A method, device, equipment and storage medium for calculating the core temperature of a high-voltage cable

By constructing a transient thermal circuit model of an equivalent high-voltage cable and combining historical and real-time temperature data, the cable core temperature can be quickly calculated, solving the problem of low calculation efficiency in existing technologies and ensuring the safety and stability of the power system.

CN119578099BActive Publication Date: 2025-10-03GUANGDONG POWER GRID CO LTD +1
View PDF 2 Cites 0 Cited by

Patent Information

Application Number
CN202411736433.3
Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
Filing Date
2024-11-29
Publication Date
2025-10-03
Estimated Expiration
2044-11-29

AI Technical Summary

Technical Problem

Existing technologies are inefficient in calculating the core temperature of high-voltage cables, take a long time, and are unable to quickly obtain accurate temperature data, affecting the safe and stable operation of the power system.

Method used

A transient thermal circuit model is constructed based on the structural composition of the high-voltage cable, and is equivalent to a first-order transient equivalent thermal circuit model. Using historical temperature data and real-time cable surface temperature, the equivalent thermal resistance and heat capacity are solved by fitting and differential methods to quickly calculate the cable core temperature.

Benefits of technology

By simplifying the thermal circuit model and real-time temperature acquisition, the high-voltage cable core temperature can be quickly calculated, which improves the calculation efficiency and ensures the safe and stable operation of the power system.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure CN119578099B_ABST
    Figure CN119578099B_ABST
Patent Text Reader

Abstract

The present invention discloses a method, device, equipment and storage medium for calculating the cable core temperature of a high-voltage cable. A transient thermal circuit model of the high-voltage cable is constructed based on the structural composition of the high-voltage cable, the transient thermal circuit model of the high-voltage cable is equivalent to a first-order transient equivalent thermal circuit model, the equivalent thermal resistance and equivalent thermal capacity of the first-order transient equivalent thermal circuit model are solved based on historical temperature data, the real-time collected cable surface temperature is obtained, and the cable core temperature of the high-voltage cable is calculated based on the cable surface temperature, the equivalent thermal resistance and the equivalent thermal capacity. By equating the transient thermal circuit model of the high-voltage cable to a first-order transient equivalent thermal circuit model and solving the equivalent thermal resistance and equivalent thermal capacity of the first-order transient equivalent thermal circuit model based on historical temperature data, in practical applications, the cable core temperature of the high-voltage cable can be quickly calculated based on the real-time collected cable surface temperature and the solved first-order transient equivalent thermal circuit model, thereby improving the efficiency of cable core temperature calculation.
Need to check novelty before this filing date? Find Prior Art

Description

Technical Field

[0001] The present invention relates to electric power technology, and in particular to a method, device, equipment and storage medium for calculating the cable core temperature of a high-voltage cable. Background Art

[0002] In power systems, high-voltage cables carry the bulk of the current. Current flowing through the cables creates a certain resistance, causing the cables to heat up. Excessively high cable temperatures can shorten cable life, degrade performance, and even lead to safety incidents. Therefore, determining the core temperature of high-voltage cables is crucial to ensure the safe and stable operation of power systems.

[0003] Determining cable core temperature primarily relies on the thermal circuit model. The thermal circuit model stems from the electrothermal similarity theory. Analogous to the concepts of power supply, voltage, and electrical parameters (resistance, capacitance, and inductance) in an electrical circuit, the thermal circuit model consists of three key elements: heat source, temperature, and thermal parameters. Knowing the values ​​of two of these elements allows the value of the other to be determined. Generally speaking, the heat source can be calculated based on the current flow through the cable and related electrical parameters. Once the cable's thermal parameters are known, the cable core temperature can be determined.

[0004] Currently, cable thermal parameters (including thermal resistance and thermal capacitance) are typically calculated based on experimental results. For the thermal resistance parameter, the cable must be heated to a steady-state temperature before the resulting data can be used for calculation, a time-consuming process. Furthermore, only after the thermal resistance parameter is determined can the thermal capacitance parameter be calculated using transient data. Consequently, existing methods are time-consuming and computationally inefficient. Summary of the Invention

[0005] The present invention provides a method, device, equipment and storage medium for calculating the cable core temperature of a high-voltage cable, so as to improve the efficiency of calculating the cable core temperature.

