Variable cross-section cable and aerial assembly suitable for high-altitude wind power generation

Abstract

The application relates to the technical field of high-altitude wind power generation, in particular to a variable cross-section cable suitable for high-altitude wind power generation and an air assembly. The variable cross-section cable comprises at least one variable cross-section unit, each of the variable cross-section units comprises a first cable, a first transition section and a second cable which are sequentially connected, the first cable and the second cable are in a cylindrical shape, the diameter of the cross section of the first cable is larger than that of the second cable, the first cable in the same variable cross-section unit is located below the second cable, a driver suitable for high-altitude wind power generation can move on the first cable and the second cable, the driver is connected with a canopy body and is used for driving the canopy body to open or close. The above technical scheme can effectively reduce the weight of the cable.

Description

Technical Field

[0001] This invention relates to the field of high-altitude wind power generation technology, and in particular to a variable cross-section cable and aerial components suitable for high-altitude wind power generation. Background Technology

[0002] High-altitude wind energy is a new energy source that humans have just begun to research and utilize. Some studies have pointed out that the wind energy contained in the upper atmosphere is more than 100 times the total energy needs of human society. Therefore, high-altitude wind power generation technology is the future development trend of wind power generation.

[0003] In related technologies, aerial components suitable for high-altitude wind power generation typically include cables and parachutes (such as power parachutes, balancing parachutes, etc.) and buoyancy devices (such as helium balloons, airships, etc.) mounted on the cables. However, the inventors discovered during the research and development process that aerial components in related technologies often suffer from excessive weight, with the weight of the cables potentially exceeding 50% of the aerial component's weight. This undoubtedly significantly restricts the power generation efficiency of high-altitude wind power generation systems.

[0004] Therefore, there is an urgent need to provide a variable cross-section cable and aerial components suitable for high-altitude wind power generation to solve the above-mentioned technical problems. Summary of the Invention

[0005] This invention provides a variable cross-section cable and aerial components suitable for high-altitude wind power generation, which can effectively reduce the weight of the cable.

[0006] In a first aspect, embodiments of the present invention provide a variable cross-section cable suitable for high-altitude wind power generation, comprising at least one variable cross-section unit. Each variable cross-section unit includes a first cable, a first transition section, and a second cable connected in sequence. Both the first cable and the second cable are cylindrical. The diameter of the cross-section of the first cable is larger than the diameter of the cross-section of the second cable. The first cable in the same variable cross-section unit is located below the second cable. An actuator suitable for high-altitude wind power generation can move on the first cable and the second cable. The actuator is connected to a canopy and is used to drive the canopy to open or close.

[0007] In one embodiment, the diameter of the first cable cross-section is equal to the maximum diameter of the first transition section cross-section, and the diameter of the second cable cross-section is equal to the minimum diameter of the first transition section cross-section.

[0008] In one embodiment, there are multiple variable cross-section units, with a second transition section connecting two adjacent variable cross-section units, and the second cable of the preceding variable cross-section unit is connected to the first cable of the following variable cross-section unit through the second transition section.

[0009] In one embodiment, the diameter of the second cable cross-section of the preceding variable cross-section unit is equal to the maximum diameter of the second transition section cross-section, and the diameter of the first cable cross-section of the following variable cross-section unit is equal to the minimum diameter of the second transition section cross-section.

[0010] In one embodiment, the first transition segment and the second transition segment adopt any of the following forming methods: braided fixing forming and sleeve fixing forming.

[0011] In one embodiment, the braiding and fixing process includes: disassembling the cable end with a small cross-sectional diameter and braiding the disassembled fiber bundles in the reverse direction into the cable body with a large cross-sectional diameter.

[0012] The sleeve fixing process includes fixing both ends of the sleeve to the ends of the first cable and the second cable connected to it, respectively; wherein the sleeve is made of carbon fiber reinforced titanium alloy composite material.

[0013] In one embodiment, the lengths of the first transition segment and the second transition segment are both related to the difference in cross-sectional diameter between the first cable and the second cable to which they are connected.

[0014] In one embodiment, the cross-sectional diameters of the first cable and the second cable are determined by the following formula:

[0015]

[0016] In the formula, d n C1 is the cross-sectional diameter of the nth cable, which is cylindrical when arranged from top to bottom; S is the preset coefficient related to the strength of the cable material; T is the preset safety factor; i The maximum tension of the i-th cylindrical cable when arranged from top to bottom; ρ is the air density; C t A second preset coefficient related to the umbrella's structural parameters, including shape, air permeability, air density, Reynolds number, wind direction, and the angle between the cable and the horizontal line; A i V is the nominal area of ​​the i-th umbrella; i,w β is the wind speed at the height of the i-th umbrella; β is the angle between the cable and the horizontal line; V R The speed is the cable speed.

