination of the thermal parameter set, thereby improving the accuracy of the temperature field assessment results.

Description

Technical Field

[0001] The present invention relates to the field of temperature assessment technology, and in particular to a method, system, device, medium and program for assessing the temperature field of a power cable. Background Art

[0002] Due to the diverse use environments of power cables, there are often different degrees of performance changes in different structural positions of power cables, which leads to a decrease in insulation performance and thermal conductivity, and the temperature distribution of power cables changes accordingly. Therefore, the abnormal temperature distribution of power cables is a precursor to failure, and accurate evaluation of the temperature field of power cables is an important way to ensure the safe operation of power cables.

[0003] At present, the temperature field assessment of power cables generally adopts real-time measurement. Temperature measuring optical fibers are arranged on the outer surface or inside of the power cables along the transmission direction of the power cables to monitor the temperature of the cable layer where the temperature measuring optical fibers are located. However, due to problems such as installation technology, the number of temperature measuring optical fibers arranged in power cables is limited. In addition, due to the heat resistance of optical fiber materials, it is difficult to directly measure the temperature of the cable core, and aging failures often start near the cable core.

[0004] It can be seen that the real-time measurement method based on temperature measuring optical fiber is difficult to accurately evaluate the temperature field of the cable. There are problems such as high difficulty in measuring the temperature of the core and limited temperature measurement points.

[0005] Therefore, how to evaluate the temperature field of power cables more accurately and comprehensively has become an issue that needs to be urgently addressed in the industry. Summary of the invention

[0006] The present invention provides a method, system, device, medium and program for evaluating the temperature field of a power cable, so as to solve the defects of the prior art in that the temperature measurement of the core is difficult and the temperature measurement points are limited, and realize accurate and comprehensive evaluation of the temperature field of the power cable.

[0007] The present invention provides a method for evaluating the temperature field of a power cable, which is used to evaluate the temperature field of a multi-layer power cable; the power cable comprises a core, a set number of layer structures and a set number of temperature measuring units; the layer structures are sequentially arranged on the core; the temperature measuring units are arranged on the surface or inside of the layer structures;

[0008] The power cable temperature field evaluation method comprises:

[0009] Acquiring temperature measurement data of the temperature measurement unit;

[0010] Calculating a temperature error based on the temperature measurement data and theoretical temperatures of at least two thermal parameter sets, and determining the thermal parameter set with the smallest temperature error as a target thermal parameter set; the thermal parameter set includes thermal parameters of the layer structure;

[0011] The temperature field of the power cable is obtained according to the target thermal parameter set.

[0012] According to a method for evaluating the temperature field of a power cable provided by the present invention, the theoretical temperature of the thermal parameter set includes the theoretical temperature of the temperature measuring unit under the thermal parameter set; the theoretical temperature of the i-th temperature measuring unit is based on the radial distance r of the i-th temperature measuring unit relative to the core axis. i , the thermal parameter set, the operating parameters of the power cable and the structural parameters of the power cable are calculated.

[0013] According to a method for evaluating a power cable temperature field provided by the present invention, the step of calculating a temperature error based on the temperature measurement data and a theoretical temperature of at least two thermal parameter sets comprises:

[0014] Based on the temperature measurement data of the i-th temperature measurement unit and the theoretical temperature of the i-th temperature measurement unit, the i-th temperature error factor is calculated;

[0015] The temperature error factor is summed based on the set weight to obtain the temperature error of the thermal parameter set.

[0016] According to a power cable temperature field evaluation method provided by the present invention, the i-th temperature error factor ΔT i satisfy:

[0017]

[0018] Where, t is time; T(r i ,t) is the temperature measurement data of the i-th temperature measurement unit at time t; T′(r i ,t) is the theoretical temperature of the i-th temperature measuring unit at time t under the thermal parameter set;

[0019] The temperature error satisfies:

[0020]

[0021] In the formula, ΔT(t a ~t b ) is t a From time t b i is the serial number of the temperature measuring unit; A is the number of the temperature measuring units; η i is the weight of the i-th temperature error factor.

[0022] According to a method for evaluating the temperature field of a power cable provided by the present invention, the theoretical temperature of the thermal parameter set is calculated based on the thermal parameter set, the operating parameters of the power cable and the structural parameters of the power cable, and the temperature field of the power cable;

[0023] The step of obtaining the temperature field of the power cable according to the target thermal parameter set comprises:

[0024] Determining a theoretical temperature of the target thermal parameter set;

[0025] The theoretical temperature of the target thermal parameter set is used as the temperature field of the power cable.