[0006] In a first aspect, the present invention provides a method for calculating the core temperature of a high-voltage cable, comprising:

[0007] Constructing a transient thermal circuit model of the high-voltage cable based on the structural composition of the high-voltage cable;

[0008] Equivalently converting the transient thermal circuit model of the high-voltage cable into a first-order transient equivalent thermal circuit model;

[0009] Solving the equivalent thermal resistance and equivalent heat capacity of the first-order transient equivalent thermal circuit model based on the historical temperature data;

[0010] Obtain the real-time collected cable surface temperature;

[0011] The core temperature of the high-voltage cable is calculated based on the cable surface temperature, the equivalent thermal resistance, and the equivalent thermal capacity.

[0012] Optionally, the high-voltage cable includes a cable core, an insulation layer wrapping the cable core, a buffer layer wrapping the insulation layer, an aluminum sheath wrapping the buffer layer, and an outer sheath wrapping the aluminum sheath. Constructing a transient thermal circuit model of the high-voltage cable based on the structural composition of the high-voltage cable includes:

[0013] Construct a transient thermal circuit model of the cable core heating power with respect to the cable core temperature, cable core heat capacity, insulation heat loss, insulation layer temperature, insulation layer heat capacity, insulation layer thermal resistance, buffer layer heat loss, buffer layer thermal resistance, buffer layer heat capacity, aluminum sheath heat loss, aluminum sheath temperature, aluminum sheath heat capacity, outer sheath temperature, outer sheath thermal resistance and outer sheath heat capacity.

[0014] Optionally, the transient thermal circuit model of the high-voltage cable is equivalent to a first-order transient equivalent thermal circuit model, including:

[0015] The transient thermal circuit model of the high-voltage cable is equivalent to a first-order transient equivalent thermal circuit model of the cable core heating power with respect to the cable core temperature, the temperature of the outer sheath, the equivalent heat capacity and the equivalent thermal resistance.

[0016] Optionally, the first-order transient equivalent thermal circuit model is as follows:

[0017]

[0018] Where Q is the heating power of the cable core, θ c is the cable core temperature, θ o is the temperature of the outer sheath, C is the equivalent heat capacity, and T is the equivalent thermal resistance.

[0019] Optionally, solving the equivalent thermal resistance and equivalent heat capacity of the first-order transient equivalent thermal circuit model based on the historical temperature data includes:

[0020] Substituting the first historical cable core temperature and the first historical cable surface temperature at the first acquisition moment into the first-order transient equivalent heat circuit model to obtain a first transient equivalent heat circuit equation;

[0021] Substituting the second historical cable core temperature and the second historical cable surface temperature at the second acquisition moment into the first-order transient equivalent heat circuit model to obtain a second transient equivalent heat circuit equation;

[0022] The first transient equivalent heat circuit equation and the second transient equivalent heat circuit equation are combined to solve the equivalent thermal resistance and equivalent heat capacity of the first-order transient equivalent heat circuit model.

[0023] Optionally, the first transient equivalent heat circuit equation and the second transient equivalent heat circuit equation are combined to solve the equivalent thermal resistance and equivalent heat capacity of the first-order transient equivalent heat circuit model, including:

[0024] The transient temperature equation of the cable core is described by the fitting method, and the function of the transient temperature of the cable core with respect to time is determined;

[0025] Differentiating the transient temperature of the cable core as a function of time to obtain a differential expression of the transient temperature of the cable core with respect to time;

[0026] Substitute the differential expression of the transient temperature of the cable core with respect to time into the first transient equivalent heat circuit equation and the second transient equivalent heat circuit equation to solve the equivalent thermal resistance and equivalent heat capacity of the first-order transient equivalent heat circuit model.

[0027] Optionally, the transient temperature of the cable core as a function of time is:

[0028]

[0029] The differential expression of the transient temperature of the cable core with respect to time is:

[0030]

[0031] Among them, x1, x2, x3 are fitting coefficients, and t is time.

[0032] In a second aspect, the present invention further provides a device for calculating the core temperature of a high-voltage cable, comprising:

[0033] A thermal circuit model building module, configured to build a transient thermal circuit model of the high-voltage cable based on the structural composition of the high-voltage cable;

[0034] A model equivalent module, used to convert the transient thermal circuit model of the high-voltage cable into a first-order transient equivalent thermal circuit model;

[0035] a parameter solving module, configured to solve the equivalent thermal resistance and equivalent heat capacity of the first-order transient equivalent thermal circuit model based on the historical temperature data;

[0036] Real-time temperature acquisition module, used to obtain the real-time collected cable surface temperature;

[0037] A cable core temperature calculation module is used to calculate the cable core temperature of the high-voltage cable based on the cable surface temperature, the equivalent thermal resistance and the equivalent heat capacity.

