An anti-freezing device and method for a wind turbine blade

Abstract

The present invention discloses an anti-freezing device and method for a wind turbine blade, comprising a wind power generation system and a lifting and shielding system; the wind power generation system is used for converting wind energy into electric energy; the lifting and shielding system is arranged on the blade of the wind power generation system and is used for shielding rain and snow; the lifting and shielding system includes upper and lower fixing rings, slideway grooves, rollers, shielding cloth, a DC motor and a lifting rope; the upper and lower fixing rings include an upper fixing ring and a lower fixing ring; the upper fixing ring and the lower fixing ring are respectively arranged at the upper and lower ends of the blade; a slideway groove is arranged between the upper fixing ring and the lower fixing ring, and rollers are arranged inside the slideway groove, and the rollers are slidably connected with the slideway groove; the rollers are connected with the shielding cloth; the shielding cloth is stacked together at the upper end of the lower fixing ring in the initial state; a DC motor is arranged at the upper fixing ring, the output shaft of the motor is connected with the lifting rope, and the lifting rope is buckled with the rollers. It ensures that the wind turbine generator set is not affected by bad weather and improves the blade life.

Description

Technical Field

[0001] The invention belongs to the application field of new energy wind power generation, and in particular to a wind turbine blade antifreeze device and method. Background Art

[0002] As countries around the world pay more and more attention to energy security, ecological environment, climate change and other issues, accelerating the development of the wind power industry has become a general consensus and concerted action of the international community to promote energy transformation and development and respond to global climate change. By the end of 2020, my country's wind power installed capacity reached more than 200GW, ranking first in the world since 2008, accounting for 32.24% of the world's cumulative wind power installed capacity.

[0003] Wind energy is particularly abundant in plateaus, cold areas, ridges, and mountain tops, and has great development value. However, these places are at high altitudes, with high humidity and low temperatures. People may think that it is rotating most of the time, and it is not easy for rain, ice and snow to cover it. In fact, when our wind turbines are running at low temperatures of zero degrees Celsius or below zero, once they encounter humid air, salt spray, rain, ice and snow, or even supercooled water droplets, the blades will freeze and ice will form, and then the ice layer will gradually grow and thicken. The aerodynamic performance of the blades is affected by icing. On the one hand, it will cause blade overload and uneven distribution of blade load, which will in turn cause a greater impact on the continuous output of wind energy. On the other hand, when the blades are rotating, it is very easy to cause operational accidents caused by ice falling off. For wind turbine blades, ice on the blades will cause us great harm.

[0004] At present, wind turbine blade deicing is mainly done by coating deicing, which is achieved by weakening the bonding force between the ice and the coating surface. However, studies have found that hydrophobicity is only one of the determinants of the currently foreseeable anti-icing properties, and this coating is not necessarily an anti-icing coating. The strong hydrophobicity of the coating does not mean that the coating surface is not prone to ice and frost. At present, the water contact angle test is mostly used in China to characterize the performance of anti-icing coatings. This method has limitations. The icing situation of blades in real environments is complex, and the water contact angle alone cannot fully evaluate the anti-icing performance of blade coatings. Summary of the invention

[0005] In order to solve the problems existing in the prior art, the present invention provides a wind turbine blade antifreeze device and method, which can protect the wind turbine blades from extreme weather (snow, dust) in real time, comprehensively and permanently. The present invention has the characteristics of remote control (no manual work), convenience and speed, adequate protection, reusability and cost saving, and provides a more efficient and practical solution to wind turbine blade snow accumulation.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] An anti-freezing device for a wind turbine blade, comprising a wind power generation system and a lifting and shielding system;

[0008] The wind power generation system is used to convert wind energy into electrical energy; the lifting and shielding system is arranged on the blade of the wind power generation system and is used to shield rain and snow;

[0009] The lifting and shielding system includes upper and lower fixing rings, slide channels, rollers, shielding cloth, a DC motor and a lifting rope; the upper and lower fixing rings include an upper fixing ring and a lower fixing ring; the upper fixing ring and the lower fixing ring are respectively arranged at the upper and lower ends of the blade;

[0010] A slide channel is arranged between the upper fixing ring and the lower fixing ring, and rollers are arranged inside the slide channel. The rollers are slidably connected to the slide channel;

[0011] The rollers are connected to the shielding cloth; the shielding cloth is stacked together at the upper end of the lower fixing ring in the initial state; a DC motor is arranged at the upper fixing ring, the output shaft of the motor is connected to the lifting rope, and the lifting rope is connected to the rollers through a buckle.