[0017] In one embodiment, fiber optic sensors are installed in both the first transition section and the second transition section. These sensors monitor the strain and temperature of the cable. The sensors are electrically connected to an external controller, which performs the following operations:

[0018] Acquire monitoring data for all transition sections at the current moment; wherein, the monitoring data includes wind speed and cable strain, temperature, diameter, velocity, angle with the horizontal line, creep coefficient and fatigue parameters;

[0019] The monitoring data is input into a pre-trained stress prediction model, and the stress prediction trend corresponding to each transition segment is output; wherein, the stress prediction model is trained based on an LSTM model;

[0020] Based on the predicted stress trend and the tension of the umbrella, a cable winding strategy is determined.

[0021] Secondly, embodiments of the present invention provide an aerial component suitable for a high-altitude wind power generation system, including a cable and a parachute and a levitation device disposed on the cable, wherein the cable is a variable cross-section cable as described in any of the above embodiments.

[0022] Compared with related technologies, the present invention has at least the following beneficial effects:

[0023] The variable cross-section cable and aerial components for high-altitude wind power generation provided by embodiments of the present invention utilize a variable cross-section design for the cable, where the cable diameter decreases towards the top, while maintaining a constant cable cross-sectional diameter throughout the actuator's stroke. A first transition section with a variable cross-section is provided between the two actuators. This minimizes cable weight and effectively improves the power generation efficiency of the high-altitude wind power generation system. Therefore, the above technical solution effectively reduces cable weight. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 A schematic diagram of the structure of a variable cross-section cable suitable for high-altitude wind power generation provided in an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the structure of an aerial component suitable for high-altitude wind power generation, provided as an embodiment of the present invention.

[0027] Figure label:

[0028] 10-Cable; 20-Actuator; 30-Parasol; 40-Flying device;

[0029] 1-Variable cross-section unit; 11-First cable; 12-First transition section; 13-Second cable;

[0030] 2-Second transition section. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] like Figure 1 and Figure 2 As shown, this embodiment of the invention provides a variable cross-section cable suitable for high-altitude wind power generation, including at least one variable cross-section unit 1. Each variable cross-section unit 1 includes a first cable 11, a first transition section 12, and a second cable 13 connected in sequence. Both the first cable 11 and the second cable 13 are cylindrical. The diameter of the cross-section of the first cable 11 is larger than the diameter of the cross-section of the second cable 13. The first cable 11 in the same variable cross-section unit 1 is located below the second cable 13. A drive 20 suitable for high-altitude wind power generation can move on the first cable 11 and the second cable 13. The drive 20 is connected to the umbrella body 30 and is used to drive the umbrella body 30 to open or close.

[0033] In this embodiment, by designing a variable cross-section cable suitable for high-altitude wind power generation—that is, the cable diameter decreases towards the top, while maintaining a constant cable cross-sectional diameter throughout the actuator's stroke—and by incorporating a first transition section with a variable cross-section between the two actuators, the cable weight can be minimized, thereby effectively improving the power generation efficiency of the high-altitude wind power generation system. Therefore, the above technical solution effectively reduces the cable weight.

[0034] Understandably, the end of the second cable 13 in the uppermost variable cross-section unit 1 is used to connect to the buoyancy device.

[0035] In one embodiment of the present invention, the diameter of the cross-section of the first cable 11 is equal to the maximum diameter of the cross-section of the first transition section 12, and the diameter of the cross-section of the second cable 13 is equal to the minimum diameter of the cross-section of the first transition section 12. This arrangement not only effectively ensures the load transfer efficiency between the first cable 11 and the second cable 13, but also effectively prevents stress concentration in the cables.

[0036] In one embodiment of the present invention, there are multiple variable cross-section units 1, and a second transition section 2 connects two adjacent variable cross-section units 1. The second cable 13 of the preceding variable cross-section unit 1 is connected to the first cable 11 of the following variable cross-section unit 1 through the second transition section 2. This arrangement ensures that multiple sets of umbrella bodies can be installed on the cable to minimize the overall weight of the cable.

[0037] In one embodiment of the present invention, the diameter of the cross-section of the second cable 13 of the preceding variable cross-section unit 1 is equal to the maximum diameter of the cross-section of the second transition section 2, and the diameter of the cross-section of the first cable 11 of the following variable cross-section unit 1 is equal to the minimum diameter of the cross-section of the second transition section 2. This arrangement not only effectively ensures the load transfer efficiency between two adjacent variable cross-section units 1, but also effectively prevents stress concentration in the cables.