[0038] In a third aspect, the present invention further provides an electronic device, comprising:

[0039] one or more processors;

[0040] a storage device for storing one or more programs;

[0041] When the one or more programs are executed by the one or more processors, the one or more processors implement the method for calculating the core temperature of a high-voltage cable as provided in the first aspect of the present invention.

[0042] In a fourth aspect, the present invention further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method for calculating the core temperature of a high-voltage cable as provided in the first aspect of the present invention.

[0043] The present invention provides a method for calculating the cable core temperature of a high-voltage cable. The method constructs a transient thermal circuit model of the high-voltage cable based on the structural composition of the high-voltage cable, equates the transient thermal circuit model of the high-voltage cable to a first-order transient equivalent thermal circuit model, solves the equivalent thermal resistance and equivalent thermal capacity of the first-order transient equivalent thermal circuit model based on historical temperature data, obtains the real-time collected cable surface temperature, and calculates the cable core temperature of the high-voltage cable based on the cable surface temperature, the equivalent thermal resistance and the equivalent thermal capacity. By equating the transient thermal circuit model of the high-voltage cable to a first-order transient equivalent thermal circuit model, and solving the equivalent thermal resistance and equivalent thermal capacity of the first-order transient equivalent thermal circuit model based on historical temperature data, in actual application, the cable core temperature of the high-voltage cable can be quickly calculated according to the real-time collected cable surface temperature and the solved first-order transient equivalent thermal circuit model, thereby improving the efficiency of cable core temperature calculation.

[0044] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0046] Figure 1 A flow chart of a method for calculating the cable core temperature of a high-voltage cable provided by the present invention;

[0047] Figure 2 A circuit diagram of a transient thermal circuit model of a high-voltage cable provided by the present invention;

[0048] Figure 3 A circuit diagram of a first-order transient equivalent thermal circuit model provided by the present invention;

[0049] Figure 4 A schematic structural diagram of a device for calculating the core temperature of a high-voltage cable provided by the present invention;

[0050] Figure 5 This is a structural diagram of an electronic device provided by the present invention.

[0051] The above drawings illustrate specific embodiments of the present application, which will be described in more detail below. These drawings and the textual description are not intended to limit the scope of the present application in any way, but rather to illustrate the concepts of the present application to those skilled in the art by reference to specific embodiments. DETAILED DESCRIPTION

[0052] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0053] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0054] Figure 1 This is a flow chart of a method for calculating the cable core temperature of a high-voltage cable provided by the present invention. This embodiment is applicable to the case of quickly calculating the cable core temperature of a high-voltage cable. The method can be executed by a device for calculating the cable core temperature of a high-voltage cable provided by an embodiment of the present invention. The device can be implemented by software and / or hardware and is usually configured in an electronic device, such as Figure 1 As shown in FIG, the method for calculating the core temperature of a high-voltage cable specifically includes the following steps:

[0055] S101. Construct a transient thermal circuit model of the high-voltage cable based on the structural composition of the high-voltage cable.

[0056] In an embodiment of the present invention, a transient thermal circuit model of a high-voltage cable is constructed based on the structural composition of the high-voltage cable. In power cables, the transient thermal circuit model is used to describe the temperature distribution and heat flow changes of the cable under different working conditions. Exemplarily, the structural composition of a high-voltage cable refers to the layer structure of the high-voltage cable. Typically, a high-voltage cable includes a cable core and other layer structures covering the cable core, such as an insulation layer, a protective layer, etc., which is not limited in the embodiment of the present invention. The heat generated by the cable core of the high-voltage cable is transferred outward layer by layer through the layer structure, thereby constructing a transient thermal circuit model of the high-voltage cable.

