Ice removal system for wind turbine blades based on low-resistance metal materials, ice removal control method for blades, blades and wind turbine generators

Abstract

The present application discloses a de-icing system for a wind turbine blade based on a low-resistance metal material, a de-icing control method for the blade, the blade, and a wind power generation set. The de-icing system for the wind turbine blade includes a low-resistance metal heating component, which includes a low-resistance metal mesh heating layer. The low-resistance metal mesh heating layer includes a first low-resistance metal mesh, a second low-resistance metal mesh, a third low-resistance metal mesh, and a fourth low-resistance metal mesh that are arranged at intervals; an isolated DC power supply, which is used to provide direct current for the low-resistance metal heating component; the output positive pole of the isolated DC power supply, the first, second, third, and fourth low-resistance metal meshes, and the output negative pole of the isolated DC power supply are sequentially connected to form a closed-loop current circuit, and the output grounding end of the isolated DC power supply is connected to the connection between the second low-resistance metal mesh and the third low-resistance metal mesh and then connected to the downlead of the fan blade. The present application has good ice melting effect and lightning protection ability, simple installation process, and minimizes the impact on the mechanical strength and aerodynamic performance of the blade.

Description

Technical Field

[0001] The present application relates to the technical field of wind turbine generators, and particularly to an ice removal system for wind turbine blades based on low-resistance metal materials, an ice removal control method for blades, blades, and wind turbine generators. Background Art

[0002] As one of the important power generation methods that is safe, reliable, pollution-free, and can be connected to the grid, wind power generation has developed rapidly in recent years. In cold and humid regions, the blades of wind turbines are prone to icing, which in turn impairs the aerodynamic performance of the blades, reduces the power generation efficiency of the unit, causes the unit to accelerate fatigue, shortens the service life, and in severe cases, may cause the wind turbine to be forced to shut down or even collapse, endangering personal safety. Therefore, the problem of icing on wind turbine blades has received increasing attention, and ice removal systems for wind turbine blades have also developed rapidly.

[0003] The existing anti-icing / de-icing technologies for wind turbine generator blades mainly focus on research related to electric heating de-icing, hot gas de-icing, and special coating methods. Compared with the electric heating method, the application effects of hot gas de-icing and special coating protection technologies are not good. The electric heating technology eliminates the icing problem on the blade by arranging a heating layer on the blade surface or inner layer. After the heating layer is energized, Joule heat is generated to increase the blade surface temperature, thereby increasing the operating time of the wind turbine generator. However, when using the electric heating method for anti-icing and de-icing on the blade, the electric heating device will increase the risk of attracting lightning during thunderstorm weather, and the lightning strike current will damage the heating element or even damage the blade.

[0004] In the existing electric heating de-icing systems, the heating elements used mainly include silicone rubber composite heating elements with alloy resistance wires as the core, carbon fiber cloth heating elements, carbon crystal heating films, graphene heating films, etc. Such heating elements have large equivalent resistances, low current-carrying capacities, and poor lightning strike current resistance capabilities, and the risk of lightning strike damage to the heating elements is relatively high. In addition, during the installation process of the existing ice melting heating elements, multiple layers need to be laid, which greatly modifies the blade surface, has a complex installation process, and a poor ice melting effect.

[0005] Currently, there are mainly two types of lightning protection research for electric heating de-icing systems. One is to increase the metal shielding layer structure. For example, the patent (application number 201721165207.X) proposes an electric heating de-icing device for wind turbine rotor blades, which belongs to the traditional high-resistance material electric heating method and requires an additional metal mesh shielding cover for lightning protection, with a complex installation process. In addition, the thickness of the high-impedance composite heating element generally exceeds 3 mm and needs to be embedded under the surface of the wind turbine blade, resulting in problems such as a complex installation process and easy influence on the mechanical strength of the blade.

[0006] Therefore, how to simplify the installation process of the electric heating de-icing system while ensuring the de-icing effect and lightning protection ability, and minimize the impact on the mechanical strength and aerodynamic performance of the blade is a technical problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0007] To solve the above technical problems, the present application provides a wind turbine blade de-icing system based on a low-resistance metal material, which can simplify the installation process of the electric heating de-icing system while ensuring the de-icing effect and lightning protection ability, and minimize the impact on the mechanical strength and aerodynamic performance of the blade. The present application also provides a blade de-icing control method, a blade and a wind turbine generator set, which have the same technical effects.

[0008] The first object of the present application is to provide a wind turbine blade de-icing system based on a low-resistance metal material.

[0009] The above object one of the present application is achieved by the following technical solutions:

[0010] A wind turbine blade de-icing system based on a low-resistance metal material, comprising:

[0011] A low-resistance metal heating component, which is laid on the outer surface of the wind turbine blade, and the low-resistance metal heating component includes a low-resistance metal mesh heating layer, and the low-resistance metal mesh heating layer includes a first low-resistance metal mesh, a second low-resistance metal mesh, a third low-resistance metal mesh and a fourth low-resistance metal mesh which are arranged at intervals; and

[0012] An isolated DC power supply, which is used to provide direct current for the low-resistance metal heating component;

[0013] Wherein,

[0014] The output positive electrode of the isolated DC power supply, the first low-resistance metal mesh, the second low-resistance metal mesh, the third low-resistance metal mesh, the fourth low-resistance metal mesh, and the output negative electrode of the isolated DC power supply are connected in sequence to form a closed-loop current circuit, and the output grounding end of the isolated DC power supply is connected to the connection between the second low-resistance metal mesh and the third low-resistance metal mesh and then connected to the blade downlead of the fan.