[0026] According to a method for evaluating the temperature field of a power cable provided by the present invention, the thermal parameter set is composed of the thermal conductivity of each layer structure; in different thermal parameter sets, there is at least one layer structure with different thermal conductivity; and the value range of the thermal conductivity of the layer structure is determined by an aging test.

[0027] The present invention also provides a power cable temperature field evaluation system for evaluating the temperature field of a multi-layer power cable; the power cable comprises a core, a set number of layer structures and a set number of temperature measuring units; the layer structures are sequentially arranged on the core; the temperature measuring units are arranged on the surface or inside of the layer structures;

[0028] The power cable temperature field evaluation system comprises:

[0029] An acquisition module, used to acquire the temperature measurement data of the temperature measurement unit;

[0030] an error module, configured to calculate a temperature error based on the temperature measurement data and theoretical temperatures of at least two thermal parameter sets, and determine the thermal parameter set with the smallest temperature error as a target thermal parameter set; the thermal parameter set includes thermal parameters of the layer structure;

[0031] A temperature field module is used to obtain the temperature field of the power cable according to the target thermal parameter set.

[0032] The present invention also provides an electronic device, 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 steps of any of the above-mentioned methods for evaluating the temperature field of a power cable are implemented.

[0033] The present invention also provides a non-transitory computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of any of the above-mentioned power cable temperature field evaluation methods are implemented.

[0034] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the steps of any of the above-mentioned methods for evaluating the temperature field of a power cable are implemented.

[0035] The power cable temperature field evaluation method, system, device, medium and program provided by the present invention determine the thermal parameters of the layer structure through the temperature measurement data of the temperature measuring unit, obtain the target thermal parameter set, and further obtain the temperature field of the power cable according to the target thermal parameter set. On the one hand, the problems of high difficulty in measuring the core temperature and limited temperature measurement points in the prior art are solved through theoretical calculation or simulation, thereby improving the comprehensiveness of the temperature field evaluation results; on the other hand, physical parameters of the power cable that are more in line with the actual situation are obtained by determining the thermal parameter set, thereby improving the accuracy of the temperature field evaluation results. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0037] Figure 1 It is a schematic diagram of the flow of the power cable temperature field evaluation method provided by the present invention;

[0038] Figure 2 It is a schematic diagram of the structure of a single-core power cable provided by an embodiment of the present invention;

[0039] Figure 3 This is a schematic diagram of the deployment of a single-core power cable temperature measurement optical fiber provided by an embodiment of the present invention;

[0040] Figure 4 It is a schematic diagram of a process for evaluating the temperature field of a ship power cable provided by an embodiment of the present invention;

[0041] Figure 5 It is a structural schematic diagram of the power cable temperature field evaluation system provided by the present invention;

[0042] Figure 6 It is a structural schematic diagram of the electronic device provided by the present invention.

[0043] Reference numerals:

[0044] 1: Acquisition module; 2: Error module; 3: Temperature field module;

[0045] 610: processor; 620: communication interface; 630: memory;

[0046] 640: Communication bus. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are 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] Combine the following Figure 1-Figure 4 The power cable temperature field evaluation method of the present invention is described.

[0049] like Figure 1 As shown, an embodiment of the present invention provides a method for evaluating the temperature field of a power cable, which is used to evaluate the temperature field of a multi-layer power cable; the power cable comprises a core, a set number of layer structures, and a set number of temperature measuring units; the layer structures are sequentially arranged on the core; the temperature measuring units are arranged on the surface or inside of the layer structures;

[0050] The power cable temperature field evaluation method comprises:

[0051] Step 101, obtaining temperature measurement data of the temperature measurement unit;

[0052] Step 103, calculating a temperature error based on the temperature measurement data and theoretical temperatures of at least two thermal parameter sets, and determining a thermal parameter set with a minimum temperature error as a target thermal parameter set; the thermal parameter set includes thermal parameters of the layer structure;

[0053] Step 105: obtaining the temperature field of the power cable according to the target thermal parameter set.