[0057] Exemplarily, in some embodiments of the present invention, the high-voltage cable includes a cable core, an insulation layer wrapping the cable core, a buffer layer wrapping the insulation layer, an aluminum sheath wrapping the buffer layer, and an outer sheath wrapping the aluminum sheath, and a transient thermal circuit model of the cable core heating power is constructed with respect to the cable core temperature, cable core heat capacity, insulation heat loss, insulation layer temperature, insulation layer heat capacity, insulation layer thermal resistance, buffer layer heat loss, buffer layer thermal resistance, buffer layer heat capacity, aluminum sheath heat loss, aluminum sheath temperature, aluminum sheath heat capacity, outer sheath temperature, outer sheath thermal resistance, and outer sheath heat capacity.

[0058] Figure 2 A circuit diagram of a transient thermal circuit model of a high-voltage cable provided by the present invention, such as Figure 2 As shown in the figure, the transient thermal model circuit of the high-voltage cable includes the transient thermal model circuit of the cable core, the transient thermal model circuit of the insulation layer (usually cross-linked polyethylene (XLPE)), the transient thermal model circuit of the buffer layer, the transient thermal model circuit of the aluminum sheath and the transient thermal model circuit of the outer sheath. These circuits are in parallel. c ,θ i ,θ s ,θ o They are respectively the cable core temperature, the insulation layer temperature, the aluminum sheath temperature, and the outer sheath temperature, in °C; T i 、T b 、T o are the thermal resistance of the insulation layer, the thermal resistance of the buffer layer, and the thermal resistance of the outer sheath, in K·m / W; C c is the heat capacity of the cable core, in J / (m·K); C i1 、C i2 are the distributed heat capacity of the insulation layer, in J / (m·K); C b is the heat capacity of the buffer layer, in J / (m·K); C s is the heat capacity of the aluminum sheath, in J / (m·K); C o is the heat capacity of the outer sheath, in J / (m·K); Q1 is the heating power of the cable core, in W / m; Q2 and Q3 are the heat loss of the insulation layer, in W / m; Q4 is the heat loss of the aluminum sheath, in W / m.

[0059] S102. Equivalent the transient thermal circuit model of the high-voltage cable to a first-order transient equivalent thermal circuit model.

[0060] Exemplarily, the transient thermal circuit model of the high-voltage cable is equivalent to a first-order transient equivalent thermal circuit model of the cable core heating power with respect to the cable core temperature, the temperature of the outer sheath, the equivalent heat capacity and the equivalent thermal resistance. Figure 3 A circuit diagram of a first-order transient equivalent thermal circuit model provided by the present invention, such as Figure 3 As shown in the figure, the simplified principle of analog circuit can simplify the circuit of the transient thermal circuit model of the cable into a first-order thermal circuit model. In the figure: C is the equivalent heat capacitance, T is the equivalent thermal resistance, and Q is the equivalent heat source.

[0061] The corresponding relationship between the three equivalent parameters and the parameters in the original transient thermal circuit model can be characterized according to equations (1)-(3):

[0062] Q=Q1 (1)

[0063] T=T i +T b +T o (2)

[0064]

[0065] It can be seen that the equivalent parameters of the cable have a corresponding relationship with the original transient thermal circuit model. Solving the equivalent parameters of the first-order transient equivalent thermal circuit can also characterize the transient thermal process of the cable.

[0066] according to Figure 3 The circuit diagram of the first-order transient equivalent thermal circuit model is shown in FIG. 4 , and the mathematical expression of the first-order transient equivalent thermal circuit model of the cable can be written as shown in (4):

[0067]

[0068] Where Q is the heating power of the cable core, θ c is the cable core temperature, θ o is the temperature of the outer sheath, C is the equivalent heat capacity, and T is the equivalent thermal resistance. The cable core heating power Q can be calculated according to the IEC 60287 standard, while the equivalent heat capacity C and equivalent thermal resistance T are unknown quantities.

[0069] S103. Solve the equivalent thermal resistance and equivalent heat capacity of the first-order transient equivalent thermal circuit model based on historical temperature data.

[0070] Since the first-order transient equivalent thermal circuit model of the cable can be written at any time during the temperature change process of the cable, the equivalent thermal parameter solution equations can be written at two temperature points during the temperature change process of the cable. The first historical cable core temperature and the first historical cable surface temperature at the first acquisition time numbered N1 and N2 in the historical acquisition data, as well as the second historical cable core temperature and the second historical cable surface temperature at the second acquisition time are analyzed. The written equations are shown in Equation (5):

[0071]

[0072] Where: θ cN1 is the temperature data of the cable core numbered N1; θ oN1 is the surface temperature data of the outer sheath numbered N1; θ cN2 is the temperature data of the cable core numbered N2; θ oN2 is the temperature data of the outer sheath numbered N2; Q N1 is the heating power of the cable at the time corresponding to N1; Q N2 is the heating power of the cable at the time corresponding to number N2.

