A method, device, electronic device and storage medium for optimizing the current carrying capacity of a multi-fiber built-in DC submarine cable

Abstract

The present invention discloses a method, device, electronic device, and storage medium for optimizing the current carrying capacity of a multi-fiber internal DC submarine cable. The method comprises: obtaining a first temperature of an optical fiber unit disposed on the outer surface of an insulating shielding layer, a second temperature of an optical fiber unit disposed within a polypropylene inner cushion layer, and the DC resistance of the conductor; when the first temperature or the second temperature exceeds a respective preset temperature threshold, obtaining the thermal resistance of the conductor, the thermal resistance of each material layer, and the third temperature of the optical fiber unit disposed at the center of the conductor; calculating and generating an adjusted current carrying capacity based on the thermal resistance of the conductor, the thermal resistance of each material layer, the first temperature, the second temperature, the third temperature, and the DC resistance of the conductor; and optimizing the current carrying capacity of the multi-fiber internal DC submarine cable based on the adjusted current carrying capacity. The implementation of the present invention can improve the accuracy of DC submarine cable current carrying capacity optimization.

Description

Technical Field

[0001] The present invention relates to the field of distributed optical fiber sensing technology, and in particular to a method, device, electronic equipment and storage medium for optimizing the current carrying capacity of a multi-optical built-in DC submarine cable. Background Art

[0002] High-voltage direct current (HVDC) submarine cables play a crucial role in connecting offshore wind farms to the onshore power grid. Optimizing their current carrying capacity is directly related to the efficiency and stability of the power system. The current carrying capacity of submarine cables must be dynamically adjusted based on factors such as ambient temperature, ocean currents, and waves to ensure efficient and safe operation. Optimizing current carrying capacity improves the grid's transmission capacity, reduces system energy loss, extends the service life of submarine cables, and reduces damage and failure due to overload or excessive temperatures. Therefore, accurately assessing and dynamically adjusting the current carrying capacity of submarine cables is crucial to ensuring the efficient operation of offshore wind farms and the stability of the power grid.

[0003] Currently, the main challenge in optimizing the current-carrying capacity of DC submarine cables lies in the inability of existing evaluation methods to fully reflect the relationship between the cable's variable temperature field and current-carrying capacity in complex marine environments. While existing technologies such as analytical methods, simulations, experimental testing, and distributed optical fiber sensing (DOFS) each have their own advantages, they still have limitations. The root cause of these issues lies in the lack of a comprehensive evaluation method that can accurately capture the relationship between internal cable temperature variations and current-carrying capacity, making it difficult to meet the dynamic optimization requirements of actual operations. Summary of the Invention

[0004] Embodiments of the present invention provide a method, device, electronic device, and storage medium for optimizing the current carrying capacity of a multi-fiber internal DC submarine cable. By implementing the present invention, the relationship between internal cable temperature changes and current carrying capacity can be revealed, thereby resolving the existing issues of being unable to accurately capture the relationship between cable temperature changes and current carrying capacity and lacking dynamic optimization methods, thereby improving the accuracy of DC submarine cable current carrying capacity optimization.

[0005] An embodiment of the present invention provides a method for optimizing the current carrying capacity of a multi-fiber internal DC submarine cable. The multi-fiber internal DC submarine cable includes a conductor and several material layers, the material layers including an insulating shielding layer and a polypropylene inner bedding layer. Optical fiber units are provided at the center of the conductor, on the outer surface of the insulating shielding layer, and within the polypropylene inner bedding layer.

[0006] The method comprises:

[0007] Obtaining a first temperature of the optical fiber unit disposed on the outer surface of the insulating shielding layer, a second temperature of the optical fiber unit disposed in the polypropylene inner pad, and a DC resistance of the conductor;

[0008] When the first temperature or the second temperature exceeds the respective preset temperature threshold, obtaining the thermal resistance of the conductor, the thermal resistance of each material layer, and a third temperature of the optical fiber unit disposed at the center of the conductor;

[0009] Calculating and generating an adjusted current carrying capacity according to the thermal resistance of the conductor, the thermal resistance of each material layer, the first temperature, the second temperature, the third temperature, and the DC resistance of the conductor;

[0010] According to the adjusted current-carrying capacity, the current-carrying capacity of the multi-fiber internal DC submarine cable is optimized.

[0011] Furthermore, the material layers of the multi-fiber built-in DC submarine cable also include: a conductor shielding layer, an XLPE insulation layer, a water-blocking buffer layer, an alloy lead sheath, a polyethylene lead sheath, a water-blocking tape, a steel wire armor layer, and a polyethylene outer sheath; along the radial direction of the multi-fiber built-in DC submarine cable, from the inside to the outside, they are the conductor, the conductor shielding layer, the XLPE insulation layer, the insulation shielding layer, the water-blocking buffer layer, the alloy lead sheath, the polyethylene lead sheath, the water-blocking tape, the polypropylene inner pad, the steel wire armor layer, and the polyethylene outer sheath; the number of optical fiber units arranged in the center of the conductor is one; the number of optical fiber units arranged on the outer surface of the insulation shielding layer is four, and the four optical fiber units are evenly distributed at the four equal points of the circumference; the number of optical fiber units arranged in the polypropylene inner pad is four, and the four optical fiber units are evenly distributed at the four equal points of the circumference; wherein each optical fiber unit contains two single-mode optical fibers.

