A flexible ice-resistant structure suitable for offshore wind power pile foundation

Abstract

A flexible ice-resistant structure suitable for offshore wind power pile foundations comprises a pile foundation, within the action range of fixed ice and drifting ice on the pile foundation, a fixedly connected shrinkable capsule is arranged around the pile foundation, the shrinkable capsule is made of flexible material, and an inlet valve is arranged on the shrinkable capsule. By arranging the shrinkable capsule on the periphery of the pile foundation, different media are filled in the capsule to change the frequency of the original pile foundation, forming a damper to change the frequency of the pile foundation to the impact frequency of drifting ice, so as to avoid resonance of the wind turbine caused by ice-induced vibration, and detecting the impact frequency of drifting ice in each flow direction and the vibration frequency of the pile foundation through floating ice vibration sensors and pile foundation vibration sensors, it can be adjusted in real time according to actual conditions, has a high degree of intelligence, can be shrunk to be close to the pile foundation when there is no ice layer, and will not increase the force of waves and water flow on the pile foundation due to the increase in cross-sectional area. The structure is suitable for use on offshore foundation structures.

Description

Technical Field

[0001] The present invention relates to the technical field of offshore wind power engineering, and in particular to a flexible ice-resistant structure suitable for offshore wind power pile foundations. Background Art

[0002] As the country continues to strengthen its support for new energy, the concept of green development has been further implemented, and a large number of offshore wind power projects are also in full swing. my country's offshore wind power construction has been fully launched, including the construction of multiple wind farms in the Bohai Sea. In winter, there is sea ice intrusion in the Bohai Bay, which has a serious impact on the foundation of wind turbines. Not only does it have a large static effect, but it also causes ice-induced vibration of the structure at a specific flow rate. This will not only reduce power generation and cause economic losses, but may even cause structural failure and safety problems. In addition, the anti-ice cone structure used in the offshore platform can solve the above problems, but this method causes a large increase in the cost of the wind turbine foundation, and greatly increases the construction difficulty and construction period.

[0003] There are also corresponding anti-ice measures in the prior art. For example, Chinese patent document CN 204267229U records an ice-breaking and shock-absorbing device for the foundation structure of an offshore wind turbine. The device is arranged at the ice-breaking foundation position through a bracket, a connecting plate and a connecting bolt. The ice-breaking cone converts the sea ice damage from extrusion-type damage to bending-type damage to reduce the damage to the foundation structure. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a flexible ice-resistant structure suitable for offshore wind power pile foundations, which utilizes a flexible mechanism to form a damper to change the frequency of the pile foundation to avoid the impact frequency of drifting ice, thereby avoiding resonance of the wind turbine caused by ice-induced vibration.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A flexible ice-resistant structure suitable for offshore wind power pile foundations comprises a pile foundation. Within the action range of fixed ice and floating ice on the pile foundation, a fixedly connected shrinkable bladder is arranged around the pile foundation. The shrinkable bladder is made of flexible material and is provided with an inlet valve. According to the interaction between the fixed ice, floating ice and the pile foundation, a medium is filled into the shrinkable bladder through the inlet valve to change the shape and internal pressure of the shrinkable bladder, so that the overall frequency characteristics of the shrinkable bladder are changed to avoid ice-induced vibration.

[0007] The above-mentioned shrinkable bladder is in the shape of a ring, the inner side of the ring is fixedly connected to the outer side of the pile foundation, and the outer side of the ring is a deformation part that contacts the external ice layer.

[0008] The above-mentioned collapsible bladder is also provided with a discharge valve for discharging the medium to the outside.

[0009] The medium filled in the above-mentioned shrinkable bladder is gas or liquid.

[0010] In a preferred embodiment, an axial partition is provided in the above-mentioned shrinkable bladder along the axial direction of the pile foundation, and the axial partition is sealed and connected to the upper and lower layers of the shrinkable bladder in the axial direction to divide the shrinkable bladder into different chambers, each of which is provided with an inlet valve and an outlet valve.

[0011] In a preferred embodiment, the above-mentioned axial partitions are provided in plurality, dividing the internal space of the shrinkable sac into a plurality of different chambers. The outermost chamber of the shrinkable sac is a buffer chamber, which is filled with gas as the medium for buffering the action of flowing ice. The inner chamber is a pressurized chamber, which is filled with liquid or gas as the medium for changing the overall frequency characteristics of the shrinkable sac with a medium of specific pressure.