[0054] In this embodiment, the temperature measuring unit is arranged on the surface or inside of the layer structure, which refers to any one or any combination of the following arrangement schemes:

[0055] The temperature measuring unit is arranged on the outer surface of the layer structure;

[0056] The temperature measuring unit is arranged on the inner surface of the layer structure;

[0057] The temperature measuring unit is arranged inside the layer structure;

[0058] The temperature measuring unit is arranged between adjacent layer structures;

[0059] In a preferred embodiment, the temperature measuring unit is a temperature measuring optical fiber and / or a temperature sensor.

[0060] In a preferred embodiment, the layer structure includes any one or any combination of an insulating sheath layer, a metal sheath layer, an insulating layer, a shielding layer, and an insulating shielding layer;

[0061] In a preferred embodiment, the thermal parameter of the layer structure refers to the thermal parameter of the position where the temperature measuring unit is set in the layer structure, that is, the layer structure provided with multiple temperature measuring units may have multiple thermal parameters.

[0062] In a preferred embodiment, the thermal parameter set consists of the thermal conductivity of each layer structure; in different thermal parameter sets, at least one layer structure has a different thermal conductivity; and the value range of the thermal conductivity of the layer structure is determined by an aging test.

[0063] The beneficial effects of this embodiment are:

[0064] The thermal parameters of the layer structure are determined by the temperature measurement data of the temperature measurement unit, and the target thermal parameter set is obtained, and the temperature field of the power cable is further obtained based on the target thermal parameter set. On the one hand, the problems of high difficulty in measuring the core temperature and limited temperature measurement points in the prior art are solved through theoretical calculation or simulation, thereby improving the comprehensiveness of the temperature field evaluation results; on the other hand, physical parameters of the power cable that are more in line with the actual situation are obtained by determining the thermal parameter set, thereby improving the accuracy of the temperature field evaluation results.

[0065] According to the above embodiment, in this embodiment:

[0066] The theoretical temperature of the thermal parameter set is a temperature field of the power cable calculated based on the thermal parameter set, the operating parameters of the power cable and the structural parameters of the power cable;

[0067] The step of obtaining the temperature field of the power cable according to the target thermal parameter set comprises:

[0068] Determining a theoretical temperature of the target thermal parameter set;

[0069] The theoretical temperature of the target thermal parameter set is used as the temperature field of the power cable.

[0070] The beneficial effects of this embodiment are:

[0071] This embodiment further provides a method for calculating the theoretical temperature, that is, calculating through the thermal parameter set, the operating parameters of the power cable and the structural parameters of the power cable. This process can be both a physical calculation based on the electrical-thermal relationship and the principle of heat conduction, and a simulation calculation based on simulation software.

[0072] In the simulation calculation scheme, you can choose COMSOL Multiphysics, a temperature field finite element analysis software based on the traditional law of conservation of energy and Fourier's law of heat conduction, to perform temperature field simulation analysis of power cables. The input conditions include: operating parameters such as current, voltage, and frequency of the power cable, structural parameters such as the inner diameter, outer diameter, thickness, and cross-sectional area of ​​each layer of the power cable, and material parameters such as density, electrical conductivity, and thermal conductivity of each layer of the power cable.

[0073] Based on the method of this embodiment, on the one hand, the problems of high difficulty in measuring core temperature and limited temperature measurement points in the prior art are solved through theoretical calculation or simulation, thereby improving the comprehensiveness of the temperature field evaluation results; on the other hand, physical parameters of the power cable that are more in line with the actual situation are obtained by determining the thermal parameter set, thereby improving the accuracy of the temperature field evaluation results.

[0074] It is worth mentioning that if the target thermal parameter set is not determined through temperature measurement data, but the theoretical temperature is calculated only based on the original thermal parameters of the cable layer structure, the calculation result will be greatly distorted. The reason is that in harsh industrial environments, as the power cable gradually ages, the corresponding thermal conductivity of each layer of the cable will change significantly.

[0075] A feasible solution is to estimate the thermal conductivity of each layer of the power cable based on experience (the thermal conductivity of each layer of the in-service power cable cannot often be directly measured). However, due to the lack of accuracy of empirical estimates, this solution still has the problem of large errors in the calculation results.

[0076] according to Figure 1 Corresponding embodiment, in this embodiment:

[0077] The theoretical temperature of the thermal parameter set includes the theoretical temperature of the temperature measuring unit under the thermal parameter set; the theoretical temperature of the i-th temperature measuring unit is based on the radial distance r of the i-th temperature measuring unit relative to the core axis. i , the thermal parameter set, the operating parameters of the power cable and the structural parameters of the power cable are calculated.