[0073] Since the temperature differential term of the cable core cannot be measured directly, the present invention considers using analytical derivation to solve the temperature differential term. During the processing, the transient temperature equation of the cable core is described by a fitting method. The fitted transient equation of the cable core satisfies formula (6):

[0074]

[0075] It is a function of time, x1, x2, x3 are fitting coefficients, and t is time.

[0076] The three fitting coefficients can be solved based on the actual temperature rise data of the cable collected, and the differential term of the cable core can be expressed as follows:

[0077]

[0078] Therefore, as long as the time corresponding to a certain temperature point is obtained, the temperature differential term corresponding to the temperature point can also be solved.

[0079] Therefore, by substituting the first acquisition time numbered N1 into formula (7) and the second acquisition time numbered N2 into formula (7), we can obtain formula (8):

[0080]

[0081] Among them, k 1_N1 Substituting the first acquisition moment numbered N1 into formula (7) to calculate the temperature differential term at the first acquisition moment, k2_N1 is the temperature difference between the cable core and the outer sheath at the first acquisition moment numbered N1, k 1_N2 Substituting the second acquisition time numbered N2 into formula (7) to calculate the temperature differential term at the second acquisition time, k 2_N2 is the temperature difference between the cable core temperature and the outer sheath temperature at the second acquisition moment numbered N2.

[0082] Substituting the above (8) into formula (5) to solve the equivalent thermal resistance and equivalent heat capacity of the first-order transient equivalent thermal circuit model, the expressions of the equivalent thermal resistance T and equivalent heat capacity C are obtained as follows:

[0083]

[0084] Among them, Q N1 is the heating power of the cable at the first acquisition moment numbered N1, Q N2 It is the heating power of the cable at the second collection moment numbered N2.

[0085] S104: Acquire the cable surface temperature collected in real time.

[0086] In actual application, the cable surface temperature, that is, the temperature of the outer sheath, is collected in real time. For example, a temperature sensor can be provided on the outer sheath to collect the temperature of the outer sheath.

[0087] S105. Calculate the core temperature of the high-voltage cable based on the cable surface temperature, equivalent thermal resistance, and equivalent heat capacity.

[0088] For example, the cable surface temperature collected in real time is substituted into the first-order transient equivalent thermal circuit model for calculation to obtain the cable core temperature of the high-voltage cable. Since the equivalent thermal resistance T, equivalent heat capacity C, and temperature differential terms of the first-order transient equivalent thermal circuit model have been solved, the cable core heating power Q can be calculated according to the IEC 60287 standard. Therefore, only the cable core temperature θ c An unknown quantity, therefore, the cable core temperature θ can be directly calculated c .

[0089] The present invention provides a method for calculating the cable core temperature of a high-voltage cable. The method constructs a transient thermal circuit model of the high-voltage cable based on the structural composition of the high-voltage cable, equates the transient thermal circuit model of the high-voltage cable to a first-order transient equivalent thermal circuit model, solves the equivalent thermal resistance and equivalent thermal capacity of the first-order transient equivalent thermal circuit model based on historical temperature data, obtains the real-time collected cable surface temperature, and calculates the cable core temperature of the high-voltage cable based on the cable surface temperature, the equivalent thermal resistance and the equivalent thermal capacity. By equating the transient thermal circuit model of the high-voltage cable to a first-order transient equivalent thermal circuit model, and solving the equivalent thermal resistance and equivalent thermal capacity of the first-order transient equivalent thermal circuit model based on historical temperature data, in actual application, the cable core temperature of the high-voltage cable can be quickly calculated according to the real-time collected cable surface temperature and the solved first-order transient equivalent thermal circuit model, thereby improving the efficiency of cable core temperature calculation.