[0012] Preferably, it further includes an energy storage and power supply system, which is used to store the electrical energy of the wind turbine generator set and supply electrical energy to the lifting and shielding system.

[0013] Preferably, the wind power generation system includes blades, a hub, a nacelle, a tower barrel, a foundation and cables;

[0014] A gearbox, a first rotating shaft, a second rotating shaft and a generator are arranged inside the nacelle;

[0015] Both ends of the first rotating shaft are connected to the hub and the gearbox, the output end of the gearbox is connected to the second rotating shaft, and the second rotating shaft is connected to the generator; when the wind drives the blades and the hub to rotate, it drives the low-speed rotation, the gearbox and the second rotating shaft to rotate, driving the generator to rotate and generate electricity, and the generated electricity is transmitted to the grid side for power generation through the cables; the tower barrel and the foundation are used to support and fix the main structure of the generator for power generation.

[0016] Furthermore, the electric energy storage system includes an energy storage battery, a relay and an inverter;

[0017] The energy storage battery is arranged on the foundation inside the tower barrel, the relay is connected to the output line of the generator, and the inverter is connected between the relay and the energy storage battery to convert the alternating current generated by the generator into direct current.

[0018] Preferably, the upper fixing ring is welded to the tip of the blade, and the lower fixing ring is welded to the bottom of the blade.

[0019] Preferably, heating wires are arranged inside the lower fixing ring.

[0020] Preferably, it further includes a stop switch, and the stop switch is arranged in the slideway groove; the stop switch is an electric control spring stop switch, and the stop switch includes a return spring and a triangular metal sheet. The return spring passes through the side wall of the slideway groove, and the triangular metal sheet is fixed at the end of the return spring for stopping.

[0021] Preferably, the shielding cloth is made of ultra-strength nylon cloth.

[0022] A method for preventing freezing of wind turbine blades, based on the wind turbine blade anti-freezing device described in any one of the above, includes the following processes

[0023] In the initial stage, the shielding cloth is stacked on the upper end of the lower fixing ring; the energy storage and power supply system is charged.

[0024] In the working stage of the lifting and shielding system, the DC motor rotates to drive the lifting rope to lift, and the linkage roller and the shielding cloth move to the top and stop together to protect the blade.

[0025] When the working stage of the lifting and shielding system is completed, the DC motor rotates to drive the lifting rope to descend, and the linkage roller and the shielding cloth move to the bottom and stop together.

[0026] Preferably, when the working stage of the lifting and shielding system is completed, the energy storage battery provides electric energy to the heating wire, and the heating wire becomes hot to melt the ice and snow covering the shielding cloth.

[0027] Compared with the prior art, the present invention has the following beneficial technical effects:

[0028] The present invention realizes a method for quickly and efficiently protecting wind turbine blades, ensures that the wind turbine generator set is not affected by bad weather, improves the blade life, increases the power generation amount in the whole life cycle, and has good economy. This device can be used repeatedly, reducing the cost of purchasing protective equipment and reducing expenses. It eliminates the need for manual on-site de-icing maintenance and reduces the operation and maintenance cost.

[0029] The present invention discloses a wind turbine blade anti-freezing device, which includes a wind power generation system, a lifting and shielding system, and an energy storage and power supply system. Among them, the wind power generation system is used to convert wind energy into electric energy for grid connection or provide electric energy for the energy storage and power supply system of the present invention device; the lifting and shielding system is installed on the blade of the wind power generation system and is used to lift the protective device to shield the blade from the invasion of rain and snow. The energy storage and power supply system stores the redundant electric energy generated by the wind turbine generator set that cannot be consumed and provides electric energy for the lifting and shielding system according to the control instruction. The present invention has the characteristics of remote control, convenience, quickness, in-place protection, and cost saving by repeated use, and provides a more efficient and practical solution for the snow accumulation on the blades of wind turbine generator sets in wind farms. Description of the Drawings

[0030] Figure 1 This is a schematic diagram of the overall structure of an anti-freezing device for the blades of a wind turbine according to the present invention.

[0031] Figure 2 This is a schematic diagram of the lifting and shielding system structure according to the present invention.

[0032] Figure 3 This is a schematic diagram of the limit switch structure according to the present invention.

