Current-carrying capacity optimization method and device for multi-fiber built-in DC submarine cable, electronic equipment and storage medium

Abstract

The invention discloses a current-carrying capacity optimization method and device for a multi-optical-fiber built-in direct-current submarine cable, electronic equipment and a storage medium. The method comprises the steps that the first temperature of an optical fiber unit arranged on the outer surface of an insulation shielding layer, the second temperature of an optical fiber unit arranged in a polypropylene inner cushion layer and the direct-current resistance of a conductor are acquired; acquiring the thermal resistance of the conductor, the thermal resistance of each material layer and the third temperature of an optical fiber unit arranged in the center of the conductor under the condition that the first temperature or the second temperature exceeds the respective preset temperature threshold value; calculating and generating 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 direct-current resistance of the conductor; and optimizing the current-carrying capacity of the multi-fiber built-in DC submarine cable according to the adjusted current-carrying capacity. By implementing the method, the accuracy of optimizing the current-carrying capacity of the direct-current submarine cable can be improved.

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 submarine cables play a vital role between offshore wind farms and land power grids, and the optimization of their current carrying capacity is directly related to the efficiency and stability of the power system. The current carrying capacity of submarine cables needs to be dynamically adjusted according to factors such as ambient temperature, ocean currents, and waves to ensure that the cables operate in an efficient and safe working state. By optimizing the current carrying capacity, the transmission capacity of the power grid can be improved, the energy loss of the system can be reduced, the service life of the submarine cables can be extended, and cable damage and failure caused by overload or excessive temperature can be reduced. Therefore, accurately evaluating 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] At present, the main problem in optimizing the current carrying capacity of DC submarine cables is that the existing evaluation methods cannot fully reflect the relationship between the variable temperature field and the current carrying capacity of the submarine cable in a complex marine environment. Although existing technologies such as analytical methods, simulation methods, experimental testing methods and distributed optical fiber sensing technology (DOFS) have their own advantages, they still have certain limitations. The root cause of these problems is the lack of a holographic evaluation method that can accurately capture the relationship between the temperature change inside the submarine cable and the current carrying capacity, which makes it difficult to meet the dynamic optimization needs in actual operation. Summary of the invention

[0004] The 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, it is possible to reveal the relationship between the temperature change inside the submarine cable and the current carrying capacity, thereby solving the problem that the prior art cannot accurately capture the correlation between the temperature change of the submarine cable and the current carrying capacity and lacks dynamic optimization means, and improves the accuracy of the 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, wherein the multi-fiber internal DC submarine cable comprises a conductor and a plurality of material layers, wherein the material layers include an insulating shielding layer and a polypropylene inner cushion 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 cushion layer;

[0006] The method comprises:

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

[0009] Calculate and generate 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 cushion layer, 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 cushion layer 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 cushion layer, 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 cushion layer 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] Further, 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 the following method:

[0014] Obtaining the 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] According to the material parameters, extract 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 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;

[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 and generated 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.

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

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

[0023] Calling a preset finite element simulation software, so that the preset finite element simulation software models the multi-fiber internal DC submarine cable according to the modeling method in the first configuration file, and obtains a DC submarine cable finite element model; wherein the DC submarine cable finite element model includes a simulated DC submarine cable; and a simulated conductor is arranged in the simulated DC submarine cable;

[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 the 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 comprises:

[0030] Calculate and generate 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 range; if so, use the current thermal resistance of the conductor as the updated thermal resistance of the conductor; 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] Further, 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 by 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 shielding layer; 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 by 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 cushion;

[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 embodiment, the present invention provides a corresponding device embodiment.

[0042] An embodiment of the present invention provides a current carrying capacity optimization device for 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 disposed on the outer surface of the insulating shielding layer, a second temperature of the optical fiber unit disposed in the polypropylene inner cushion layer, and a DC resistance of the conductor;

[0045] The second data acquisition module is used to acquire the thermal resistance of the conductor, the thermal resistance of each material layer and the third temperature of the optical fiber unit arranged 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 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;

[0047] 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.

[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 arranged on the outer surface of the insulating shielding layer, and average all the temperature values ​​of the optical fiber units arranged on the outer surface of the insulating shielding layer to generate a first temperature of the optical fiber units arranged 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 disposed in the polypropylene inner cushion layer, and average all temperature values ​​of the optical fiber units disposed in the polypropylene inner cushion layer to generate a second temperature of the optical fiber units disposed in the polypropylene inner cushion layer.

[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 executable on 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 as described in any one of the above method embodiments can be implemented.