[0012] Furthermore, the material layers of the multi-fiber built-in DC submarine cable also include: a conductor shielding layer, an XLPE insulation layer, a water-blocking buffer layer, an alloy lead sheath, a polyethylene lead sheath, a water-blocking tape, a steel wire armor layer, and a polyethylene outer sheath; along the radial direction of the multi-fiber built-in DC submarine cable, from the inside to the outside, they are the conductor, the conductor shielding layer, the XLPE insulation layer, the insulation shielding layer, the water-blocking buffer layer, the alloy lead sheath, the polyethylene lead sheath, the water-blocking tape, the polypropylene inner pad, the steel wire armor layer, and the polyethylene outer sheath; the number of optical fiber units arranged in the center of the conductor is one; the number of optical fiber units arranged on the outer surface of the insulation shielding layer is four, and the four optical fiber units are evenly distributed at the four equal points of the circumference; the number of optical fiber units arranged in the polypropylene inner pad is four, and the four optical fiber units are evenly distributed at the four equal points of the circumference; wherein each optical fiber unit contains two single-mode optical fibers.

[0013] Furthermore, the first temperature of the optical fiber unit disposed on the outer surface of the insulating shielding layer and the second temperature of the optical fiber unit disposed in the polypropylene inner pad are obtained by the following method:

[0014] Obtaining a temperature value of each optical fiber unit disposed on the outer surface of the insulating shielding layer, and averaging all the temperature values ​​of the optical fiber units disposed on the outer surface of the insulating shielding layer to generate a first temperature of the optical fiber units disposed on the outer surface of the insulating shielding layer;

[0015] The temperature value of each optical fiber unit disposed in the polypropylene inner cushion layer is obtained, and all temperature values ​​of the optical fiber units disposed in the polypropylene inner cushion layer are averaged to generate a second temperature of the optical fiber units disposed in the polypropylene inner cushion layer.

[0016] Furthermore, the thermal resistance of the conductor and the thermal resistance of each material layer are obtained by the following method:

[0017] Obtain material parameters of multi-fiber internal DC submarine cables;

[0018] Extracting the outer radius of the conductor's structure layer, the inner radius of the conductor's structure layer, the thermal conductivity of the conductor, the outer radius of each material layer's structure layer, the inner radius of each material layer's structure layer, and the thermal conductivity of each material layer based on the material parameters;

[0019] The thermal resistance of the conductor is calculated based on the outer radius of the conductor's structural layer, the inner radius of the conductor's structural layer, and the thermal conductivity of the conductor;

[0020] The thermal resistance of each material layer is calculated based on the outer radius of the structure layer of each material layer, the inner radius of the structure layer of each material layer, and the thermal conductivity of each material layer.

[0021] Furthermore, after calculating and generating the thermal resistance of each material layer according to the outer radius of the structural layer of each material layer, the inner radius of the structural layer of each material layer, and the thermal conductivity of each material layer, the method further includes:

[0022] Obtaining a first configuration file for modeling a multi-fiber built-in DC submarine cable; wherein the first configuration file is set with a modeling method for modeling the multi-fiber built-in DC submarine cable according to the material parameters;

[0023] Calling preset finite element simulation software to enable the preset finite element simulation software to model the multi-fiber internal DC submarine cable according to the modeling method in the first configuration file to obtain a DC submarine cable finite element model; wherein the DC submarine cable finite element model includes a simulated DC submarine cable; and the simulated DC submarine cable is provided with a simulated conductor;

[0024] Obtaining a second configuration file for injecting current into the finite element model of the DC submarine cable; wherein the second configuration file is provided with a current injection mode for injecting current so that the steady-state temperature of the simulated conductor reaches a preset conductor shielding layer temperature threshold;

[0025] calling a preset finite element simulation software so that the preset finite element simulation software performs current injection on the simulated DC submarine cable according to the current injection method in the second configuration file;

[0026] Record the current value of the simulated DC submarine cable at this time as the first current value;

[0027] Obtaining a fourth temperature of an optical fiber unit disposed on an outer surface of the insulating shielding layer and a fifth temperature of an optical fiber unit disposed in a polypropylene inner cushion layer when the conductor temperature of the multi-optical built-in DC submarine cable reaches a temperature threshold of the conductor shielding layer;

[0028] Repeating the calibration operation until the difference between the first current value and the second current value is within a preset error threshold range, generating an updated thermal resistance of the conductor and an updated thermal resistance of each material layer;

[0029] The correction operation includes:

[0030] Calculating and generating a second current value according to the DC resistance of the conductor, the current thermal resistance of the conductor, the current thermal resistance of each material layer, the fourth temperature, and the fifth temperature;

[0031] Determine whether the difference between the first current value and the second current value is within a preset error threshold; if so, use the current thermal resistance of the conductor as the updated thermal resistance of the conductor; and use the current thermal resistance of each material layer as the updated thermal resistance of the corresponding material layer;

[0032] If not, the current thermal resistance of the conductor and the current thermal resistance of each material layer are adjusted according to the difference between the first current value and the second current value to generate updated current thermal resistance of the conductor and updated current thermal resistance of each material layer.