[0015] Preferably, a first control switch is arranged between the output positive electrode of the isolated DC power supply and the connection between the second low-resistance metal mesh and the third low-resistance metal mesh, and a second control switch is arranged between the output negative electrode of the isolated DC power supply and the connection between the second low-resistance metal mesh and the third low-resistance metal mesh.

[0016] Preferably, the low-resistance metal mesh heating layer further includes a positive connection row, a grounding terminal connection row, a negative connection row, a positive short-circuit row, and a negative short-circuit row, and the positive connection row, the grounding terminal connection row, the negative connection row, the positive short-circuit row, and the negative short-circuit row are all made of low-resistance metal materials;

[0017] The output positive pole of the isolated DC power supply is connected to the first low-resistance metal mesh through the positive connection row, the first low-resistance metal mesh and the second low-resistance metal mesh are connected through the positive short-circuit row, the second low-resistance metal mesh, the third low-resistance metal mesh and the output grounding terminal of the isolated DC power supply are connected through the grounding terminal connection row, the third low-resistance metal mesh and the fourth low-resistance metal mesh are connected through the negative short-circuit row, and the fourth low-resistance metal mesh and the output negative pole of the isolated DC power supply are connected through the negative connection row.

[0018] Preferably, the low-resistance metal heating assembly further includes a grid-shaped top fiberglass cloth and a grid-shaped bottom fiberglass cloth, the low-resistance metal mesh heating layer is sandwiched between the grid-shaped top fiberglass cloth and the grid-shaped bottom fiberglass cloth, and the grid-shaped top fiberglass cloth and the grid-shaped bottom fiberglass cloth are both connected by high thermal conductivity composite adhesives.

[0019] Preferably, the low-resistance metal heating assembly is adhesively bonded to the leading edge of the fan blade by a high thermal conductivity composite adhesive.

[0020] Preferably,

[0021] One low-resistance metal heating assembly is provided, the first low-resistance metal mesh, the second low-resistance metal mesh, the third low-resistance metal mesh and the fourth low-resistance metal mesh are evenly spaced along the thickness direction of the wind turbine blade, and each low-resistance metal mesh extends along the length direction of the wind turbine blade; or

[0022] A plurality of low-resistance metal heating assemblies are provided, the plurality of low-resistance metal heating assemblies are spaced along the length direction of the wind turbine blade, and the first low-resistance metal mesh, the second low-resistance metal mesh, the third low-resistance metal mesh and the fourth low-resistance metal mesh of each low-resistance metal heating assembly are evenly spaced along the thickness direction of the wind turbine blade.

[0023] Preferably,

[0024] Each low-resistance metal mesh is a mesh structure formed by the intersection of a plurality of transverse low-resistance metal wires made of low-resistance metal materials and a plurality of longitudinal low-resistance metal wires made of low-resistance metal materials, and the intersections of the transverse low-resistance metal wires and the longitudinal low-resistance metal wires are connected by a die-casting connection process; or

[0025] Each low-resistance metal mesh is a mesh-shaped low-resistance metal foil uniformly distributed with a plurality of through holes, and the mesh-shaped low-resistance metal foil is made of a low-resistance metal foil by a die-casting punching process.

[0026] The second object of the present application is to provide a method for controlling blade de-icing.

[0027] The above-mentioned second application object of the present application is achieved by the following technical solutions:

[0028] A method for controlling blade de-icing, which is applied to the wind turbine blade de-icing system based on low-resistance metal materials described in any one of the above-mentioned first objects, and the method for controlling blade de-icing includes:

[0029] Obtain the real-time temperature value of the low-resistance metal mesh;

[0030] Compare the real-time temperature value with a preset temperature reference value, and adjust the heating power of the low-resistance metal mesh according to the comparison result;

[0031] Calculate the heating power integral filtering value of the low-resistance metal mesh according to the output voltage and output current of the isolated DC power supply;

[0032] Detect the ambient temperature value around the wind turbine blade;

[0033] Calculate the thermal resistance value between the low-resistance metal mesh and the air according to the heating power integral filtering value, the ambient temperature value and the temperature reference value;

[0034] Compare the thermal resistance value with a preset thermal resistance setting value, and adjust the temperature reference value according to the comparison result.

[0035] The third object of the present application is to provide a blade.

[0036] The above-mentioned third application object of the present application is achieved by the following technical solutions:

[0037] A blade, on which is provided the wind turbine blade de-icing system based on low-resistance metal materials described in any one of the above-mentioned first objects.

[0038] The fourth object of the present application is to provide a wind power generation set.

[0039] The above-mentioned fourth application object of the present application is achieved by the following technical solutions:

[0040] A wind power generation set, which includes the blade described in the above-mentioned third object.