[0053] Based on the above method item embodiments, the present invention provides a corresponding storage medium item 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] The embodiment of the present invention provides a method, device, electronic device and storage medium for optimizing the current carrying capacity of a multi-fiber built-in DC submarine cable. The method obtains the temperature data of the optical fiber units at different positions and the DC resistance of the conductor, and combines the thermal resistance information to monitor the working status of the submarine cable in real time. When the temperature exceeds the preset threshold, the thermal resistance data of the conductor and the material layer are further collected and the adjusted current carrying capacity is calculated, and finally the current carrying capacity of the submarine cable is optimized to ensure that it operates in the best state.

[0057] The present invention can comprehensively reflect the temperature field distribution of the submarine cable in a complex marine environment by setting optical fiber units in different material layers of the DC submarine cable to monitor temperature changes in real time. The current carrying capacity is dynamically calculated by combining the temperature data detected by the optical fiber unit with the thermal resistance information of each material layer, accurately revealing the relationship between the temperature change inside the submarine cable and the current carrying capacity, thereby solving the problem that the prior art cannot accurately capture the relationship between the temperature change of the submarine cable and the current carrying capacity, and lacks dynamic optimization means. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 It is a flow chart of a method for optimizing the current carrying capacity of a multi-fiber internal DC submarine cable provided by one embodiment of the present invention.

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

[0060] Figure 3 It is a structural schematic diagram of a current carrying capacity optimization device for a multi-fiber internal DC submarine cable provided by one 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 be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[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 built-in DC submarine cable, wherein the multi-fiber built-in DC submarine cable comprises a conductor 2 and a plurality of material layers, wherein the material layers include an insulating shielding layer 5 and a polypropylene inner cushion layer 10, and an optical fiber unit 1 is arranged at the center of the conductor 2, on the outer surface of the insulating shielding layer 5, and in the polypropylene inner cushion layer 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 schematic structural diagram of a multi-optical built-in DC submarine cable. The material layers of the multi-optical built-in DC submarine cable include, in addition to an insulating shielding layer 5 and a polypropylene inner cushion layer 10, 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-optical built-in DC submarine cable, from inside to outside, 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; the number of optical fiber units 1 arranged at the center of the conductor 2 is one; the number of optical fiber units 1 arranged on the outer surface of the insulating shielding layer 5 is four, and the four optical fiber units 1 are evenly distributed on the four equal points of the circumference; the number of optical fiber units 1 arranged in the polypropylene inner cushion layer 10 is four, and the four optical fiber units 1 are evenly distributed on the four equal points of the circumference; wherein each optical fiber unit 1 comprises 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 layer 10 are obtained by:

[0069] Obtaining the 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 unit 1 disposed on the outer surface of the insulating shielding layer 5 to generate a first temperature of the optical fiber unit 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 cushion layer 10 is obtained, and all temperature values ​​of the optical fiber unit 1 disposed in the polypropylene inner cushion layer 10 are averaged to generate a second temperature of the optical fiber unit 1 disposed in the polypropylene inner cushion layer 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 working band is 1550nm.

[0072] Step S2: When the first temperature or the second temperature exceeds the respective preset temperature threshold, obtain the thermal resistance of the conductor 2, the thermal resistance of each material layer, and the third temperature of the optical fiber unit 1 arranged 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 in the following manner:

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

[0075] According to the material parameters, extract 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;

[0076] The thermal resistance of the conductor 2 is calculated based on the outer radius of the structural layer of the conductor 2, the inner radius of the structural layer of the conductor 2 and the thermal conductivity of the conductor 2;

[0077] The thermal resistance of each material layer is calculated and generated 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.

[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 direct current submarine cable; wherein the first configuration file is provided with a modeling method for modeling the multi-fiber built-in direct current 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 internal DC submarine cable according to the modeling method in the first configuration file, and obtains 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 arranged in the simulated DC submarine cable; the finite element simulation software is COMSOL Multiphysics.

[0085] Obtain a second configuration file for injecting current into a 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 may 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 the fourth temperature of the optical fiber unit 1 disposed on the outer surface of the insulating shielding layer 5 and the fifth temperature of the optical fiber unit 1 disposed in the polypropylene inner cushion layer 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] Repeat the calibration operation until the difference between the first current value and the second current value is within a preset error threshold range, and generate an updated thermal resistance of the conductor 2 and an updated thermal resistance of each material layer;

[0090] The correction operation comprises:

[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, the second current value is 1900A, and 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, insulation layer thermal resistance from 0.002Ω·m 2 / K is adjusted to 0.0019Ω·m 2 / K, thermal resistance of polypropylene inner cushion layer 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, calculating and generating 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 calculation and generation of 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 by 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 by 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 sleeve 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 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 thermal resistance of the material and the 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 far 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 equation (4) and equation (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 embodiment, the present invention provides a corresponding device embodiment.