[0033] In the drawings: 1 is a wind power generation system, 2 is a lifting and shielding system, 3 is an energy storage and power supply system, 1-1 is a blade, 1-2 is a hub, 1-3 is a nacelle, 1-4 is a tower barrel, 1-5 is a foundation, 1-6 is a cable, 1-7 is a gearbox, 1-8-1 is a first rotating shaft, 1-8-2 is a second rotating shaft, 1-9 is a generator, 2-1 is a fixing ring, 2-1-1 is an upper fixing ring, 2-1-2 is a lower fixing ring, 2-2 is a slideway groove, 2-3 is a roller, 2-4 is a shielding cloth, 2-5 is a motor, 2-6 is a lifting rope, 2-7 is a heating wire, 2-8 is a limit switch, 3-1 is an energy storage battery, 3-2 is a relay, 3-3 is an inverter. Detailed implementation manners

[0034] The following further elaborates on the present invention in detail in conjunction with specific embodiments, which are explanations of the present invention rather than limitations.

[0035] Embodiment

[0036] Referring to the attached Figure 1 , the present invention designs an anti-freezing device for the blades of a wind turbine, including a wind power generation system 1, a lifting and shielding system 2, and an energy storage and power supply system 3. Among them, the wind power generation system 1 is used to convert wind energy into electrical energy for grid connection or provide electrical energy for the energy storage and power supply system 3 of the present invention device; the lifting and shielding system 2 is installed on the blades of the wind power generation system 1 and is used to lift the protection device to shield the blades from the invasion of rain and snow. The energy storage and power supply system 3 stores the excess electrical energy generated by the wind turbine that cannot be consumed and provides electrical energy for the lifting and shielding system 2 according to the control instruction.

[0037] Specifically, the wind power generation system 1 includes blades 1-1, hub 1-2, nacelle 1-3, tower 1-4, foundation 1-5 and cable 1-6. The nacelle 1-3 contains a gearbox 1-7, a first rotating shaft 1-8-1, a second rotating shaft 1-8-2 and a generator 1-9. The first rotating shaft 1-8-1 is a low-speed rotating shaft, and the second rotating shaft 1-8-2 is a high-speed rotating shaft; the two ends of the first rotating shaft 1-8-1 are connected to the hub 1-2 and the gearbox 1-7, the output end of the gearbox 1-7 is connected to the second rotating shaft 1-8-2, and the second rotating shaft 1-8-2 is connected to the generator 1-9. When the wind blows through the blades and drives the blades 1-1 and the hub 1-2 to rotate, the low-speed shaft 1-8-1, the gearbox 1-7, and the second rotating shaft 1-8-2 are driven to rotate, and finally the generator 1-9 is driven to rotate and generate electricity, and the generated electricity is transmitted to the grid side through the cable 1-6 for power generation. The tower 1-4 and the foundation 1-5 are used to support and fix the main structure of the generator.

[0038] Refer to the attached Figure 2 The lifting and shielding system 2 includes four parts: an upper and lower fixed ring 2-1, a slide groove 2-2, a roller 2-3, and a shielding cloth 2-4. The upper and lower fixed rings 2-1 are respectively installed at the upper and lower ends of the blade 1-1 by welding. The upper fixed ring 2-1-1 is welded and connected to the top of the blade, and the lower fixed ring 2-1-2 is welded and connected to the bottom of the blade. The upper and lower fixed rings are connected by setting two slide grooves 2-2 symmetrically at 180 degrees, and the roller 2-3 slides in the slide groove 2-2. The roller 2-3 is bonded to the shielding cloth 2-4. The shielding cloth 2-4 is initially overlapped at the upper end of the lower fixed ring 2-1-2. Two DC motors 2-5 are installed at the top of the two slide grooves symmetrically at 180 degrees at the upper fixed ring 2-1-1. The output shaft of the motor 2-5 is connected to the lifting rope 2-6, and the lifting rope 2-6 is connected to the roller 2-3 through a buckle. A heating wire 2-7 is arranged inside the lower fixing ring 2-1-2, and the shielding cloth 2-4 is a super-strength nylon cloth.