[0033] Furthermore, the calculating and generating the adjusted current carrying capacity according to the thermal resistance of the conductor, the thermal resistance of each material layer, the first temperature, the second temperature, the third temperature, and the DC resistance of the conductor includes:

[0034] The first current carrying capacity is calculated using the following formula:

[0035]

[0036] Among them, I new1 is the first current carrying capacity; T1 is the third temperature; T4 is the first temperature; R is the DC resistance of the conductor; R T1 is the thermal resistance of the conductor; R T2 is the thermal resistance of the conductor shield; R T3 is the thermal resistance of the XLPE insulation layer; R T4 is the thermal resistance of the insulating shield;

[0037] The second current carrying capacity is calculated using the following formula:

[0038]

[0039] Among them, I new2 is the second current carrying capacity; T9 is the second temperature; R T4 is the thermal resistance of the insulating shield; R T5 is the thermal resistance of the water-blocking buffer layer; R T6 is the thermal resistance of the alloy lead sheath; R T7 is the thermal resistance of the polyethylene lead sheath; R T8 is the thermal resistance of the water-blocking tape; R T9 is the thermal resistance of the polypropylene inner pad;

[0040] The smaller value of the first current carrying capacity and the second current carrying capacity is taken as the adjusted current carrying capacity.

[0041] Based on the above method embodiments, the present invention provides corresponding device embodiments.

[0042] An embodiment of the present invention provides a device for optimizing the current carrying capacity of a multi-fiber internal DC submarine cable, comprising:

[0043] A first data acquisition module, a second data acquisition module, a current carrying capacity calculation module and a current carrying capacity optimization module;

[0044] The first data acquisition module is used to acquire a first temperature of the optical fiber unit provided on the outer surface of the insulating shielding layer, a second temperature of the optical fiber unit provided in the polypropylene inner pad, and a DC resistance of the conductor;

[0045] The second data acquisition module is configured to acquire the thermal resistance of the conductor, the thermal resistance of each material layer, and a third temperature of the optical fiber unit disposed at the center of the conductor when the first temperature or the second temperature exceeds the respective preset temperature threshold;

[0046] The current carrying capacity calculation module is used to calculate and generate the adjusted current carrying capacity based on the thermal resistance of the conductor, the thermal resistance of each material layer, the first temperature, the second temperature, the third temperature, and the DC resistance of the conductor;

[0047] The current carrying capacity optimization module is used to optimize the current carrying capacity of the multi-fiber built-in DC submarine cable according to the adjusted current carrying capacity.

[0048] Furthermore, the current carrying capacity optimization device of the multi-fiber built-in DC submarine cable, the first data acquisition module includes: a first temperature acquisition unit and a second temperature acquisition unit;

[0049] The first temperature acquisition unit is used to acquire the temperature value of each optical fiber unit provided on the outer surface of the insulating shielding layer, and average all the temperature values ​​of the optical fiber units provided on the outer surface of the insulating shielding layer to generate a first temperature of the optical fiber units provided on the outer surface of the insulating shielding layer;

[0050] The second temperature acquisition unit is used to acquire the temperature value of each optical fiber unit set in the polypropylene inner pad, and average all the temperature values ​​of the optical fiber units set in the polypropylene inner pad to generate a second temperature of the optical fiber units set in the polypropylene inner pad.

[0051] Based on the above method embodiment, the present invention provides a corresponding electronic device embodiment.

[0052] An embodiment of the present invention provides an electronic device, including a memory, a processor, and a computer program stored in the memory and runnable on the processor. When the processor executes the computer program, it can implement the method for optimizing the current carrying capacity of a multi-fiber internal DC submarine cable as described in any one of the above-mentioned method embodiments.

[0053] Based on the above method embodiment, the present invention provides a corresponding storage medium embodiment.

[0054] An embodiment of the present invention provides a storage medium having a computer program stored thereon. When the computer program is executed by a processor, the method for optimizing the current carrying capacity of a multi-fiber internal DC submarine cable as described in any one of the above method embodiments can be implemented.

[0055] Compared with the prior art, the present invention has the following beneficial effects:

[0056] Embodiments of the present invention provide a method, device, electronic device, and storage medium for optimizing the current-carrying capacity of a multi-fiber, internally DC submarine cable. This method acquires temperature data from optical fiber units at different locations and the DC resistance of the conductors, combining this thermal resistance information to monitor the cable's operating status in real time. When the temperature exceeds a preset threshold, the method further acquires thermal resistance data from the conductors and material layers and calculates the adjusted current-carrying capacity. Ultimately, the cable's current-carrying capacity is optimized to ensure optimal operation.

[0057] By installing optical fiber units within the various material layers of a DC submarine cable, this new technology monitors temperature changes in real time, comprehensively reflecting the cable's temperature distribution in complex marine environments. Combining the temperature data detected by the optical fiber units with the thermal resistance information of each material layer, the current-carrying capacity is dynamically calculated, accurately revealing the relationship between internal cable temperature changes and current-carrying capacity. This addresses the existing issues of accurately capturing the relationship between cable temperature changes and current-carrying capacity and the lack of dynamic optimization methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 The present invention provides a flow chart of a method for optimizing the current carrying capacity of a multi-fiber internal DC submarine cable according to an embodiment of the present invention.

[0059] Figure 2 It is a structural schematic diagram of a multi-fiber internal DC submarine cable provided by one embodiment of the present invention.

[0060] Figure 3 The present invention provides a schematic structural diagram of a device for optimizing the current carrying capacity of a multi-fiber internal DC submarine cable according to an embodiment of the present invention.