[0041] In the above technical solution, the output grounding ends of each low-resistance metal mesh and the isolated DC power supply are effectively connected to the ground by connecting with the down-lead of the fan blade, and the low-resistance metal mesh is equivalent to the down-lead of the blade, with extremely high lightning current impact resistance. Coupled with the fact that the isolated DC power supply can effectively isolate its input and output, when lightning strikes, the lightning can be effectively discharged to the ground through the down-lead of the fan blade, thus achieving good lightning safety protection and effectively avoiding the impact of lightning overvoltage on the electrical control system of the wind turbine blade de-icing system. There is no need to additionally increase the lightning protection shielding layer, thus minimizing the impact on the mechanical strength and aerodynamic performance of the blade; since the low-resistance metal mesh of the low-resistance metal heating component is laid on the outer surface of the wind turbine blade, the low-resistance metal heating component can be pasted and constructed by using a high thermal conductivity composite adhesive in a hand-laying bonding method, and the installation process is simple; using the low-resistance metal material to prepare the low-resistance metal mesh heating layer to heat and de-ice the wind turbine blade can effectively improve the overall thermal efficiency and ice melting performance of the wind turbine blade heating and de-icing, and better meet the de-icing and anti-icing capabilities of the wind power generation unit under low-temperature weather conditions. In summary, the above technical solution can ensure the ice melting effect and lightning protection ability while simplifying the installation process of the electric heating de-icing system and minimizing the impact on the mechanical strength and aerodynamic performance of the blade. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0043] Figure 1 It is a schematic structural diagram of a wind turbine blade de-icing system based on low-resistance metal materials in an embodiment of the present application;

[0044] Figure 2 It is a control principle block diagram of a wind turbine blade de-icing system based on low-resistance metal materials in an embodiment of the present application;

[0045] Figure 3 It is a schematic cross-sectional structure diagram of a low-resistance metal heating component in an embodiment of the present application;

[0046] Figure 4 It is a schematic structural diagram of a low-resistance metal mesh in an embodiment of the present application;

[0047] Figure 5 It is another schematic structural diagram of a low-resistance metal mesh in an embodiment of the present application;

[0048] Figure 6 It is a schematic structural diagram of a blade in an embodiment of the present application;

[0049] Figure 7 This is the temperature-resistivity curve graph of copper and aluminum in the embodiments of the present application;

[0050] Figure 8 This is the method flow chart of the blade de-icing control method in the embodiments of the present application. Detailed implementation manners

[0051] In order to enable those skilled in the art to better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0052] In the embodiments provided by the present application, it should be understood that the disclosed methods and systems can be implemented in other ways. The system embodiments described below are only illustrative. For example, the division of units and modules is only a logical function division. In actual implementation, there may be other division methods, such as: multiple units or modules can be combined, or can be integrated into another system, or some features can be ignored, or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed with each other can be through some interfaces, and the indirect coupling or communication connection of devices or modules can be electrical, mechanical, or other forms.

[0053] In addition, each functional unit in the embodiments of the present application can be all integrated in one processor, or each unit can be separately used as a device, or two or more units can be integrated in one device; each functional unit in the embodiments of the present application can be implemented in the form of hardware, or in the form of a combination of hardware and software functional units.

[0054] Those of ordinary skill in the art can understand that all or part of the steps of implementing the following method embodiments can be completed through program instructions and related hardware. The foregoing program instructions can be stored in a computer-readable storage medium. When the program instructions are executed, the steps of the following method embodiments are executed; and the foregoing storage medium includes: various media that can store program codes, such as removable storage devices, read-only memory (ROM), magnetic disks, or optical discs.

[0055] In addition, the terms "first" and "second" are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of this application, "a plurality of" or "several" means two or more, unless otherwise specifically defined.

[0056] The embodiments of this application are written in a progressive manner.

[0057] As Figure 1-6 shown, the embodiments of this application provide an ice removal system for wind turbine blades based on a low-resistance metal material, including a low-resistance metal heating component 1 and an isolated DC power supply 2; the low-resistance metal heating component 1 is laid on the outer surface of the wind turbine blade, and the low-resistance metal heating component 1 includes a low-resistance metal mesh heating layer 11, and the low-resistance metal mesh heating layer 11 includes a first low-resistance metal mesh 111, a second low-resistance metal mesh 112, a third low-resistance metal mesh 113, and a fourth low-resistance metal mesh 114 which are arranged at intervals; the isolated DC power supply 2 is used to convert the alternating current input at its input end into direct current with low voltage and large current to provide a working power supply for the low-resistance metal heating component 1; the positive output of the isolated DC power supply 2, the first low-resistance metal mesh 111, the second low-resistance metal mesh 112, the third low-resistance metal mesh 113, the fourth low-resistance metal mesh 114, and the negative output of the isolated DC power supply 2 are connected in sequence to form a closed-loop current circuit, and the grounded end of the output of the isolated DC power supply 2 is connected to the connection point of the second low-resistance metal mesh 112 and the third low-resistance metal mesh 113 and then connected to the downlead of the wind turbine blade.

[0058] It should be noted that the above-mentioned low-resistance metal material refers to a metal material with low resistivity. For example, metal materials such as silver, copper, gold, and aluminum. Since the metal material with low resistivity has strong current-carrying capacity, the heating performance and lightning protection ability of the ice removal system for wind turbine blades can be effectively improved.