[0090] Figure 4 A schematic diagram of the structure of a high-voltage cable core temperature calculation device provided by the present invention is shown as follows: Figure 4 As shown, the cable core temperature calculation device of the high-voltage cable includes:

[0091] A thermal circuit model building module 201 is configured to build a transient thermal circuit model of the high-voltage cable based on the structural composition of the high-voltage cable;

[0092] A model equivalent module 202 is used to convert the transient thermal circuit model of the high-voltage cable into a first-order transient equivalent thermal circuit model;

[0093] A parameter solving module 203 is configured to solve the equivalent thermal resistance and equivalent heat capacity of the first-order transient equivalent thermal circuit model based on the historical temperature data;

[0094] The real-time temperature acquisition module 204 is used to obtain the cable surface temperature collected in real time;

[0095] The cable core temperature calculation module 205 is configured to calculate the cable core temperature of the high-voltage cable based on the cable surface temperature, the equivalent thermal resistance, and the equivalent thermal capacity.

[0096] In some embodiments of the present invention, the high-voltage cable includes a cable core, an insulation layer wrapping the cable core, a buffer layer wrapping the insulation layer, an aluminum sheath wrapping the buffer layer, and an outer sheath wrapping the aluminum sheath, and the thermal circuit model construction module 201 includes:

[0097] The thermal circuit model construction submodule is used to construct a transient thermal circuit model of the cable core heating power with respect to the cable core temperature, cable core heat capacity, insulation heat loss, insulation layer temperature, insulation layer heat capacity, insulation layer thermal resistance, buffer layer heat loss, buffer layer thermal resistance, buffer layer heat capacity, aluminum sheath heat loss, aluminum sheath temperature, aluminum sheath heat capacity, outer sheath temperature, outer sheath thermal resistance and outer sheath heat capacity.

[0098] In some embodiments of the present invention, the model equivalence module 202 includes:

[0099] The model equivalent submodule is used to equate the transient thermal circuit model of the high-voltage cable to a first-order transient equivalent thermal circuit model of the cable core heating power with respect to the cable core temperature, the temperature of the outer sheath, the equivalent heat capacity and the equivalent thermal resistance.

[0100] In some embodiments of the present invention, the first-order transient equivalent thermal circuit model is as follows:

[0101]

[0102] Where Q is the heating power of the cable core, θ c is the cable core temperature, θ o is the temperature of the outer sheath, C is the equivalent heat capacity, and T is the equivalent thermal resistance.

[0103] In some embodiments of the present invention, the parameter solving module 203 includes:

[0104] a first heat circuit equation construction submodule, configured to substitute the first historical cable core temperature and the first historical cable surface temperature at the first acquisition moment into the first-order transient equivalent heat circuit model to obtain a first transient equivalent heat circuit equation;

[0105] A second heat circuit equation construction submodule is used to substitute the second historical cable core temperature and the second historical cable surface temperature at the second acquisition moment into the first-order transient equivalent heat circuit model to obtain a second transient equivalent heat circuit equation;

[0106] The simultaneous solving submodule is used to simultaneously solve the first transient equivalent thermal circuit equation and the second transient equivalent thermal circuit equation to solve the equivalent thermal resistance and equivalent thermal capacity of the first-order transient equivalent thermal circuit model.

[0107] In some embodiments of the present invention, the simultaneous solution submodule includes:

[0108] A fitting unit is used to describe the transient temperature equation of the cable core using a fitting method, and determine the function of the transient temperature of the cable core with respect to time;

[0109] A differential unit, configured to differentiate the transient temperature of the cable core as a function of time to obtain a differential expression of the transient temperature of the cable core as a function of time;

[0110] A solving unit is used to substitute the differential expression of the transient temperature of the cable core with respect to time into the first transient equivalent heat circuit equation and the second transient equivalent heat circuit equation to solve the equivalent thermal resistance and equivalent heat capacity of the first-order transient equivalent heat circuit model.

[0111] In some embodiments of the present invention, the transient temperature of the cable core as a function of time is:

[0112]

[0113] The differential expression of the transient temperature of the cable core with respect to time is:

[0114]

[0115] Among them, x1, x2, x3 are fitting coefficients, and t is time.

[0116] The above-mentioned device for calculating the core temperature of a high-voltage cable can execute the method for calculating the core temperature of a high-voltage cable provided in the above-mentioned embodiment of the present invention, and has corresponding functional modules and beneficial effects for executing the method for calculating the core temperature of a high-voltage cable.

[0117] Figure 5 A schematic diagram of the structure of an electronic device provided by the present invention. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device may also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or claimed herein.