[0061] Description of reference numerals:

[0062] 1. Optical fiber unit; 2. Conductor; 3. Conductor shielding layer; 4. XLPE insulation layer; 5. Insulation shielding layer; 6. Water-blocking buffer layer; 7. Alloy lead sheath; 8. Polyethylene lead sheath; 9. Water-blocking tape; 10. Polypropylene inner cushion layer; 11. Steel wire armor layer; 12. Polyethylene outer sheath. DETAILED DESCRIPTION

[0063] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0064] like Figure 1 As shown, an embodiment of the present invention provides a method for optimizing the current carrying capacity of a multi-fiber internal DC submarine cable. The multi-fiber internal DC submarine cable includes a conductor 2 and several material layers, the material layers including an insulating shielding layer 5 and a polypropylene inner pad 10. Optical fiber units 1 are provided at the center of the conductor 2, on the outer surface of the insulating shielding layer 5, and inside the polypropylene inner pad 10.

[0065] The method comprises at least the following steps:

[0066] Step S1 , obtaining a first temperature of the optical fiber unit 1 disposed on the outer surface of the insulating shielding layer 5 , a second temperature of the optical fiber unit 1 disposed in the polypropylene inner pad 10 , and a DC resistance of the conductor 2 .

[0067] like Figure 2As shown, an embodiment of the present invention provides a structural schematic diagram of a multi-fiber built-in DC submarine cable. The material layers of the multi-fiber built-in DC submarine cable, in addition to the insulating shielding layer 5 and the polypropylene inner pad 10, also include: a conductor shielding layer 3, an XLPE insulating layer 4, a water-blocking buffer layer 6, an alloy lead sheath 7, a polyethylene lead sheath 8, a water-blocking tape 9, a steel wire armor layer 11 and a polyethylene outer sheath 12; along the radial direction of the multi-fiber built-in DC submarine cable, from the inside to the outside, are the conductor 2, the conductor shielding layer 3, the XLPE insulating layer 4, the insulating shielding layer 5, the water-blocking buffer layer 6, the alloy lead sheath 7, the polyethylene lead sheath 8, the water-blocking tape 9, A polypropylene inner cushion layer 10, a steel wire armor layer 11 and a polyethylene outer sheath 12; one optical fiber unit 1 is arranged at the center of the conductor 2; four optical fiber units 1 are arranged on the outer surface of the insulating shielding layer 5, and the four optical fiber units 1 are evenly distributed on the quarter-division points of the circumference; four optical fiber units 1 are arranged in the polypropylene inner cushion layer 10, and the four optical fiber units 1 are evenly distributed on the quarter-division points of the circumference; wherein each optical fiber unit 1 contains two single-mode optical fibers; the diameter of the single-mode optical fiber is 0.6 mm, and the optical fiber attenuation coefficient in the 1550 nm band is less than 0.2 dB / km.

[0068] In a preferred embodiment, the first temperature of the optical fiber unit 1 disposed on the outer surface of the insulating shielding layer 5 and the second temperature of the optical fiber unit 1 disposed in the polypropylene inner pad 10 are obtained by:

[0069] Obtaining a temperature value of each optical fiber unit 1 disposed on the outer surface of the insulating shielding layer 5, and averaging all the temperature values ​​of the optical fiber units 1 disposed on the outer surface of the insulating shielding layer 5 to generate a first temperature of the optical fiber units 1 disposed on the outer surface of the insulating shielding layer 5;

[0070] The temperature value of each optical fiber unit 1 disposed in the polypropylene inner pad 10 is obtained, and all temperature values ​​of the optical fiber unit 1 disposed in the polypropylene inner pad 10 are averaged to generate a second temperature of the optical fiber unit 1 disposed in the polypropylene inner pad 10.

[0071] What needs to be explained here is that the BOTDR distributed optical fiber sensing terminal is used to receive the temperature measurement signal of the optical fiber built into the cable, and the operating band is 1550nm.

[0072] Step S2: When the first temperature or the second temperature exceeds a respective preset temperature threshold, obtaining the thermal resistance of the conductor 2, the thermal resistance of each material layer, and a third temperature of the optical fiber unit 1 disposed at the center of the conductor 2. The temperature threshold of the first temperature may be 70° C., and the temperature threshold of the second temperature may be 70° C. or 80° C.

[0073] In a preferred embodiment, the thermal resistance of the conductor 2 and the thermal resistance of each material layer are obtained by:

[0074] Obtain material parameters of multi-fiber internal DC submarine cables;

[0075] Extracting the outer radius of the structure layer of conductor 2, the inner radius of the structure layer of conductor 2, the thermal conductivity of conductor 2, the outer radius of the structure layer of each material layer, the inner radius of the structure layer of each material layer, and the thermal conductivity of each material layer based on the material parameters;

[0076] Calculate and generate the thermal resistance of conductor 2 according to the outer radius of the structural layer of conductor 2, the inner radius of the structural layer of conductor 2, and the thermal conductivity of conductor 2;

[0077] The thermal resistance of each material layer is calculated based on the outer radius of the structure layer of each material layer, the inner radius of the structure layer of each material layer, and the thermal conductivity of each material layer.

[0078] Specifically, the thermal resistance of each material layer can also be obtained by the following formula:

[0079]

[0080] Among them, R T is the thermal resistance of the material layer; r out is the outer radius of the structural layer; r in is the inner radius of the structural layer; k is the thermal conductivity of the corresponding material layer.

[0081] Similarly, the thermal resistance of conductor 2 can also be solved according to the above formula.