[0039] Refer to the attached Figure 3 An electrically controlled spring stop switch 2-8 is arranged in the slideway groove 2-2 near the lower fixing ring 2-1-2. The stop switch 2-8 is arranged in the slideway groove 2-2. The stop switch 2-8 is an electrically controlled spring stop switch. The stop switch 2-8 includes a return spring and a triangular metal sheet. The return spring passes through the side wall of the slideway groove 2-2. The triangular metal sheet is fixed to the end of the return spring for stopping. As can be seen from its structural characteristics, its function is that the roller 2-3 can move from the tip of the blade from top to bottom through this switch, but when power is not supplied, it cannot move freely from the lower end of the blade to the upper end, so as to prevent the shielding cloth 2-4 of the lifting shielding system 2 from falling off when the tip of the blade rushes down during the rotation of the blade. When it is powered on, the roller 2-3 can be pulled up from the bottom of the blade and passed through.

[0040] Refer to the attached Figure 1, the electric energy storage system 3 consists of an energy storage battery 3-1, a relay 3-2 and an inverter 3-3. The energy storage battery 3-1 is installed on the internal foundation 1-5 of the tower barrel 1-4. The relay 3-2 is connected to the output line of the generator 1-9, and an additional power line to the energy storage battery 3-1 is added. By controlling the working switching state of the relay 3-2 through the background, the current transmission line can be switched at any time to charge the energy storage battery 3-1. The inverter 3-3 is connected between the relay 3-2 and the energy storage battery 3-1, converting the alternating current generated by the generator 1-9 into direct current that the energy storage battery 3-1 can accept. The output of the energy storage battery 3-1 is respectively connected to two DC motors 2-5 and a heating wire 2-7, providing kinetic energy for the DC motors 2-5 and heat for the heating wire 2-7.

[0041] A method for preventing the blades of a wind turbine from freezing according to the present invention has the following specific process:

[0042] Before the lifting and shielding system works: In the initial stage, the shields 2-4 are stacked on the upper end of the lower fixing ring 2-1-2. The rollers 2-3 are bonded to the shielding cloth 2-4 and also connected to the lifting rope 2-6 through a buckle. When there is excess electricity that cannot be consumed, the remote control console sends a signal to the relay 3-2 to switch the electricity generated by the generator 1-9 to charge the energy storage battery 3-1.

[0043] During the working stage of the lifting and shielding system: When wind and snow come, the remote control console gives an instruction to the energy storage battery 3-1 to make it output electrical energy to make the DC motor 2-5 rotate forward. When the three blades reach the uppermost positions respectively, the energy storage battery 3-1 supplies power to the limit switch 2-8. The forward rotation of the DC motor 2-5 drives the lifting rope 2-6 to lift, then the linked rollers 2-3 and the shielding cloth 2-4 move to the highest position together. After that, the energy storage battery 3-1 stops supplying power. At this time, the lifting and shielding system 2 is lifted, which can play a role in protecting the blades in extreme weather such as wind and snow.

[0044] After the working stage of the lifting and shielding system: When the wind and snow pass, the remote control console gives a reverse instruction to the energy storage battery 3-1 to make it output electrical energy to make the DC motor 2-5 rotate in reverse. The reverse rotation of the two DC motors 2-5 drives the lifting rope 2-6 to descend, and the linked rollers 2-3 and the shielding cloth 2-4 move to the lowest position, that is, the power supply stops at the upper end of the lower fixing ring 2-1-2. At this time, the lowering of the lifting and shielding system 2 is completed, and then the wind turbine can work normally. The remote control console then gives an instruction to the energy storage battery 3-1 to make it supply electrical energy to the heating wire 2-7 to make the heating wire 2-7 heat up. Its function is to de-ice and melt the rain and snow covering the shielding cloth 2-4, so that the whole system can be reused.