[0059] Specifically, in this embodiment, the first low-resistance metal mesh 111, the second low-resistance metal mesh 112, the third low-resistance metal mesh 113, and the fourth low-resistance metal mesh 114 are made of copper or aluminum, which are low-resistivity metal materials with low cost and easy availability.

[0060] Specifically, the input of the isolated DC power supply 2 can be 380V three-phase alternating current or 690V three-phase alternating current, and the voltage of the input power supply can be selected according to specific conditions such as the size of the wind turbine blade and the climate conditions of the wind turbine installation environment. As Figure 1As shown in the figure, in this embodiment, the input end of the isolated DC power supply 2 inputs 380V three-phase alternating current. For some large wind turbines (such as MW-class wind turbines) or wind turbines installed in cold climates, in order to provide greater heating power to the wind turbine blades through the low-resistance metal heating component 1, so as to achieve a better de-icing effect, 690V three-phase alternating current can be used as the power input to the input end of the isolated DC power supply 2.

[0061] In the above embodiment, each low-resistance metal mesh and the output grounding end of the isolated DC power supply 2 are effectively connected to the ground by connecting with the wind turbine blade downlead. The low-resistance metal mesh is equivalent to the wind turbine blade downlead and has extremely high lightning strike current impact resistance. Coupled with the fact that the isolated DC power supply 2 can effectively isolate its input and output, when a lightning strike occurs, the lightning can be effectively discharged to the ground through the wind turbine blade downlead, thus achieving good lightning safety protection and effectively avoiding the impact of lightning overvoltage on the electrical control system of the wind turbine blade de-icing system. There is no need to additionally increase the lightning protection shielding layer, thereby minimizing the impact on the mechanical strength and aerodynamic performance of the blade; since the low-resistance metal mesh of the low-resistance metal heating component 1 is laid on the outer surface of the wind turbine blade, the low-resistance metal heating component 1 can be pasted and constructed by using a high thermal conductivity composite adhesive in a hand-laying bonding method, and the installation process is simple; the low-resistance metal mesh heating layer 11 made of low-resistance metal material is used to heat and de-ice the wind turbine blade, effectively improving the overall thermal efficiency and ice melting performance of the wind turbine blade heating and de-icing, and better meeting the de-icing and anti-icing capabilities of the wind turbine under low temperature weather conditions.

[0062] In summary, the above embodiment can simplify the installation process of the electric heating de-icing system while ensuring the de-icing effect and lightning protection ability, and minimize the impact on the mechanical strength and aerodynamic performance of the blade.

[0063] The leading edge of the wind turbine blade is the windward side of the wind turbine blade. When the air temperature and humidity reach the icing condition, the wind will drive the supercooled water in the air to move, causing these supercooled water to hit the wind turbine blade. When there are enough water droplets on the blade, the icing phenomenon occurs. Therefore, the icing of the wind turbine blade mainly concentrates on the windward side, and the leeward side is much weaker. In order to minimize the impact of the wind turbine blade heating system on the mechanical strength and aerodynamic performance of the blade, it is necessary to limit the laying area of the low-resistance metal heating component 1. Therefore, when the laying area is certain, in order to provide the heating efficiency and ice melting performance of the wind turbine blade, as Figure 5As shown, in one embodiment, the low-resistance metal heating component 1 is disposed on the outer surface of the leading edge of the wind turbine blade (i.e., the windward surface). In order to reduce the thermal resistance between the wind turbine blade and the low-resistance metal heating component 1 laid on its outer surface, so that the heat of the low-resistance metal heating component 1 can be transmitted to the surface of the wind turbine blade more quickly, specifically, the low-resistance metal heating component 1 can be adhesively fixed to the leading edge of the fan blade through a high thermal conductivity composite adhesive, which can reduce the temperature rise of the low-resistance metal heating component 1, achieve cold heating and de-icing, effectively reduce heat loss, is beneficial to improving the heating and de-icing efficiency, and prolong the life of the wind turbine blade. Specifically, the high thermal conductivity composite adhesive can adopt alumina-epoxy resin composite adhesive.

[0064] As Figure 1 shown, on the basis of the above embodiment, in order to facilitate the connection between each low-resistance metal mesh and the output terminal of the isolated DC power supply 2 and between two adjacent low-resistance metal meshes, in one embodiment, the low-resistance metal mesh heating layer 11 further includes a positive connection terminal 115, a grounding terminal connection terminal 116, a negative connection terminal 117, a positive short-circuit terminal 118, and a negative short-circuit terminal 119. The output positive pole of the isolated DC power supply 2 is connected to the first low-resistance metal mesh 111 through the positive connection terminal 115. The first low-resistance metal mesh 111 and the second low-resistance metal mesh 112 are connected through the positive short-circuit terminal 118. The second low-resistance metal mesh 112, the third low-resistance metal mesh 113, and the output grounding terminal of the isolated DC power supply 2 are connected through the grounding terminal connection terminal 116. The third low-resistance metal mesh 113 and the fourth low-resistance metal mesh 114 are connected through the negative short-circuit terminal 119. The fourth low-resistance metal mesh 114 and the output negative pole of the isolated DC power supply 2 are connected through the negative connection terminal 117.