[0012] In a preferred solution, a fixedly connected floating ice vibration sensor is provided on the outside of the above-mentioned pile foundation, and the floating ice vibration sensor is fixedly connected to the pile foundation by a connecting rod structure. The floating ice vibration sensor is located at the position of the ice layer in the vertical direction and is used to sense the impact frequency of the floating ice. A fixedly connected pile foundation vibration sensor is provided on the inside of the pile foundation and is used to sense the swing frequency of the pile foundation.

[0013] In a preferred embodiment, four radial partitions are provided in the radial plane along the pile foundation inside the above-mentioned shrinkable bladder body, and the radial partitions are sealed and connected to the upper and lower layers of the shrinkable bladder body in the axial direction, dividing the interior of the shrinkable bladder body into four parts in the radial direction. The axial partitions and the radial partitions are combined to divide the shrinkable bladder body into different radial partitions and axial partitions, and each of the separated bladder chambers is provided with an inlet valve and an outlet valve.

[0014] In a preferred embodiment, the buffer chamber is filled with medium by a buffer pump, the pressurized chamber is filled with medium by a pressurized pump, the buffer pump motor is regulated by a buffer pump driver, and the pressurized pump motor is regulated by a pressurized pump driver.

[0015] The above-mentioned buffer pump driver and charging pump driver are electrically connected to the output end of the controller, and the output end of the controller is also electrically connected to each inlet valve and outlet valve. The floating ice vibration sensor and the pile foundation vibration sensor are electrically connected to the input end of the controller. The controller controls the buffer pump and the charging pump according to the received floating ice impact frequency and pile foundation vibration frequency, and then adjusts each capsule chamber.

[0016] The present invention provides a flexible ice-resistant structure suitable for offshore wind power pile foundations. A shrinkable capsule is arranged on the periphery of the pile foundation, and different media are filled in the capsule to change the frequency of the original pile foundation, so as to form a damper to change the frequency of the pile foundation to match the impact frequency of drifting ice, so as to avoid resonance of the wind turbine set caused by ice-induced vibration. The impact frequency of drifting ice in each flow direction and the vibration frequency of the pile foundation can be detected by a floating ice vibration sensor and a pile foundation vibration sensor. The amount and pressure of the medium filled in each capsule chamber can be changed by a control device, so as to change the natural frequency, and the influence of the impact on the pile body can be reduced by the damping effect of the buffer capsule chamber. The structure can be adjusted in real time according to actual conditions, has a high degree of intelligence, can be shrunk to fit closely to the pile foundation when there is no ice layer, and will not increase the force of the ocean current on the pile foundation due to the increase in cross-sectional area. The structure is suitable for use on offshore foundation structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0018] Figure 1 It is a schematic diagram of the flexible anti-icing structure of the present invention;

[0019] Figure 2 It is a schematic diagram of the flexible anti-icing structure in the state of being filled with medium;

[0020] Figure 3 It is a schematic diagram of the structure with axial partition in the preferred embodiment;

[0021] Figure 4 for Figure 3 Schematic diagram of radial section;

[0022] Figure 5 It is a structural schematic diagram of the preferred solution with a sensor;

[0023] Figure 6 for Figure 5 Schematic diagram of radial section;

[0024] Figure 7 It is a schematic diagram of a radial cross section with radial interlayers in the preferred embodiment;

[0025] Figure 8 This is the control principle diagram of the preferred solution.

[0026] In the figure: pile foundation 1, collapsible bladder 2, inlet valve 3, outlet valve 4, axial partition 5, buffer chamber 6, pressurized chamber 7, floating ice vibration sensor 8, pile foundation vibration sensor 9, radial partition 10, controller 11, buffer pump 12, charging pump 13, buffer pump driver 14, charging pump driver 15. DETAILED DESCRIPTION

[0027] like Figure 1As shown in the figure, a flexible ice-resistant structure suitable for offshore wind power pile foundation includes a pile foundation 1, fixed ice and floating ice exist near the sea level, and the pile foundation 1 is within the action range of the fixed ice and floating ice in the vertical direction. A fixedly connected shrinkable bladder 2 is provided around the pile foundation 1. The shrinkable bladder 2 is made of flexible material, and an inlet valve 3 is provided on the shrinkable bladder 2. According to the interaction between the fixed ice and floating ice and the pile foundation 1, a medium is filled into the shrinkable bladder 2 through the inlet valve 3 to change the shape and internal pressure of the shrinkable bladder 2, and the overall frequency characteristics of the shrinkable bladder 2 are changed to avoid ice-induced vibration.