[0038] In one embodiment of the present invention, the first transition section 12 and the second transition section 2 adopt any of the following forming methods: weaving and fixing forming, sleeve fixing forming.

[0039] It should be noted that when using a braided fixing method, the number of fibers in the transition section can decrease exponentially (i.e., non-uniformly), which allows for a smoother stress transfer. Furthermore, the fiber crossing angle can be gradually changed from 30° (high stiffness zone) to 55° (high toughness zone), thereby improving the cable's shear resistance. When using a sleeve fixing method, the transition section can employ a 7° cone angle design, which ensures efficient load transfer without causing shear failure of the adhesive layer due to an excessively small angle.

[0040] In some embodiments, the first transition section 12 and the second transition section 2 may be frustum-shaped (when a sleeve is used for fixing and forming) or hyperbola-shaped (when a braid is used for fixing and forming), and no specific limitation is made here.

[0041] In one embodiment of the present invention, the braiding and fixing process includes: disassembling the cable end with a smaller cross-sectional diameter and weaving the disassembled fiber bundles back into the cable body with a larger cross-sectional diameter. This arrangement creates a frustum-shaped transition section that smoothly transitions from thin to thick, allowing for gentler stress transmission and preventing excessive stress concentration.

[0042] In one embodiment of the present invention, the sleeve fixing and forming includes: fixing both ends of the sleeve (not shown in the figure) to the ends of the first cable 11 and the second cable 13 connected thereto, respectively; wherein the sleeve is made of carbon fiber reinforced titanium alloy composite material. This arrangement facilitates the forming of variable cross-section cables, and the use of carbon fiber reinforced titanium alloy composite material for the sleeve can further reduce the overall weight of the cable while ensuring the structural strength of the transition section.

[0043] It is understood that the embodiments of the present invention do not specifically limit the fixing method at both ends of the sleeve, as long as the fixed connection between the sleeve and the cable can be achieved.

[0044] In one embodiment of the present invention, the lengths of the first transition section 12 and the second transition section 2 are both related to the difference in cross-sectional diameter between the first cable 11 and the second cable 13 to which they are connected.

[0045] Understandably, the length of the transition section is a key factor in determining the degree of stress concentration. Generally speaking, the maximum stress point will appear in the uniform diameter section (i.e., the non-transition section). Therefore, the length of the transition section can be optimized based on the difference in cross-sectional diameter between the first cable 11 and the second cable 13 to avoid stress concentration.

[0046] In one embodiment of the present invention, the cross-sectional diameters of the first cable 11 and the second cable 13 are determined by the following formula:

[0047]

[0048] In the formula, d n C1 is the cross-sectional diameter of the nth cable, which is cylindrical when arranged from top to bottom; S is the preset coefficient related to the strength of the cable material; T is the preset safety factor; i The maximum tension of the i-th cylindrical cable when arranged from top to bottom; ρ is the air density; C t A second preset coefficient related to the umbrella's structural parameters, including shape, air permeability, air density, Reynolds number, wind direction, and the angle between the cable and the horizontal line; A i V is the nominal area of ​​the i-th umbrella; i,w β is the wind speed at the height of the i-th umbrella; β is the angle between the cable and the horizontal line; V R The speed is the cable speed.

[0049] In this embodiment, considering the safe operation of the cable, the diameter of the cylindrical cable cross-section needs to be directly related to the breaking strength of the cable. The breaking strength of the cable is related to the tension of the umbrella body. Therefore, after introducing a first preset coefficient and a preset safety factor related to the strength of the cable material, a mapping relationship between the diameter of the cylindrical cable cross-section and the tension of the umbrella body is established, thereby obtaining the optimized cable diameter.

[0050] In one embodiment of the present invention, fiber optic sensors (not shown in the figure) are provided in both the first transition section 12 and the second transition section 2. The fiber optic sensors are used to monitor the strain and temperature of the cable. The fiber optic sensors are electrically connected to an external controller, which is used to perform the following operations:

[0051] Acquire monitoring data for all transition sections at the current moment; the monitoring data includes wind speed, cable strain, temperature, diameter, velocity, angle with the horizontal line, creep coefficient, and fatigue parameters;

[0052] The monitoring data is input into a pre-trained stress prediction model, and the output is the stress prediction trend corresponding to each transition segment; the stress prediction model is trained based on an LSTM model.

[0053] Based on the predicted stress trend and the tension of the umbrella, a cable winding strategy is determined.