[0078] The step of calculating the temperature error based on the temperature measurement data and the theoretical temperature of at least two thermal parameter sets comprises:

[0079] Based on the temperature measurement data of the i-th temperature measurement unit and the theoretical temperature of the i-th temperature measurement unit, the i-th temperature error factor is calculated;

[0080] The temperature error factor is summed based on the set weight to obtain the temperature error of the thermal parameter set.

[0081] The i-th temperature error factor ΔT i satisfy:

[0082]

[0083] Where, t is time; T(r i ,t) is the temperature measurement data of the i-th temperature measurement unit at time t; T′(r i ,t) is the theoretical temperature of the i-th temperature measuring unit at time t under the thermal parameter set;

[0084] The temperature error satisfies:

[0085]

[0086] In the formula, ΔT(t a ~t b ) is t a From time t b i is the serial number of the temperature measuring unit; A is the number of the temperature measuring units; η i is the weight of the i-th temperature error factor.

[0087] The beneficial effects of this embodiment are:

[0088] This embodiment provides a temperature field evaluation method based on discrete theoretical temperatures of a temperature measurement unit. Since the theoretical temperature is calculated based on a thermal parameter set, multiple thermal parameter sets need to calculate multiple theoretical temperatures accordingly.

[0089] This embodiment calculates the temperature error through the discrete theoretical temperature of the temperature measuring unit and the discrete temperature measurement data of the temperature measuring unit. Compared with the previous embodiment, the calculation process of the theoretical temperature is simplified, and the calculation of the theoretical temperature field is changed to the calculation of the discrete theoretical temperature, which further improves the efficiency of the temperature field evaluation process and the computing resource requirements.

[0090] A complete embodiment will be provided below based on the temperature field evaluation scenario of a ship power cable to better illustrate the solution of the present invention.

[0091] In different industrial scenarios, power cables are generally divided into single-core and multi-core. This embodiment takes a single-core power cable as an example. Figure 2 As shown, from inside to outside it includes a wire core, a shielding layer, an insulating layer, an insulating shielding layer, a metal sheath layer, and an outer sheath layer.

[0092] Figure 4 A schematic flow chart of the ship power cable temperature field evaluation of this embodiment is provided. Specifically, the method of this embodiment includes:

[0093] Step 1: Deployment and measurement of temperature measurement optical fiber;

[0094] Deploy temperature measurement optical fiber around single-core power cables, such as Figure 3 As shown, No. 1, No. 2 and No. 3 temperature measuring optical fibers are built-in optical fibers, arranged between the insulation layer and the insulation shielding layer, the insulation shielding layer and the metal sheath layer, and the metal sheath layer and the outer sheath layer, respectively; No. 4 temperature measuring optical fiber is an external optical fiber, arranged in close contact with the outer sheath layer. No. 1, No. 2, No. 3, and No. 4 temperature measuring optical fibers can monitor the temperature T(r1, t), T(r2, t), T(r3, t), and T(r4, t) of the cable at four radial positions in real time, where r1, r2, r3, and r4 are the radial positions of the four temperature measuring optical fibers.

[0095] Step 2: Input the temperature field finite element analysis software COMSOL Multiphysics;

[0096] For the temperature field finite element analysis software COMSOL Multiphysics, the input conditions mainly include the operating parameters of the power cable such as current, voltage, frequency, the structural parameters of each layer of the power cable such as the inner diameter, outer diameter, thickness and cross-sectional area, and the material parameters of each layer of the power cable such as density, electrical conductivity, and thermal conductivity. In harsh industrial environments, as the power cable gradually ages, the corresponding thermal conductivity of each layer of the cable will gradually decrease, which will have a great impact on the temperature field distribution of the power cable. However, the thermal conductivity of in-service power cables cannot be measured directly, and is generally estimated based on experience, which has certain errors, thus causing errors in the output. Therefore,

[0097] ε is defined as the thermal conductivity of the shielding layer of the power cable. Through aging test analysis, its threshold range is determined to be [ε a , ε b ];

[0098] σ is defined as the thermal conductivity of the insulation layer of the power cable. Through aging test analysis, its threshold range is determined to be [σ a , σ b ];

[0099] μ is defined as the thermal conductivity of the insulation shielding layer of the power cable. Through aging test analysis, its threshold range is determined to be [μ a , μ b ].