[0082] In an optional embodiment, after calculating and generating the thermal resistance of each material layer according to the outer radius of the structural layer of each material layer, the inner radius of the structural layer of each material layer, and the thermal conductivity of each material layer, the method further includes:

[0083] Obtaining a first configuration file for modeling a multi-fiber built-in DC submarine cable; wherein the first configuration file is set with a modeling method for modeling the multi-fiber built-in DC submarine cable according to the material parameters;

[0084] Calling the preset finite element simulation software so that the preset finite element simulation software models the multi-fiber built-in DC submarine cable according to the modeling method in the first configuration file to obtain a DC submarine cable finite element model; wherein the DC submarine cable finite element model includes a simulated DC submarine cable; a simulated conductor is provided in the simulated DC submarine cable; the finite element simulation software is COMSOL Multiphysics.

[0085] Obtain a second configuration file for injecting current into the finite element model of a DC submarine cable; wherein, the second configuration file is provided with a current injection method for injecting current so that the steady-state temperature of the simulated conductor reaches a preset conductor shielding layer temperature threshold; wherein, the preset conductor shielding layer temperature threshold can be 70°C.

[0086] calling a preset finite element simulation software so that the preset finite element simulation software performs current injection on the simulated DC submarine cable according to the current injection method in the second configuration file;

[0087] Record the current value of the simulated DC submarine cable at this time as the first current value;

[0088] Obtaining a fourth temperature of the optical fiber unit 1 disposed on the outer surface of the insulating shielding layer 5 and a fifth temperature of the optical fiber unit 1 disposed in the polypropylene inner pad 10 of the multi-fiber built-in DC submarine cable when the temperature of the conductor 2 reaches the temperature threshold of the conductor shielding layer;

[0089] Repeating the calibration operation until the difference between the first current value and the second current value is within a preset error threshold range, generating an updated thermal resistance of the conductor 2 and an updated thermal resistance of each material layer;

[0090] The correction operation includes:

[0091] The second current value is calculated based on the DC resistance of conductor 2, the current thermal resistance of conductor 2, the current thermal resistance of each material layer, the fourth temperature, and the fifth temperature. The specific calculation method can refer to formula (2) and formula (3).

[0092] Determine whether the difference between the first current value and the second current value is within a preset error threshold range; if so, use the current thermal resistance of the conductor 2 as the updated thermal resistance of the conductor 2; use the current thermal resistance of each material layer as the updated thermal resistance of the corresponding material layer; wherein the error threshold range can be set to 0.5% to 2% of the rated current, and the specific value is determined according to the accuracy of the measuring equipment and the operating conditions.

[0093] If not, the current thermal resistance of the conductor 2 and the current thermal resistance of each material layer are adjusted according to the difference between the first current value and the second current value to generate updated current thermal resistance of the conductor 2 and updated current thermal resistance of each material layer.

[0094] Specifically, if the difference between the first current value and the second current value exceeds the preset error threshold range, the thermal resistance of conductor 2 and the thermal resistance of each material layer can be proportionally adjusted according to the difference. For example, if the first current value is 2000A and the second current value is 1900A, the difference is 100A. Assuming that the preset error threshold range at this time is ±50A, it means that the current total thermal resistance is too large. At this time, according to the linear relationship between thermal resistance and difference, the thermal resistance of conductor 2 and the thermal resistance of each material layer can be reduced respectively, such as reducing the thermal resistance of conductor 2 from 0.001Ω·m 2 / K is adjusted to 0.00095Ω·m 2 / K, thermal resistance of insulation layer from 0.002Ω·m 2 / K is adjusted to 0.0019Ω·m 2 / K, thermal resistance of polypropylene inner pad is from 0.003Ω·m 2 / K is adjusted to 0.00285Ω·m 2 / K, to gradually approach the target state within the error threshold range.

[0095] Step S3: Calculate and generate an adjusted current carrying capacity according to the thermal resistance of the conductor 2 , the thermal resistance of each material layer, the first temperature, the second temperature, the third temperature, and the DC resistance of the conductor 2 .

[0096] In a preferred embodiment, the calculating and generating the adjusted current carrying capacity according to the thermal resistance of the conductor 2, the thermal resistance of each material layer, the first temperature, the second temperature, the third temperature, and the DC resistance of the conductor 2 includes:

[0097] The first current carrying capacity is calculated using the following formula:

[0098]

[0099] Among them, I new1 is the first current carrying capacity; T1 is the third temperature; T4 is the first temperature; R is the DC resistance of conductor 2; R T1 is the thermal resistance of conductor 2; R T2 is the thermal resistance of the conductor shielding layer 3; R T3 is the thermal resistance of the XLPE insulation layer 4; R T4 is the thermal resistance of the insulating shielding layer 5;

[0100] The second current carrying capacity is calculated using the following formula:

[0101]

[0102] Among them, I new2 is the second current carrying capacity; T9 is the second temperature; R T4 is the thermal resistance of the insulating shielding layer 5; R T5 is the thermal resistance of the water-blocking buffer layer 6; R T6is the thermal resistance of the alloy lead sheath 7; R T7 is the thermal resistance of the polyethylene lead sheath 8; R T8 is the thermal resistance of the water-blocking tape 9; R T9 is the thermal resistance of the polypropylene inner pad 10;

[0103] The smaller value of the first current carrying capacity and the second current carrying capacity is taken as the adjusted current carrying capacity.

[0104] It should be noted here that the following is the derivation process of the above-mentioned current carrying capacity calculation formula:

[0105] According to the thermal balance equation in the IEC60287 standard, we know that:

[0106] P loss =I 2 ·R (4)

[0107] Where I is the current; R is the DC resistance of the conductor; P loss is heat loss;

[0108] Furthermore, the balance between heat loss and heat dissipated to the outside is considered under steady-state conditions:

[0109] P loss =Q out (5)

[0110] Among them, Q out is the heat dissipated by the conductor, which can be calculated by the material thermal resistance and temperature difference:

[0111]

[0112] Among them, T in is the temperature of the material layer closer to the conductor; T out is the temperature of the material layer farther away from the conductor; R T is the material thermal resistance; the calculation formula of the material thermal resistance is shown in formula (1).