[0054] In this embodiment, by setting fiber optic sensors in the transition section, the strength of the cable structure can be effectively monitored and predicted in real time, thereby ensuring the safe operation of the cable.

[0055] It is understood that the embodiments of the present invention do not specifically limit the cable winding strategy, as long as the safe operation of the cable can be guaranteed.

[0056] In addition, embodiments of the present invention also provide an aerial component suitable for a high-altitude wind power generation system, including a cable 10 and a parachute 30 and a levitation device 40 disposed on the cable 10, wherein the cable 10 is a variable cross-section cable mentioned in any of the above embodiments.

[0057] It is understood that the aerial components for high-altitude wind power generation systems provided in the embodiments of the present invention and the variable cross-section cables for high-altitude wind power generation provided in the above embodiments are based on the same inventive concept, and therefore have the same beneficial effects. The beneficial effects of the aerial components for high-altitude wind power generation systems will not be elaborated here.

[0058] In some embodiments, the umbrella body 30 can be a power umbrella or a balancing umbrella, without specific limitations.

[0059] In some embodiments, the levitation device 40 may be a helium balloon or other device with levitation function, and no specific limitation is made here.

[0060] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0061] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is only used to illustrate the technical solution of the present invention, and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A variable cross-section cable suitable for high-altitude wind power generation, characterized in that, It includes at least one variable cross-section unit, each of which includes a first cable, a first transition section, and a second cable connected in sequence. Both the first cable and the second cable are cylindrical, and the diameter of the cross-section of the first cable is larger than the diameter of the cross-section of the second cable. The first cable in the same variable cross-section unit is located below the second cable. An actuator suitable for high-altitude wind power generation can move on the first cable and the second cable. The actuator is connected to the umbrella body and is used to drive the umbrella body to open or close. The diameter of the first cable cross section is equal to the maximum diameter of the first transition section cross section, and the diameter of the second cable cross section is equal to the minimum diameter of the first transition section cross section. A second transition section connects two adjacent variable cross-section units, and the second cable of the previous variable cross-section unit is connected to the first cable of the next variable cross-section unit through the second transition section. The diameter of the second cable cross section of the previous variable cross section unit is equal to the maximum diameter of the second transition section cross section, and the diameter of the first cable cross section of the subsequent variable cross section unit is equal to the minimum diameter of the second transition section cross section. The lengths of the first transition section and the second transition section are both related to the difference in cross-sectional diameter between the first cable and the second cable to which they are connected; The cross-sectional diameters of the first and second cables are determined by the following formula: In the formula, d n The first one is cylindrical when arranged from top to bottom. n The cross-sectional diameter of the cable; C 1 is a first preset coefficient related to the strength of the cable material; S Preset safety factor; T i The first one is cylindrical when arranged from top to bottom. i The maximum tensile force of each cable; ρ air density; C t The second preset coefficient is related to the structural parameters of the umbrella, including shape, air permeability, air density, Reynolds number, wind direction, and the angle between the cable and the horizontal line. A i For the first i The nominal area of ​​each umbrella structure; V i,w For the first i Wind speed at the height of the umbrella; β The angle between the cable and the horizontal line; V R For cable speed; Both the first transition section and the second transition section are equipped with fiber optic sensors. These sensors are used to monitor the strain and temperature of the cable. The fiber optic sensors are electrically connected to an external controller, which performs the following operations: Acquire monitoring data for all transition sections at the current moment; wherein, the monitoring data includes wind speed and cable strain, temperature, diameter, velocity, angle with the horizontal line, creep coefficient and fatigue parameters; The monitoring data is input into a pre-trained stress prediction model, and the stress prediction trend corresponding to each transition segment is output; wherein, the stress prediction model is trained based on an LSTM model; Based on the predicted stress trend and the tension of the umbrella, a cable winding strategy is determined.

2. The variable cross-section cable according to claim 1, characterized in that, The first transition section and the second transition section adopt any of the following forming methods: weaving and fixing forming, sleeve fixing forming.

3. The variable cross-section cable according to claim 2, characterized in that, The braiding and fixing process includes: disassembling the ends of the cable with a small cross-sectional diameter and weaving the disassembled fiber bundles back into the main body of the cable with a large cross-sectional diameter; The sleeve fixing process includes fixing both ends of the sleeve to the ends of the first cable and the second cable connected to it, respectively; wherein the sleeve is made of carbon fiber reinforced titanium alloy composite material.

4. An aerial component suitable for high-altitude wind power generation systems, characterized in that, It includes a cable and a parachute and a levitation device disposed on the cable, wherein the cable is a variable cross-section cable as described in any one of claims 1-3.

Images