[0100] χ is defined as the thermal conductivity of the metal sheath layer of the power cable. Through aging test analysis, its threshold range is determined to be [χ a , χ b ].

[0101] Defined as the thermal conductivity of the outer sheath layer of the power cable, the threshold range is determined by aging test analysis.

[0102] Divide the threshold range into n segments, and adjust the thermal conductivity of the shielding layer, insulation layer, insulation shielding layer, metal sheath layer, and outer sheath layer in the input conditions in a step-by-step manner:

[0103] Thermal conductivity of the shielding layer of the power cable, including ε a ,

[0104] Thermal conductivity σ of the insulation layer of power cables, including σ a ,

[0105] Thermal conductivity μ of the insulation shielding layer of the power cable, including μ a ,

[0106] Thermal conductivity of the metal sheath layer of the power cable, including a ,

[0107] Thermal conductivity of the outer sheath of power cables include

[0108] The above five material parameters can be combined arbitrarily. Each material parameter has (n+1) combinations, for a total of (n+1) 5 A combination of methods.

[0109] Step 3: Calculation of temperature field using finite element analysis software COMSOL Multiphysics;

[0110] For (n+1) 5 For each input condition of the material parameter combination, the theoretical temperatures T′(r1,t), T′(r2,t), T′(r3,t), and T′(r4,t) at the radial positions r1, r2, r3, and r4 where the four temperature measuring optical fibers are located can be calculated based on the temperature field finite element analysis software COMSOL Multiphysics.

[0111] Step 4: High-precision temperature field determination;

[0112] For the four radial positions r1, r2, r3, and r4 in step 1, according to the temperature field finite element analysis software COMSOL Multiphysics calculation in step 3, we can get (n+1) 5 The theoretical temperatures of the four positions are T′(r1,t), T′(r2,t), T′(r3,t), and T′(r4,t).

[0113] In step 1, for the four radial position points, the measured temperatures T(r1, t), T(r2, t), T(r3, t), and T(r4, t) of the four position points are obtained based on actual measurements of the temperature measuring optical fiber.

[0114] For 4 position points, a period of time [t a , t b ], the error between the measured temperature and the theoretical temperature is recorded as:

[0115]

[0116] Therefore, a period of time [t a , t b ], for (n+1) 5 Theoretical power frequency electromagnetic field calculated by the temperature field finite element analysis software COMSOL Multiphysics, a total of (n+1) 5 The total error ΔT(t a ~t b ). Use the minimum comparator to determine the total error ΔT(t a ~t b ), the minimum value of the thermal conductivity combination of each layer of the power cable corresponding to this minimum value (ε z , σ z , μ z , χ z , ) is the optimal combination for this period of time. That is, the temperature field calculated by the temperature field finite element analysis software COMSOL Multiphysics using this combination as an input condition is a high-precision temperature field for this period of time, which can better match the actual measurement situation. Based on this high-precision temperature field, it can provide efficient support for the aging diagnosis and fault warning of power cables, and effectively ensure the safe operation of power cables.

[0117] The beneficial effects of this embodiment are:

[0118] This embodiment provides a power cable temperature field evaluation system based on the interaction of measured data. By integrating temperature field finite element analysis software with real-time measurement data, a high-precision temperature field distribution is established for the power cable, providing support for aging diagnosis and fault warning of the power cable.

[0119] The power cable temperature field evaluation device provided by the present invention is described below. The power cable temperature field evaluation device described below and the power cable temperature field evaluation method described above can be referred to each other.

[0120] The embodiment of the present invention further provides a power cable temperature field evaluation system, which is used to evaluate the temperature field of a multi-layer power cable; the power cable comprises a core, a set number of layer structures, and a set number of temperature measuring units; the layer structures are sequentially arranged on the core; the temperature measuring units are arranged on the surface or inside of the layer structures;

[0121] The power cable temperature field evaluation system comprises:

[0122] An acquisition module 1 is used to acquire the temperature measurement data of the temperature measurement unit;

[0123] An error module 2 is used to calculate a temperature error based on the temperature measurement data and theoretical temperatures of at least two thermal parameter sets, and determine the thermal parameter set with the smallest temperature error as a target thermal parameter set; the thermal parameter set includes thermal parameters of the layer structure;

[0124] The temperature field module 3 is used to obtain the temperature field of the power cable according to the target thermal parameter set.