[0113] Substituting equations (4) and (6) into equation (5) and simplifying them, we can obtain the calculation relationship between the current carrying capacity and the temperature of each layer of the built-in optical fiber:

[0114]

[0115] Substituting formula (7) into the actual situation, we can obtain formula (2) and formula (3).

[0116] Step S4: Optimizing the current carrying capacity of the multi-fiber internal DC submarine cable according to the adjusted current carrying capacity.

[0117] Based on the above method embodiments, the present invention provides corresponding device embodiments.

[0118] like Figure 3 As shown, an embodiment of the present invention provides a current carrying capacity optimization device for a multi-fiber built-in DC submarine cable, comprising: a first data acquisition module, a second data acquisition module, a current carrying capacity calculation module, and a current carrying capacity optimization module;

[0119] The first data acquisition module is used to obtain a first temperature of the optical fiber unit 1 provided on the outer surface of the insulating shielding layer 5, a second temperature of the optical fiber unit 1 provided in the polypropylene inner pad 10, and a DC resistance of the conductor 2;

[0120] The second data acquisition module is configured to acquire the thermal resistance of the conductor 2, the thermal resistance of each material layer, and the third temperature of the optical fiber unit 1 disposed at the center of the conductor 2 when the first temperature or the second temperature exceeds the respective preset temperature thresholds;

[0121] The current carrying capacity calculation module is used to calculate and generate the adjusted current carrying capacity based on the thermal resistance of the conductor 2, the thermal resistance of each material layer, the first temperature, the second temperature, the third temperature and the DC resistance of the conductor 2;

[0122] The current carrying capacity optimization module is used to optimize the current carrying capacity of the multi-fiber built-in DC submarine cable according to the adjusted current carrying capacity.

[0123] In a preferred embodiment, the current carrying capacity optimization device of the multi-fiber built-in DC submarine cable, the first data acquisition module includes: a first temperature acquisition unit and a second temperature acquisition unit;

[0124] The first temperature acquisition unit is used to acquire the temperature value of each optical fiber unit 1 provided on the outer surface of the insulating shielding layer 5, and average all the temperature values ​​of the optical fiber units 1 provided on the outer surface of the insulating shielding layer 5 to generate a first temperature of the optical fiber unit 1 provided on the outer surface of the insulating shielding layer 5;

[0125] The second temperature acquisition unit is used to obtain the temperature value of each optical fiber unit 1 set in the polypropylene inner pad 10, and average all the temperature values ​​of the optical fiber unit 1 set in the polypropylene inner pad 10 to generate a second temperature of the optical fiber unit 1 set in the polypropylene inner pad 10.

[0126] It should be noted that the embodiment of the device described above corresponds to the above-mentioned embodiment of the present invention, and it can implement the method for optimizing the current carrying capacity of the multi-fiber built-in DC submarine cable described in any one of the above-mentioned embodiments of the present invention. In addition, the embodiment of the above-mentioned device is merely schematic, wherein the modules described as separate components may or may not be physically separated, and the components displayed as modules 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 can be selected according to actual needs to achieve the purpose of the scheme of this embodiment. In addition, in the drawings of the embodiment of the device provided by the present invention, the connection relationship between the modules indicates that there is a communication connection between them, which can be specifically implemented as one or more communication buses or signal lines. A person of ordinary skill in the art can understand and implement it without paying any creative work.

[0127] Based on the above method embodiment of the present invention, a corresponding electronic device embodiment is provided.

[0128] An embodiment of the present invention provides an electronic device, comprising a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, the method for optimizing the current carrying capacity of a multi-fiber internal DC submarine cable described in any one of the present invention is implemented, or when the processor executes the computer program, the functions of each module in the above-mentioned device embodiments are implemented.

[0129] Exemplarily, the computer program may be divided into one or more modules, which are stored in the memory and executed by the processor to implement the present invention. The one or more modules may be a series of computer program instruction segments capable of performing specific functions, and the instruction segments are used to describe the execution process of the computer program in the terminal device.

[0130] The terminal device may be a computing device such as a desktop computer, a notebook computer, a PDA, a cloud server, etc. The terminal device may include, but is not limited to, a processor and a memory.

[0131] The processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc. The processor is the control center of the terminal device, connecting various parts of the entire terminal device using various interfaces and lines.

[0132] The memory can be used to store the computer programs and / or modules, and the processor implements various functions of the terminal device by running or executing the computer programs and / or modules stored in the memory, and calling the data stored in the memory. The memory can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, at least one application required for a function, etc.; the data storage area can store data created based on the use of the mobile phone, etc. In addition, the memory can include a high-speed random access memory, and can also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), at least one disk storage device, a flash memory device, or other volatile solid-state storage device.

[0133] Based on the above method embodiment, the present invention provides a corresponding storage medium embodiment;

[0134] Another embodiment of the present invention provides a storage medium, which includes a stored computer program, wherein when the computer program is running, the device where the storage medium is located is controlled to execute any of the above-mentioned methods for optimizing the current carrying capacity of the multi-fiber internal DC submarine cable of the present invention.