[0065] In order to ensure the current-carrying capacity of each connection terminal / short-circuit terminal, thereby improving the overall heating performance and lightning protection impact resistance of the low-resistance metal mesh heating layer 11, the positive connection terminal 115, the grounding terminal connection terminal 116, the negative connection terminal 117, the positive short-circuit terminal 118, and the negative short-circuit terminal 119 are all made of low-resistance metal materials.

[0066] Specifically, in order to ensure the current-carrying and lightning protection effect of the low-resistance metal mesh heating layer 11, the current-carrying cross-section of each low-resistance metal mesh and each connection terminal / short-circuit terminal is not less than the current-carrying cross-section of the downlead of the fan blade.

[0067] Specifically, as Figure 1 、 2, as shown in Figure 6, on the basis of the above embodiments, in one embodiment of the present invention, the ice removal system for wind turbine blades further includes a lightning arrester 3. Specifically, there are two lightning arresters 3, which are respectively arranged on both sides of the blade tip. One lightning arrester 3 is short-circuited to the positive short-circuit row 118 of the low-resistance metal mesh heating layer 11, and the other lightning arrester 3 is short-circuited to the negative short-circuit row 119 of the low-resistance metal mesh heating layer 11. By arranging the lightning arrester 3 and connecting it to the low-resistance metal mesh heating layer 11, lightning can be intercepted by the lightning arrester 3, effectively preventing lightning from directly acting on the low-resistance metal mesh and damaging the low-resistance metal mesh.

[0068] As Figure 3 shown, in one embodiment, the low-resistance metal heating assembly 1 further includes a grid-shaped top fiberglass cloth 12 and a grid-shaped bottom fiberglass cloth 13. The low-resistance metal mesh heating layer 11 is sandwiched between the grid-shaped top fiberglass cloth 12 and the grid-shaped bottom fiberglass cloth 13, and both the grid-shaped top fiberglass cloth 12 and the grid-shaped bottom fiberglass cloth 13 are connected by high thermal conductivity composite adhesive bonding. Since fiberglass cloth is more easily integrated with the blade made of fiberglass material, the arrangement of the grid-shaped top fiberglass cloth 12 and the grid-shaped bottom fiberglass cloth 13 not only facilitates the fixation of the low-resistance metal mesh heating layer 11, but also enables the entire low-resistance metal heating assembly 1 to be better bonded to the blade; the grid-shaped top fiberglass cloth 12, the low-resistance metal mesh heating layer 11, and the grid-shaped bottom fiberglass cloth 13 are connected by high thermal conductivity composite adhesive bonding, effectively reducing the thermal resistance between the low-resistance metal mesh heating layer 11 and the blade, thereby better ensuring the heating and ice melting effect. Specifically, the high thermal conductivity composite adhesive is specifically alumina-epoxy resin composite adhesive.

[0069] Specifically, when installing the low-resistance metal heating assembly 1, first bond the grid-shaped top fiberglass cloth 12, the low-resistance metal mesh heating layer 11, and the grid-shaped bottom fiberglass cloth 13 together in sequence through the high thermal conductivity composite adhesive. Then, after grinding the heating area (such as the leading edge of the blade) of the wind turbine blade, use the high thermal conductivity composite adhesive to bond the low-resistance metal heating assembly 1 to the ground area of the wind turbine blade after grinding by hand lay-up bonding to complete the installation of the low-resistance metal heating assembly 1. The installation process is simple and the operation is convenient.

[0070] In one embodiment, as Figure 6 shown, there is one low-resistance metal heating assembly 1. The first low-resistance metal mesh 111, the second low-resistance metal mesh 112, the third low-resistance metal mesh 113, and the fourth low-resistance metal mesh 114 of the low-resistance metal heating assembly 1 are evenly spaced along the thickness direction of the wind turbine blade, and each low-resistance metal mesh extends along the length direction of the wind turbine blade.

[0071] In some other embodiments, a plurality of low-resistance metal heating components 1 are provided. The plurality of low-resistance metal heating components 1 are arranged at intervals along the length direction of the wind turbine blade. The first low-resistance metal mesh 111, the second low-resistance metal mesh 112, the third low-resistance metal mesh 113, and the fourth low-resistance metal mesh 114 of each low-resistance metal heating component 1 are arranged at uniform intervals along the thickness direction of the wind turbine blade. By providing a plurality of low-resistance metal heating components 1, on the one hand, when the area where the low-resistance metal heating components 1 need to be laid on the wind turbine blade is fixed, the area and weight of each low-resistance metal heating component 1 can be reduced, which is convenient for better bonding the low-resistance metal heating components 1 to the wind turbine blade and further reducing the installation difficulty of the low-resistance metal heating components 1. On the other hand, since the icing degrees in different areas of the wind turbine blade are different, the switches and heating powers of each low-resistance metal heating component 1 can be controlled separately, so that different heating control strategies can be adopted for different areas covered by each low-resistance metal heating component 1, further improving the heating and de-icing efficiency. Specifically, each low-resistance metal heating component 1 can be respectively connected to an isolated DC power supply 2, and the heating power of the corresponding low-resistance metal heating component 1 can be controlled by controlling the output power of the corresponding isolated DC power supply 2; alternatively, the power input ends of the respective low-resistance metal heating components 1 can be connected to the same isolated DC power supply 2, and the heating power of the corresponding low-resistance metal heating component 1 can be adjusted respectively by providing switching tubes or power tubes between the isolated DC power supply 2 and the respective low-resistance metal heating components 1.