[0125] The thermal parameter set is composed of the thermal conductivity of each layer structure; in different thermal parameter sets, at least one layer structure has a different thermal conductivity; and the value range of the thermal conductivity of the layer structure is determined by an aging test.

[0126] In a preferred embodiment, the temperature field module 3 includes:

[0127] A first unit is used to determine a theoretical temperature of the target thermal parameter set;

[0128] The second unit is configured to use the theoretical temperature of the target thermal parameter set as the temperature field of the power cable.

[0129] The theoretical temperature of the thermal parameter set is a temperature field of the power cable calculated based on the thermal parameter set, the operating parameters of the power cable and the structural parameters of the power cable;

[0130] In another preferred embodiment, the error module 2 includes:

[0131] A factor unit is used to calculate the i-th temperature error factor based on the temperature measurement data of the i-th temperature measurement unit and the theoretical temperature of the i-th temperature measurement unit;

[0132] A summing unit is used to sum the temperature error factors based on set weights to obtain the temperature error of the thermal parameter set.

[0133] The theoretical temperature of the thermal parameter set includes the theoretical temperature of the temperature measuring unit under the thermal parameter set; the theoretical temperature of the i-th temperature measuring unit is based on the radial distance r of the i-th temperature measuring unit relative to the core axis.i , the thermal parameter set, the operating parameters of the power cable and the structural parameters of the power cable are calculated.

[0134] The i-th temperature error factor ΔT i satisfy:

[0135]

[0136] Where, t is time; T(r i ,t) is the temperature measurement data of the i-th temperature measurement unit at time t; T′(r i ,t) is the theoretical temperature of the i-th temperature measuring unit at time t under the thermal parameter set;

[0137] The temperature error satisfies:

[0138]

[0139] In the formula, ΔT(t a ~t b ) is t a From time t b i is the serial number of the temperature measuring unit; A is the number of the temperature measuring units; η i is the weight of the i-th temperature error factor.

[0140] The beneficial effects of this embodiment are:

[0141] The thermal parameters of the layer structure are determined by the temperature measurement data of the temperature measurement unit, and the target thermal parameter set is obtained, and the temperature field of the power cable is further obtained based on the target thermal parameter set. On the one hand, the problems of high difficulty in measuring the core temperature and limited temperature measurement points in the prior art are solved through theoretical calculation or simulation, thereby improving the comprehensiveness of the temperature field evaluation results; on the other hand, physical parameters of the power cable that are more in line with the actual situation are obtained by determining the thermal parameter set, thereby improving the accuracy of the temperature field evaluation results.

[0142] Figure 6 An example of a physical structure diagram of an electronic device is shown in FIG. Figure 6As shown, the electronic device may include: a processor 610, a communication interface 620, a memory 630 and a communication bus 640, wherein the processor 610, the communication interface 620 and the memory 630 communicate with each other through the communication bus 640. The processor 610 may call the logic instructions in the memory 630 to execute the power cable temperature field evaluation method, which includes: obtaining the temperature measurement data of the temperature measurement unit; calculating the temperature error based on the temperature measurement data and the theoretical temperature of at least two thermal parameter sets, and determining the thermal parameter set with the minimum temperature error as the target thermal parameter set; the thermal parameter set includes the thermal parameters of the layer structure; and obtaining the temperature field of the power cable according to the target thermal parameter set.

[0143] In addition, the logic instructions in the above-mentioned memory 630 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0144] On the other hand, the present invention also provides a computer program product, which includes a computer program. The computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the power cable temperature field evaluation method provided by the above-mentioned methods, and the method includes: obtaining the temperature measurement data of the temperature measuring unit; calculating the temperature error based on the temperature measurement data and the theoretical temperature of at least two thermal parameter sets, and determining the thermal parameter set with the smallest temperature error as the target thermal parameter set; the thermal parameter set includes the thermal parameters of the layer structure; and obtaining the temperature field of the power cable according to the target thermal parameter set.

[0145] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the power cable temperature field evaluation method provided by the above-mentioned methods, the method comprising: obtaining temperature measurement data of the temperature measuring unit; calculating a temperature error based on the temperature measurement data and theoretical temperatures of at least two thermal parameter sets, and determining the thermal parameter set with the smallest temperature error as a target thermal parameter set; the thermal parameter set includes the thermal parameters of the layer structure; and obtaining the temperature field of the power cable according to the target thermal parameter set.