[0135] The above-mentioned storage medium is a computer-readable storage medium, and the computer program includes computer program code, which may be in source code form, object code form, executable file, or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal, and software distribution medium, etc. It should be noted that the content contained in the computer-readable medium may be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electric carrier signals and telecommunication signals.

[0136] In the description of this specification, the reference terms "one embodiment," "some embodiments," "example," "specific example," or "some examples" mean that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. Moreover, the specific features, structures, materials, or characteristics described may be combined in any appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and integrate different embodiments or examples described in this specification, as well as features of different embodiments or examples, unless they are mutually inconsistent.

[0137] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A method for optimizing the current carrying capacity of a multi-fiber internal DC submarine cable, characterized in that: The multi-fiber internal DC submarine cable comprises a conductor and several material layers, wherein the material layers include an insulating shielding layer and a polypropylene inner padding layer, and optical fiber units are arranged at the center of the conductor, on the outer surface of the insulating shielding layer, and in the polypropylene inner padding layer; The method comprises: Obtaining a first temperature of the optical fiber unit disposed on the outer surface of the insulating shielding layer, a second temperature of the optical fiber unit disposed in the polypropylene inner pad, and a DC resistance of the conductor; When the first temperature or the second temperature exceeds the respective preset temperature threshold, obtaining the thermal resistance of the conductor, the thermal resistance of each material layer, and a third temperature of the optical fiber unit disposed at the center of the conductor; Calculating and generating an adjusted current carrying capacity according to the thermal resistance of the conductor, the thermal resistance of each material layer, the first temperature, the second temperature, the third temperature, and the DC resistance of the conductor; Optimizing the current carrying capacity of the multi-fiber internal DC submarine cable according to the adjusted current carrying capacity; The step of calculating and generating the adjusted current carrying capacity based on the thermal resistance of the conductor, the thermal resistance of each material layer, the first temperature, the second temperature, the third temperature, and the DC resistance of the conductor includes: The first current carrying capacity is calculated using the following formula: in, is the first current carrying capacity; is the third temperature; is the first temperature; is the DC resistance of the conductor; is the thermal resistance of the conductor; is the thermal resistance of the conductor shield; is the thermal resistance of the XLPE insulation layer; is the thermal resistance of the insulating shield; The second current carrying capacity is calculated using the following formula: in, is the second current carrying capacity; is the second temperature; is the thermal resistance of the insulating shield; is the thermal resistance of the water-blocking buffer layer; is the thermal resistance of the alloy lead sheath; is the thermal resistance of the polyethylene lead sheath; is the thermal resistance of the water-blocking tape; is the thermal resistance of the polypropylene inner pad; The smaller value of the first current carrying capacity and the second current carrying capacity is taken as the adjusted current carrying capacity.

2. The method for optimizing the current carrying capacity of a multi-fiber internal DC submarine cable according to claim 1, characterized in that: The material layers of the multi-fiber built-in DC submarine cable also include: a conductor shielding layer, an XLPE insulation layer, a water-blocking buffer layer, an alloy lead sheath, a polyethylene lead sheath, a water-blocking tape, a steel wire armor layer, and a polyethylene outer sheath; along the radial direction of the multi-fiber built-in DC submarine cable, from the inside to the outside, they are the conductor, the conductor shielding layer, the XLPE insulation layer, the insulation shielding layer, the water-blocking buffer layer, the alloy lead sheath, the polyethylene lead sheath, the water-blocking tape, the polypropylene inner pad, the steel wire armor layer, and the polyethylene outer sheath; the number of optical fiber units arranged at the center of the conductor is one; the number of optical fiber units arranged on the outer surface of the insulation shielding layer is four, and the four optical fiber units are evenly distributed at the four equal points of the circumference; the number of optical fiber units arranged in the polypropylene inner pad is four, and the four optical fiber units are evenly distributed at the four equal points of the circumference; wherein each optical fiber unit contains two single-mode optical fibers.

3. The method for optimizing the current carrying capacity of a multi-fiber internal DC submarine cable according to claim 2, wherein: The first temperature of the optical fiber unit disposed on the outer surface of the insulating shielding layer and the second temperature of the optical fiber unit disposed in the polypropylene inner cushion layer are obtained by: Obtaining a temperature value of each optical fiber unit disposed on the outer surface of the insulating shielding layer, and averaging all the temperature values ​​of the optical fiber units disposed on the outer surface of the insulating shielding layer to generate a first temperature of the optical fiber units disposed on the outer surface of the insulating shielding layer; The temperature value of each optical fiber unit disposed in the polypropylene inner cushion layer is obtained, and all temperature values ​​of the optical fiber units disposed in the polypropylene inner cushion layer are averaged to generate a second temperature of the optical fiber units disposed in the polypropylene inner cushion layer.

4. The method for optimizing the current carrying capacity of a multi-fiber internal DC submarine cable according to claim 3, wherein: The thermal resistance of the conductor and the thermal resistance of each material layer are obtained by: Obtain material parameters of multi-fiber internal DC submarine cables; Extracting the outer radius of the conductor's structure layer, the inner radius of the conductor's structure layer, the thermal conductivity of the conductor, the outer radius of each material layer's structure layer, the inner radius of each material layer's structure layer, and the thermal conductivity of each material layer based on the material parameters; The thermal resistance of the conductor is calculated based on the outer radius of the conductor's structural layer, the inner radius of the conductor's structural layer, and the thermal conductivity of the conductor; The thermal resistance of each material layer is calculated based on the outer radius of the structure layer of each material layer, the inner radius of the structure layer of each material layer, and the thermal conductivity of each material layer.