Claims

1. An anti-freezing device for a wind turbine blade, characterized in that, It includes a wind power generation system (1) and a lifting and shielding system (2); The wind power generation system (1) is used to convert wind energy into electrical energy; the lifting and shielding system (2) is arranged on the blade (1-1) of the wind power generation system (1) for shielding rain and snow; The lifting and shielding system (2) includes upper and lower fixing rings (2-1), a slideway groove (2-2), rollers (2-3), a shielding cloth (2-4), a DC motor (2-5) and a lifting rope (2-6); the upper and lower fixing rings (2-1) include an upper fixing ring (2-1-1) and a lower fixing ring (2-1-2); the upper fixing ring (2-1-1) and the lower fixing ring (2-1-2) are respectively arranged at the upper and lower ends of the blade (1-1); A slideway groove (2-2) is arranged between the upper fixing ring (2-1-1) and the lower fixing ring (2-1-2), rollers (2-3) are arranged inside the slideway groove (2-2), and the rollers (2-3) are slidably connected with the slideway groove (2-2); The rollers (2-3) are connected to the shielding cloth (2-4); the shielding cloth (2-4) is stacked together at the upper end of the lower fixing ring (2-1-2) in the initial state; a DC motor (2-5) is arranged at the upper fixing ring (2-1-1), the output shaft of the motor (2-5) is connected to the lifting rope (2-6), and the lifting rope (2-6) is connected to the rollers (2-3) through a buckle; The upper fixing ring (2-1-1) is welded to the tip of the blade, and the lower fixing ring (2-1-2) is welded to the bottom of the blade; It also includes a limit switch (2-8), and the limit switch (2-8) is arranged in the slideway groove (2-2); the limit switch (2-8) is an electrically controlled spring limit switch, and the limit switch (2-8) includes a return spring and a triangular metal sheet. The return spring passes through the side wall of the slideway groove (2-2), and the triangular metal sheet is fixed at the end of the return spring for stopping.

2. The anti-freezing device for a wind turbine blade according to claim 1, wherein, It also includes an energy storage and power supply system (3), and the energy storage and power supply system (3) is used to store the electrical energy of the wind turbine generator set and supply electrical energy to the lifting and shielding system (2).

3. The anti-freezing device for a wind turbine blade according to claim 1, wherein, The wind power generation system (1) includes a blade (1-1), a hub (1-2), a nacelle (1-3), a tower barrel (1-4), a foundation (1-5) and a cable (1-6); A gearbox (1-7), a first rotating shaft (1-8-1), a second rotating shaft (1-8-2) and a generator (1-9) are arranged inside the nacelle (1-3); The two ends of the first rotating shaft (1-8-1) are connected to the hub (1-2) and the gear box (1-7); the output end of the gear box (1-7) is connected to the second rotating shaft (1-8-2); and the second rotating shaft (1-8-2) is connected to the generator (1-9); when the wind drives the blades (1-1) and the hub (1-2) to rotate, the first rotating shaft (1-8-1), the gear box (1-7) and the second rotating shaft (1-8-2) are driven to rotate, driving the generator (1-9) to rotate and generate electricity, and the generated electricity is transmitted to the power grid side through the cable (1-6) for power generation; the tower (1-4) and the foundation (1-5) are used to support and fix the main structure of the generator.

4. The anti-freezing device for a wind turbine blade according to claim 2, wherein, The energy storage and supply system (3) comprises an energy storage battery (3-1), a relay (3-2) and an inverter (3-3); The energy storage battery (3-1) is arranged on a foundation (1-5) inside the tower (1-4), the relay (3-2) is connected to an output line of the generator (1-9), and the inverter (3-3) is connected between the relay (3-2) and the energy storage battery (3-1) to convert the alternating current generated by the generator (1-9) into direct current.

5. The anti-freezing device for a wind turbine blade according to claim 1, wherein A heating wire (2-7) is provided inside the lower fixing ring (2-1-2).

6. The anti-freezing device for a wind turbine blade according to claim 1, characterized in that, The shielding cloth (2-4) is made of super-strength nylon cloth.

7. A method for preventing freezing of a wind turbine blade, characterized in that, A wind turbine blade antifreeze device according to any one of claims 1 to 6, comprising the following process: In the initial stage, the shielding cloth (2-4) is stacked on the upper end of the lower fixing ring (2-1-2); the energy storage and supply system (3) is charged; When the lifting and shielding system is in the working stage, the DC motor (2-5) rotates to drive the lifting rope (2-6) to lift, and the linkage roller (2-3) and the shielding cloth (2-4) move together to the top end and stop, thereby protecting the blade (1-1); When the working phase of the lifting and shielding system is completed, the DC motor (2-5) rotates to drive the lifting rope (2-6) to descend, and the linkage roller (2-3) and the shielding cloth (2-4) move together to the bottom and stop.

8. A method for preventing freezing of a wind turbine blade according to claim 7, characterized in that, When the working phase of the lifting and shielding system is completed, the energy storage battery (3-1) provides electric energy to the heating wire (2-7), and the heating wire (2-7) becomes hot, thereby deicing and melting the rain and snow covering the shielding cloth (2-4).

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