A floating body system with adaptive cable expansion and contraction

Abstract

The present invention provides a cable adaptive telescopic floating system, comprising a plurality of floating units sleeved on the cable, wherein a cavity is arranged in the floating unit, a block is arranged in the cavity, one end of the block is connected to the inner wall of the cavity through a spring and a damper, the other end of the block is arc-shaped and is provided with a plurality of slip rings, and the cable is movably arranged in the slip ring. A block is arranged in the floating unit of the present invention, and the block is connected to the inner wall of the cavity through a spring and a damper, so that the cable connected to the block can adaptively adjust the length of the cable according to the change of the water level on the water surface, and reduce the influence of strong winds and waves on the force of the cable, so as to ensure the connection reliability at the cable joint. Compared with the traditional S-shaped laying method, it can significantly save the number of floating bodies, save the cable line corridor, improve the laying aesthetics, and do not need to increase additional labor costs.

Description

Technical Field

[0001] The invention relates to the technical field of water photovoltaics, and in particular to a floating body system with self-adaptive telescopic and adjustable cables. Background Art

[0002] With the rapid development of the photovoltaic industry and the country's strict control of land resources, the land resources available for the construction of photovoltaic power stations are becoming increasingly tight. Water-based photovoltaic power stations can save land resources. At the same time, the cooling effect of water on photovoltaic modules can reduce the surface temperature of the modules, reduce cable line losses and increase the power generation of the power station. In addition, the water photovoltaic array can also block the water surface, thereby inhibiting the growth of algae and improving water quality. Therefore, water-based photovoltaic power stations have ushered in a long-term development. In particular, compared with pile-driven photovoltaics, floating photovoltaics on the water surface have greater advantages in scenes such as deep water, large water level fluctuations, and unstable underwater geology. In addition, floating photovoltaics on the water are more convenient to construct and operate, and there is a floating channel dedicated to operation and maintenance, and there is no need to equip maintenance ships like pile-driven photovoltaics.

[0003] Usually, the cables between various devices and components are laid on floating bodies. Considering the influencing factors such as water level, wind and waves, conventional surface photovoltaics usually reserve a certain length of cable when laying cables and lay them in the form of S-bends. However, this laying plan will increase the number of cable floats used and occupy more cable line corridors. At the same time, it cannot adapt to the influence of factors such as water level, wind and waves, and needs to be adjusted manually. In particular, the floating body will vibrate intermittently due to factors such as wind and waves, causing the cable to be repeatedly bent and damaged. Summary of the invention

[0004] The purpose of the present invention is to provide a floating body system with self-adaptive telescopic cable to address the defects of the prior art.

[0005] The present invention provides a cable adaptive telescopic and adjustable floating body system, comprising a plurality of floating body units sleeved on a cable, wherein a cavity is arranged in the floating body unit, a block is arranged in the cavity, one end of the block is connected to the inner wall of the cavity through a spring and a damper, the other end of the block is arc-shaped and is provided with a plurality of slip rings, and the cable is movably arranged in the slip ring.

[0006] The present invention provides a stopper in the floating unit, which is connected to the inner wall of the cavity through a spring and a damper, so that the cable connected to the stopper can adaptively adjust the length of the cable according to the change of the water level, reduce the influence of strong winds and waves on the cable, and ensure the connection reliability of the cable joint. Compared with the traditional S-shaped laying method, it can significantly save the number of floating bodies, save cable line corridors, improve the aesthetics of laying, and do not need to increase additional labor costs.

[0007] Furthermore, the radius r of the arc-shaped end of the stopper is greater than the turning radius R of the cable.

[0008] The present invention limits the radius r of the arc-shaped end of the stopper, which can prevent the cable from being damaged due to excessive bending angle during the extension and retraction process.

[0009] Furthermore, openings are provided at both ends of the floating unit, the openings are connected to the cavity, one end of the cable enters the cavity through one of the openings, and leaves the cavity from the other opening through a slip ring on the stopper, and the openings are arc-shaped.

[0010] The present invention sets the opening of the floating unit in an arc shape, which can effectively prevent the cable sheath and insulation from being damaged.

[0011] Furthermore, the elastic coefficient of the spring Among them, F is the maximum tension that the cable can withstand, a is the length of the floating unit, b is the width of the floating unit, l is the maximum contraction of the spring, and M is the bending moment of the cable at the block.

[0012] The spring of the present invention determines the elastic coefficient according to the maximum pulling force that the cable can withstand, thereby preventing the cable from being subjected to excessive force.

[0013] Furthermore, the damper includes a velocity damper and a damping spring, and the viscosity coefficient of the velocity damper is c 0 , the elastic coefficient of the damping spring is k 0 , then the damper natural frequency f 0 and damping ζ 0 for Among them, m 0 is the weight of the stopper and the corresponding part of the cable on the stopper.

[0014] Further, Among them, f 1 is the typical excitation frequency of the cable, s is the typical excitation frequency of the cable f 1 and the damper natural frequency f 0 ratio.