[0146] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0147] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0148] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for evaluating the temperature field of a power cable, characterized in that: Used to evaluate the temperature field of a multi-layer structure power cable; the power cable comprises a core, a set number of layer structures and a set number of temperature measuring units; The layer structures are sequentially arranged on the wire core; The temperature measuring unit is arranged on the surface or inside of the layer structure; The power cable temperature field evaluation method comprises: Acquiring temperature measurement data of the temperature measurement unit; Calculating a temperature error based on the temperature measurement data and theoretical temperatures of at least two thermal parameter sets, and determining the thermal parameter set with the smallest temperature error as a target thermal parameter set; the thermal parameter set includes thermal parameters of the layer structure; Obtaining a temperature field of the power cable according to the target thermal parameter set; The thermal parameter set is composed of the thermal conductivity of each layer structure; in different thermal parameter sets, at least one layer structure has a different thermal conductivity; and the value range of the thermal conductivity of the layer structure is determined by an aging test; The step of calculating the temperature error based on the temperature measurement data and the theoretical temperature of at least two thermal parameter sets includes: Based on the temperature measurement data of the i-th temperature measurement unit and the theoretical temperature of the i-th temperature measurement unit, the i-th temperature error factor is calculated; The temperature error factor is summed based on the set weight to obtain the temperature error of the thermal parameter set.

2. The power cable temperature field evaluation method according to claim 1, characterized in that: The theoretical temperature of the thermal parameter set includes the theoretical temperature of the temperature measuring unit under the thermal parameter set; The theoretical temperature of the ith temperature measuring unit is based on the radial distance r of the ith temperature measuring unit relative to the core axis. i , the thermal parameter set, the operating parameters of the power cable and the structural parameters of the power cable are calculated.

3. The power cable temperature field evaluation method according to claim 1, characterized in that: The i-th temperature error factor ΔT i satisfy: Where, t is time; T(r i ,t) is the temperature measurement data of the i-th temperature measurement unit at time t; T ′ (r i ,t) is the theoretical temperature of the i-th temperature measuring unit at time t under the thermal parameter set; The temperature error satisfies: In the formula, ΔT(t a ~t b ) is t a From time t b i is the serial number of the temperature measuring unit; A is the number of the temperature measuring units; η i is the weight of the i-th temperature error factor.

4. The power cable temperature field evaluation method according to claim 1, characterized in that: The theoretical temperature of the thermal parameter set is a temperature field of the power cable calculated based on the thermal parameter set, the operating parameters of the power cable and the structural parameters of the power cable; The step of obtaining the temperature field of the power cable according to the target thermal parameter set comprises: Determining a theoretical temperature of the target thermal parameter set; The theoretical temperature of the target thermal parameter set is used as the temperature field of the power cable.

5. A power cable temperature field evaluation system, characterized in that: Used to evaluate the temperature field of a multi-layer structure power cable; the power cable comprises a core, a set number of layer structures and a set number of temperature measuring units; The layer structures are sequentially arranged on the wire core; The temperature measuring unit is arranged on the surface or inside of the layer structure; The power cable temperature field evaluation system comprises: An acquisition module, used to acquire the temperature measurement data of the temperature measurement unit; an error module, configured to calculate a temperature error based on the temperature measurement data and theoretical temperatures of at least two thermal parameter sets, and determine the thermal parameter set with the smallest temperature error as a target thermal parameter set; the thermal parameter set includes thermal parameters of the layer structure; A temperature field module, used for obtaining the temperature field of the power cable according to the target thermal parameter set; The thermal parameter set is composed of the thermal conductivity of each layer structure; in different thermal parameter sets, at least one layer structure has a different thermal conductivity; and the value range of the thermal conductivity of the layer structure is determined by an aging test; Wherein, the error module is specifically used for: Based on the temperature measurement data of the i-th temperature measurement unit and the theoretical temperature of the i-th temperature measurement unit, the i-th temperature error factor is calculated; The temperature error factor is summed based on the set weight to obtain the temperature error of the thermal parameter set.

6. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the steps of the power cable temperature field evaluation method according to any one of claims 1 to 4 are implemented.

7. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the power cable temperature field evaluation method according to any one of claims 1 to 4 are implemented.

8. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the power cable temperature field evaluation method according to any one of claims 1 to 4 are implemented.

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