5. The method for optimizing the current carrying capacity of a multi-fiber internal DC submarine cable according to claim 4, characterized in that: After calculating and generating the thermal resistance of each material layer according to the outer radius of the structural layer of each material layer, the inner radius of the structural layer of each material layer, and the thermal conductivity of each material layer, the method further includes: Obtaining a first configuration file for modeling a multi-fiber built-in DC submarine cable; wherein the first configuration file is set with a modeling method for modeling the multi-fiber built-in DC submarine cable according to the material parameters; Calling preset finite element simulation software to enable the preset finite element simulation software to model the multi-fiber internal DC submarine cable according to the modeling method in the first configuration file to obtain a DC submarine cable finite element model; wherein the DC submarine cable finite element model includes a simulated DC submarine cable; and the simulated DC submarine cable is provided with a simulated conductor; Obtaining a second configuration file for injecting current into the finite element model of the DC submarine cable; wherein the second configuration file is provided with a current injection mode for injecting current so that the steady-state temperature of the simulated conductor reaches a preset conductor shielding layer temperature threshold; calling a preset finite element simulation software so that the preset finite element simulation software performs current injection on the simulated DC submarine cable according to the current injection method in the second configuration file; Record the current value of the simulated DC submarine cable at this time as the first current value; Obtaining a fourth temperature of an optical fiber unit disposed on an outer surface of the insulating shielding layer and a fifth temperature of an optical fiber unit disposed in a polypropylene inner cushion layer when the conductor temperature of the multi-optical built-in DC submarine cable reaches a temperature threshold of the conductor shielding layer; Repeating the calibration operation until the difference between the first current value and the second current value is within a preset error threshold range, generating an updated thermal resistance of the conductor and an updated thermal resistance of each material layer; The correction operation includes: Calculating and generating a second current value according to the DC resistance of the conductor, the current thermal resistance of the conductor, the current thermal resistance of each material layer, the fourth temperature, and the fifth temperature; Determine whether the difference between the first current value and the second current value is within a preset error threshold; if so, use the current thermal resistance of the conductor as the updated thermal resistance of the conductor; and use the current thermal resistance of each material layer as the updated thermal resistance of the corresponding material layer; If not, the current thermal resistance of the conductor and the current thermal resistance of each material layer are adjusted according to the difference between the first current value and the second current value to generate updated current thermal resistance of the conductor and updated current thermal resistance of each material layer.

6. A device for optimizing the current carrying capacity of a multi-fiber built-in DC submarine cable, characterized in that: include: A first data acquisition module, a second data acquisition module, a current carrying capacity calculation module and a current carrying capacity optimization module; The first data acquisition module is used to acquire a first temperature of the optical fiber unit provided on the outer surface of the insulating shielding layer, a second temperature of the optical fiber unit provided in the polypropylene inner pad, and a DC resistance of the conductor; The second data acquisition module is configured to acquire the thermal resistance of the conductor, the thermal resistance of each material layer, and a third temperature of the optical fiber unit disposed at the center of the conductor when the first temperature or the second temperature exceeds the respective preset temperature threshold; The current carrying capacity calculation module is used to calculate and generate the adjusted current carrying capacity based on the thermal resistance of the conductor, the thermal resistance of each material layer, the first temperature, the second temperature, the third temperature, and the DC resistance of the conductor; The current carrying capacity optimization module is used to optimize the current carrying capacity of the multi-fiber internal DC submarine cable according to the adjusted current carrying capacity; The step of calculating and generating the adjusted current carrying capacity based on the thermal resistance of the conductor, the thermal resistance of each material layer, the first temperature, the second temperature, the third temperature, and the DC resistance of the conductor includes: The first current carrying capacity is calculated using the following formula: in, is the first current carrying capacity; is the third temperature; is the first temperature; is the DC resistance of the conductor; is the thermal resistance of the conductor; is the thermal resistance of the conductor shield; is the thermal resistance of the XLPE insulation layer; is the thermal resistance of the insulating shield; The second current carrying capacity is calculated using the following formula: in, is the second current carrying capacity; is the second temperature; is the thermal resistance of the insulating shield; is the thermal resistance of the water-blocking buffer layer; is the thermal resistance of the alloy lead sheath; is the thermal resistance of the polyethylene lead sheath; is the thermal resistance of the water-blocking tape; is the thermal resistance of the polypropylene inner pad; The smaller value of the first current carrying capacity and the second current carrying capacity is taken as the adjusted current carrying capacity.

7. The current carrying capacity optimization device for a multi-fiber internal DC submarine cable according to claim 6, characterized in that: The first data acquisition module includes: a first temperature acquisition unit and a second temperature acquisition unit; The first temperature acquisition unit is used to acquire the temperature value of each optical fiber unit provided on the outer surface of the insulating shielding layer, and average all the temperature values ​​of the optical fiber units provided on the outer surface of the insulating shielding layer to generate a first temperature of the optical fiber units provided on the outer surface of the insulating shielding layer; The second temperature acquisition unit is used to acquire the temperature value of each optical fiber unit set in the polypropylene inner pad, and average all the temperature values ​​of the optical fiber units set in the polypropylene inner pad to generate a second temperature of the optical fiber units set in the polypropylene inner pad.

8. 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 computer program, it can implement the current carrying capacity optimization method of the multi-fiber internal DC submarine cable as described in any one of claims 1 to 5.

9. A storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, it can implement the method for optimizing the current carrying capacity of a multi-fiber internal DC submarine cable as described in any one of claims 1 to 5.

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