[0015] The present invention utilizes the typical excitation frequency f of the cable 1 and the damper natural frequency f 0 The ratio requirement can be adjusted for the damper natural frequency f 0 The value of Determine the elastic constant of the damping spring as k 0 and the viscosity coefficient of the velocity damper is c 0 .

[0016] Furthermore, the ratio of the cable laying length to the total length of all buoys is λ, and λ must satisfy

[0017] The present invention can obtain the total length of all floating bodies by calculating λ, thereby determining the required number of floating bodies to meet the cable expansion and contraction requirements to adapt to the influence of water level changes, strong winds and waves.

[0018] The beneficial effects of the present invention are as follows: when the tension on the cable changes due to the rise and fall of the water level, the pressure on the spring from the cable arc baffle will also change, thereby adaptively expanding and contracting and adjusting the length of the cable to prevent the cable and the cable terminal from being damaged by excessive force. When the tension on the cable changes periodically and intermittently due to factors such as wind and waves on the water surface, the damper will weaken the tortuosity of the cable to prevent the cable from being damaged by repeated tortuosity. Compared with the traditional S-shaped laying method, the present invention can significantly save the number of floats, save cable line corridors, and improve the aesthetics of the laying. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of the floating unit of the present invention;

[0020] Figure 2 This is a structural dimension diagram of the floating unit of the present invention;

[0021] Figure 3 is a topological diagram of the damper of the present invention;

[0022] Figure 4 It is a schematic diagram of a floating unit with adaptively retractable cables in different states of the present invention;

[0023] Figure 5 It is a structural schematic diagram of the floating body system of the present invention;

[0024] Figure 6 It is a force diagram of the spring of the present invention.

[0025] Reference numerals: floating unit 1; damper 2; spring 3; stopper 4; semi-fixed buckle 5; slip ring 6; cavity 7; cable 8. DETAILED DESCRIPTION

[0026] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0027] like Figure 5 As shown, this embodiment provides a floating body system with adaptive telescopic cable adjustment, including a plurality of floating body units 1 sleeved on a cable 8.

[0028] like Figure 1 , 2As shown, the floating unit 1 is plate-shaped as a whole, with a length of a and a width of b. A cavity 7 is provided in the floating unit 1, and the cavity 7 is in the shape of an arrow. A stopper 4 is provided in the cavity 7, and the stopper 4 is close to the head of the arrow-shaped cavity 7. One end of the stopper 4 is connected to the inner wall of the cavity 7 through a spring 3 and a damper 2. The damper 2 is arranged at the tail of the arrow-shaped cavity 7. The other end of the stopper 4 is arc-shaped and fixed with a plurality of slip rings 6 and a semi-fixed buckle 5. The plurality of slip rings 6 are evenly arranged along the length direction of the floating unit 1, and the semi-fixed buckle 5 is fixed in the middle of the stopper 4. Openings are provided at both ends of the floating unit 1, and the openings are connected with the cavity 7. One end of the cable 8 enters the cavity 7 through one of the openings, and leaves the cavity 7 from the other opening through the slip ring 6 and the semi-fixed buckle 5 on the stopper 4. The opening is arc-shaped, and the semi-fixed buckle 5 is used to limit the vertical position of the cable, that is, the cable can only move along the length direction, but cannot move in the direction perpendicular to the sea surface.

[0029] It is understandable that when the tension on the cable 8 changes due to the rise and fall of the water level, the length of the cable path between the devices will change, and the pressure on the arc-shaped baffle of the cable 8 by the spring 3 will also change, thereby adaptively expanding and contracting and adjusting the length of the cable 8 to prevent the cable 8 and the cable terminal from being damaged by excessive force. For example, when the wind and waves are strong, the floating unit 1 will be offset by the wind. If the cable cannot be released to a certain length, it will be pulled by the floating unit 1, which may easily cause the cable connector to fall off or even break the cable. When the tension on the cable 8 changes periodically and intermittently due to factors such as wind and waves on the water surface, the damper 2 will weaken the tortuosity of the cable 8 to prevent the cable 8 from being damaged by repeated tortuosity.

[0030] In the prior art, cables are laid in an S-bend. When the same cable length is laid in an S-bend, the number of floating units required is the cable length divided by the cable length in the floating unit. In the present embodiment, the cable is in an Ω shape in the floating unit 1. Therefore, the cable in each section of the floating unit 1 is longer than that of the traditional floating unit. Therefore, the number of floating units 1 used can be saved.

[0031] In this embodiment, the radius r of the arc-shaped end of the stopper 4 is greater than the turning radius R of the cable 8. According to the "Design Specifications for Power Engineering Cables 8" (GB 50217-2018), when the outer diameter of the cable 8 is D, the radius r of the stopper 4 should satisfy r>c 1 D, where c 1 It is the minimum bending radius coefficient of cable 8. Its value is related to the form and number of cores of cable 8. The specific value is shown in the table below:

[0032]

[0033]

[0034] It is necessary to comprehensively consider the influencing factors such as the stress characteristic F of the cable 8, the water surface level, wind force and waves, and design the parameters of the spring 3 and the damper 2 to ensure that the spring 3 can meet the contraction and extension of the cable 8 under different working conditions, and the damper 2 can damp the influence of strong winds and waves, thereby ensuring the connection reliability at the joint of the cable 8.