[0072] As Figure 4 shown, in one embodiment, each low-resistance metal mesh is a mesh structure formed by intersecting a plurality of transverse low-resistance metal wires 1111 made of a low-resistance metal material and a plurality of longitudinal low-resistance metal wires 1112 made of a low-resistance metal material. The intersections of the transverse low-resistance metal wires 1111 and the longitudinal low-resistance metal wires 1112 are connected by a die-casting connection process. In this embodiment, the main current path is the transverse low-resistance metal wires 1111, and the longitudinal low-resistance metal wires 1112 are heat-conducting wires. The longitudinal low-resistance metal wires 1112 also have a current-sharing effect to ensure the balance of current and heat generation of each metal wire. The intersections of the transverse low-resistance metal wires 1111 and the longitudinal low-resistance metal wires 1112 are connected by a die-casting connection process to reduce the contact resistance.

[0073] As Figure 5 shown, in another embodiment, in order to further increase the lightning current-carrying capacity of the low-resistance metal mesh, each low-resistance metal mesh is a mesh-shaped low-resistance metal foil uniformly provided with a plurality of through holes 1113, and the mesh-shaped low-resistance metal foil is made of a low-resistance metal foil by a die-casting punching process.

[0074] As Figure 1-3As shown, in one embodiment, the de-icing system for a wind turbine blade further includes a temperature-measuring optical fiber 14 disposed in the low-resistance metal heating component 1. The temperature-measuring optical fiber 14 is used to collect the real-time temperature value of the low-resistance metal mesh heating layer 11, so as to monitor the real-time temperature of the low-resistance metal mesh heating layer 11, and adjust the heating power of the low-resistance metal heating component 1 according to the real-time temperature value.

[0075] As Figure 2 shown, in one embodiment, a first control switch 15 is disposed between the output positive pole of the isolated DC power supply 2 and the connection point of the second low-resistance metal mesh 112 and the third low-resistance metal mesh 113, and a second control switch 16 is disposed between the output negative pole of the isolated DC power supply 2 and the connection point of the second low-resistance metal mesh 112 and the third low-resistance metal mesh 113. By setting the first control switch 15 and the second control switch 16, it is convenient to control the on-off between the output positive pole of the isolated DC power supply 2 and the connection point of the second low-resistance metal mesh 112 and the third low-resistance metal mesh 113 as needed, and control the on-off between the output negative pole of the isolated DC power supply 2 and the connection point of the second low-resistance metal mesh 112 and the third low-resistance metal mesh 113. Specifically, in this embodiment, both the first control switch 15 and the second control switch 16 are normally closed contactors. In this way, in the non-heating state, the positive and negative poles of the low-resistance metal mesh heating layer 11 are connected to the output grounding end of the isolated DC power supply 2 through the normally closed contactors. Since the output grounding end of the isolated DC power supply 2 is connected to the down-lead of the wind turbine blade, the de-icing system for the wind turbine blade has the ability to conduct direct lightning current, further improving the lightning protection ability of the de-icing system for the wind turbine blade.

[0076] As Figure 2As shown in the figure, the ice removal system for wind turbine blades further includes a main power switch 17, an input voltage sensor 18, an input current sensor 19, an output voltage sensor 20, an output current sensor 21, an optical fiber temperature measurement module 22, a controller 24, and a communication circuit 23. The main power switch 17, the input voltage sensor 18, the input current sensor 19, the output voltage sensor 20, the output current sensor 21, the optical fiber temperature measurement module 22, and the communication circuit 23 are respectively communicatively connected to the controller 24. The main power switch 17 is used to control the switch of the input power supply of the ice removal system for wind turbine blades. The input voltage sensor 18 and the input current sensor 19 are respectively used to detect the input voltage and input current of the isolated DC power supply 2. The output voltage sensor 20 and the output current sensor 21 are respectively used to detect the output voltage and output current of the isolated DC power supply 2. The optical fiber temperature measurement module 22 is used to collect the real-time temperature information detected by the temperature measurement optical fiber 14. The controller 24 can be communicatively connected to an external control terminal through the communication circuit 23 to control the relevant unit modules (the first control switch 15, the second control switch 16, the main power switch 17, the low-resistance metal mesh heating layer 11, etc.) of the ice removal system for wind turbine blades in response to the control instructions sent by the external control terminal, and send the received information such as the input voltage, input current, output voltage, output current, and real-time temperature to the external control terminal to realize the information interaction between the external control terminal and the ice removal system for wind turbine blades.

[0077] Specifically, as Figure 6 shown in the figure, a power control box 25 is installed at the blade root. The isolated DC power supply 2, the main power switch 17, the first control switch 15, the second control switch 16, the input voltage sensor 18, the input current sensor 19, the output voltage sensor 20, the output current sensor 21, the optical fiber temperature measurement module 22, the controller 24, and the communication circuit 23 are all arranged inside the power control box 25.