[0028] like Figure 1 As shown in the figure, the above-mentioned shrinkable bladder 2 is annular, the inner side of the ring is fixedly connected to the outer side of the pile foundation 1, and the outer side of the ring is a deformation part, which is in contact with the external ice layer. When the medium is filled, the outer side of the shrinkable bladder 2 gradually changes from a contracted state to an expanded state, and its natural frequency is changed by the amount of the filled medium, thereby avoiding ice-induced vibration and causing resonance of the pile foundation.

[0029] like Figure 2 As shown in FIG, the above-mentioned shrinkable bladder 2 is also provided with a discharge valve 4 for discharging the medium to the outside.

[0030] The medium filled in the above-mentioned shrinkable capsule 2 is gas or liquid.

[0031] The preferred solution is Figure 3 and 4 In the above-mentioned shrinkable bladder 2, an axial partition 5 is provided along the axial direction of the pile foundation 1. The axial partition 5 is sealed and connected with the upper and lower layers of the shrinkable bladder 2 in the axial direction, and the shrinkable bladder 2 is divided into different chambers. Each chamber is respectively provided with an inlet valve 3 and an outlet valve 4. Different chambers can be selected to be filled with medium according to the impact of the drifting ice. When there is little drifting ice, only the outermost chamber can be filled with gas to achieve a buffering effect. When the drifting ice is more and thicker, each chamber is filled with medium. According to the impact frequency of the drifting ice or the fixed ice crushing frequency, the pressure of the medium is selected to increase or decrease the overall frequency, so that the impact frequency of the drifting ice and the overall frequency of the device are at completely different values ​​to avoid ice-induced vibration.

[0032] In a preferred embodiment, the above-mentioned axial partitions 5 are provided in plurality, dividing the internal space of the shrinkable bladder 2 into a plurality of different chambers. The outermost chamber of the shrinkable bladder 2 is a buffer chamber 6, and the buffer chamber 6 is filled with gas as the medium for buffering the action of flowing ice. The inner chamber is a pressurized chamber 7, and the pressurized chamber 7 is filled with liquid or gas as the medium for changing the overall frequency characteristics of the shrinkable bladder 2 with a medium of a specific pressure.

[0033] The preferred solution is Figure 5 and 6In the embodiment, a fixedly connected floating ice vibration sensor 8 is provided on the outer side of the pile foundation 1. The floating ice vibration sensor 8 is fixedly connected to the pile foundation 1 by a connecting rod structure. The floating ice vibration sensor 8 is located at the position of the ice layer in the vertical direction and is used to sense the impact frequency of the floating ice. A fixedly connected pile foundation vibration sensor 9 is provided on the inner side of the pile foundation 1 and is used to sense the swing frequency of the pile foundation 1. The floating ice vibration sensor 8 can sense the impact frequency of the ice layer from multiple directions, thereby controlling the filling medium of the capsule chamber.

[0034] The preferred solution is Figure 7 In the above-mentioned shrinkable bladder 2, four radial partitions 10 are provided on the radial plane along the pile foundation 1. The radial partitions 10 are sealed and connected with the upper and lower layers of the shrinkable bladder 2 in the axial direction, and the inside of the shrinkable bladder 2 is divided into four parts in the radial direction. The axial partitions 5 and the radial partitions 10 are combined to divide the shrinkable bladder 2 into different radial partitions and axial partitions, and each of the separated bladder chambers is provided with an inlet valve 3 and an outlet valve 4.

[0035] The preferred solution is Figure 8 In the embodiment, the buffer chamber 6 is filled with medium by a buffer pump 12, the pressurized chamber 7 is filled with medium by a pressurizing pump 13, the motor of the buffer pump 12 is regulated by a buffer pump driver 14, and the motor of the pressurizing pump 13 is regulated by a pressurizing pump driver 15.

[0036] like Figure 8 As shown in the figure, the buffer pump driver 14 and the charging pump driver 15 are electrically connected to the output end of the controller 11, and the output end of the controller 11 is also electrically connected to each inlet valve 3 and the outlet valve 4. The floating ice vibration sensor 8 and the pile foundation vibration sensor 9 are electrically connected to the input end of the controller 11. The controller 11 controls the buffer pump 12 and the charging pump 13 according to the received floating ice impact frequency and pile foundation vibration frequency, thereby adjusting each capsule chamber.