[0035] like Figure 6 As shown in the figure, when the tension and bending moment of the cable act on the arc baffle, the arc baffle will be subjected to downward pressure, thereby compressing the spring. When the tension of the cable reaches the maximum value F, the compression of the spring also reaches the maximum. Therefore, in order for the pressure on the cable not to exceed the maximum value F, the compression of the spring cannot exceed the maximum compression value l. According to the force diagram, it can be obtained:

[0036]

[0037]

[0038] Calculate the elastic coefficient of spring 3 Wherein, F is the maximum tension that the cable 8 can withstand, a is the length of the floating unit 1, b is the width of the floating unit 1, l is the maximum contraction of the spring 3, and M is the bending moment of the cable 8 at the stopper 4. The elastic coefficient of the spring 3 obtained by the above calculation can avoid excessive compression of the spring 3, which causes the tension on the cable 8 to exceed the maximum tension F.

[0039] The damper 2 needs to be designed for the vibration frequency of strong winds and waves to weaken the bending changes of the cable 8 and prevent the cable 8 from being damaged by repeated bending. Figure 3 As shown, the damper 2 includes a velocity damper and a damping spring. The viscosity coefficient of the velocity damper is c 0 , the elastic coefficient of the damping spring is k 0 , then the natural frequency of damper 2 is f 0 and damping ζ 0 for Among them, m 0 is the weight of the stopper 4 and the corresponding portion of the cable 8 on the stopper 4.

[0040] Generally, the typical excitation frequency f of strong wind and waves is required 1 and the natural frequency f of damper 2 0 The ratio s between them satisfies the following relationship Among them, f 1 The empirical mode decomposition method can be used to obtain the damping ζ 0 The value is between 0.3 and 0.4, through the damping ζ 0 Values ​​and typical excitation frequencies f of strong winds and waves 1 The value of the damper 2 natural frequency f 0 ,pass Then we can get k 0 and c 0 .

[0041] The number of floating units 1 used can be calculated by the ratio λ of the laying length of the cable 8 to the total length of all floating units, and λ must satisfy By calculating λ, the total length of all the floating bodies can be obtained, thereby determining the required number of floating bodies to meet the expansion and contraction requirements of the cable 8 to adapt to the influence of water level changes, strong winds and waves.

[0042] The present invention proposes a cable adaptive telescopic adjustable floating body method and system, which can adapt to the influence of factors such as water surface water level, wind force and waves and adjust the length of cable 8. Compared with the traditional S-shaped laying method, the present invention can significantly save the number of floating bodies, save the cable 8 line corridor, and improve the laying aesthetics. At the same time, the present invention can adaptively adjust the length of cable 8 to adapt to and damp the influence of water surface water level changes, strong winds and waves, etc., without adding additional labor costs, ensuring the connection reliability of the cable 8 joint and saving labor costs.

[0043] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A floating system with adaptive cable expansion and contraction, Features: The invention comprises a plurality of floating units (1) sleeved on a cable (8), wherein a cavity (7) is arranged in the floating unit (1), a stopper (4) is arranged in the cavity (7), one end of the stopper (4) is connected to the inner wall of the cavity (7) via a spring (3) and a damper (2), the other end of the stopper (4) is arc-shaped and is provided with a plurality of slip rings (6), and the cable (8) is movably arranged in the slip ring (6); The damper (2) comprises a velocity damper and a damping spring, wherein the viscosity coefficient of the velocity damper is c 0 , the elastic coefficient of the damping spring is k 0 , then the natural frequency of the damper (2) is f 0 and damping ζ 0 for Among them, m 0 is the weight of the stopper (4) and the corresponding portion of the cable (8) on the stopper (4); Among them, f 1 is the typical excitation frequency of strong wind and waves, s is the typical excitation frequency of strong wind and waves f 1 and the damper (2) natural frequency f 0 ratio.

2. The cable adaptive telescopic and adjustable floating body system according to claim 1, Features: The radius r of one arc-shaped end of the stopper (4) is greater than the turning radius R of the cable (8).

3. The cable adaptive telescopic and adjustable floating body system according to claim 1, Features: The floating unit (1) is provided with openings at both ends, the openings being connected to the cavity (7), one end of the cable (8) enters the cavity (7) through one of the openings, and leaves the cavity (7) from the other opening through a slip ring (6) on the stopper (4), and the openings are arc-shaped.

4. The cable adaptive telescopic and adjustable floating body system according to claim 1, Features: The elastic coefficient of the spring (3) where F is the maximum tensile force that the cable (8) can withstand, a is the length of the floating body unit (1), b is the width of the floating body unit (1), l is the maximum contraction amount of the spring (3), and M is the bending moment of the cable (8) at the stop block (4).

5. The cable adaptive telescopic and adjustable floating body system according to claim 1, Features: The ratio of the laying length of the cable (8) to the total length of all floating bodies is λ, and λ must satisfy

Images