[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 acquire 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;

[0120] The second data acquisition module is used 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 arranged at the center of the conductor 2 when the first temperature or the second temperature exceeds the respective preset temperature threshold;

[0121] The current carrying capacity calculation module is used to calculate and generate 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;

[0122] 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.

[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 arranged on the outer surface of the insulating shielding layer 5, and average all the temperature values ​​of the optical fiber unit 1 arranged on the outer surface of the insulating shielding layer 5 to generate a first temperature of the optical fiber unit 1 arranged on the outer surface of the insulating shielding layer 5;

[0125] The second temperature acquisition unit is used to acquire the temperature value of each optical fiber unit 1 set in the polypropylene inner pad layer 10, and average all the temperature values ​​of the optical fiber unit 1 set in the polypropylene inner pad layer 10 to generate a second temperature of the optical fiber unit 1 set in the polypropylene inner pad layer 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 current carrying capacity optimization method 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 may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. In addition, in the accompanying 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 labor.

[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, wherein when the processor executes the computer program, the method for optimizing the current carrying capacity of a multi-fiber internal DC submarine cable as 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 implementing specific functions, which 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, a palmtop computer, 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, and uses various interfaces and lines to connect various parts of the entire terminal device.

[0132] The memory can be used to store the computer program and / or module, and the processor realizes various functions of the terminal device by running or executing the computer program and / or module 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 according to 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 (SecureDigital, SD) card, a flash card (Flash Card), at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0133] Based on the above method embodiment, the present invention provides a 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 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. 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 description with reference to the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" etc. means 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 one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.

[0137] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle 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 cushion 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 cushion layer; The method comprises: Obtaining a first temperature of an optical fiber unit disposed on an outer surface of the insulating shielding layer, a second temperature of an optical fiber unit disposed in a polypropylene inner cushion layer, and a DC resistance of a 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 the third temperature of the optical fiber unit arranged at the center of the conductor; Calculate and generate 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; According to the adjusted current-carrying capacity, the current-carrying capacity of the multi-fiber internal DC submarine cable is optimized.

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 cushion layer, 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 cushion layer 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, characterized in that: 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 the 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, characterized in that: 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; According to the material parameters, extract 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 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; 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 and generated 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.

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 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, the method further includes: Obtaining a first configuration file for modeling a multi-fiber built-in direct current submarine cable; wherein the first configuration file is provided with a modeling method for modeling the multi-fiber built-in direct current submarine cable according to the material parameters; Calling a preset finite element simulation software, so that the preset finite element simulation software models the multi-fiber internal DC submarine cable according to the modeling method in the first configuration file, and obtains a DC submarine cable finite element model; wherein the DC submarine cable finite element model includes a simulated DC submarine cable; and a simulated conductor is arranged in the simulated DC submarine cable; 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 the 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 comprises: Calculate and generate 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 range; if so, use the current thermal resistance of the conductor as the updated thermal resistance of the conductor; 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. The method for optimizing the current carrying capacity of a multi-fiber internal DC submarine cable according to claim 5, characterized in that: The step of 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: The first current carrying capacity is calculated by the following formula: 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 shielding layer; R T3 is the thermal resistance of the XLPE insulation layer; R T4 is the thermal resistance of the insulating shield; The second current carrying capacity is calculated by the following formula: 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 cushion; The smaller value of the first current carrying capacity and the second current carrying capacity is taken as the adjusted current carrying capacity.

7. A current carrying capacity optimization device for 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 disposed on the outer surface of the insulating shielding layer, a second temperature of the optical fiber unit disposed in the polypropylene inner cushion layer, and a DC resistance of the conductor; The second data acquisition module is used to acquire the thermal resistance of the conductor, the thermal resistance of each material layer and the third temperature of the optical fiber unit arranged 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 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; 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.

8. The current carrying capacity optimization device for a multi-fiber internal DC submarine cable according to claim 7, 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 arranged on the outer surface of the insulating shielding layer, and average all the temperature values ​​of the optical fiber units arranged on the outer surface of the insulating shielding layer to generate a first temperature of the optical fiber units arranged 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 disposed in the polypropylene inner cushion layer, and average all temperature values ​​of the optical fiber units disposed in the polypropylene inner cushion layer to generate a second temperature of the optical fiber units disposed in the polypropylene inner cushion layer.

9. 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 6.

10. 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 6.

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