[0118] like Figure 5 As shown, the electronic device includes at least one processor 11 and a memory, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc., which is communicatively connected to the at least one processor 11. The memory stores a computer program that can be executed by the at least one processor, and the processor 11 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 into the random access memory (RAM) 13. Various programs and data required for the operation of the electronic device can also be stored in the RAM 13. The processor 11, ROM 12, and RAM 13 are connected to each other via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0119] Multiple components in the electronic device are connected to the I / O interface 15, including an input unit 16, such as a keyboard, mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a magnetic disk, optical disk, etc.; and a communication unit 19, such as a network card, modem, wireless communication transceiver, etc. The communication unit 19 allows the electronic device to exchange information / data with other devices via a computer network such as the Internet and / or various telecommunication networks.

[0120] The processor 11 can be any general-purpose and / or specialized processing component with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various specialized artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, such as the method for calculating the core temperature of a high-voltage cable.

[0121] In some embodiments, the method for calculating the core temperature of a high-voltage cable can be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 18. In some embodiments, part or all of the computer program can be loaded and / or installed on the electronic device via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of the method for calculating the core temperature of a high-voltage cable described above can be performed. Alternatively, in other embodiments, the processor 11 can be configured to execute the method for calculating the core temperature of a high-voltage cable by any other appropriate means (e.g., by means of firmware).

[0122] Various embodiments of the systems and techniques described herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), system-on-chip systems (SOCs), programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments can include being implemented in one or more computer programs that are executable and / or interpreted on a programmable system that includes at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0123] Computer programs for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when the computer program is executed by the processor, the functions / operations specified in the flowcharts and / or block diagrams are implemented. The computer program may be executed entirely on the machine, partially on the machine, as a stand-alone software package, partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0124] In the context of the present invention, computer-readable storage media can be tangible media that can contain or store a computer program for use with an instruction execution system, device or equipment or used in combination with an instruction execution system, device or equipment. Computer-readable storage media can include but are not limited to electronic, magnetic, optical, electromagnetic, infrared or semiconductor systems, devices or equipment, or any suitable combination of the foregoing. Alternatively, computer-readable storage media can be machine-readable signal media. More specific examples of machine-readable storage media can include electrical connections based on one or more lines, portable computer disks, hard disks, random access memories (RAM), read-only memories (ROM), erasable programmable read-only memories (EPROM or flash memory), optical fibers, portable compact disk read-only memories (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0125] To provide interaction with a user, the systems and techniques described herein can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user can provide input to the electronic device. Other types of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic input, voice input, or tactile input).

[0126] The systems and techniques described herein can be implemented in a computing system that includes back-end components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes front-end components (e.g., a user computer with a graphical user interface or web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such back-end components, middleware components, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0127] A computing system may include clients and servers. The clients and servers are typically remote from each other and typically interact via a communication network. This client-server relationship arises through computer programs running on the respective computers, creating a client-server relationship. The server may be a cloud server, also known as a cloud computing server or cloud host. This server is a hosting product within the cloud computing service ecosystem that addresses the management difficulties and limited scalability of traditional physical hosting and VPS services.

[0128] An embodiment of the present invention further provides a computer program product, including a computer program, which, when executed by a processor, implements the method for calculating the core temperature of a high-voltage cable as provided in any embodiment of the present application.

[0129] The computer program product may be implemented by writing computer program code for performing the operations of the present invention in one or more programming languages, or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a stand-alone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0130] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in the present invention can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution of the present invention can be achieved. This is not limited herein.