[0078] The embodiment of the present application also provides a blade. Please refer to Figure 1-6 the figure, and the above-mentioned ice removal system for wind turbine blades based on low-resistance metal materials is provided on the blade.

[0079] The embodiment of the present application also provides a wind power generating set, and the wind power generating set includes the above-mentioned blade.

[0080] As Figure 8 shown in the figure, the embodiment of the present application also provides an ice removal control method for blades, which is applied to the above-mentioned ice removal system for wind turbine blades based on low-resistance metal materials. The ice removal control method for blades includes the following steps:

[0081] S1, obtaining the real-time temperature value of the low-resistance metal mesh;

[0082] When it is necessary to control the de-icing system of the wind turbine blade to de-ice the wind turbine blade, it is first necessary to obtain the real-time temperature values of each low-resistance metal mesh in the de-icing system of the wind turbine blade.

[0083] Specifically, the real-time temperature value of the low-resistance metal mesh can be obtained by arranging temperature-measuring optical fibers on the low-resistance metal mesh. However, since the entire temperature-measuring optical fiber temperature-measuring system is expensive, it increases the de-icing cost of the wind turbine blade. As Figure 7 shown, since there is a certain relationship between the resistivity of low-resistance metal materials such as copper and aluminum and the temperature, therefore, the method of calculating the resistivity can also be used to obtain the real-time temperature value of the low-resistance metal mesh by looking up a table. The specific steps are as follows:

[0084] S11, sample the output voltage and output current of the isolated DC power supply;

[0085] S12, calculate the resistivity of the low-resistance metal mesh according to the output voltage and output current; Calculating the resistivity according to voltage and current is an existing technology and will not be elaborated here.

[0086] S13, obtain the real-time temperature value of the low-resistance metal mesh by looking up a table according to the temperature-resistivity curve of the low-resistance metal corresponding to the low-resistance metal mesh.

[0087] Using the method of calculating the resistivity to obtain the real-time temperature value of the low-resistance metal mesh by looking up a table can effectively reduce the cost on the premise of ensuring the accuracy and reliability of the real-time temperature value compared with the method of directly detecting through temperature-measuring optical fibers.

[0088] S2, compare the real-time temperature value with a preset temperature reference value, and adjust the heating power of the low-resistance metal mesh according to the comparison result;

[0089] This step specifically includes: comparing the real-time temperature value with a preset temperature reference value, and judging whether the real-time temperature value is greater than the temperature reference value. If so, increase the heating power of the low-resistance metal mesh; if not, decrease the heating power of the low-resistance metal mesh.

[0090] S3, calculate the integral filtering value of the heating power of the low-resistance metal mesh according to the output voltage and output current of the isolated DC power supply;

[0091] This step specifically includes: calculating the heating power of the low-resistance metal mesh according to the output voltage and output current of the isolated DC power supply, and performing integral filtering processing on the heating power of the low-resistance metal mesh to obtain the power integral filtering value.

[0092] S4, detect the ambient temperature value around the wind turbine blade;

[0093] Specifically, the ambient temperature around the wind turbine blade can be detected by a temperature sensor arranged in the wind turbine nacelle.

[0094] S5. Calculate the thermal resistance value between the low-resistance metal mesh and the air based on the heating power integral filter value, the ambient temperature value, and the temperature reference value.

[0095] The specific calculation formula is as follows:

[0096] The thermal resistance value between the low-resistance metal mesh and the air = (temperature reference value - ambient temperature value) / power integral filter value.

[0097] S6. Compare the thermal resistance value with a preset thermal resistance set value, and adjust the temperature reference value according to the comparison result.

[0098] This step specifically includes: comparing the thermal resistance value with the preset thermal resistance set value, and judging whether the thermal resistance value is greater than the thermal resistance set value. If so, it indicates that the ice thickness on the blade is relatively large, and the temperature reference value is set to a larger first reference value; if not, it indicates that the blade is not iced or the ice thickness is relatively small, and the temperature reference value is set to a second reference value; where the first reference value is greater than the second reference value. Specifically, in this embodiment, the first reference value is 50 °C, and the second reference value is 10 °C.

[0099] Since there is a large difference in the thermal conductivity coefficients of ice and water, the thermal conductivity coefficient of ice is 2.22, and the thermal conductivity coefficient of water is only 0.54. Therefore, in order to achieve a better de-icing effect, through the temperature rise control strategy of the low-resistance metal mesh in the blade de-icing control method of the above embodiment of the present invention, it is ensured that under the condition of ice on the blade surface, rapid heat transfer is carried out through the low-resistance metal mesh, so that the ice layer in contact with the blade surface quickly melts and falls off, which can ensure more efficient de-icing of the blade.