[0037] The working principle of this structure is: by detecting the impact frequency of external fixed ice breaking or flowing ice, each chamber in the shrinkable capsule 2 is filled with medium of different mass and pressure, thereby changing the natural frequency so that it is not in the same order of magnitude as the impact frequency, avoiding ice-induced vibration;

[0038] When there is no ice layer, the medium in the shrinkable bladder 2 can be discharged, and the shrinkable bladder 2 is closely attached to the periphery of the pile foundation 1, thereby reducing the cross-sectional area of ​​the pile foundation 1 and avoiding being affected by a larger ocean current;

[0039] When there is an impact of fixed ice or floating ice, the floating ice vibration sensor 8 arranged at the periphery detects the impact frequency in each direction, and the pile foundation vibration sensor 9 detects the actual vibration frequency of the pile foundation, thereby adjusting the medium filled into the chamber in each direction;

[0040] Through the multiple axially arranged capsule chambers, the outer buffer capsule chamber 6 is filled with gas at a certain pressure, so that the outer capsule chamber acts as a damper for the impact of floating ice, thereby reducing the impact of the internal capsule chamber and the pile foundation 1;

[0041] The above-mentioned controller adopts Siemens S7-1200 PLC, which has its own PID controller. It can automatically adjust the quantity and pressure of the filled medium by inputting the inherent characteristic parameters of the medium and the impact frequency of the peripheral detection, so as to achieve the purpose of intelligent control.

Claims

1. A flexible ice-resistant structure suitable for offshore wind power pile foundation, comprising a pile foundation, characterized in that: A fixedly connected shrinkable bladder is arranged around the pile foundation. The shrinkable bladder is made of flexible material and is provided with an inlet valve. According to the interaction between the fixed ice, the drifting ice and the pile foundation, the shrinkable bladder is filled with a medium through the inlet valve to change the shape and internal pressure of the shrinkable bladder. The overall frequency characteristics of the shrinkable bladder are changed to avoid ice-induced vibration. An axial partition is provided in the collapsible bladder along the axial direction of the pile foundation, and the axial partition is sealed and connected to the upper and lower layers of the collapsible bladder in the axial direction, dividing the collapsible bladder into different bladder chambers, each of which is provided with an inlet valve and an outlet valve, and the outlet valve is used to discharge the medium to the outside; The axial partitions are provided in plurality, dividing the inner space of the shrinkable capsule into a plurality of different capsule chambers. The outermost capsule chamber of the shrinkable capsule is a buffer capsule chamber, and the medium filled in the buffer capsule chamber is gas, which is used for buffering the action of drifting ice. The inner capsule chamber is a pressurized capsule chamber, and the medium filled in the pressurized capsule chamber is liquid or gas, which is used for changing the frequency characteristics of the shrinkable capsule as a whole by using a medium of a specific pressure. Four radial partitions 0 are arranged on the radial plane along the pile foundation inside the shrinkable bladder body. The radial partition 0 is sealed and connected with the upper and lower layers of the shrinkable bladder body in the axial direction, and the inside of the shrinkable bladder body is divided into four parts in the radial direction. The axial partition and the radial partition 0 are combined to divide the shrinkable bladder body into different radial partitions and axial partitions, and each of the separated bladder chambers is provided with an inlet valve and an outlet valve.

2. The flexible ice-resistant structure suitable for offshore wind power pile foundation according to claim 1 is characterized by: The shrinkable bladder is annular, the inner side of the annular ring is fixedly connected to the outer side of the pile foundation, and the outer side of the annular ring is a deformation part that contacts the external ice layer.

3. The flexible ice-resistant structure suitable for offshore wind power pile foundation according to claim 1, characterized in that: A fixedly connected floating ice vibration sensor is provided on the outside of the pile foundation. The floating ice vibration sensor is fixedly connected to the pile foundation by a connecting rod structure. The floating ice vibration sensor is located at the position of the ice layer in the vertical direction and is used to sense the impact frequency of the floating ice. A fixedly connected pile foundation vibration sensor is provided on the inside of the pile foundation and is used to sense the swing frequency of the pile foundation.

4. The flexible ice-resistant structure suitable for offshore wind power pile foundation according to claim 3 is characterized by: The buffer chamber is filled with medium by a buffer pump, the pressure chamber is filled with medium by a pressure pump, the buffer pump motor is regulated by a buffer pump driver, and the pressure pump motor is regulated by a pressure pump driver.

5. The flexible ice-resistant structure suitable for offshore wind power pile foundation according to claim 4 is characterized by: The buffer pump driver and the charging pump driver are electrically connected to the output end of the controller, and the output end of the controller is also electrically connected to each inlet valve and the outlet valve. The floating ice vibration sensor and the pile foundation vibration sensor are electrically connected to the input end of the controller. The controller controls the buffer pump and the charging pump according to the received floating ice impact frequency and pile foundation vibration frequency, thereby adjusting each capsule chamber.

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