[0131] The above specific embodiments do not limit the scope of protection of the present invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A method for calculating the core temperature of a high-voltage cable, characterized in that: include: Constructing a transient thermal circuit model of the high-voltage cable based on the structural composition of the high-voltage cable; Equivalently converting the transient thermal circuit model of the high-voltage cable into a first-order transient equivalent thermal circuit model; Solving the equivalent thermal resistance and equivalent heat capacity of the first-order transient equivalent thermal circuit model based on historical temperature data; Obtain the real-time collected cable surface temperature; Calculating the core temperature of the high-voltage cable based on the cable surface temperature, the equivalent thermal resistance and the equivalent heat capacity; The high-voltage cable includes a cable core, an insulation layer wrapping the cable core, a buffer layer wrapping the insulation layer, an aluminum sheath wrapping the buffer layer, and an outer sheath wrapping the aluminum sheath. A transient thermal circuit model of the high-voltage cable is constructed based on the structural composition of the high-voltage cable, including: Construct a transient thermal circuit model of the cable core heating power with respect to the cable core temperature, cable core heat capacity, insulation heat loss, insulation layer temperature, insulation layer heat capacity, insulation layer thermal resistance, buffer layer heat loss, buffer layer thermal resistance, buffer layer heat capacity, aluminum sheath heat loss, aluminum sheath temperature, aluminum sheath heat capacity, outer sheath temperature, outer sheath thermal resistance and outer sheath heat capacity; The transient thermal circuit model of the high-voltage cable is equivalent to a first-order transient equivalent thermal circuit model, including: Equivalently converting the transient thermal circuit model of the high-voltage cable into a first-order transient equivalent thermal circuit model of the cable core heating power with respect to the cable core temperature, the temperature of the outer sheath, the equivalent heat capacity and the equivalent thermal resistance; The first-order transient equivalent thermal circuit model is as follows: in, is the heating power of the cable core, is the cable core temperature, is the temperature of the outer sheath, is the equivalent heat capacity, is the equivalent thermal resistance.

2. The method for calculating the core temperature of a high-voltage cable according to claim 1, wherein: Solving the equivalent thermal resistance and equivalent heat capacity of the first-order transient equivalent thermal circuit model based on historical temperature data includes: Substituting the first historical cable core temperature and the first historical cable surface temperature at the first acquisition moment into the first-order transient equivalent heat circuit model to obtain a first transient equivalent heat circuit equation; Substituting the second historical cable core temperature and the second historical cable surface temperature at the second acquisition moment into the first-order transient equivalent heat circuit model to obtain a second transient equivalent heat circuit equation; The first transient equivalent heat circuit equation and the second transient equivalent heat circuit equation are combined to solve the equivalent thermal resistance and equivalent heat capacity of the first-order transient equivalent heat circuit model.

3. The method for calculating the core temperature of a high-voltage cable according to claim 2, wherein: The first transient equivalent heat circuit equation and the second transient equivalent heat circuit equation are combined to solve the equivalent thermal resistance and equivalent heat capacity of the first-order transient equivalent heat circuit model, including: The transient temperature equation of the cable core is described by the fitting method, and the function of the transient temperature of the cable core with respect to time is determined; Differentiating the transient temperature of the cable core as a function of time to obtain a differential expression of the transient temperature of the cable core with respect to time; Substitute the differential expression of the transient temperature of the cable core with respect to time into the first transient equivalent heat circuit equation and the second transient equivalent heat circuit equation to solve the equivalent thermal resistance and equivalent heat capacity of the first-order transient equivalent heat circuit model.

4. The method for calculating the core temperature of a high-voltage cable according to claim 3, wherein: The transient temperature of the cable core as a function of time is: The differential expression of the transient temperature of the cable core with respect to time is: in, 、 、 is the fitting coefficient, For time.

5. A device for calculating the core temperature of a high-voltage cable, characterized in that: A method for calculating the core temperature of a high-voltage cable according to any one of claims 1 to 4, comprising: A thermal circuit model building module, configured to build a transient thermal circuit model of the high-voltage cable based on the structural composition of the high-voltage cable; A model equivalent module, used to convert the transient thermal circuit model of the high-voltage cable into a first-order transient equivalent thermal circuit model; A parameter solving module, configured to solve the equivalent thermal resistance and equivalent heat capacity of the first-order transient equivalent thermal circuit model based on historical temperature data; Real-time temperature acquisition module, used to obtain the real-time collected cable surface temperature; A cable core temperature calculation module is used to calculate the cable core temperature of the high-voltage cable based on the cable surface temperature, the equivalent thermal resistance and the equivalent heat capacity.

6. An electronic device, characterized in that: include: one or more processors; a storage device for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the method for calculating the core temperature of a high-voltage cable according to any one of claims 1 to 4.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method for calculating the core temperature of a high-voltage cable according to any one of claims 1 to 4 is implemented.

Citation Information

Patent Citations

  • Cable conductor temperature prediction system, method, apparatus and readable storage medium

    CN110319953A

  • Method and system for testing output power factor of charging module of direct current system

    CN116338299A