[0100] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A de-icing system for wind turbine blades based on low-resistance metal materials, characterized in that, Comprising: A low-resistance metal heating component, which is laid on the outer surface of the wind turbine blade. The low-resistance metal heating component includes a low-resistance metal mesh heating layer, and the low-resistance metal mesh heating layer includes a first low-resistance metal mesh, a second low-resistance metal mesh, a third low-resistance metal mesh, and a fourth low-resistance metal mesh that are arranged at intervals; and An isolated DC power supply, which is used to provide direct current for the low-resistance metal heating component; Wherein, The output positive pole of the isolated DC power supply, the first low-resistance metal mesh, the second low-resistance metal mesh, the third low-resistance metal mesh, the fourth low-resistance metal mesh, and the output negative pole of the isolated DC power supply are connected in sequence to form a closed-loop current circuit. The output grounding terminal of the isolated DC power supply is connected to the connection between the second low-resistance metal mesh and the third low-resistance metal mesh, and then connected to the lead-off wire of the wind turbine blade.

2. The de-icing system for a wind turbine blade based on a low-resistance metal material as described in claim 1, wherein A first control switch is arranged between the output positive pole of the isolated DC power supply and the connection between the second low-resistance metal mesh and the third low-resistance metal mesh, and a second control switch is arranged between the output negative pole of the isolated DC power supply and the connection between the second low-resistance metal mesh and the third low-resistance metal mesh.

3. The de-icing system for wind turbine blades based on low-resistance metal materials according to claim 1 or 2, characterized in that, The low-resistance metal mesh heating layer further includes a positive terminal busbar, a grounding terminal busbar, a negative terminal busbar, a positive shorting bar, and a negative shorting bar. The positive terminal busbar, the grounding terminal busbar, the negative terminal busbar, the positive shorting bar, and the negative shorting bar are all made of low-resistance metal materials; The output positive pole of the isolated DC power supply is connected to the first low-resistance metal mesh through the positive terminal busbar. The first low-resistance metal mesh and the second low-resistance metal mesh are connected through the positive shorting bar. The second low-resistance metal mesh, the third low-resistance metal mesh, and the output grounding terminal of the isolated DC power supply are connected through the grounding terminal busbar. The third low-resistance metal mesh and the fourth low-resistance metal mesh are connected through the negative shorting bar. The fourth low-resistance metal mesh and the output negative pole of the isolated DC power supply are connected through the negative terminal busbar.

4. The de-icing system for a wind turbine blade based on a low-resistance metal material according to claim 3, characterized in that, The low-resistance metal heating component further includes a grid-shaped top fiberglass cloth and a grid-shaped bottom fiberglass cloth. The low-resistance metal mesh heating layer is sandwiched between the grid-shaped top fiberglass cloth and the grid-shaped bottom fiberglass cloth, and both the grid-shaped top fiberglass cloth and the grid-shaped bottom fiberglass cloth are adhesively connected through a high thermal conductivity composite adhesive.

5. The de-icing system for a wind turbine blade based on a low-resistance metal material according to claim 1, 2 or 4, characterized in that, The low-resistance metal heating component is adhesively bonded to the leading edge of the wind turbine blade through a high thermal conductivity composite adhesive.

6. The de-icing system for a wind turbine blade based on low-resistance metal materials according to claim 5, characterized in that One low-resistance metal heating component is provided. The first low-resistance metal mesh, the second low-resistance metal mesh, the third low-resistance metal mesh, and the fourth low-resistance metal mesh are evenly spaced along the thickness direction of the wind turbine blade, and each low-resistance metal mesh extends along the length direction of the wind turbine blade; or Multiple low-resistance metal heating components are provided. The multiple low-resistance metal heating components are spaced along the length direction of the wind turbine blade. The first low-resistance metal mesh, the second low-resistance metal mesh, the third low-resistance metal mesh, and the fourth low-resistance metal mesh of each low-resistance metal heating component are evenly spaced along the thickness direction of the wind turbine blade.

7. The de-icing system for wind turbine blades based on low-resistance metal materials according to claim 1, 2, 4 or 6, characterized in that each low-resistance metal mesh is a mesh structure formed by the intersection of a number of transverse low-resistance metal wires made of low-resistance metal materials and a number of longitudinal low-resistance metal wires made of low-resistance metal materials, and the intersections of the transverse low-resistance metal wires and the longitudinal low-resistance metal wires are connected by a die-casting connection process; or each low-resistance metal mesh is a mesh-shaped low-resistance metal foil evenly distributed with a number of through holes, and the mesh-shaped low-resistance metal foil is made of low-resistance metal foil sheets by a die-casting punching process.

8. A blade de-icing control method, applied to the wind turbine blade de-icing system based on low-resistance metal materials according to any one of claims 1-7, characterized in that, The blade de-icing control method includes: obtaining the real-time temperature value of the low-resistance metal mesh; comparing the real-time temperature value with a preset temperature reference value, and adjusting the heating power of the low-resistance metal mesh according to the comparison result; calculating the heating power integral filtering value of the low-resistance metal mesh according to the output voltage and output current of the isolated DC power supply; detecting the ambient temperature value around the wind turbine blade; calculating the thermal resistance value between the low-resistance metal mesh and the air according to the heating power integral filtering value, the ambient temperature value and the temperature reference value; comparing the thermal resistance value with a preset thermal resistance setting value, and adjusting the temperature reference value according to the comparison result.

9. A blade, characterized in that, The blade is provided with the de-icing system for wind turbine blades based on low-resistance metal materials according to any one of claims 1-7.

10. A wind power generating set, characterized in that, The wind power generating set includes the blade according to claim 9.

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